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Title: VRX compression driver alternatives
Post by: Dennis OShea on March 15, 2014, 03:43:25 PM
Hi all
has anyone tried  different compression drivers on the VRX cabinets.  I find the 2407 drivers quite harsh and not at all musical. They sound especially awful and unnatural on vocals.   I am not concerned with the internal passive crossover.  I guess you get what you pay for.
Thanks 
Title: Re: VRX compression driver alternatives
Post by: Tim McCulloch on March 15, 2014, 04:20:48 PM
Hi all
has anyone tried  different compression drivers on the VRX cabinets.  I find the 2407 drivers quite harsh and not at all musical. They sound especially awful and unnatural on vocals.   I am not concerned with the internal passive crossover.  I guess you get what you pay for.
Thanks

How are you currently processing?
Title: Re: VRX compression driver alternatives
Post by: Art Welter on March 15, 2014, 04:29:49 PM
Hi all
has anyone tried  different compression drivers on the VRX cabinets.  I find the 2407 drivers quite harsh and not at all musical. They sound especially awful and unnatural on vocals.   I am not concerned with the internal passive crossover.  I guess you get what you pay for.
Thanks
If you are using the internal passive crossover, it is designed for the drivers on the VRX horns, substituting drivers will require a crossover change.

A few properly placed sharp notches will eliminate most of the 2407 problems.
Title: Re: VRX compression driver alternatives
Post by: Bob Leonard on March 15, 2014, 04:45:55 PM
If you are using the internal passive crossover, it is designed for the drivers on the VRX horns, substituting drivers will require a crossover change.

A few properly placed sharp notches will eliminate most of the 2407 problems.

+1. Easy peasey.
Title: Re: VRX compression driver alternatives
Post by: Dennis OShea on March 15, 2014, 04:58:35 PM
How are you currently processing?

Hi Tim - DBX 4820 / Crown Itech with JBL tuning.
Title: Re: VRX compression driver alternatives
Post by: Samuel Rees on March 15, 2014, 05:19:21 PM
How many boxes, curiously?
Title: Re: VRX compression driver alternatives
Post by: Art Welter on March 15, 2014, 05:36:04 PM
Hi Tim - DBX 4820 / Crown Itech with JBL tuning.
Dennis,

What are those tunings?
Have you confirmed that the amp(s) are actually set to the tuning settings?

Art
Title: Re: VRX compression driver alternatives
Post by: Art Welter on March 15, 2014, 05:40:30 PM
Dennis,

What are those tunings?
Have you confirmed that the amp(s) are actually set to the tuning settings?
Have you measured the response of individual drivers to verify all are working, and none have rubbing voice coils?

Art
Title: Re: VRX compression driver alternatives
Post by: Dennis OShea on March 15, 2014, 07:40:56 PM
Dennis,

What are those tunings?
Have you confirmed that the amp(s) are actually set to the tuning settings?

Art
 Sorry my message was a little unclear.  All tuning are done in the 4820.  The I-tech's are the system amps with clip limiters engaged.  The settings are JBL presets in the 4820.
Title: Re: VRX compression driver alternatives
Post by: duane massey on March 16, 2014, 01:14:12 AM
I have rarely found factory tunings to be exactly what I want. Great starting place, but minor tweaks are nearly always needed.
Title: Re: VRX compression driver alternatives
Post by: Ray Aberle on March 16, 2014, 09:49:53 AM
I have rarely found factory tunings to be exactly what I want. Great starting place, but minor tweaks are nearly always needed.
Hmmmmm, I find pretty much the precise absolute opposite to be the case. I hold absolutely no delusions that I might be able to tune my system(s) better then the experts at JBL can. Why was "No JBL VerTec" showing up on system riders, and why did JBL lock down the crossover settings starting with the v4 VerTec presets so that they cannot be adjusted?

-Ray
Title: Re: VRX compression driver alternatives
Post by: Ivan Beaver on March 16, 2014, 10:12:23 AM
Hmmmmm, I find pretty much the precise absolute opposite to be the case. I hold absolutely no delusions that I might be able to tune my system(s) better then the experts at JBL can. Why was "No JBL VerTec" showing up on system riders, and why did JBL lock down the crossover settings starting with the v4 VerTec presets so that they cannot be adjusted?

