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Title: DIY or not...?
Post by: Chris Cox on March 23, 2009, 10:48:26 pm
:disclaimer:   I aspire to one day be able to call myself a "pro", but I am currently nowhere near that goal, so please forgive any offensive ignorance on my part.  


I currently have a pretty small system, consisting of 4 Yorkville u15p tops and six Bag End d18 subs, running off 3 qsc plx1804 amps, one amp per 2 subs.  I love the yorkvilles, but I've been generally disappointed with the bag ends.  They reach really low and sound very nice at low to moderate volumes, but they just don't seem to be capable of the sort of output that I need.  

*side note, if anyone has some experience with bag end subs, and has any advice or input as to why they are so weak, please share!


So, unless someone has some really helpful advice about getting more out of the Bag Ends, i'm planning to upgrade to better subs, and I'm debating whether it would be wise to go the DIY route or not...  LAB subs are out of the question, because they are too big, probably beyond my woodworking skill level, and there are already 2 great sound providers in my area that have 6 LABs each.  I'm interested in possibly trying my hand with this:

http://www.speakerstore.nl/constructions/61

Walt's "stepped horn".  Seems like a relatively easy/affordable build, capable of some pretty nice output...but the more I research, the more I come to realize that I really have no idea if this design would make a good PA sub - even if I made 6 or 8 of them.  

The vast majority of events I do are 200-300 people, electronic music - usually DJs and occasionally live electronic, and frequently include *very* bass heavy music (dubstep, which often features silly 40hz or lower sine wave sub-bass).

My non DIY thoughts are to start with 4 growlers, with the intention of upgrading to 8 or more as cashflow allows; or start with 2 Danley TH-212s with the intention of upgrading to 4 or more as possible (though I can't seem to find a price for the TH-212, so I'm only guessing that this is in my price range).  I also have a Yorkville UCS1p, and I've considered just getting several more of those - but I'm doubtful that this would give the size to output ratio I'm hoping for.  If anyone has used the UCS1p in groups of 4 or more, please chime in.

I usually work solo, and generally need everything to fit into the back of my 4runner + a 4'x8' trailer.

I'm not at all opposed to the inevitable blood, sweat, and tears of a DIY project, but ultimately I'm first and foremost concerned with ending up with the most kick-ass system possible for the money/time/size.


Sorry about the variety of topics all mashed into one rambling post...

Chris
Title: Re: DIY or not...?
Post by: Duane Massey on March 23, 2009, 11:46:23 pm
These boxes don't seem to very efficient, and that's also an issue with the Bag Ends. I've never heard a Bag End system that sounded good at higher volume levels, but I could say the same about most vented small-footprint boxes.

I wouldn't suggest DIY unless you really want to do it for the joy (or experience) of building your own, and definitely not if you're intimidated by the Lab subs. Anything less will not exactly give you an edge on your competition, but there are many choices out there.
Title: Re: DIY or not...?
Post by: Pascal Pincosy on March 23, 2009, 11:49:48 pm
Are you using the Bag End processor with your current Bag End subs? It might make a big difference depending on the model of sub you have.
Title: Re: DIY or not...?
Post by: Chris Cox on March 24, 2009, 01:59:42 am
Pascal,

Yes, I have an ELF M2, and I have at least a basic understanding of the idea behind the ELF (now called Infra) system that Bag End uses - 3 cubic foot sealed chamber which naturally rolls off at 12db/octave on either side of 95 hz, no lo-pass filter to avoid introducing delay into the signal, "dual integrator" which creates a 12db/octave boost down from 95hz to 18hz for a "perfectly flat" response...  cool concept, and it works wonderfully in a HT or studio environment... but as a PA, I just can't seem to get the volume and impact I want - which is a damn shame, because I'd love to have the musicality, tightness and punch that the Bag Ends have in a high output PA.  

I suspect that some of my trouble is due to my less than complete understanding of boundary cancellation and other room effects (to which these subs are, as far as i know, highly susceptible.)  I wonder if these subs might perform much better in the hands of a more experienced operator, and I'm hoping someone with experience using them will chime in...
Title: Re: DIY or not...?
Post by: Dave Rickard on March 24, 2009, 02:01:46 am
I currently use BFM Tuba 30's.  I really like them...

