Daisy Chaining 4 QW2F Speakers Bi-Amp

This forum is for talking about all kinds of Peavey power amplifiers.
A1marine
Member
Posts: 60
Joined: Mon Mar 14, 2011 12:07 pm

Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by A1marine » Mon Apr 23, 2012 6:12 pm

I think I can do this without any problem but I thought I would ask. I would like to Bi-Amp 4 QW2F's (2 to a side daisy chained). I have a VSX-26 to (2) - CPX2600's Bridged for the mids and an IPR 1600 for the Highs. I think if I read it right the CPX2600 bridged puts out 2200 into 4ohms which would work with the combined 2400 program rated mids. The IPR 1600 puts out 530 a side @ 4ohms if I read that right which would work fine with the 800 max combined rating. Before I hook this up and try it please let me know if i'm on the right track.

P.S I have 4 QW218's with 4 GPS 3500's Bridged for the subs.

User avatar
SemperFiSound
Member
Posts: 9820
Joined: Sun Oct 12, 2008 8:39 pm
Location: NW Florida - Pensacola area

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by SemperFiSound » Mon Apr 23, 2012 6:50 pm

A1marine wrote:I would like to Bi-Amp 4 QW2F's (2 to a side daisy chained).
...roger.
A1marine wrote:I have a VSX-26
...most excellent!
A1marine wrote: (2) - CPX2600's Bridged for the mids...the CPX2600 bridged puts out 2200 into 4ohms
...and you want to do two per CPX? Two QW-4 Low freq portions in parallel is a 2 Ohm load. Doubtful that the CPX is rated that low in Bridged mode.
A1marine wrote:IPR 1600 for the Highs.
highs are an 8 Ohm load per cabinet and so two is a 4 Ohm load. The 1600 will give you 530W each side at 4 Ohms for 265 per horn - just a bit above program, but probably sufficient.

You need to revisit your Low end on the QW-4.

Cheers,
Steve
SemperFi Sound; the website
SemperFi Sound On FaceBook
"The Art of War teaches us to rely, not upon the calculated likelihood of
the enemy's coming or not, but on our own readiness to receive him... no
matter what he does." Sun Tzu

mrmagoo
Member
Posts: 181
Joined: Tue Sep 20, 2011 9:26 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by mrmagoo » Mon Apr 23, 2012 8:46 pm

Two QW-4 Low freq portions in parallel is a 2 Ohm load.
They are QW2Fs not QW 4s.
2-SP2s, 2-SP218s, VSX 26, Kosmos, 902 mixer, PV-6
CS 1400, 4000, 4080, M-2600
2-115 internationals
1-SP118
IPR 1600 DSP
PV-1200

Stryker57
Member
Posts: 951
Joined: Fri Aug 20, 2010 9:39 am
Location: Cincinnati,Ohio

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by Stryker57 » Mon Apr 23, 2012 10:35 pm

mrmagoo wrote:
Two QW-4 Low freq portions in parallel is a 2 Ohm load.
They are QW2Fs not QW 4s.

Bah ... details
:mrgreen:

1958sedwards
Member
Posts: 626
Joined: Mon Sep 15, 2008 5:20 am
Location: Sydney Australia

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by 1958sedwards » Tue Apr 24, 2012 3:17 am

Hi

The ideal Peavey amp setup for QW2 speakers is a CS4080 for the 15s and a CS2000 for the 44XT. This means that 2080 watts into 4 ohms and 760 watts into 4 ohms. Both of these amps have 40 times (32dB) of gain.

Your suggestion of Bridged CPX2600 is just fine (eventhough I don't usually recommend bridge mode) but I think the IPR1600 might be a little on the small side. Not that this is unworkable but just a little limiting as far as headroom is concerned. I would not recommend the IPR3000 as this will be quite a bit over the Peak rating of the compression driver.

The biggest concern, and something which you MUST take into consideration the significantly different gain structures of the two amplifiers!

Regards

Steve

User avatar
SemperFiSound
Member
Posts: 9820
Joined: Sun Oct 12, 2008 8:39 pm
Location: NW Florida - Pensacola area

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by SemperFiSound » Tue Apr 24, 2012 4:54 am

Stryker57 wrote:
mrmagoo wrote:
Two QW-4 Low freq portions in parallel is a 2 Ohm load.
They are QW2Fs not QW 4s.

Bah ... details
:mrgreen:
Damn details. okay..QW-2s.

See the "other" Steve's post then....ignore mine - sort of.
Cheers,
Steve
SemperFi Sound; the website
SemperFi Sound On FaceBook
"The Art of War teaches us to rely, not upon the calculated likelihood of
the enemy's coming or not, but on our own readiness to receive him... no
matter what he does." Sun Tzu

A1marine
Member
Posts: 60
Joined: Mon Mar 14, 2011 12:07 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by A1marine » Tue Apr 24, 2012 8:56 am

Thanks Guys! I'm just trying to use what I have to get by till those elusive other IPR's show their face. I read somewhere that I should run the gain knobs at around 2 o'clock on the IPR 1600 to match the 40x gain of my other amps so the limiters in the VSX-26 work correctly. But because you think the IPR 1600 is a bit under powered should I turn it up a little? I'm learning alot everyday from these forums, and I'm sure you have saved me hundreds of dollars in trial and error. Now that I have the green light i'm going to try it out on our next big show. Thanks!