-Ray
As usual-the REAL answer is "it depends".

1: It depends on what the factory says is "right".  Is it a flat response (the way I do it-so the operator has a "white canvus" to paint his musical image on) or does it have a "taper"?  That could be a falling high end or it could be a Flecther-Munson compensator so that it sounds "better" but not accurate.

2: The only way you would get the same results as the factory is to use the product in the same way.  In most cases this means outside with no reflections.

As soon as you put the product in a room-things start to change and often times need to be "compensated for".

Now granted some parameters should never be changed-but there are a number "voicing" things that can be changed to make a particular product better in a particular situation.

Move the same product to a different room-and now different things need to be adjusted.  Things like mounting height-aiming angle-proximity to reflective surfaces and so forth can really change the "tonal" character of a loudspeaker.

Of course there are some things you can adjust and make it better-and some things you cannot. 

And then there is the whole-do I make it better for 1 listening position or a average across the room?

What is most important?

There is no "one answer" or "preset" that fits all cases.

Title: Re: VRX compression driver alternatives
Post by: Jim McKeveny on March 16, 2014, 10:37:03 AM
Could you be possibly looking at the wrong end of this chain? If hashy/spikey content is entering open vocal mics, a compression driver changeover isn't the cause or remedy.



Title: Re: VRX compression driver alternatives
Post by: jason misterka on March 16, 2014, 11:27:52 AM
As usual-the REAL answer is "it depends".

1: It depends on what the factory says is "right".  Is it a flat response (the way I do it-so the operator has a "white canvus" to paint his musical image on) or does it have a "taper"?  That could be a falling high end or it could be a Flecther-Munson compensator so that it sounds "better" but not accurate.

2: The only way you would get the same results as the factory is to use the product in the same way.  In most cases this means outside with no reflections.

As soon as you put the product in a room-things start to change and often times need to be "compensated for".

Now granted some parameters should never be changed-but there are a number "voicing" things that can be changed to make a particular product better in a particular situation.

Move the same product to a different room-and now different things need to be adjusted.  Things like mounting height-aiming angle-proximity to reflective surfaces and so forth can really change the "tonal" character of a loudspeaker.

Of course there are some things you can adjust and make it better-and some things you cannot. 

And then there is the whole-do I make it better for 1 listening position or a average across the room?

What is most important?

There is no "one answer" or "preset" that fits all cases.

Ivan -

Just curious. In the examples above, wouldn't that be better if dealt with using input EQ?   Don't you want the preset based on outside, no reflections, and then you use the input eq to adjust for room and temperature conditions, array size, etc.

Though don't get me wrong, I've had my share of disagreements with factory decisions.  I've seen examples of where factory techs made real mistakes, some obvious without listening (by looking at the preset on the factory processor vs their published preferred settings) and some by listening (wow they must have set the amp gains incorrectly between bands on the PLM presets).  I've seen several examples where factory presets had entirely incorrect limiter settings or other examples of where they didn't dot their Is and cross their Ts.

Jason
Title: Re: VRX compression driver alternatives
Post by: duane massey on March 16, 2014, 11:39:12 AM
Why would you use input EQ's to adjust for environmental issues? I use input EQ's for input adjustments.
Ivan pretty much covered everything much better than I could.
Title: Re: VRX compression driver alternatives
Post by: jason misterka on March 16, 2014, 12:11:40 PM
Why would you use input EQ's to adjust for environmental issues? I use input EQ's for input adjustments.
Ivan pretty much covered everything much better than I could.

Sorry, I was referring to input eq on the system processor. Not the channel eq on the inputs.  I can see how that would be misinterpreted.

Jason
Title: Re: VRX compression driver alternatives
Post by: Doug Fowler on March 16, 2014, 01:01:26 PM
Hmmmmm, I find pretty much the precise absolute opposite to be the case. I hold absolutely no delusions that I might be able to tune my system(s) better then the experts at JBL can. Why was "No JBL VerTec" showing up on system riders, and why did JBL lock down the crossover settings starting with the v4 VerTec presets so that they cannot be adjusted?