I can't rent more.  
I can't buy more.  
If I needed more TOMORROW, no way it's gonna happen.

If your time is free (rare), you can save bucks.
Pretty forgiving construction.
If I did BFM again, I'd do Titans.

Probably going to switch to UCS1P's in the future.  
There are some threads with opinions about 4 of them.
Title: Re: DIY or not...?
Post by: Johan Diettrich on March 24, 2009, 09:05:41 am
Quote:

Walt's "stepped horn". Seems like a relatively easy/affordable build, capable of some pretty nice output...but the more I research, the more I come to realize that I really have no idea if this design would make a good PA sub - even if I made 6 or 8 of them.
Walt's stepped horn has a bit low sensitivity figure. It might actually be quite a bit lower than the Bag End's you're using now (couldn't find the right model, they all seem to go down to 8 Hz instead of 18 Hz).

You might get more output by setting the high pass higher. Below 20 Hz there is often material included that doesn't seem to be very related to the song.

I would suggest diy over buying but I'm biased. The Growlers seem like a good option but are for ~40+ Hz as are the TH-212.
The're plenty of 15" or 18", 40+ Hz diy-designs out there.
For the best money-performance ratio I would bet on diy (for bass/subs). For the best time/labor-performance either the Growler, TH-212's (or other commercial design).

For 200-300 people (inside) something in the range of two double 18" basreflex or two triple 15" could be suffic
Title: Re: DIY or not...?
Post by: Dave Rickard on March 24, 2009, 10:19:16 am
Johan Diettrich wrote on Tue, 24 March 2009 07:05

To learn more about the best placement for your subs read this (oh, and if possible against a solid wall): http://www.voidaudio.com/pdf/bass%20guide.pdf


Thanks for that link!
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 24, 2009, 11:35:16 am
Hi chris.   I read your post.  As far as labs goes one of the guys you must be talking about is andy over at edge audio?  He built those 12 labs himself took him 6 months.  I have done some engineering work for him.  The size and weight make those things obsolete these days.  Plus his were never flat to begine with but man do they hit like a mother around 63, 50 hz   You might go to harleyshouseofsound.com and see if that will help you.  I have been in your shoes and have wasted a ton of money on the jbl srx, the eaw 850's the meyer u.p  rig and finally got it figured out.   If your listening crowd is within 150 of your FOH then The jtr,s are the way to go.  plus I cant find anything that beats the growlers  I started with 4 growlers and now have 12.  I use 4 60% of the time and the other 35% I use six and 4% I use 8 and 1% i use 12.   They are the most musical for sure that is priority number one.  For size my crew consist of a bunch of teenage girls if that tells you anything (The boys dont last there pussy's that dont know how to work)  So girls lift these things all day long.  I stay busy year round so let me know if you ever want to hear them. I have gone head to head with a lot of stuff and always come out on top I guess that is why I get so much work clients can tell when you have a better rig.  Good luck  Harley
Title: Re: DIY or not...?
Post by: Art Welter on March 24, 2009, 02:22:16 pm
Chris,

Your problem is simply the inefficiency of the system you are using, the laws of physics apply to all subs.
As you mentioned the the cabs you use need 12 dB more power at 47.5 HZ to be equal in level to 95 HZ.

If it takes 100 watts to achieve 115 dB at 95 HZ, it would take 1600 watts to achieve the same level at 47 HZ, which is not all that low. If you wanted another 3 dB, you need to pump in 3200 watts, and the smoke will not be long in coming.

Proper placement is helpful, but there are plenty of cabinets available that are easily 10 dB or more efficient down low than the cabinets you are using.

10 dB sounds twice as loud.

