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Title: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 17, 2018, 01:32:46 am
My band has the Bose F1 top sub system and last week in a larger than typical room we seem to be stressing the subs. The grills were rattling and to the ear the woofers sounded stressed, but also there was not a whole lot of impact on the dance floor.

At the same time, there was no indication of limiting or clipping from the speaker. My thought (and hope) would be that the built in limiter should kick in before there was the potential for damage to the speaker. I guess it's possible that the limit and clip LEDs are not functioning correctly, but it'd be unlikely to have that issue with both subs, right?

Some info on the system and set-up:

Subs are run off an auxiliary send, mains direct from L/R of mixer (Behringer XR18).

Channels sent to Sub Aux - Kick, Bass guitar, tracks, toms, playback audio for set breaks.

Kick and bass have channel HPFs of 45hz and 35hz, respectively.

No channels were clipping and the mixer was in the green.

Something to note: we're all on in ears and it's a silent stage - no amps, no monitors and electronic drums.

System crossover function takes place in the processing of the speaker itself, the Bose manual says it's a 100hz HPF in the tops. I don't know where or if there is a LPF in the subs (or high pass filter, for that matter). We're not using the thru output since the tops are fed directly from the mixer.

We are doing some broad out of band EQ cuts. Sub Aux has a -15db "Hi cut" set at around 200hz. Main outputs to tops have a "Low cut" ~100hz. The output EQs on this mixer do not have actual HPF and LPF available, to my knowledge.

Speaker stacks were placed the 2ft tall stage. If my math is right boundary cancellation should've been just out of the subwoofer passband, ~100-130hz. Rear wall was 25', and side walls were greater than 30' from each stack.

-----------------------

Any thoughts from Bose F1 users, or input from anyone else?
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Chris Grimshaw on December 17, 2018, 03:23:48 am
Some thoughts:

Since the mains and subs have their own processing built-in to perform crossover duties, you shouldn't need to mess around with EQ/crossovers at the desk. -15dB at 100Hz on the main speakers will be losing you energy in the 100-150Hz range (where a lot of "punch" lives, and also messing things up around the 100Hz crossover point. You can bet the 200Hz cut on the subs isn't helping, either.

Chances are you've then increased the level on the subs to compensate for the lack of "punch", which has mostly boosted the lower bass, which is a lot of work for the sub drivers.


Next up, bear in mind the subs are only a pair of 10"s, so you've got less cone area than a 15" per side. 4x10"s in total would probably match a single 18". How big was the room?

I have some main speakers that use a pair of (very good) 10"s per side, and I'd hesitate to run a full band in a large room through them.
I think this is simply a case of not enough rig for the gig (although your EQ cuts won't help). If you're regularly doing rooms that size, I'd consider upgrading your PA system. If it's less frequent, I'd look at renting in racks-n-stacks from an external supplier.

Chris
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: John P. Farrell on December 17, 2018, 10:48:35 am
Some thoughts:

Since the mains and subs have their own processing built-in to perform crossover duties, you shouldn't need to mess around with EQ/crossovers at the desk. -15dB at 100Hz on the main speakers will be losing you energy in the 100-150Hz range (where a lot of "punch" lives, and also messing things up around the 100Hz crossover point. You can bet the 200Hz cut on the subs isn't helping, either.


Chris beat me to it....adding the EQ won't help you get more out of a system of that design, and in fact will severely affect the way the crossover and built in processing work, not to mention time alignment of the system.  Apologies if you've accounted for this and realigned everything.  It's actually a great lab test for Smaart....look at the phase relationship of your main outs compared to the subs in a properly set system (theoretically the factory settings for the F1) and then HPF the mains and see what happens. 

Honestly I would look for a proper rig for a gig that size, silent stage or not.  There are lots of racks & stacks available for short $ if its an occasional hit for you.

JF
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 17, 2018, 11:23:24 am
Thanks for the reply.

To clarify - my role in the band is a hired gun bass player, I'm just helping out with sound trying to improve the product. Ultimate decisions on operation on not up to me, but they will seriously consider my advice.
Some thoughts:

Since the mains and subs have their own processing built-in to perform crossover duties, you shouldn't need to mess around with EQ/crossovers at the desk. -15dB at 100Hz on the main speakers will be losing you energy in the 100-150Hz range (where a lot of "punch" lives, and also messing things up around the 100Hz crossover point. You can bet the 200Hz cut on the subs isn't helping, either.

These out of pass band cuts were implemented before I started with the band. In fact, they were using graphic EQ's on the master and sub aux buses to accomplish this and switched those to 5 band parametrics in the hope of smoothing out the response. 

I will eliminate those cuts completely next time we fire the system up and see what happens.

Chances are you've then increased the level on the subs to compensate for the lack of "punch", which has mostly boosted the lower bass, which is a lot of work for the sub drivers.

Yes, I'm sure. In fact the gain structure is all out of wack because the sub aux level and main level faders get shifted in soundcheck and through the night. We listen and go "hey, where's the punch" and then push the sub faders but still don't get the response we want. The relative acoustical crossover point gets shifted every time that happens, and I don't even know if our starting point is the correct balance.

I would like to get rid of the aux fed subs completely right now and just run it all straight from the mains with the cabinets' internal processing doing all the work. It'll simplify setup and the signal chain. Eliminating the variables of changing top and sub faders level may go a long way.

Next up, bear in mind the subs are only a pair of 10"s, so you've got less cone area than a 15" per side. 4x10"s in total would probably match a single 18". How big was the room?

I have some main speakers that use a pair of (very good) 10"s per side, and I'd hesitate to run a full band in a large room through them.

I think this is simply a case of not enough rig for the gig (although your EQ cuts won't help). If you're regularly doing rooms that size, I'd consider upgrading your PA system. If it's less frequent, I'd look at renting in racks-n-stacks from an external supplier.

We definitely did not have enough rig for the gig. But in any case the clients are not complaining, my inquiry is in the interest of offering a consistent product from event to event.

The room was an old warehouse that's been converted into an event space. The event was a wedding, maybe 250-300 pax? The space to which we were playing was only part of the warehouse, an approximate square maybe 7-8000 sq.ft. The dance floor area was reasonable though, ~30'w x ~45'L.

Hiring in sound is not really an option. I don't deal with the business end at all in this group but I'm sure the margin isn't there to support that. If a higher output system is needed the band would be more inclined to purchase rather than rent, they are willing to invest in what is needed to offer the best service they can long term.

I'm not really concerned about being able to fill a venue that size with concert sound, but want to be able to get good impact on the dance floor, which would typically be no more than 50' deep and usually much less. Events are mostly weddings, corporate parties, etc. Not dance club or rock show volume.

