ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1]   Go Down

Author Topic: Rack DSP or Crown amp DSP?  (Read 2536 times)

Mario Roman

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 52
Rack DSP or Crown amp DSP?
« on: February 17, 2011, 01:29:06 pm »

Good day All,

For those who haven't been following my recent posts. I've finally received and put together my new system consisting of 2 Danley SM96 tops & 2 TH118 subs, 1 ITech8000 for subs, and 1 DSI4000 for mains for my "weekend warrior" classic rock gig. Based on the reviews from many on this forum I purchased a DCX2496 processor (over the driverack) a couple years ago. It's performed flawlessly and sounded good with my previous rig. (U15PB's over LS800PB's).

Currenty I've setup the new rig using the DCX unit but I'm wondering if I would notice a sound quality difference using the DSP in the Crown amps instead.   Will it be a "six of one, half dozen the other" kind of thing or "definately use the Crown DSP, it blows the DCX processing away".    Opinions please???    I'm new to using a passive system and while setting up crossovers etc is easy enough, I'm not quite sure where I sould be setting the protection and gain structure in the Crown units. In particular the ITech running the subs. When A/B ing the new subs to the old LS800p's, they blew away the Danley in level until I turned up the "band pass gain" setting in the Crown to+15db. Then the output on the db meter (and my ears) was equal. I went through the sensativity settings a little but that didn't seem to have much effect. Since I work for an A/V integrator I've dabbled with System Architect before but have never used it to actually set up a customer system. If anyone has used these amps and can shed a little light on what I should be using for limiter/gain/sensativity settings it would be greatly appreciated. I've done a lot of web research and have some good ideas but knowing what people are using "real world" is always helpful. Thanks again.

Mario
« Last Edit: February 18, 2011, 01:03:58 pm by Mario Roman »
Logged

alfredo cannon

  • Newbie
  • *
  • Offline Offline
  • Posts: 44
Re: Rack DSP or Crown amp DSP?
« Reply #1 on: February 17, 2011, 04:29:35 pm »

I have a similar rig to yours. A pair of TH-115 (4 ohm boxes) and a pair of EV Qrx 212/75 (bi-amped). I run my subs aux fed. You should run aux fed subs. It's so much better that way. I have a driverack PA for back up but my main dsp is a Ashly Protea 3.6
  Aux fed, dude. you're missin out!
Logged

Mario Roman

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 52
Re: Rack DSP or Crown amp DSP?
« Reply #2 on: February 17, 2011, 06:04:11 pm »

I've always run my rig with subs on aux. One of the reasons I chose the DCX2496 over the Driverack was that it had 3 inputs and 6 out. Thus my input 1 & 2 are left and right out of my 01v96 and input 3 is the aux out for my subs.

Mario
Logged

George Dougherty

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 724
Re: Rack DSP or Crown amp DSP?
« Reply #3 on: February 17, 2011, 11:37:40 pm »

Used to use a DCX2496.  DSP was okay, outputs seemed noisy.  If you've got the amp DSP to use at the very least it lightens up the rack a little.  I'd expect the built-in DSP is also quieter.
Logged

Tim McCulloch

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 19981
  • Wichita, Kansas USA
Re: Rack DSP or Crown amp DSP?
« Reply #4 on: February 18, 2011, 02:46:58 pm »

Good day All,

For those who haven't been following my recent posts. I've finally received and put together my new system consisting of 2 Danley SM96 tops & 2 TH118 subs, 1 ITech8000 for subs, and 1 DSI4000 for mains for my "weekend warrior" classic rock gig. Based on the reviews from many on this forum I purchased a DCX2496 processor (over the driverack) a couple years ago. It's performed flawlessly and sounded good with my previous rig. (U15PB's over LS800PB's).

Currenty I've setup the new rig using the DCX unit but I'm wondering if I would notice a sound quality difference using the DSP in the Crown amps instead.   Will it be a "six of one, half dozen the other" kind of thing or "definately use the Crown DSP, it blows the DCX processing away".    Opinions please???    I'm new to using a passive system and while setting up crossovers etc is easy enough, I'm not quite sure where I sould be setting the protection and gain structure in the Crown units. In particular the ITech running the subs. When A/B ing the new subs to the old LS800p's, they blew away the Danley in level until I turned up the "band pass gain" setting in the Crown to+15db. Then the output on the db meter (and my ears) was equal. I went through the sensativity settings a little but that didn't seem to have much effect. Since I work for an A/V integrator I've dabbled with System Architect before but have never used it to actually set up a customer system. If anyone has used these amps and can shed a little light on what I should be using for limiter/gain/sensativity settings it would be greatly appreciated. I've done a lot of web research and have some good ideas but knowing what people are using "real world" is always helpful. Thanks again.