Art Welter
Title: Re: DIY or not...?
Post by: peter.golde on March 24, 2009, 04:00:21 pm
Size and weight makes Labs obsolete? maybe for you and your small shows, but there isn't much out there that does as well in groups, and something is wrong when 12 Labs aren't flat to 32hz and only bump at 63-50hz.
Growlers are a good solution for his start-up.
For DIY, Walt's Punisher would work on top of your current subs, below the tops. 2 way bass for EDM is hard to beat. pardon the pun
Title: Re: DIY or not...?
Post by: Chris Cox on March 24, 2009, 07:36:11 pm
Johan, thanks for the great link!

and everyone else, thanks for all the insight.  So i'm leaning towards non-DIY because size is a pretty big issue for me... and it seems like 4 growlers are a pretty solid choice, particularly because it should be easy for me to arrange a listening test.  So now I'm just wondering how 4 growlers would compare to 2 Danleys (TH212 or TH115)?  Some pretty thorough searching hasn't yielded much of anything on the TH-212, other than some general comments by Ivan and Mike.  I know I can trust the Danley published specs, and they seem to indicate that the TH212 is amazing - but has anyone actually used/heard them -- and how much do they cost...?
Title: Re: DIY or not...?
Post by: Ivan Beaver on March 24, 2009, 08:51:31 pm
You can contact your local rep for pricing and ask about getting a demo.  

http://www.danleysoundlabs.com/wheretobuy.html

If the Boston get to gether comes together Rolling Eyes I am thinking about bring a TH212 there for people to play with, along with another product or two.

As a general rule the TH212 has more "punch", and slightly deeper lows (more of a listening thing than a measured thing), but the Th115 has more "meat" (40-50Hz).  The TH212 is smaller and will fit places the TH115 won't (under a shallow stage (it is 15" tall) or flat up against a wall-it is only 15" deep in that mode).
Title: Re: DIY or not...?
Post by: Chris Cox on March 24, 2009, 09:25:53 pm
After spending a good deal of time with this wonderful thread:
http://srforums.prosoundweb.com/index.php/mv/msg/41126/0/20/ 22126/

I've still got almost no idea what "punch" is, but I'm damn sure I want it Very Happy

So if I go with the Danleys, I guess I just need to figure out if I'm going to prioritize the "punch" or the "meat"...

Razz
Title: Re: DIY or not...?
Post by: Ivan Beaver on March 24, 2009, 10:12:07 pm
Chris Cox wrote on Tue, 24 March 2009 21:25

After spending a good deal of time with this wonderful thread:
 http://srforums.prosoundweb.com/index.php/mv/msg/41126/0/20/ 22126/

I've still got almost no idea what "punch" is, but I'm damn sure I want it Very Happy

So if I go with the Danleys, I guess I just need to figure out if I'm going to prioritize the "punch" or the "meat"...

Razz

As usual, program material will show off one or the other more-or not.

Sorry for the term "meat", but that is what came to mind-think closed fist when saying it Laughing

Sometimes there is very little difference in sound quality-and other times it is huge. It really depends on what is being played.

The same thing goes with subs that go really low.  Depending on the material, the differences can be amazing-then put on something that has different low freq content and there is almost no difference at all-and there is no reason to buy the sub that goes lower.

As the saying goes "it depends".
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 24, 2009, 10:23:28 pm
Small shows maybe if your talkin over 2500 to 3000 people.  These size of outdoor crowds are done nicely with only 12 growlers.  And as I said in my reply I dont think something is quit right with his set up because it definitley is not flat to 35 was there alot of bass yes was it musical no it was disperportioned.  When you have stuck a couple of growlers side by side with a lab then you can report back to me.
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 24, 2009, 10:32:07 pm
Call up Jeff he has ran across this exact question before.  He will shoot you over the grapghs so you can compare and see.  The grapgh and spec comparison goes to the growler but I have never done a side by side with the two.  And yes it all depends.  I will tell you that if you are doing anything under 50hz the growler is not the ticket.  But its so damn musical to that point it works for everything I do and always sounds low, clean and tight, Very musical.
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 24, 2009, 10:58:50 pm
The labs do group well but so do the growlers REALLY well.  Granted the labs do go to 32 (really well) I will give you that  If I was doing raves my whole life and had a truck that would fit the lab and someone elses back to lift it then yes the lab is a sure bet.  But that is not what chris is looking for.  I went that route for one season and switched to the JTR set up and my work doubled.  Yes I did not get a big hip hop show because he didnt trust the growlers but I did get wu tang and we just killed it.  And I have had one show where all there material was down past 50 but one artist and one 45 minuet set was a let down compared to over 100 artists and 1000 hours of go time.  I can handle that.
Title: Re: DIY or not...?
Post by: Jeff Bailie on March 25, 2009, 07:05:48 am
Hi Chris,