Transport space in the bus's storage bays is limited and we are almost topped out, not to mention the bay door entrances are only 18" tall so typical 18" subs are a non-starter. I have a JBL PRX712/718xlf system that would could utiliize, but transport logistics are an issue. If higher output system was needed consistently a revamping of the entire FOH would probably be needed.

I'd like to figure out what's up with these particular subs. They were not pushing enough air on this show for sure, but while they seem to be struggling the internal processing/protection is giving no indication of any issues. I don't want to end up in a position were we launch those 10" woofers through the grill and not have ever gotten a limit or clip indication.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 17, 2018, 01:02:52 pm
The system is most definitely not time-alinged or Smaarted or anything. Check my reply to Chris, I elaborate on the particulars a bit.

Quote
Chris beat me to it....adding the EQ won't help you get more out of a system of that design, and in fact will severely affect the way the crossover and built in processing work, not to mention time alignment of the system.  Apologies if you've accounted for this and realigned everything.  It's actually a great lab test for Smaart....look at the phase relationship of your main outs compared to the subs in a properly set system (theoretically the factory settings for the F1) and then HPF the mains and see what happens. 

Honestly I would look for a proper rig for a gig that size, silent stage or not.  There are lots of racks & stacks available for short $ if its an occasional hit for you.

JF
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Tim McCulloch on December 17, 2018, 02:20:40 pm
Hi Patrick-

From you description of how the subs physically responded - rattling grilles, etc - give the impression that they were being fed substantial energy near or below the LF tuning.  You might double check that the aux sends were at the correct level and that there was no unusual LF boost applied to one or more of those inputs.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Pat Cognitore on December 18, 2018, 01:11:58 pm
I'll get a look at the mixer settings again this weekend, I'll take a close look then. But we're using in house stacks and racks at the upcoming gig so the mix will be in the hands of the house engineer.

I'm 95% sure there isn't any 'irregular' sub bass being sent to the subs as we are using HPF on all channels. There is no bass eq boosted. It's entirely possible that the HPFs are not high enough.

Bose claims a spec of -3db at 40hz, and -10db at 38hz. The kick channel HP is set at 45hz, and the 5 string bass at 35hz. I can bring the bass up for sure. With the kick I'd want to check the RTA to make sure I'm not gonna start chopping away at the fundamental (it's a roland Vdrum, FWIW).
Hi Patrick-

From you description of how the subs physically responded - rattling grilles, etc - give the impression that they were being fed substantial energy near or below the LF tuning.  You might double check that the aux sends were at the correct level and that there was no unusual LF boost applied to one or more of those inputs.

Sent from my SM-G960U using Tapatalk
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Rob Spence on December 18, 2018, 05:08:47 pm
I'll get a look at the mixer settings again this weekend, I'll take a close look then. But we're using in house stacks and racks at the upcoming gig so the mix will be in the hands of the house engineer.

I'm 95% sure there isn't any 'irregular' sub bass being sent to the subs as we are using HPF on all channels. There is no bass eq boosted. It's entirely possible that the HPFs are not high enough.

Bose claims a spec of -3db at 40hz, and -10db at 38hz. The kick channel HP is set at 45hz, and the 5 string bass at 35hz. I can bring the bass up for sure. With the kick I'd want to check the RTA to make sure I'm not gonna start chopping away at the fundamental (it's a roland Vdrum, FWIW).
Sent from my SM-G960U using Tapatalk

You do realize that even if a filter is set at a value, there is significant energy outside of that setting? It is not a brick wall filter.



Sent from my iPad using Tapatalk Pro
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Pat Cognitore on December 18, 2018, 05:10:45 pm
You do realize that even if a filter is set at a value, there is significant energy outside of that setting? It is not a brick wall filter.



Sent from my iPad using Tapatalk Pro
Yes, I realize that.

Sent from my SM-G960U using Tapatalk

Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Robert Lunceford on December 18, 2018, 06:49:08 pm
Isnít the Bose F1 a turnkey system where you just feed it a full range signal and the the internal crossover and processing does the work?
I would forget about aux fed subs. I doubt that you can improve on what the Bose engineers built into the system, especially with the eq in a xr18.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Luke Geis on December 18, 2018, 07:15:22 pm
Subs on an aux will free up some headroom within the sub, but if you're already running it that way and you are where you are at then there isn't much more to be gained.

A trick I employ to get a little bit more is to use a HP and LP filter set around the operating points. If the subs are only good from frequencies between 40hz and 100hz, then there is no point in letting frequencies beyond those points into the sub. I would use the HP filter set to around 40hz or higher to get rid of subsonic gack the sub won't do anything for. I would set the LP filter to around 100hz or lower in order to free up headroom and rid that part of the system of any signal that it will not be reproducing. This can free up a little bit of headroom and maintain the same impact, but it will only get you a few db or so. The last bit of EQ I would apply is to get rid of the peak frequency ( usually centered around 80hz in subs ) to try and get rid of some distortion and woof from the sub, but this will reduce potential output as you are reducing the peak frequency. It evens out the sound and does allow you to turn up a little more, but the sub won't be any louder than it was before.

Now the brass tacks are about realizing where the stop gap is and what your system is actually capable of. The Bose F1 system isn't exactly a powerhouse and will not rattle your teeth and pant legs. It does good for what it is, but being realistic to its performance capabilities lends it with much to be desired. You simply are out of gas when you can hear audible distortion and parts rattling. There just isn't much more to go beyond that point.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 19, 2018, 12:07:29 pm
Subs on an aux will free up some headroom within the sub, but if you're already running it that way and you are where you are at then there isn't much more to be gained.

A trick I employ to get a little bit more is to use a HP and LP filter set around the operating points. If the subs are only good from frequencies between 40hz and 100hz, then there is no point in letting frequencies beyond those points into the sub. I would use the HP filter set to around 40hz or higher to get rid of subsonic gack the sub won't do anything for. I would set the LP filter to around 100hz or lower in order to free up headroom and rid that part of the system of any signal that it will not be reproducing. This can free up a little bit of headroom and maintain the same impact, but it will only get you a few db or so. The last bit of EQ I would apply is to get rid of the peak frequency ( usually centered around 80hz in subs ) to try and get rid of some distortion and woof from the sub, but this will reduce potential output as you are reducing the peak frequency. It evens out the sound and does allow you to turn up a little more, but the sub won't be any louder than it was before.

Now the brass tacks are about realizing where the stop gap is and what your system is actually capable of...being realistic to its performance capabilities lends it with much to be desired. You simply are out of gas when you can hear audible distortion and parts rattling. There just isn't much more to go beyond that point.

