Hello,

I hava a question concerning using a Onkyo receiver ( model TX-SR575) to power a speaker selector/volume control. The speaker selector can control up to 6 pairs of speakers, any conbination of speakers or just one pair. Each pair has it's own volume control. It also manages impedance and avoids the whole series vs parallel issue.

I don't know which of the speakers outputs to use: "A" which includes Front L/R, Center, Surround L/R, and Back L/R. Or I could use the "B" output which I believe is the Back L/R only. ( when you select both "A" and "B" speakers, the system becomes a 5.1 and the Back L/R power is sent to the "B" speakers)

The six pairs of speakers that the selector will control are all identical. 115W, 8ohm outdoor patio speakers. What I am not sure of is how the power is managed if only the "B" speakers are selected. The Specs of the receiver are listed below. It seems each channel has 160 watts ( 80w per L/R speaker) But if only the "B" is selected, does it get more than 160 Watts?

I am assuming that the watts are divided equally among all speakers connected to the speaker selector so that if I have all six pairs selected "on" and at full volume, then each speaker is getting only 13 watts. (160 watts total divided by 12 speakers = 13watts.)

If "B" speakers only get 160watts total, then could I use "a" instead? The speaker selector has only one imput: L and R so that if I tried to use "a" speakers then I would have to bunch up all the "rights" and all the "lefts" ( Front L/R, Center, Surround L/R, and Back L/R ( I would leave center out or attach it to either the left or right). Would I then get the benefit of each channels power 160, 160, 160, and 80 for a total of 560 watts? Or would this be considered bridging an amp and create all kind of power issues?

I'm not concerned at all about losing the surround effect. As long as I have stereo, that's fine.

any comments?








Amplifier Section

Power Output

Front L/R 80 W + 80 W (8 ohms, 20 Hz-20 kHz,
0.08%, 2 channels driven, FTC)
100 W + 100 W (6 ohms, 1 kHz, 0.1%,
2 channels driven, FTC)

Center 80 W (8 ohms, 20 Hz–20 kHz, 0.08%,
2 channels driven, FTC)
100 W (6 ohms, 1 kHz, 0.1%, 2 channels
driven, FTC)

Surround L/R 80 W + 80 W (8 ohms, 20 Hz–20 kHz,
0.08%, 2 channels driven, FTC)
100 W + 100 W (6 ohms, 1 kHz, 0.1%,
2 channels driven, FTC)

Surround Back L/R 80 W + 80 W (8 ohms, 20 Hz–20 kHz,
0.08%, 2 channels driven, FTC)
100 W + 100 W (6 ohms, 1 kHz, 0.1%,
2 channels driven, FTC)

Dynamic Power 180 W (3 ohms, 1 ch)
160 W (4 ohms, 1 ch)
100 W (8 ohms, 1 ch)

THD (Total Harmonic Distortion) 0.08% (Rated power)

Damping Factor 60 (Front, 1 kHz, 8 ohms)

Input Sensitivity and Impedance 200 mV/47 k-ohms (Line)

Output Level and Impedance 200 mV/470 ohms (Rec out)

Phono Overload -

Frequency Response 5 Hz–100 kHz/+1 dB, -3 dB (Direct mode)

Tone Control ±10 dB, 50 Hz (Bass)
±10 dB, 20 kHz (Treble)

Signal-to-Noise Ratio 100 dB (Line, IHF-A)

Speaker Impedance 6 ohms–16 ohms


Video Section

Input Sensitivity/Output Level and Impedance

Video 1 Vp-p/75 ohms (Component and S-Video Y)
0.7 Vp-p/75 ohms (Component PB/CB, PR/CR)
0.28 Vp-p/75 ohms (S-Video C)
1 Vp-p/75 ohms (Composite)

Component Video Frequency Response 5 Hz–50 MHz


Tuner Section

Tuning Frequency Range

FM 87.5 MHz–107.9 MHz

AM 530 kHz–1,710 kHz

FM/AM Preset Memory 40 stations


General

Power Supply AC 120 V, 60 Hz

Power Consumption 4.9 A

Dimensions (W x H x D) 17 1/8" x 5 7/8" x 14 13/16"
(435 x 150 x 377 mm)

Weight 20.9 lbs. (9.5 kg)

I would say re-read the manual. The power ratings are not always accurrate. I'm sure the manual has several diagrams on speaker connections.
Why do you want to operate in 'stereo', when you have a '7.1 system' ?
I run all my speakers on "A", except my passive sub is on 'B'.
Just my comments................

John

Thanks John,

I plan to use Stereo instead of 7.1 simply because I don't believe I can use the 7.1 feature with the speaker selector. How could you hook it up? The speaker selector only wants/needs right and left negative and positive..that's it. That's what the "B" speakers output provides. What would I do with front, surround, center, back speakers outputs? Twist all the Rights together and all the lefts together and throw the center to either one? I think what I need is an old fashion stereo receiver with a high current amp. You know, a simple 2 channel 120watt/channel receiver. That would power my speaker selector and drive all twelve speakers. The "home theater" receiver has too many features that I just don't need. These 12 speakers are outside, around a pool and pool house. I don't need surround sound, I just need stereo.

Thanks for the thoughts

I read a thread in 2 channel audio that recommended a Panasonic SA-XR55 because it could be Bi-amped...combining the Front right with the Rear Surround Right amps to drive the right speaker and the Front Left with the Rear Surround left to drive the left spreaker...my Onkyo manual does not mention nor diagram any biamping capabilities...I wonder if I could do this?

Yor,
You really need a 'stereo amplifier'. They are usually big amps with lots of watts to drive multiple speakers. I looked for articles on 'stereo amps' but I couldn't find any!
Normally the speakers are wired in parallel. I don't know how the speaker selector/volume control would work. I assume you got directions when you bought it.
Here is a link to several 'stereo amps' with the tech.specs. included. Maybe if you post in the other section ( 2 Channel Audio) , you would get more help.
http://www.amazon.com/Onkyo-Integrated-Digital-Stereo-Amplifier/dp/B000J0ORMS#moreAboutThisProduct
Good luck....
John

Thanks John

Yor,
Your receiver s/b able to work to drive a few speakers. I looked at this 6-speaker selector, I assume you have something similar. I guess you could use two outputs(fronts) from your receiver to input your speaker/selector. I don't know how many speakers in parallel you could drive though; receiver specs. says 6ohms. let us know what happens.
http://www.crutchfield.com/App/Product/Item/Main.aspx?g=15240&i=190SS6&tp=2997
Another article...........
http://www.informit.com/articles/article.aspx?p=354355&seqNum=5
John