I honestly think that the TH115 is what you are looking for. They go low, they have a sensitivity of 106, and they are small.

I know what kind of music your into, and I don't think the Growler goes low enough for you. I'm pretty sure a TH115 would move twice as much air as a Growler at 35 Hertz.  

In reference the question "DIY or Not"?  Whatever you decide, Just remember that their is a Table Saw with a 54 inch fence sitting in my shop with your name on it. And also remember that there is a dude named Jeff sitting on the couch next to that shop just waiting to help you cut up all that wood.

P.S. You need to come up the hill anyways so you help me listen to these new SH50s. And you need to bring your U15s so we can A/B em.


Title: Re: DIY or not...?
Post by: Harley Osterlund on March 25, 2009, 09:38:48 am
Hey Jeff this is Harley.  Chris told me you live up by horsetooth.  Would love to get with you sometime and do some comparisons.  I talked with chris at length about material below 50hz and what the growlers will and wont do.  I think he is going to come over this weekend for a demo.  Maybe I can talk you to coming down with some of your toys and will hook them up to the i-tech 6000 and wake up my neighbors LOL.   Harley
Title: Re: DIY or not...?
Post by: Dave Rickard on March 25, 2009, 10:40:40 am
Maybe it's time for a Front Range Lab listening party!  There are a handful of us out here.

Anything I own would be available.  U15P's and Tuba30's would fit this event.
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 25, 2009, 10:54:07 am
Lets do it!!!   Then there will finally be a real report people can put there teeth into.  I will bring the growlers and if I can talk jeff into it I will have jeff send me an ambassador for when you guys start playin all that 35 hz stuff on me LOL!!
Title: Re: DIY or not...?
Post by: Chris Cox on March 25, 2009, 12:15:27 pm
A front range shootout sounds like it would be a blast, we should do it.  

...and (pending some listening tests)I'm feeling more and more like I should get the Danleys, if only to be different  Very Happy

speaking of which, looking at the specs on the th115 and th212, their range is up to 200hz, though obviously in normal use the crossover would be much lower, 80-100 i'd guess.  forgive if this is painfully ignorant, but would it be possible, give an scenario where some months down the road I do decide to build a bunch of LABs, to use the th115s or th212s for midbass above the LABs for large shows?  My numbers are just guesses, but something like have the labs handle 30hz-60hz, the Danleys handle 60-110.  And now that I think about it, the growlers could also work in this way... right?  Or is there some fundamental difference between subs and boxes specifically designed for mid-bass that I don't know about?
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 25, 2009, 12:48:09 pm
No you could certainley do that but the growler cuts out drastically from 125 up  But from 50 to 125 it owns it.  Bring some tops over with you from horsetooth jeff as well we will match them to the triple 12 and see what the scoop is.  BY the way Jeff also makes a box called the ambassador that is a 30 to 80 type of thing I know it beat out the danleys when we compared them.
Title: Re: DIY or not...?
Post by: Ivan Beaver on March 25, 2009, 01:11:54 pm
When you start to mix cabinets and operate them over a limited range (1 octave) it can be really hard to get them to mesh together-phase-amplitude etc.

It would be better to get a single device to cover the range.
Title: Re: DIY or not...?
Post by: Patrick Tracy on March 25, 2009, 02:24:12 pm
Thanks for the PM, Dave. Anything I have is also available if it's not in use at a gig. I have a pair of Celestion SR2 bandpass cabinets which may provide a useful point of comparison.