Just want to note that your advice of utilizing out of band filters is opposite of that of several other posters. I'd be inclined to agree with you.

However, it's also possible those filters are robbing some useful energy from the signal and/or causing some phase issues that are affecting the output.

But then again, the problem seems to be too much energy, as evidenced by the strained woofer sounds and grills rattling.

So I find myself agreeing with two completely opposite pieces of advice. Neither of which I don't think is the major issue, because in this instance we really just did not have enough gig for the rig.

And did I mention that while this straining and rumbling is happening that the internal processing seems to be doing jack squat? My hope would be that the limit and/or clip LEDs on the subs would be serving as a dummy indicator (as in: 'turn it down, dummy') but they're not.

The Bose F1 system isn't exactly a powerhouse and will not rattle your teeth and pant legs. It does good for what it is...

It sounds OK with playback. It's got that 'loudness button on', smiley face output that most folks seem to like. But TBH, at the price point of this Bose I would've expected and lot more output and much better quality audio. But I'm sure there were business reasons (that I'm not privy to) that this particular system was purchased.

Isnít the Bose F1 a turnkey system where you just feed it a full range signal and the the internal crossover and processing does the work?
I would forget about aux fed subs. I doubt that you can improve on what the Bose engineers built into the system, especially with the eq in a xr18.

Agreed. The bus outputs do not have steep slope filters available, only a 12db per octave 'low cut'. And my preference in running this system would be straight from L/R with no aux fed subs, but that is not how the system has been run in the years before I joined the group.

We did take 5 minutes before the last gig to rewire the system to run as you spec'd above, without aux subs. It seemed to have a bit more full-range clarity to my ear, but was not a revelation in any way. In fact, I would've needed to redo the mix completely as the balance between channels ended up out of whack. That fact in itself tells me that our gain staging and balance between tops and aux-fed subs is not right.
--------------------

My role in this band is as the bass player. I've been with the band almost three months and they've be gracious enough to allow me to take on some audio duties. I'm now seeing and hearing less than optimal things in the system and want to help improve them. But it also puts me in the delicate situation of seeming to criticize the previous operation choice of my employer, so I want to have a full understanding of what the issue(s) may be and offer a recommended solution framed in the proper way.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Paul G. OBrien on December 19, 2018, 01:06:07 pm
It sounds OK with playback. It's got that 'loudness button on', smiley face output that most folks seem to like. But TBH, at the price point of this Bose I would've expected and lot more output and much better quality audio. But I'm sure there were business reasons (that I'm not privy to) that this particular system was purchased.

Bose has always claimed a level of superiority in their advertising that attracts a certain consumer who simply takes their word for it, they do generate very stylish and compact products that perform well for their size but one thing they have never accomplished is LOUD. And I don't mean loud for the sake of it I mean loud with control, I am yet to hear any Bose product that sounds any good beyond about 3/4 of full output, yet I have standard PA speakers that are regularly pushed to limiting with very little audible degradation. For what you get their products are over priced IMO, it definitely seems that you don't have enough rig for the gig and adding more subs would be a solution but if there is a decision to spend more money you have to ask yourself if a wholesale change to something that really is better would be money better spent.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: lindsay Dean on December 19, 2018, 01:19:34 pm
The Bose system you have is okay for medium low-level use
I E music playback, speech, acoustic acts.
but it will never carry a full band as said before to a decent volume.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 19, 2018, 02:49:20 pm
The Bose system you have is okay for medium low-level use
I E music playback, speech, acoustic acts.
but it will never carry a full band as said before to a decent volume.

I hear you. But even now with the 15% off sale Bose is running this system is over $4000. The standard street price with carry bags had been over $5000.

And there would be no need for $2000+ worth of subs for speech or acoustic use.

Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Jay Marr on December 19, 2018, 03:09:38 pm
I hear you. But even now with the 15% off sale Bose is running this system is over $4000. The standard street price with carry bags had been over $5000.

And there would be no need for $2000+ worth of subs for speech or acoustic use.

I have a friend with this same system and they often have the same issue with the subs not keeping up with the tops.
Standard bar band.

It's simply not enough rig for the gig.

He often swaps out the subs for QSC KW118s or QSC HPR118s and has much more punch and headroom on the low end.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Luke Geis on December 19, 2018, 05:35:03 pm
You should note that I said, " to get a little more ". This implies that phase and system tuning is now irrelevant to the task at hand which is to:

A. Keep the system from blowing up

B. Get a little more potential SPL while adhering to A.

The phase issues are not an issue as much if you do your system tuning with those filters in place ( ala Smaart or other measurement software ). The HP filter will not be so problematic as much as the LP filter will be. With the type of slope utilized in most HP/LP filters, the resultant phase shift will be negligible or at least minimally invasive. Especially in subs on aux systems where only a few key instruments are introduced into both halves of the system.

Now ideally you shouldn't need to do any kind of out of band EQing, but when you think about its concept, it makes total sense. Mostly it depends on your system type and setup. In the case where you are using a crossover that has three inputs ( one for the subs ) the three inputs will see the total of the signal you send it. In the case of the subs, a lot of that info is not going to be amplified and is simply eating headroom into the input. Secondly, the crossover will do what it does, but the information that is out of band still exists and still utilizes headroom. Reducing most of the information just outside of the crossovers bands allows all of the relevant signals through at the cost of some slight phase issues, but free's up that much more headroom and rids that part of the system of that much more information that would cause phase issues anyways.

We all like to think that when we align the subs and the mains that they are both in perfect phase harmony. This could not be further from the truth. It will only ever be correct in one specific superposition and it will only be correct over a small segment of the frequency response. When we align the subs to the mains we align for the best phase at a frequency range of interest ( decided by magnitude response and resultant crossover points ). The rest is still out of phase, we just see it as phase wraps that appear to line up. Perhaps I need to do a video on it? In either case, the phase shift introduced by the HP/LP filters is not really a huge issue in the grand scheme of things. If you need more mileage out of your system, the small sacrifice is probably going to be outweighed by the benefits.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 19, 2018, 07:12:37 pm
You should note that I said, " to get a little more ".
I agree with your approach and the reasoning.

It's likely that in these instances we need more than a little more. I'm not sure what that is  - 3db, 6db, 15db? My guess is at least 6db, which we would get from doubling the subs. Not sure that makes sense. Well, I am sure...it doesn't. But I don't make the financial decisions.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Luke Geis on December 19, 2018, 08:25:10 pm
My experience shows that with subs on an aux you can acquire roughly 9db of headroom in conjunction with out of band EQ. The vocals really eat up a lot of media in the low end despite the HP filter.

