Help with right amplifier for passive subs

R

Russdawg1

Full Audioholic
There's no EQ in the XLS amps either gen 1 or 2....
Oh geez sorry. I mean the iNuke.

The iNuke only has 5 bands and the high pass only goes as low as 20hz.

That’s why you need the shelf for ULF subs.
 
lovinthehd

lovinthehd

Audioholic Jedi
The Behringer may be a bit noisy, so if no equipment separation from your room you may want to do a fan mod. Same could go for a variety of pro amps. QSC I believe has some amps that would work as well. Maybe a Speakerpower amp....but those are kinda pricey :)
 
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Danzilla31

Audioholic Spartan
The Behringer may be a bit noisy, so if no equipment separation from your room you may want to do a fan mod. Same could go for a variety of pro amps. QSC I believe has some amps that would work as well. Maybe a Speakerpower amp....but those are kinda pricey :)
Don't the crown amps have a filter that starts at 20 hz I've read somewhere that they do but I've also read that they also can play flat to 10hz and can bottom out a sub

Okay since its so much cheaper to buy a mini dsp I may just have to admit defeat here and settle for one

It's hard to swallow buying 2 new amps when I have 2 perfectly capable ones right there

I don't want noisy darn amps in the room

But how would you go about connecting the xlr and unbalanced to it from the prepro are there any problems with this?

There's plenty of tutorials on how to set them up and I'm sure RBH could walk me through it

That's my final questions guys thanks again!
 
lovinthehd

lovinthehd

Audioholic Jedi
Well, when I asked Crown this 5 years ago via email to Crown Support:
"I have two XLS1500s and the question of performance below 20Hz keeps coming up in forum discussions. I've read Crown advises that there is a rolloff below 20hz, I've seen both 12dB/octave and 24dB/octave mentioned and some who say its relatively flat. What are the actual specs in this regard?"

I got this in answer:
"It’s a 12dB per/oct roll off. It’s not fully flat to 20Hz, roll off will start a little bit above 20Hz.
The crossover points you can select are Linkwitz-Riley 24dB per/oct roll offs but the roll off at 20Hz is 12dB.
So the amp technically has both and may have mixed to two up."

I've seen others claiming measurments relatively flat to 10hz. You can check measurements at ASR, don't remember the guys claiming 10 to actually publish the measurements....

Now, a bit later in the email exchange I asked Crown about amps more suited to subs for lower extension and the same guy said:

"An amp without any form of DSP in it, the XLi and CTs. Still with both of these amps at some point below 20Hz you will trigger the DC/LF circuit. That is typically below 10Hz for that to be triggered."
 
lovinthehd

lovinthehd

Audioholic Jedi
Don't the crown amps have a filter that starts at 20 hz I've read somewhere that they do but I've also read that they also can play flat to 10hz and can bottom out a sub

Okay since its so much cheaper to buy a mini dsp I may just have to admit defeat here and settle for one

It's hard to swallow buying 2 new amps when I have 2 perfectly capable ones right there

I don't want noisy darn amps in the room

But how would you go about connecting the xlr and unbalanced to it from the prepro are there any problems with this?

There's plenty of tutorials on how to set them up and I'm sure RBH could walk me through it

That's my final questions guys thanks again!
What prepro for the connection to which minidsp?
 
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Danzilla31

Audioholic Spartan
What prepro for the connection to which minidsp?
It would be the anthem avm 60 has 2 balanced and 2 unbalanced sub outputs

The mini dsp would be the 2×4 right? Like I said total noob to this stuff here haven't dived in yet

About to tho!
 
lovinthehd

lovinthehd

Audioholic Jedi
It would be the anthem avm 60 has 2 balanced and 2 unbalanced sub outputs

The mini dsp would be the 2×4 right? Like I said total noob to this stuff here haven't dived in yet

About to tho!
Minidsp 2x4 comes in a few flavors. The latest and best version, the 2x4HD, has rca inputs/outputs. For the slightly older balanced version I just made rca to balanced cables (but those were phoenix inputs on that 2x4, not xlr).

 
D

Danzilla31

Audioholic Spartan
Minidsp 2x4 comes in a few flavors. The latest and best version, the 2x4HD, has rca inputs/outputs. For the slightly older balanced version I just made rca to balanced cables (but those were phoenix inputs on that 2x4, not xlr).