Given our location we could probably find a ranch or the like where we could do outdoor tests. Does anyone have SMAART and a decent measurement mic? I have one of the Behringer mics and some freeware, but that's probably too ghetto to do it right. I think it would be good to do some real measurements so it's not all subjective.
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 25, 2009, 09:35:47 pm
I agree let me look into it but I think I got a buddy with smart I will give him a jingle.  I can also bring the kick drum and a bass rig for real world applications for running band gear so its not all program material.
Title: Re: DIY or not...?
Post by: Jeff Permanian on March 25, 2009, 09:39:53 pm
Harley Osterlund wrote on Wed, 25 March 2009 09:54

 I will have jeff send me an ambassador for when you guys start playin all that 35 hz stuff on me LOL!!
Captivator!!
Title: Re: DIY or not...?
Post by: Harley Osterlund on March 25, 2009, 10:24:48 pm
LOL!! My bad the captivator  I get them confused
Title: Re: DIY or not...?
Post by: jeffhtg (Jeff Kenney) on March 27, 2009, 10:33:20 am
Harley Osterlund wrote on Tue, 24 March 2009 15:35

 they hit like a mother around 63, 50 hz  


And they hit like a mother at 35 hz, and 40hz, and 55hz, and 70hz.. The lab is a really good sounding and good responding box for what it is. I would definitely  not say that their size makes them obsolete as most big super subs out there take up a bunch of space.

I have yet to hear the TH215 and I anxiously wait for the day I can go do a subjective listening test with Ivan. I can tell you the 115 is not a great candidate for electronic music. I'm not sure what it is.. and I think I saw Ivan talk about this before. The "pant flap" factor just isn't there with the 115. It is a great sounding sub - but just doesn't do it for me on the ULF.

I hope to hear growlers some day as well.. a lot of talk on these but I just can't believe they are as awesome as everyone says until I hear them.

So once again I will default back to my favorite subs for dance.. Martin WSX, Martin sb218, EAW DC2, EV QRX218, L'acoustics sb218, and the new bassmaxx stuff is pretty neat (check out ultra's stage this year - they are after all the largest dance show in the US).

Edit* another thing that might be an issue is your 18xx series amps.. I've never used those before and I believe they are a class AB amp. I'm assuming your bridging them.




Title: Re: DIY or not...?
Post by: Harley Osterlund on March 27, 2009, 11:01:48 am
I hear what you are saying.  By obsolete I am talking about my world.  I dont do anything above 5000 people.  And all the other small company's like me are looking to the future smaller, lighter, faster, tighter and more musical.  If some one just handed me six or 12 labs I still would not use them for my application.   Now if I had an install to do I would definitly consider it.   And if I owned a sporting arena then you better believe it LOL!!!

   I was a huuuuug skeptic.  I called and talked jeff's ear off for hours and months before I had him send me out a growler.   We got it off the fed ex truck and A/B it with an EAW 850 2x18 cab at 4 ohms with the PL3000 drivers in it (still my favorite sounding 18)   The growler was 8 ohms we didn't change a thing.  Just un-plugged from the EAW and into the growler.  And no matter what material we ran, the growler was undisputable.  We then ran kick drum through the two cabs, and bass, guitar again there was no denying what we heard.

    I am hoping to get together with these cats and do a super huuuge ROCKY MOUNTAN front range shoot out.  We got a cat bringin in the labs, and another one bringin in some Danely stuff.  I will let you know what we find.

                 Cheers, Harley

Title: Re: DIY or not...?
Post by: jeffhtg (Jeff Kenney) on March 27, 2009, 07:20:06 pm
You will find the Danleys to be a bit more musical - they sound more front loaded than horn. The labs will go lowers and give you much more pant flap in the lower end where most of our dance bass resides.  The Danleys are much more efficient. I don't like the labs unless you have a big amp on them. (pl328, vz5000, etc)
Title: Re: DIY or not...?
Post by: Jeff Bailie on March 29, 2009, 11:52:01 pm
I am always down with a listening.  After every show we set up the whole system in my basement.  Soon it will be warm outside, Then Id be glad to drag it out in the woods. In fact, this summer it will pretty much live in the woods!