This does not negate not having enough rig for the gig of course. While I think 6db is probably the minimum needed to get from not enough to just enough, another 3db isn't going to take you from just enough to more than enough. For me, it is more about getting a safety margin back from a known point of performance. I have the level I need, but the limit light is flickering on, how can I eliminate that? I have not specifically tested this technique in the real world to see just how much it truly saves, but in one experiment I did with Reaper I showed a 4db improvement with just the out of band EQ alone. With the EQ and simulated subs on aux I saw a 7db improvement overall.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Tim McCulloch on December 19, 2018, 08:37:53 pm
My experience shows that with subs on an aux you can acquire roughly 9db of headroom in conjunction with out of band EQ. The vocals really eat up a lot of media in the low end despite the HP filter.

This does not negate not having enough rig for the gig of course. While I think 6db is probably the minimum needed to get from not enough to just enough, another 3db isn't going to take you from just enough to more than enough. For me, it is more about getting a safety margin back from a known point of performance. I have the level I need, but the limit light is flickering on, how can I eliminate that? I have not specifically tested this technique in the real world to see just how much it truly saves, but in one experiment I did with Reaper I showed a 4db improvement with just the out of band EQ alone. With the EQ and simulated subs on aux I saw a 7db improvement overall.

I'm skeptical.  Out of band EQ is good for a couple of things but making a +7dB batch of Magically Delicious Headroom ain't one of them.  My measured experience was about +3dB, you pick where the compromise occurs.

The more I think about Patrick's situation the more it seems likely that they ventured into the Land of Unrealistic Expectations (due south of the Land of Misfit Toys).
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Caleb Dueck on December 19, 2018, 11:13:27 pm
I'm skeptical.  Out of band EQ is good for a couple of things but making a +7dB batch of Magically Delicious Headroom ain't one of them.  My measured experience was about +3dB, you pick where the compromise occurs.

The more I think about Patrick's situation the more it seems likely that they ventured into the Land of Unrealistic Expectations (due south of the Land of Misfit Toys).

As soon as I saw the thread title, my first thought was "Not enough rig for the gig". 

I've also used out of band  and creative EQ and HP/LP filters to "help" low grade equipment get through a show without dying.  Agreed that some "creative crap coercion" can give less-bad sound, but it can't give much if any extra headroom.  Mainly raising the HPF on subs by 5Hz or so. 
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Chris Grimshaw on December 20, 2018, 03:45:46 am
With the EQ and simulated subs on aux I saw a 7db improvement overall.

I'm also skeptical.
Did you make sure you'd be within cone excursion limits?
What about port air velocity getting too high?


You should note that I said, " to get a little more ". This implies that phase and system tuning is now irrelevant to the task at hand which is to:

A. Keep the system from blowing up

B. Get a little more potential SPL while adhering to A.

<snip>

Now ideally you shouldn't need to do any kind of out of band EQing, but when you think about its concept, it makes total sense. Mostly it depends on your system type and setup. In the case where you are using a crossover that has three inputs ( one for the subs ) the three inputs will see the total of the signal you send it. In the case of the subs, a lot of that info is not going to be amplified and is simply eating headroom into the input. Secondly, the crossover will do what it does, but the information that is out of band still exists and still utilizes headroom. Reducing most of the information just outside of the crossovers bands allows all of the relevant signals through at the cost of some slight phase issues, but free's up that much more headroom and rids that part of the system of that much more information that would cause phase issues anyways.

We all like to think that when we align the subs and the mains that they are both in perfect phase harmony. This could not be further from the truth. It will only ever be correct in one specific superposition and it will only be correct over a small segment of the frequency response. When we align the subs to the mains we align for the best phase at a frequency range of interest ( decided by magnitude response and resultant crossover points ). The rest is still out of phase, we just see it as phase wraps that appear to line up. Perhaps I need to do a video on it? In either case, the phase shift introduced by the HP/LP filters is not really a huge issue in the grand scheme of things. If you need more mileage out of your system, the small sacrifice is probably going to be outweighed by the benefits.

With regards to the first chunk of text...

- Using headroom on the input of a crossover isn't as evil as you seem to imply.
- The signals you're attenuating with out-of-band EQ are already being attenuated by the crossover. Why not just use a steeper crossover slope and maintain phase alignment?

For the second chunk of text...
- When the main speakers and subwoofers are vertically aligned, the right crossover will mean they're working in "perfect phase harmony" over the entire dancefloor, stage, and load-in area. Both cabinets will be omnidirectional at 100Hz, so we've got rotational symmetry.
- If the phase wraps line up, the speakers are still in phase.
- The phase shifts from crossover filters are an issue. The phase shifts determine if the crossover is gonna work correctly (ie, get the drivers working together) or not (drivers cancelling each other out).


Ignoring the proper summation between cabinets is a sure-fire way of losing some SPL, which directly contradicts what you're trying to achieve.

Chris
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 20, 2018, 12:18:44 pm
I believe it. Although I've found that with many systems more subs are needed. I really prefer 2 subs for every one top with my PRX700 system.

I will say that we've actually had an issue with the tops clipping (on snare hits) if main output get pushed too much. The subs however are not clipping or limiting, but yet the balance is still way off with not enough low end and the aforementioned 'bad sounds' coming from the cabs.

I have a friend with this same system and they often have the same issue with the subs not keeping up with the tops.
Standard bar band.

It's simply not enough rig for the gig.

He often swaps out the subs for QSC KW118s or QSC HPR118s and has much more punch and headroom on the low end.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Luke Geis on December 20, 2018, 08:33:58 pm
Ok, I made a video showing two different scenarios in which both showed at least a +6db increase in headroom in more real-world use. What it is: Shows that roughly +6db ( possibly more depending on how you apply the EQ and all ) is easily attainable if needed without significant detriment to the sound. What it isn't: It is not a cure-all and it does have downsides, those downsides are probably not of worry if you need to employ the trick anyway.

https://www.youtube.com/watch?v=2x6Ag3tefi0
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on December 21, 2018, 11:05:53 am
"There is a phase shift, but you're not gonna die". ;D

Looks good, thanks for doing the video.

Forgive my ignorance, I'm assuming the source material is pink noise? And I'd guess that the reduction that the out of band filters have at the sub input could be even greater (or less) depending on the real world program material.

Ok, I made a video showing two different scenarios in which both showed at least a +6db increase in headroom in more real-world use. What it is: Shows that roughly +6db ( possibly more depending on how you apply the EQ and all ) is easily attainable if needed without significant detriment to the sound. What it isn't: It is not a cure-all and it does have downsides, those downsides are probably not of worry if you need to employ the trick anyway.

https://www.youtube.com/watch?v=2x6Ag3tefi0
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Luke Geis on December 21, 2018, 05:25:50 pm
^^^^^^^ Correct on pink noise. Many may not have noticed, but the subs were on and producing noise the whole time. You couldn't really tell when I switched the EQ in and out.

