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Title: Alternative to Driverack PA
Post by: Joe Spitzer on March 27, 2011, 06:09:19 PM
Currently have an old Driverack PA on a JBL Sound Power rig. Generally I have been happy with it as it does everything (and more) than I need (basically I just use a little eq & the xover). However I have found that it is not hard at all for signal to blow past the limiters and clip the amps. Although the rig is great, the gain structure is set so that the average level is just below amp clipping in order to achieve the desired volume in the room. Obviously this leaves not much headroom for snare & kick hits (or anything for that matter). I have expressed that the club might invest in more power or speakers, but that is not an option at this point.

So best thing I can come up with is to try and sell the DRPA and look into a different DSP with a similar price range but with a more brick wall limiter. I have lurked around and found suggestions for the BBE ds26, and Xilica XD series (although I'm not sure what the price range of those units are) for similar situations. Thoughts?

Thanks!! 
Title: Re: Alternative to Driverack PA
Post by: Tim McCulloch on March 27, 2011, 06:13:48 PM
Currently have an old Driverack PA on a JBL Sound Power rig. Generally I have been happy with it as it does everything (and more) than I need (basically I just use a little eq & the xover). However I have found that it is not hard at all for signal to blow past the limiters and clip the amps. Although the rig is great, the gain structure is set so that the average level is just below amp clipping in order to achieve the desired volume in the room. Obviously this leaves not much headroom for snare & kick hits (or anything for that matter). I have expressed that the club might invest in more power or speakers, but that is not an option at this point.

So best thing I can come up with is to try and sell the DRPA and look into a different DSP with a similar price range but with a more brick wall limiter. I have lurked around and found suggestions for the BBE ds26, and Xilica XD series (although I'm not sure what the price range of those units are) for similar situations. Thoughts?

Thanks!!

There isn't Enough Rig for the Gig­™.

Is the peak clipping damaging the speakers?  Is the clipping sustained?

What makes you think any processor in the same price range will be demonstrably better than the DR?
Title: Re: Alternative to Driverack PA
Post by: Joe Spitzer on March 27, 2011, 06:27:30 PM
There isn't Enough Rig for the Gig­™.

Is the peak clipping damaging the speakers?  Is the clipping sustained?

What makes you think any processor in the same price range will be demonstrably better than the DR?

Hey Tim, thanks for the reply.

Since I have been working there the clipping has not damaged any speakers *fingers crossed* although I have heard stories about past engineers going through drivers like no one's business. The clipping is always just peak clipping and never sustained, and I should mention that the clip limiters on the amplifiers are engaged.
I definitely understand the price situation wont get me very far in quality (I would obviously take a DR260 any day), just was thinking that with a variable attack/release the limiters on the other units would *possibly* be more beneficial. 

Thanks!
Title: Re: Alternative to Driverack PA
Post by: duane massey on March 28, 2011, 12:56:53 AM
BBE and Behringer would not be any improvement. Not certain that a 260 would either. Possibly check out the Symmetrix Jupiter series, I've used them on three installs now and have been very pleased with the features at the price point.
Title: Re: Alternative to Driverack PA
Post by: Gary A. Perrett on March 28, 2011, 10:22:42 AM
Currently have an old Driverack PA on a JBL Sound Power rig. Generally I have been happy with it as it does everything (and more) than I need (basically I just use a little eq & the xover). However I have found that it is not hard at all for signal to blow past the limiters and clip the amps. Although the rig is great, the gain structure is set so that the average level is just below amp clipping in order to achieve the desired volume in the room. Obviously this leaves not much headroom for snare & kick hits (or anything for that matter). I have expressed that the club might invest in more power or speakers, but that is not an option at this point.

So best thing I can come up with is to try and sell the DRPA and look into a different DSP with a similar price range but with a more brick wall limiter. I have lurked around and found suggestions for the BBE ds26, and Xilica XD series (although I'm not sure what the price range of those units are) for similar situations. Thoughts?

Thanks!!

Not enough rig for the gig .1+

Limiting threads come and go a lot here, If your looking for limiting to save your system your not going to find it in a cheap processor. Your best bet is a good gain structure and leave the limiter for "oops" protection.

If you set yourself up so that the mixer is at clip just before the amps you KNOW when your out of gas.. so to speak.

Other than the BBE most other processors are at least twice the price of the DRPA, and are more than the 260( or in the same ballpark) Even the XP2X4 is about the same price as the 260, the XD is well over the $1000 mark...
best reagrds
G
Title: Re: Alternative to Driverack PA
Post by: Chris Van Duker on March 30, 2011, 03:34:27 PM
Whether you call it Not Enough Rig for the Gig, or Not Enough Babysitter for the Rig, I think it should be possible to protect things adequately, and in my experience with the Driverack PA and 260, the latter has much better limiting. Considering that the 260's come up used for $500 or less pretty often, I think it would be a smart upgrade -- the cost of a couple recones.