Mario
Hi Mario-

Actually, your issue is that you need three filters across 2 amps.  You can't do that with the I-Tech.  The loop through signal output is unprocessed.  You need a high pass filter on the subs, a low pass filter on the subs, and a high pass filter for your SM96s.  Of those, I'd do the sub woofer HPF in the I-Tech, along with whatever input or output EQ you decide it needs.  For the sub LPF and top box HPF, I'd use the DCX... IOW, use the DCX to cross over between subs and tops, and use the in-amp processing to HPF and limit the sub woofers.

Haystacking the sub output is not unheard of.  In the VerTec 4889/4880 crossover, the sub woofer pass band output is set for +10dB.

Have fun, good luck.

Tim Mc
Logged
"Practicing an art, no matter how well or badly, is a way to make your soul grow, for heaven's sake. Sing in the shower. Dance to the radio. Tell stories. Write a poem to a friend, even a lousy poem. Do it as well as you possible can. You will get an enormous reward. You will have created something."  - Kurt Vonnegut

Mario Roman

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 52
Re: Rack DSP or Crown amp DSP?
« Reply #5 on: February 18, 2011, 03:48:20 pm »

Thanks for the reply Tim. Actually what I had in mind was to use the DSI4000 processing for the SM96's. 1 per side 1200w rms ea. and use the ITech processing for the aux fed subs. 1 per side 4000w rms ea. My set up is this way currently except all the processing is being done in the DCX before it goes to the amps. I'm just curious if there is any noticible sonic quality benefit to repatching everything around the DCX and doing everything in the amps. Logic would suggest that the expensive Crown amps processing "must" be better than the Behringer, but we all know that sometimes that's not always the case. :o

After reading a lot of Bennett's articles as well as others on this forum, I've learned a great deal about what destroys drivers. Thus I'm very glad the ITech has average power limiting. I which all amps did instead of just clip limiters. Currently I have the APL in the ITech set to -3db of the rms power of the TH118's driver. If I calculated correctly this should be 900w. I set the attack and release time to 10 seconds. What do you think? I'm not sure about the clip limiter. How do I determine at what level I will start clipping the input of the amp? This the area that I'm not exactly sure about. Will changing the input sensativity make a difference in when the amp input will clip? Any enlightenment is always appreciated. Thanks.

Mario
Logged

Tim McCulloch

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 19981
  • Wichita, Kansas USA
Re: Rack DSP or Crown amp DSP?
« Reply #6 on: February 18, 2011, 06:30:49 pm »

Thanks for the reply Tim. Actually what I had in mind was to use the DSI4000 processing for the SM96's. 1 per side 1200w rms ea. and use the ITech processing for the aux fed subs. 1 per side 4000w rms ea. My set up is this way currently except all the processing is being done in the DCX before it goes to the amps. I'm just curious if there is any noticible sonic quality benefit to repatching everything around the DCX and doing everything in the amps. Logic would suggest that the expensive Crown amps processing "must" be better than the Behringer, but we all know that sometimes that's not always the case. :o

My reasoning for using the DCX as the crossover between subs/tops is that you can be certain the filters are computed the same way.  You have no certainty between manufacturers.  There's a good post about system DSP filters (with pictures!) in the FUDforums Classic LAB.

Quote
After reading a lot of Bennett's articles as well as others on this forum, I've learned a great deal about what destroys drivers. Thus I'm very glad the ITech has average power limiting. I which all amps did instead of just clip limiters. Currently I have the APL in the ITech set to -3db of the rms power of the TH118's driver. If I calculated correctly this should be 900w. I set the attack and release time to 10 seconds. What do you think? I'm not sure about the clip limiter. How do I determine at what level I will start clipping the input of the amp? This the area that I'm not exactly sure about. Will changing the input sensativity make a difference in when the amp input will clip? Any enlightenment is always appreciated. Thanks.

Mario

The 'clip eliminator' only affects OUTPUT clipping.  It is still possible to clip the inputs.  The "Maximum Analog Input Level" adjustment on the I-Tech determines the clip point, either analog or digital (at the A/D converter).  You can also adjust the input sensitivity of the amp, the range of which is governed by the max analog input setting.

If you're doing live rock, contemporary country, praise & worship - music with dynamics - you'll never see the RMS limiter come on at 900w.  Contact Ivan for suggestions about peak voltage limiting and possible RMS limiter settings.

Have fun, good luck.

Tim Mc
Logged
"Practicing an art, no matter how well or badly, is a way to make your soul grow, for heaven's sake. Sing in the shower. Dance to the radio. Tell stories. Write a poem to a friend, even a lousy poem. Do it as well as you possible can. You will get an enormous reward. You will have created something."  - Kurt Vonnegut
Pages: [1]   Go Up
 


Page created in 0.038 seconds with 23 queries.