-Ray

VerTec, and every other vertical array that appeared about that time (excluding V-DOSC) suffered the same problem: each implementation sounded different because it wasn't locked down.  I remember sitting in on a meeting with a major player, it was decided that users would be allowed maximum flexibility.  It turned out to be a mistake, IMO.

Even KF 850 had this problem after everyone got off the analog controllers and moved to DSP. Suddenly, you didn't know what you would get, sound-wise.

As pissed as many people were initially with the V-DOSC business model in the US, Jeff was right all along.  The logical extension, which is now quite practical, is the self-powered loudspeaker. 
Title: Re: VRX compression driver alternatives
Post by: Ray Aberle on March 16, 2014, 01:23:20 PM
VerTec, and every other vertical array that appeared about that time (excluding V-DOSC) suffered the same problem: each implementation sounded different because it wasn't locked down.  I remember sitting in on a meeting with a major player, it was decided that users would be allowed maximum flexibility.  It turned out to be a mistake, IMO.

Even KF 850 had this problem after everyone got off the analog controllers and moved to DSP. Suddenly, you didn't know what you would get, sound-wise.

As pissed as many people were initially with the V-DOSC business model in the US, Jeff was right all along.  The logical extension, which is now quite practical, is the self-powered loudspeaker.
And I was referring to crossover settings, of course, not specific room EQs. (Seemed like the comments were focusing later on EQs, which wasn't what I was thinking when I wrote the post.)

-Ray

Title: Re: VRX compression driver alternatives
Post by: Matthew Knischewsky on March 16, 2014, 01:26:38 PM
Hi Dennis,

We have quite a few of the first version un-powered VRX 932 with 2407 drivers in inventory. I've never tried to change out those drivers but I'll share a few of my experiences. They either go out powered and processed with Crown Macrotech 4x3500 amplifiers OR powered by bridged QSC PLX 3102 or 3002 amplifiers, with DBX DR260 processors or occasionally Ashly Protea processors.

First off, there's 2 different versions of the VRX932 but JBL doesn't go out of their way to inform users of this. The first run is the VRX932LA which uses 3x 2407, and the current version 932LA-1 which uses 3x 2408. The presets that I've found to use in our Crown Macrotech 4x3500 amplifiers are for the LA-1 version and makes our LA models all sound very bright and harsh unless EQ is applied. One work around I've found is to use DSP settings for one size smaller array than I'm actually using. For example I use the 1 box setting when I'm actually using 2 boxes per side.

Appropriate use of the attenuator settings is absolutely necessary, and here's some observations based on running these cabinets with a Driverack 260 and QSC amps. The 0db setting needs some cut around 2-4k, but the -3db setting would need a boost to the top end. Our "normal" set-up is to run the bottom box in the array -3 and any other boxes 0db. I never use the +3 setting unless the distance I'm trying to hit is over 100' away, normally in a 4 box array.

Finally, VRX932s don't get that loud in my experience. When I start to hear the vocals getting harsh I know I'm at the threshold of what the box can do. It can't be eq'd out, I think it's the HF drivers breaking up. It's still pretty loud, it's just not in your face loud like our EAW KF750s are. Or like a JBL 2450 HF driver.

Over all we have had a lot of success with the VRX932s but knowing their limitations is important. We have had some blown up but in most cases it was either not enough rig for the gig or wrong rig for the gig.

Matt.
Title: Re: VRX compression driver alternatives
Post by: Tim McCulloch on March 16, 2014, 01:48:02 PM
Dennis,

What are those tunings?
Have you confirmed that the amp(s) are actually set to the tuning settings?

Art
 Sorry my message was a little unclear.  All tuning are done in the 4820.  The I-tech's are the system amps with clip limiters engaged.  The settings are JBL presets in the 4820.

See Matthew K's post.  I suspect the preset version for your Driverack/speaker model is part of the problem, and reinforce what he says about the box itself.