Marty McCann
Member
Posts: 4478
Joined: Mon Oct 27, 2008 3:50 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by Marty McCann » Tue Apr 24, 2012 10:18 am

>>>
But because you think the IPR 1600 is a bit under powered should I turn it up a little?
<<<

No, NO, that shows you do not understand gain structure. If you turn it up you do NOT get more power than the amp is capable of, you simply unbalance the system where the highs would be too loud.
Attachments
HOW_MUCH_POWER.pdf
(228.56 KiB) Downloaded 442 times
Voltage Gain.1.pdf
(87.06 KiB) Downloaded 323 times

A1marine
Member
Posts: 60
Joined: Mon Mar 14, 2011 12:07 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by A1marine » Tue Apr 24, 2012 1:13 pm

Thanks Marty. Your right, I have alot to learn on voltage gain. I'm pretty sure after looking at all the math that I am not savvy enough in the wath department to get this right. But after reading your reply and some other posts I feel I could have a couple of other problems maybe? By Bridging the CPX2600's and the GPS3500's I'm turning them into 80x voltage gain amps as well??? and the IPR1600 is 60X So to make my VSX-26 and my speakers happy I should turn the gain knobs on the CPX2600's to 12:00 and the IPR1600 to 2:00

If I have this screwed up, pretty please, just tell me where to set the knobs, my head is starting to hurt.
Thank You!!!

P.S I'm using the QW2 QW218 preset in the VSX-26

tmbrandis
Member
Posts: 394
Joined: Sat Jan 09, 2010 8:09 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by tmbrandis » Tue Apr 24, 2012 1:50 pm

No. The only amp that will need to have it's knobs turned down is the IPR1600.

I have all x40 gain amps (PV's) and all of them run wide open. This holds true for the 4 GPS3500's I'm running in bridged mode, which would make them x80, they're still run wide open.

It's the DSP that cares about the gain(s). If they're not all matched the crossover points get out of whack and the limiter settings will not be right.
Tom in Baltimore

8 VR218's, 6 QW218's, 6 QW2F's, 2 QW3's, 4 QW1's, 4 QW215's, 18 VR112's, 16 QWmonitors.
14 GPS3500's, 6 CS4080Hz's, 12 CS4000's, 6 CS3000's, 4 GPS2600's, 4 GPS1500's.

A1marine
Member
Posts: 60
Joined: Mon Mar 14, 2011 12:07 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by A1marine » Tue Apr 24, 2012 2:01 pm

Cool! As far as the limiters go, I thought they were set when I down loaded the preset. I just read that is'nt the case. Can some one that has the QW2QW218 set up tell me what to set the limiters at on my VSX-26 with the voltage gain setup I have please? Thanks again!!!

tmbrandis
Member
Posts: 394
Joined: Sat Jan 09, 2010 8:09 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by tmbrandis » Tue Apr 24, 2012 2:07 pm

We'll certainly help you, but please do a little leg work for us so you can learn at the same time.

Here is the info we'll need:

The continuous wattage rating of each individual speaker from the spec sheet, the minimum ohms of each individual speaker from the spec sheet (not the nominal). If for some reason the minimum ohm is greater than the nominal ohm spec, give us the lower of the two.

I will make the assumption that you'll be running two QW2's per side and 2 QW218's per side (each QW218 running off it's own bridged amp)
Tom in Baltimore

8 VR218's, 6 QW218's, 6 QW2F's, 2 QW3's, 4 QW1's, 4 QW215's, 18 VR112's, 16 QWmonitors.
14 GPS3500's, 6 CS4080Hz's, 12 CS4000's, 6 CS3000's, 4 GPS2600's, 4 GPS1500's.

A1marine
Member
Posts: 60
Joined: Mon Mar 14, 2011 12:07 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by A1marine » Tue Apr 24, 2012 3:14 pm

Thanks! Your the best!!

Yes! 2 QW2F's per side Daisey Chained from 2 bridged CPX 2600's on top of 2 QW218's per side each fed by Bridged GPS3500's

QW2F Spec's Low Frequency 600W Continuous
High Frequency 100W Continuous
Minimum ohm Low Frequency 6.5
High frequency 7.1

QW218 Spec's 1600W Both Woofers Driven
7.3ohm's each woofer

A1marine
Member
Posts: 60
Joined: Mon Mar 14, 2011 12:07 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by A1marine » Tue Apr 24, 2012 3:17 pm

Woops I forgot the high's are being run by an IPR1600 Stereo

tmbrandis
Member
Posts: 394
Joined: Sat Jan 09, 2010 8:09 pm

Re: Daisy Chaining 4 QW2F Speakers Bi-Amp

Post by tmbrandis » Wed Apr 25, 2012 1:25 pm

QW2 highs, two per side daisy chained from a IPR1600 in stereo, your limiter setting would be: -1.5 (you'll have to adjust the IPR1600 to make it think its at 40x gain)

QW2 lows, two per side daisy chained from a bridged CPX2600, your limiter setting would be: 0 (not recommended as your load would then be at 3.25, which is lower than the 4 ohm rating the amp can handle in bridged mode) It'll probably be safe, but, I'd get a bigger amp so you can run in stereo mode and still have enough power. I'm not familiar with the Crest CPX series amps, so, i don't know how robust they are as compared to the GPS series. Marty may chime in on this. (1) CS4080 would handle all the 15's.

QW218 subs, one per bridged GPS 3500 your limiter setting would be: 2

NOTE: all limiter setting are rounded to the nearest .5 increment available in the VSX26 settings.
Tom in Baltimore

8 VR218's, 6 QW218's, 6 QW2F's, 2 QW3's, 4 QW1's, 4 QW215's, 18 VR112's, 16 QWmonitors.
14 GPS3500's, 6 CS4080Hz's, 12 CS4000's, 6 CS3000's, 4 GPS2600's, 4 GPS1500's.

Post Reply