The crossover in this case was set at 120hz, and the HI-cut filter was set at 140hz. You could reduce even more energy by running the HI-cut filter lower to 120hz or wherever your crossover was set if you wanted. Also the Low-pass filter was set at 30hz in this case, most subs don't reproduce that low ( especially single 18" units ) and you could run it up as far as the -10db rating of the sub ( around 35hz for most ).

The pink noise vs. typical media won't really change the outcome much. Perhaps another db or two, but nothing significant. This trick is truly only worth 6-9db in headroom increase which as mentioned before isn't going to be enough in most cases to get from zero to hero.

Going back to the purpose of this trick, the phase shift is probably the least of one's worries. If they didn't even time align things to begin with, your shooting in the dark anyway. The one reason I don't really worry about major phase issues with subs on an aux is because so little media is in the subs anyway and the problems associated with phase shift are really SPL and co-location dependent. If the subs are somewhat well aligned and the crossover is set for a good acoustic setting ( as in electrically they are not the same ), most of the media that would be problematic with phase will be out of the equation anyway even if you don't take the time to re-align after employing this trick.

Humans cannot detect phase when the two sources are independent of one another. Heck we can barely locate the source of where an 80hz signal is coming from. This is another reason I am a fan of utilizing low crossover settings for subs. I typically run no higher than 80hz if I can and will go as low as 60hz if the mains will allow for it. I also try and set the crossover of the mains to get the most even transition from the subs. This usually means a higher crossover setting between 80hz to 100hz or higher depending on the sub. Keeping in mind that at typical crossover points around 80-100hz, the mains and subs can be out of alignment by as much as 2.5' to as much as 3.5' and still couple well enough. So if you align the subs and mains at all, the introduction of the out of band EQ will still have the subs within 90* of phase. You won't die.......
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: brian maddox on December 21, 2018, 08:34:07 pm
^^^^^^^ Correct on pink noise. Many may not have noticed, but the subs were on and producing noise the whole time. You couldn't really tell when I switched the EQ in and out.

The crossover in this case was set at 120hz, and the HI-cut filter was set at 140hz. You could reduce even more energy by running the HI-cut filter lower to 120hz or wherever your crossover was set if you wanted. Also the Low-pass filter was set at 30hz in this case, most subs don't reproduce that low ( especially single 18" units ) and you could run it up as far as the -10db rating of the sub ( around 35hz for most ).

The pink noise vs. typical media won't really change the outcome much. Perhaps another db or two, but nothing significant. This trick is truly only worth 6-9db in headroom increase which as mentioned before isn't going to be enough in most cases to get from zero to hero.

Going back to the purpose of this trick, the phase shift is probably the least of one's worries. If they didn't even time align things to begin with, your shooting in the dark anyway. The one reason I don't really worry about major phase issues with subs on an aux is because so little media is in the subs anyway and the problems associated with phase shift are really SPL and co-location dependent. If the subs are somewhat well aligned and the crossover is set for a good acoustic setting ( as in electrically they are not the same ), most of the media that would be problematic with phase will be out of the equation anyway even if you don't take the time to re-align after employing this trick.

Humans cannot detect phase when the two sources are independent of one another. Heck we can barely locate the source of where an 80hz signal is coming from. This is another reason I am a fan of utilizing low crossover settings for subs. I typically run no higher than 80hz if I can and will go as low as 60hz if the mains will allow for it. I also try and set the crossover of the mains to get the most even transition from the subs. This usually means a higher crossover setting between 80hz to 100hz or higher depending on the sub. Keeping in mind that at typical crossover points around 80-100hz, the mains and subs can be out of alignment by as much as 2.5' to as much as 3.5' and still couple well enough. So if you align the subs and mains at all, the introduction of the out of band EQ will still have the subs within 90* of phase. You won't die.......

^^^^ My name is Brian Maddox and i approve this message....
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 02, 2019, 01:28:54 pm
Minor Update:

Played the same venue as the OP on Saturday, 12/29.

I should note I didn't mix this time around, but just added some tweaks during soundcheck. Also, I used a different bass on this gig than the last one. And the one I used on this gig has much less fundamental presence on Low B and E strings than my other bass, according to the mixer EQ RTA.

I raised the Bass HPF to 40hz. The aux fed sub routing stayed the same, but I lowered the out of band 'low pass' (really just a 'high cut EQ') to around 120hz.

System volume was kept lower overall and that kept the system from sounding strained. Even at that lower level my bass was causing the tops to go into limit (yes, the tops not the subs). Lowering the compression threshold to -40db on that channel kept them out of limit.

The mix overall ended up sounding OK, but really just not enough oomph for this size room. This pic is of the dance floor, banquet tables are placed just outside the pillars. This pic shows a small fraction of the room, it extends another 30' behind the camera position and another 50 to 70' on each side.


Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Luke Geis on January 02, 2019, 02:41:40 pm
That is a pretty big room.

I have said it before ( not in this thread ), but I feel that a PA capable of 135db peak is loud enough to do just about any gig that you can appropriately throw at it. Obviously, a pair of 12" speakers won't fill a football stadium. When you start running speakers in larger spaces where you NEED significant SPL beyond 50', lower output units just can't hang.

The theory is simple. After you account for crest factor and safety ( keeping the speaker out of limiting ) you are subtracting a minimum of 16db from the peak capability of a speaker. This places a 135db peak ( not a realistic number anyway, but a factor for performance ) speaker around the 119db area for real-world output capability. This is the output at 1 meter or roughly 3', so you then need to account for losses in the air. The inverse square law says for every doubling of distance you will lose -6db. So at 2 meters ( 6' roughly ), you would then have 113db, 4 meters ( 12' ish ) 107db, etc. etc.... 12' away is usually enough for smaller gigs to have the core of the people and needed coverage to be within. This allows you to hit rock show volume over an area roughly 50'-75 wide and about 24' deep ( just over 100db at 24' deep ). 24' is the practical limit in distance away from the PA where you can't concern yourself with " Rock show levels " anymore with typical point source PA's. You can have reasonable output to 50', but it won't be over 100db over a considerable bandwidth.

There is another mathematical calculation which the name and calculation escapes my brain at the moment, but it prescribes a slightly different outcome than the inverse square law. It states that the attenuation over distance is dependent upon the wavelength. This is why low frequencies tend to carry over a further distance. Higher frequencies are quickly eaten up by the atmosphere and dissipated. Not really to the point, but just to explain why it seems that lower frequencies do carry out better.