Cool thanks!
 
Verdinut

Verdinut

Audioholic Spartan
Should you want amplifiers working down below 20 Hz, the QSC DCA 2422 will provide a frequency response down to 5 Hz @ -3 dB (at 10 dB below rated output). With that, you should be able to reach 16.35 Hz easily, the fundamental frequency of a 32 foot organ pipe, and enough to shake your whole house:


Edit: I would suggest a dedicated 15 amp preferably a 20 amp circuit for each one
 
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Danzilla31

Audioholic Spartan
Should you want amplifiers working down below 20 Hz, the QSC DCA 2422 will provide a frequency response down to 5 Hz @ -3 dB (at 10 dB below rated output). With that, you should be able to reach 16.35 Hz easily, the fundamental frequency of a 32 foot organ pipe, and enough to shake your whole house:


Edit: I would suggest a dedicated 15 amp preferably a 20 amp circuit for each one
Hmmmm that looks juicy do they come with the dsp I'll need? I have no issues with dedicated circuits

I have 4 in that room 20amp each
 
NINaudio

NINaudio

Audioholic Samurai
For what it's worth, with a mini dsp 2x4 HD and a crown xls 1502 I'm able to get in room FR that is flat to 16 HZ.
 
Verdinut

Verdinut

Audioholic Spartan
Hmmmm that looks juicy do they come with the dsp I'll need? I have no issues with dedicated circuits

I have 4 in that room 20amp each
Unfortunately, they don't come with a DSP. I guess you could use a minidsp with them, couldn't you? Those QSC amps are not cheap. They are built in US and are warranteed for a full 3 years and you cannot kill them.
 
Verdinut

Verdinut

Audioholic Spartan
Unfortunately, they don't come with a DSP. I guess you could use a minidsp with them, couldn't you? Those QSC amps are not cheap. They are built in US and are warranteed for a full 3 years and you cannot kill them.
QSC have a DSP which could be used with the DCA 2422s. I don't know what they would sell for, but they're designed to be connected at the back of the 2422s:

 
Verdinut

Verdinut

Audioholic Spartan
Hmmmm that looks juicy do they come with the dsp I'll need? I have no issues with dedicated circuits

I have 4 in that room 20amp each
It looks like the QSC DSP-3 might be discontinued. You could check with Socalcinetech for info. Maybe they have some DSP-3s left:

Here is the phone number to reach QSC's Marketing department. They should be pleased to help you with any query about a replacement DSP: 800-854-4079
 
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Danzilla31

Audioholic Spartan
For what it's worth, with a mini dsp 2x4 HD and a crown xls 1502 I'm able to get in room FR that is flat to 16 HZ.
Yeah I'm thinking probably I'm going to have to go the mini dsp route I just can't stomach buying 2 new amps when I have 2 perfectly good ones right there

On my pre amp how do I connect xlr outputs from the preamp into the mini dsp is there a converter cable I can use?
 
lovinthehd

lovinthehd

Audioholic Jedi
Yeah I'm thinking probably I'm going to have to go the mini dsp route I just can't stomach buying 2 new amps when I have 2 perfectly good ones right there

On my pre amp how do I connect xlr outputs from the preamp into the mini dsp is there a converter cable I can use?
Why would you want to use the xlrs when the rcas are on each unit?
 
Verdinut

Verdinut

Audioholic Spartan
Yeah I'm thinking probably I'm going to have to go the mini dsp route I just can't stomach buying 2 new amps when I have 2 perfectly good ones right there

On my pre amp how do I connect xlr outputs from the preamp into the mini dsp is there a converter cable I can use?
You can get those or any equivalent Monoprice cable:

 
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Danzilla31

Audioholic Spartan
Why would you want to use the xlrs when the rcas are on each unit?
Well I'm ending up with 4 subs right?

I have 4 outputs from the anthem 2 unbalanced rca and 2 xlr

So I was planning on using the 2 xlr for the back since the subs in the front already are wired for rca and then the 2 rca outputs for the front I don't want to run xlr runs up to the front through the attic

Am I making any sense I don't know if I'm supposed to use a splitter on the rca outputs I think the anthem Manuel doesn't recommend it

I hope I'm making sense here

Don't I have to connect each sub output from the preamp to the mini dsp?
 

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