PM me if your in the Fort Collins area and I would be glad to give any one a demo.   We use the system everyday at low levels and the neighbors never complain.    


Thanks again to Tom Danley. I feel like I can never say that enough.  

Here is a shot of the current setup in the basement. We listen to a lot of very chill music. Everyone fights for the center of the stereo spectrum.
Title: Re: DIY or not...?
Post by: Jeff Bailie on March 29, 2009, 11:58:31 pm
Last week.  

The goal is to try and find the right Balance between the tops and subs, All while trying to keep the house from rattling.


Title: Re: DIY or not...?
Post by: Chris Cox on April 01, 2009, 06:26:24 pm
I've been trying for a week now to find a Danley dealer somewhere in my part of the country, and have had no luck.  I've tried the "where to buy" link that Ivan suggested, which, by way of a marketing firm, ended up leading to (what appears to be ) an A/V install contractor - left a message and called several times, no answer, no return call.

Does anyone here know of a Danley dealer anywhere in/near Colorado?

I'm in Fort Collins, but I'm willing to go pretty much anywhere in Colorado if I need to...

thanks,

Chris
Title: Re: DIY or not...?
Post by: Tom Bourke on April 01, 2009, 08:50:26 pm
I have worked with the Bagends and I think you have the wrong amp.  I don't think PLX1804 is enough power for them.  It is just on the edge so when you push it the amp starts to run out of power (my guess is current limiting right when you need it.  Try your subs on a set of PLX3602 or better.  One install I worked on had 9 18" drivers per side on 3 PLX3402.  I could make you think the earth was moving.  I also used them in smaller systems.

BTW are you hitting the threshold on the protection in the infra?

I don't think I would buy them now.  I think the trade off you give for such low end is the harmonic distortion.  I had a large gap between the subs and tops to make room for it. It was a nice system to mix on once I had it tuned in tho.
Title: Re: DIY or not...?Clarification please
Post by: Ivan Beaver on April 01, 2009, 10:12:49 pm
Tom Bourke wrote on Wed, 01 April 2009 20:50

  One install I worked on had 9 18" drivers per side on 3 PLX3402.  I could make you think the earth was moving.  I also used them in smaller systems.


I don't think I would buy them now.  I think the trade off you give for such low end is the harmonic distortion.  I had a large gap between the subs and tops to make room for it. It was a nice system to mix on once I had it tuned in tho.


OK I am confused.  Am I reading you right in that you are running 9 drivers per side of the amp?  Did you do a series parallel configuration (if so what combination) or straight parallel?

Are you also saying that you leave a gap in the freq response between the subs and the mains? To allow for the distortion components in the subs to "fill in"?????


If so-what about the instruments whose fundamental falls in the freq range that you have "vacant"?  What are they reproduced by?

Maybe I am just reading this wrong Rolling Eyes
Title: Re: DIY or not...?Clarification please
Post by: Tom Bourke on April 01, 2009, 11:39:05 pm
Sorry I should have been more clear.

It was 3 amps with 3 drivers per CH for subs.

As for the the "gap" the system used the bagend processor to split between the mains and subs.  The mains then went into a DSP.(EV DSP and Deltamax 1183 mains)  I think I ended up with the HP on the mains up around 150 or so, maybe a little higher.  That was 7 years ago.  The bagends claim to roll off naturally above 95 Hz.

I did not have any measurement equipment other than my ears and lots of CD's and time mixing on the rig.  With out that gap the system had lots of low mid mud. I attributed it to the harmonic distortion in the Bagends.  Since there was nothing I could do about it I decided to raise the HPF on the mains to reduce the overlap.  It sounded better and was MUCH more tame to mix on after that.  

Looking back with what I know now I would have done things different. But it worked at the time.  I still think those subs had a bit too much garbage out of band.  However given that the OP likes the sound of his rig at low volume and that his sub amps are at the very edge I would try some more powerful amps there first.  I think he will need them any way.