Getting back on topic, you can see how a PA almost needs to be at least capable of about 133db at a minimum in order to just be able to get realistic SPL's that move air. Once you start getting below about a 133db peak speaker though, the truth in advertising starts to show; or not... We are banking on whether the peak SPL number a speaker says it can do is real. We assume that the number can be touched briefly over a series of frequencies that are said to be within +/- 3db. We know that is BS, but it is an indicator of performance. The reduction I do of 16db accounts for 6db of that output being just for safety. Or simply put, if I powered the speaker only up to its continuous rating. The other 10db is really more a pipe dream and assumes you can get the media to within a -10db crest factor.

Most live bands sit around a -15db crest factor withlight to moderate compression. I can get to a -10db crest factor with a live band, but it starts to sound sort of processed at that point. You can just tell that there is something going on because the dynamics are essentially gone and everything sounds like it's at 11 all the time. Really in your face and locked in kind of sound. I like this because it makes the job of mixing easier ( like being in the box ), but musicians don't tend to like it if they notice it, or even hear that you have compression on their channel. I have only met a handful of musicians in my day who are truly masters at modulating their dynamics, and if they were all that good, we wouldn't need compression at all. The need for getting the crest factor down to -10db isn't even always a matter of needing to glue the mix together, but literally a need to keep from blowing the PA up. You can't have spurious snare hits, bass slaps or horn blasts that sail uncontrolled through the PA when you are near the PA's limits. As you have noted you had to limit the Bass channel a bit to keep the PA out of limiting. You already know at this point that you need more rig for the gig, but as seen there are tricks to get a little more. You went from subs that were obviously distorting to not even going into limiting and found that limiting certain instruments helps keep the PA intact.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Robert Lunceford on January 02, 2019, 11:30:32 pm
Minor Update:

Played the same venue as the OP on Saturday, 12/29.

I should note I didn't mix this time around, but just added some tweaks during soundcheck. Also, I used a different bass on this gig than the last one. And the one I used on this gig has much less fundamental presence on Low B and E strings than my other bass, according to the mixer EQ RTA.

I raised the Bass HPF to 40hz. The aux fed sub routing stayed the same, but I lowered the out of band 'low pass' (really just a 'high cut EQ') to around 120hz.

System volume was kept lower overall and that kept the system from sounding strained. Even at that lower level my bass was causing the tops to go into limit (yes, the tops not the subs). Lowering the compression threshold to -40db on that channel kept them out of limit.

The mix overall ended up sounding OK, but really just not enough oomph for this size room. This pic is of the dance floor, banquet tables are placed just outside the pillars. This pic shows a small fraction of the room, it extends another 30' behind the camera position and another 50 to 70' on each side.

After seeing the photo of the room, I believe it is possible that the problem is not with the Bose system but with the room. I am taking an educated guess that the room is very reverberant and that even with no music, the sound level from the crowd alone is very high. I doubt that using a louder system would sound any better in that room. I think you are fighting a losing battle trying to compete with the crowd noise. I would also guess that even with no crowd, and just the band playing, that the sound is bouncing around so much that it is hard to hear anything clearly. A natural reaction is to turn it up louder since it is hard to hear any detail. This is wrong and you should actually turn down the volume to try and get some clarity by reducing the level of the sound bouncing around.
I looked on youtube for some F1 videos and Bose seems to have sold quite a few of these units and they sound surprisingly good in many of the videos. I was surprised how good they sounded and the level that they were playing in some fairly large rooms and outdoors.
Here is an official Bose video where they placed a F1 system in a 1,000 seat concert venue and had several top level engineers try the system out.   https://www.youtube.com/watch?v=keUtck_F7es

 
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 02, 2019, 11:46:42 pm
After seeing the photo of the room, I believe it is possible that the problem is not with the Bose system but with the room. I am taking an educated guess that the room is very reverberant and that even with no music, the sound level from the crowd alone is very high. I doubt that using a louder system would sound any better in that room. I think you are fighting a losing battle trying to compete with the crowd noise. I would also guess that even with no crowd, and just the band playing, that the sound is bouncing around so much that it is hard to hear anything clearly. A natural reaction is to turn it up louder since it is hard to hear any detail. This is wrong and you should actually turn down the volume to try and get some clarity by reducing the level of the sound bouncing around.

That's true. The room is an old warehouse. Concrete floors/walls, some glass, etc. When you're in it it's a little deceiving how large the space is because with decor they make is seem a bit more intimate. The room doesn't inherently sound band, I've played in much worse rooms. But it's not great either.

This last weekends had fewer people that the one we did earlier in December. That factor, along with the slight EQ and compression fixes, lower overall levels and different bass guitar all combined to make for a better night.

Bottom line, the system works way better when you don't try to make it do what it won't do.

I looked on youtube for some F1 videos and Bose seems to have sold quite a few of these units and they sound surprisingly good in many of the videos. I was surprised how good they sounded and the level that they were playing in some fairly large rooms and outdoors.

Here is an official Bose video where they placed a F1 system in a 1,000 seat concert venue and had several top level engineers try the system out.   https://www.youtube.com/watch?v=keUtck_F7es
Ouch. I hope they all were paid well.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 03, 2019, 12:18:50 am
I agree and understand with all you posted. And I would actually be OK with a more compressed mix. This is a wedding band playing with tracks and doing top 40, we're not making high art here. The more impact we can get the better, nuance and dynamics be damned. ;)

You already know at this point that you need more rig for the gig, but as seen there are tricks to get a little more. You went from subs that were obviously distorting to not even going into limiting and found that limiting certain instruments helps keep the PA intact.
That last bit you mention is key, with one correction. The subs were NOT going into limiting or clipping at any time.  I would be happy if I saw either the limit or clip indicators, but they've never given any visual indication of that and it makes me think the LEDs and/or processing is not working in some way.

That's why in my OP I asked if other users were having this issue or could shed some light on the distorting but not limiting/clipping situation.

Another big factor was the 5 string bass I used on the most recent gig has a totally different fundamental response than my custom 6 string that I used on the previous gig. My 6 string has a surprising amount of fundamental present on the lowest notes, so the 35 to 50hz range lights up the RTA pretty good when I'm playing down that end. And when I slap or double thumb the impact is pretty significant in the frequency range. I recently bought that 5 string as my "road bass" so I don't have to subject my custom axe to these types of gigs, and that may work out to an advantage when reinforcing it through this system.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 03, 2019, 12:29:04 am
Bonehead omission.

The other big change I made for this gig was the PA was placed on the floor, not on the 2' tall stage. And I toed them in so they crossfired a bit into the dance floor. This gave a broadband hotspot about 20-25' out on the dance floor, which was a good thing IMO.