Or... this will be a bit controversial... I even like the limiter in the Behringer DCX2496 better than in the DriveRack PA. Buy two, and you'll still be under the price of a DR260, and you'll have a backup. (FWIW, I've had two different DR260's go titsup in the heat of battle, while I haven't lost a DCX2496 yet.)
Title: Re: Alternative to Driverack PA
Post by: Dave Bigelow on March 30, 2011, 05:58:08 PM
If I remember right it was brought up on the old forum a few times that the DRPA has "soft" limiters, they still let some through. I would try tightening them up a bit along with resetting the gain structure to where console clip is amp clip. Like someone else said, then you know you are out of gas and it should save you a few drivers in the long run.

edit: Of course 9 times out of 10 a little flicker of some red never hurt anybody. Don't get too stingy.
Title: Re: Alternative to Driverack PA
Post by: Joe Spitzer on March 31, 2011, 03:05:28 AM
Thanks for all the reply's!

I checked out the Jupiter series, and I like how it is all accessed via computer.. keeps those who shouldn't be there out of the processing! However it still won't happen due to the cost.. will definitely check out the Behringer unit, and maybe keep an eye out for a used 260.

Thanks for the suggestions of gain structure, that will be a very handy way of monitoring everything without walking back and forth to the amplifiers.

For the meantime, I have inserted a Behringer MDX1600 stereo comp between the DRPA and the Mid amplfiers, as those are the ones clipping the most, and that has seemed to help a ton. Every once in a while a transient will clip, but for the most part lights are in the green.

What is interesting however is that one of the Mid amps clips 6 or so dB sooner, and only clips on the right channel (it is run Bridged mono). I assume this is due to heat, but that's for a future discussion.... Thanks again!
Title: Re: Alternative to Driverack PA
Post by: Dave Bigelow on March 31, 2011, 08:33:38 AM
You know if you hold the wizard button in while powering up the DRPA you can lock the front controls. Of course anybody else that knows that trick only has to do the same to unlock them.

Thing is, you'll know since they will have to kill the PA to do it.
Title: Re: Alternative to Driverack PA
Post by: Geoff Doane on March 31, 2011, 12:20:06 PM
If you set yourself up so that the mixer is at clip just before the amps you KNOW when your out of gas.. so to speak.

I think you want that the other way around, particularly if there is something (the DRPA) in between the mixer and the power amps that will provide limiting.

The fact that the OP is NOT losing drivers, but previous operators did, suggests to me that he is at least listening to what is going on with the system, and not just pushing it until something breaks. 

In some respects, the amplifier clip limiters will provide the "fast" limiting desired, although only at a fixed level.  The DRPA limiters can take care of the "RMS" limiting to keep drivers from being cooked (as opposed to being blown apart from over excursion).

GTD
Title: Re: Alternative to Driverack PA
Post by: Nils Erickson on April 08, 2011, 04:08:18 AM
Thanks for all the reply's!

I checked out the Jupiter series, and I like how it is all accessed via computer.. keeps those who shouldn't be there out of the processing! However it still won't happen due to the cost.. will definitely check out the Behringer unit, and maybe keep an eye out for a used 260.

Thanks for the suggestions of gain structure, that will be a very handy way of monitoring everything without walking back and forth to the amplifiers.

For the meantime, I have inserted a Behringer MDX1600 stereo comp between the DRPA and the Mid amplfiers, as those are the ones clipping the most, and that has seemed to help a ton. Every once in a while a transient will clip, but for the most part lights are in the green.

What is interesting however is that one of the Mid amps clips 6 or so dB sooner, and only clips on the right channel (it is run Bridged mono). I assume this is due to heat, but that's for a future discussion.... Thanks again!

On some amps (QSC PLX for example), you need to be certain that only one channel's input knob is turned up when you are in bridge mode.  Could this be the source of the problem on your mid amp?

Nils
Title: Re: Alternative to Driverack PA
Post by: Tim McCulloch on April 08, 2011, 03:03:08 PM
What is interesting however is that one of the Mid amps clips 6 or so dB sooner, and only clips on the right channel (it is run Bridged mono). I assume this is due to heat, but that's for a future discussion.... Thanks again!

Uh.. using bridge mode makes your output gain 6db hotter.  Turn down the right channel completely (as per the manufacturer) and turn down the left input by 6dB.

This is pilot error, not an equipment problem.