Edit:  I think maybe this was one of those systems where the electronic XO and the acoustic XO were different due to the 12 dB roll of of the sub and the relative levels of the mains and subs.
Title: Re: DIY or not...?Clarification please
Post by: Chris Cox on April 02, 2009, 12:58:33 am
Tom,

Thanks for the input.  I bought the 1804s specifically on advice from someone at bag end - they recommended not overshooting the rated power handling of the drivers by too much - on the spec sheets it says that the continuous sine wave and instantaneous peak are the same - 800 watts.  I believe this has to do with it being a sealed chamber?  They said an amp that would deliver 900 watts to each dual 18 cab (450 per driver) would work well, particularly given that most of the stuff i do is highly compressed, bass heavy electronic music.  And while I do think that the bag ends sound very nice at low volume, as soon as you start pushing them you end up with a lot of distortion.  And even if I could get a bit more output with larger amps, I just don't think the bag ends have the efficiency, or output to size ratio that I need.  I'm sure I could get a bag end system to rock pretty hard given enough cabinets, but I don't really want to have to lug 10 or 12 dual-18 cabs to every show Sad

speaking of amp power...

I'm wondering about how I should be planning amp power for new subs.  I've done a good bit of reading, many threads, about appropriate power matching between amps and speakers, but in most cases these refer to live sound applications.  Most of the shows I do will be DJ/Laptop live electronic, where the material is very (over)compressed, and is almost always going to have a good bit of (compressed) sine wave sub-bass in the 30-50 Hz range.  So I'm pretty confident that the normal "rules of thumb" are not going to apply...  My thoughts are currently to split the difference between the continuous and program, and make sure I never see the clip lights.  For example, with 4 TH-212s, use two crown xti6000 amps, one sub per amp channel, and so be able to provide 2100 watts to each 4 ohm TH-212.  Does this sound good, or would that still run a significant risk of blowing things up (give the nature of the program material)?

and what the hell, while i'm at it:  Are there significant drawbacks to using amps in 4-ohm bridge mono mode / 2 ohm stereo mode?  I ask because looking at price to output, if the goal is to power 4 TH-212s with around 2000 watts each, getting 4 XTi2000s, at around $600 each, one amp bridge mono 4-ohms per sub, versus two XTi6000s, at around $2k each, one sub per amp channel stereo 4-ohm... it doesn't seem that the extra 100 watts per sub would be worth the $1,600 price difference... but I'm sure there are factors I am ignorant of.

(btw, I'm not set on using XTi amps, they just have good numbers for my examples, I welcome amp recommendations and suggestions.)

also, ignore my previous post, got a call from Joel at Danley today, they are helping me figure things out with finding a dealer Smile  
Title: Re: DIY or not...?Clarification please
Post by: Ivan Beaver on April 02, 2009, 08:08:32 am
You will never notice a difference of 100 watts at the 2000 watt level.

I prefer the sound (in general) of an amp run in the stereo (or dual mono-whatever) over one run in bridge mode.  But that can vary from amp to amp.

You should be fine with the TH212's and 2000watts @ 4 ohms-just don't tickle the clip lights to much.

Be sure to run a high pass filter to keep the crap out of the subs-but you should do that on any loudspeaker.
Title: Re: DIY or not...?Clarification please
Post by: Harley Osterlund on April 02, 2009, 09:44:07 am
When you find your Danley dealer let me know I will send you to them with 4 growlers that way there is no guess work as to what works best for your app.  Cheers  Harleys house of sound
Title: Re: DIY or not...?Clarification please
Post by: Jeff Permanian on April 07, 2009, 03:33:08 pm
Always read manufacturer specs carefully. The most fraudulent claims I'm seeing lately is peak output ratings calculated from a 2.83 volt sensitivity measurements and peak power handling. A 2 ohms speaker consumes 4 watts at 2.83 volts which 6 db over a 1 watt measurement which is fine because it is listed as a 2.83 volt measurement however the deception come from adding the gain from peak power handling to this number. If a 2 ohm speaker is 112db at 2.83 volts and is capable of consuming 8000 watts (39db of gain) then its peak output is 145db (NOT 151db).