I also think it gave smoother and clearer coverage to the areas outside the main dance floor. Bose claims 100* horizontal dispersion, and there is no way that's accurate for most of the mid/high spectrum. The sound starts to get muffled about 30* off axis. With a cross-fired arrangement the patrons to the sides get the most direct sound from the speaker opposite them. The volume is lower but clearer, and when I walked room a bit I was much more satisfied with the coverage.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Scott Holtzman on January 03, 2019, 02:33:26 am
Bonehead omission.

The other big change I made for this gig was the PA was placed on the floor, not on the 2' tall stage. And I toed them in so they crossfired a bit into the dance floor. This gave a broadband hotspot about 20-25' out on the dance floor, which was a good thing IMO.

I also think it gave smoother and clearer coverage to the areas outside the main dance floor. Bose claims 100* horizontal dispersion, and there is no way that's accurate for most of the mid/high spectrum. The sound starts to get muffled about 30* off axis. With a cross-fired arrangement the patrons to the sides get the most direct sound from the speaker opposite them. The volume is lower but clearer, and when I walked room a bit I was much more satisfied with the coverage.
Important note, compressing a signal increases it's overall power level and heats up the driver faster.



Sent from my VS996 using Tapatalk

Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Chris Grimshaw on January 03, 2019, 04:18:50 am
Important note, compressing a signal increases it's overall power level and heats up the driver faster.


... If you apply make-up gain.
If not, you've made some bits quieter, which would decrease power levels a little.


The video made me chuckle - they must've got paid for that.
Having seen an F1 system used next to mine, I can say that HF horns still rule, and there's still no replacement for displacement when it comes to subwoofers. 4x 10"s is less cone area than 2x 15".
I can see it'd be an improvement over the usual Wharfedale 15"/1" + 18" subs that bar bands often buy, but that's about it.


To Patrick,
I'd make sure the F1 system is working as it's meant to - run the setup as stereo (no Aux-fed subs), connect the mains to the subs in the way recommended by the manual, and start troubleshooting. Play music and crank it - does the system still sound stressed? What if you connect your bass?

From the picture, I suspect it's simply not enough rig for the gig. FWIW, if a client sent me that photo and the room dimensions you've described, I'd be thinking about 4x 15" subs, 2x 2x10" mains, and around 10KW of amplification.

Chris
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Paul G. OBrien on January 03, 2019, 12:07:37 pm
I looked on youtube for some F1 videos and Bose seems to have sold quite a few of these units and they sound surprisingly good in many of the videos.

It doesn't take much SPL to distort the mic input on a cell phone so any such video posted online with clear sound means it wasn't terribly loud at the camera position.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Robert Lunceford on January 04, 2019, 01:41:47 am
It doesn't take much SPL to distort the mic input on a cell phone so any such video posted online with clear sound means it wasn't terribly loud at the camera position.

There was no distortion. The sound was clear and sounded full range.
Here is one example.
https://www.youtube.com/watch?v=AzWCqo5iFMA
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 04, 2019, 02:32:27 am
There was no distortion. The sound was clear and sounded full range.
Here is one example.
https://www.youtube.com/watch?v=AzWCqo5iFMA
Robert - have you used this system with a live band in different environments? If so I'd like to hear your opinion on it.

But a judgement made from watching youtube videos posted by other people in circumstances much different than mine doesn't provide much valuable input.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Tim McCulloch on January 04, 2019, 11:10:00 am
We did a gig with an act that is using F1 for "stage fills" in larger rooms with provided PA, and as the PA in clubs.  I generally support performers being self-contained on stage so as to give them repeatable experiences and increase their comfort level.

Lots of "level control" actions - electronic drum kit (sounded better than many), direct outputs from modeling guitar amps run at (initially) reasonable levels.  The only thing making lots of noise was the star's GTR rig and it got louder all night.

In the 2000 capacity venue this show was played it's hard to say how the F1s sounded on stage (they got louder than I expected, SQ was another matter) because I mixed the whole show up the the GTR level.

The guy who wanted more control over the stage sound effectively sabotaged his own efforts.  At the end of the night I said "good luck with the F1s, I hope you find the stage presence you're looking for.  I wanted to say "go IEM and put your amp in an iso box"...
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Greg_Cameron on January 10, 2019, 02:24:43 pm
Having seen an F1 system used next to mine, I can say that HF horns still rule, and there's still no replacement for displacement when it comes to subwoofers. 4x 10"s is less cone area than 2x 15".


^^This^^


There are a lot of posts in this thread, but I think this is what it boils down to: you're not going to get a lot of punch out of a pair of dual 10" reflex or bandpass subs, I don't care who makes them or how much they cost. For the $2400 street price for a pair of these, one could do a lot better spending that money on something else. A pair of JBL SRX818SP b-stock for about the same price would be a substantial upgrade.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 10, 2019, 03:01:47 pm
There are a lot of posts in this thread, but I think this is what it boils down to: you're not going to get a lot of punch out of a pair of dual 10" reflex or bandpass subs, I don't care who makes them or how much they cost. For the $2400 street price for a pair of these, one could do a lot better spending that money on something else. A pair of JBL SRX818SP b-stock for about the same price would be a substantial upgrade.

I agree completely. To reiterate what I stated early on in the thread, I'm just a hired gun in this band, I've only been with the group for 4 months and I don't make any operating or purchasing decisions. They've welcomed my input and opinion, which I appreciate, many bands would've said "we've got this handled, shut up and play your bass." I make the same amount of money per gig whether I have a hand in shaping the sound or not, but if I'm on the gig I want it to sound the best it can.

I've got a pair of PRX718xlf subs sitting unused in my garage. They (and every other 18" sub and many 15" based subs) do not fit in the cargo bay doors of the band's bus, which are 18" tall. The band was using a JBL EON 600 series system and purchased the Bose system last year in part because it was one of the few integrated, self-powered systems that had subs that fit in the storage space. If I was on board then I would've advised them to look at other brands, but to get to the next level of subwoofer performance in a small package requires a jump in price bracket (see: QSC KS212C, JTR C212pro, etc.).
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Tim McCulloch on January 10, 2019, 03:43:16 pm
...but to get to the next level of subwoofer performance in a small package requires a jump in price bracket (see: QSC KS212C, JTR C212pro, etc.).

I believe Jay Barracato expresses it as "+3db$"
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 10, 2019, 03:47:42 pm
I believe Jay Barracato expresses it as "+3db$"

Once again, this forum needs a like button.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Simon_Barrett on January 11, 2019, 05:45:58 pm
Just a quick question, but an important one.

What was the distance between the subs and the back wall. Could it have been approximately half wavelength of the punchy frequencies? Like around 1.5m to 2m between sub and back wall...