It's a relatively "small box" in terms of output, and I sat through a gospel event with 4/side 932 over 2/side 728 subs.  In a 3000 capacity room.  It sounded like a bunch of small boxes being pushed really, really hard.  As things got louder it developed the icepick in the forehead sound that JBL had tried to be rid of for 20 years, but it was the result of Not Enough Rig for the GigŪ and some bad choices by the operator.  I was the electrician, I just had to wait it out...
Title: Re: VRX compression driver alternatives
Post by: Matthew Knischewsky on March 16, 2014, 01:49:03 PM
And I was referring to crossover settings, of course, not specific room EQs. (Seemed like the comments were focusing later on EQs, which wasn't what I was thinking when I wrote the post.)

-Ray

Doug has really touched on something important here because sometimes the DSP settings are really quite good (like the ones in EAW's UX8800 and the V5 VerTec settings) but others are simply base line suggestions (I'm thinking JBL settings for DR260 and 480) and yet others are what seem to be detailed EQ and X-over settings but don't work because of differences between models of processors. Doing your homework is important here and knowing when it's appropriate to stray from the manufacturer's settings and why you might have to is the hard part. Now we are getting settings derived from the manufacturer actually setting up systems and measuring them and tweaking them, where as earlier settings seemed to be an afterthought. 
Title: Re: VRX compression driver alternatives
Post by: Ivan Beaver on March 16, 2014, 01:57:12 PM
Ivan -

Just curious. In the examples above, wouldn't that be better if dealt with using input EQ?   Don't you want the preset based on outside, no reflections, and then you use the input eq to adjust for room and temperature conditions, array size, etc.

Though don't get me wrong, I've had my share of disagreements with factory decisions.  I've seen examples of where factory techs made real mistakes, some obvious without listening (by looking at the preset on the factory processor vs their published preferred settings) and some by listening (wow they must have set the amp gains incorrectly between bands on the PLM presets).  I've seen several examples where factory presets had entirely incorrect limiter settings or other examples of where they didn't dot their Is and cross their Ts.

Jason
Yes the "voicing" should be done on the input side.

And yes-people do make mistakes.

But not just at the factory level.

I have seen systems tuned by some of the "best and most respected" in the business-that were obviously wrong.  The left side doesn't sound like the right side---------

So yes-it depends. 

But I would not make a blanket statement like "all factory presets need adjustments" and also "do not adjust the factory presets".  Situations vary.

Different manufacturers have different ways of dealing with it.  Some rely soley on external processing-in which all sorts of errors could be made by the user-many of whom "think" they know more than factory-but have no way to prove it.

Others make the box sound very good by itself-so it is a lot harder to screw up externally.

Title: Re: VRX compression driver alternatives
Post by: Doug Fowler on March 16, 2014, 08:02:06 PM
Doug has really touched on something important here because sometimes the DSP settings are really quite good (like the ones in EAW's UX8800 and the V5 VerTec settings) but others are simply base line suggestions (I'm thinking JBL settings for DR260 and 480) and yet others are what seem to be detailed EQ and X-over settings but don't work because of differences between models of processors. Doing your homework is important here and knowing when it's appropriate to stray from the manufacturer's settings and why you might have to is the hard part. Now we are getting settings derived from the manufacturer actually setting up systems and measuring them and tweaking them, where as earlier settings seemed to be an afterthought.

Well, I suppose my point is in the beginning with DSP xovers, in many cases the manufacturers' settings were in fact not that good.   But in fairness, it was a steep learning curve for all involved. 

It's much better these days.
Title: Re: Getting Back To OP Question...
Post by: Jim McKeveny on March 17, 2014, 07:40:42 AM
IIRC the JBL 2407 is a BMS manufactured ring-radiator with a polyester diaphragm. In my experience with JBL models using these, there are one or two very tame-able peaks in the response (to my taste mind you, not to my analysis software).

If the OP routinely has difficulty achieving good results with unpowered VRX he needs to examine the whole system, environment, talent, and even his own expectations.
Title: Re: VRX compression driver alternatives
Post by: Jim McKeveny on March 17, 2014, 10:11:23 AM
about that time (excluding V-DOSC) suffered 

V-DOSC presets were very "young" then also. It seemed they were stressing the "cheese wedge/pie slice" HF transfer a bit too much. They also (correctly) demanded proper amplification.

L'Acoustics did keep up with it. As of now they probably have the best extended database(s) on their offerings. (Ex V-DOSC Paul Baumann w/JBL a tie perhaps?)