Causing an anti phase situation and making you think that there was little to no sub but actually it was a room acoustics thing?




Sent from my iPhone using Tapatalk
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 11, 2019, 06:01:16 pm
Good question.

No, the subs were way off the back wall, probably 15-20'. I'll repost the pic of the stage/dancefloor area below. The photo's perspective really does not give a good idea of the distance from the back wall to the stage through the dance floor to the camera position, but the stage is about 12 to 15' deep and there is about 4' of dead space between the rear of the stage and the back wall. There is a parallel to the left side of the stage but it too is at least 25' feet away. I don't think boundary cancellation was an issue at the gig noted in the OP, but at that gig we did have the PA on the stage and for the subsequent event in the photo below it was placed on the floor.

Just a quick question, but an important one.

What was the distance between the subs and the back wall. Could it have been approximately half wavelength of the punchy frequencies? Like around 1.5m to 2m between sub and back wall...

Causing an anti phase situation and making you think that there was little to no sub but actually it was a room acoustics thing?




Sent from my iPhone using Tapatalk
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Bill Hornibrook on January 12, 2019, 07:27:04 pm
I agree with many in this thread that a good place to start would be to run the system as it was designed.

Highpass mains at one frequency - rather than giving your bass an extra 10hz of low freqency extension (which I suspect could be aggravating the problem).

It's often mentioned in this forum, but center coupling subs can make a noticable difference - especially with smaller systems. Apparently there are pole mounts on the tops.

The best help would be to augment their system with your subs. Yeah I know this means transporting them youself, but I have done this countless times - even as a fill-in if the gig is important.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 14, 2019, 12:36:43 pm
I agree with many in this thread that a good place to start would be to run the system as it was designed.

Highpass mains at one frequency - rather than giving your bass an extra 10hz of low freqency extension (which I suspect could be aggravating the problem).
\

What do you mean by the bolded text? Are you referring to the channel HPF, or the out of band EQ being applied, or the system crossover itself?

The tops are high-passed (and the subs are low-passed) internally at the speaker itself.

It's often mentioned in this forum, but center coupling subs can make a noticable difference - especially with smaller systems. Apparently there are pole mounts on the tops.

I like this idea from an audio performance perspective. But center-placed subs are not likely to be an option in most venues. The F1 stack is a nice, little compact setup that only takes up 17" on each side of the stage - which pleases the clients. Many times space is tight and to place the subs centered and then add speaker stands to the equation would not work logistically nor be the aesthetic the band would want.

Ultimately that would not be my call, though.

The best help would be to augment their system with your subs. Yeah I know this means transporting them youself, but I have done this countless times - even as a fill-in if the gig is important.

I would be willing to transport my subs to gigs provided that I was adequately compensated for their use and for my driving. As it stands now the band all commutes together in the bus and shows are typically several hours drive each weekend night. So for me to go from being a passienger traveling to shows in a bus to now driving my personal vehicle hundreds of miles per gig and bringing more gear my compensation would have to go up considerably. Even then not sure I would want to do it.

Logistically for me (and the band) that doesn't really make sense. If a more powerful system is truly needed I think the band would rather invest in having that permanently on hand. And since there have not been any client complaints this whole issue is just me trying to optimize what we've got.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Dave Garoutte on January 14, 2019, 12:45:42 pm
\

What do you mean by the bolded text? Are you referring to the channel HPF, or the out of band EQ being applied, or the system crossover itself?

The tops are high-passed (and the subs are low-passed) internally at the speaker itself.


The idea is to filter out the low frequency energy the subs can't replicate.
If the subs only go to 40 hz, high pass everything below that; the amp will have more usable power and the speaker won't heat up trying to reproduce something it can't.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 14, 2019, 12:54:45 pm
The idea is to filter out the low frequency energy the subs can't replicate.
If the subs only go to 40 hz, high pass everything below that; the amp will have more usable power and the speaker won't heat up trying to reproduce something it can't.
Yes, I made that adjustment and some others. See updates below. Ironically, we have not had to push the system as hard since the gig referenced in the OP.

https://forums.prosoundweb.com/index.php/topic,169578.msg1564882.html#msg1564882 (https://forums.prosoundweb.com/index.php/topic,169578.msg1564882.html#msg1564882)

https://forums.prosoundweb.com/index.php/topic,169578.msg1564945.html#msg1564945

https://forums.prosoundweb.com/index.php/topic,169578.msg1564946.html#msg1564946
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Bill Hornibrook on January 14, 2019, 03:35:11 pm
The idea is to filter out the low frequency energy the subs can't replicate.
If the subs only go to 40 hz, high pass everything below that; the amp will have more usable power and the speaker won't heat up trying to reproduce something it can't.

Yes... and to take this a little further...

Generally the Bose Way is to take mediocre drivers, and make them somewhat presentable with extensive processing. Based on the OP's original symptoms of rattling grilles and flapping speakers but little sound, I strongly suspect that there's a brickwall HP filter for the entire full-range signal in the tops, and by aux feeding the subs you are bypassing that protection. I would run the system as designed.

Patrick if you getting better results now, that's great. But I don't think there's any way this system is going to give you the sound you are looking for from your 5 and 6 string basses. If the distance is too far to transport your subs, you'll just have to roll with it. Best of luck...
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Patrick Cognitore on January 14, 2019, 06:15:42 pm
Yes... and to take this a little further...

Generally the Bose Way is to take mediocre drivers, and make them somewhat presentable with extensive processing. Based on the OP's original symptoms of rattling grilles and flapping speakers but little sound, I strongly suspect that there's a brickwall HP filter for the entire full-range signal in the tops, and by aux feeding the subs you are bypassing that protection. I would run the system as designed.

The signal path is designed to go from mixer to subs to tops when using the whole system, so any limit/EQ/Crossover processing for the subs is in the subs, aux fed or not. My preference would be to reconfigure the system as "non-aux fed" for at least a few gigs to see how it performs, but ultimately I'm not in charge of the rig so it's not my call.

Patrick if you getting better results now, that's great. But I don't think there's any way this system is going to give you the sound you are looking for from your 5 and 6 string basses. If the distance is too far to transport your subs, you'll just have to roll with it. Best of luck...

Agreed. Rolling has commenced.
Title: Re: Bose F1 Sub, having issues. Any users have feedback?
Post by: Bill Hornibrook on January 14, 2019, 07:28:51 pm
The signal path is designed to go from mixer to subs to tops when using the whole system, so any limit/EQ/Crossover processing for the subs is in the subs, aux fed or not.


Well... there shoots my best theory as to what's going on down  ;D


Sorry Patrick - carry on as you see best.