Axiom Home Page Forums General Discussion Technical Questions speaker selector

I'm planning to use the zone 2 output on my Onkyo 805 to power speakers in different rooms of my house. In order to do this I need a speaker selector like the following.

http://www.amazon.com/PSS6-Six-Zone-Ster...56823753&sr=1-7

http://outlet.crutchfield.com/p_190SS4/Niles-SS-4.html?cc=07&search=speaker+selector&ssi=0

http://www.amazon.com/s/ref=nb_ss?url=se...elector&x=0&y=0

http://www.crutchfield.com/app/product/s...elector&x=0&y=0

Are all of these selectors just setup so that the speakers are wired in parallel? So if you have two 8 ohm speakers then you have a 4 ohm load on your amp. If you have three of them then you dip below 4 ohms and I may have problems, right? Are there any speaker selectors that have a way around this low impedance problem? What is the most that I would want to pay for one of these since they can range from $30 to $400 or $500? All I want is a selector setup for four rooms and I don't need independent volume control for each room. Obviously I want my Onkyo 805 to be able to drive this at reasonable volumes as well.

- Nick

Hi Nick,

You want to use a "constant-impedance" selector that will prevent the impedance of multiple pairs from falling below 4 ohms.

Sorry my ultra-sensitive touch pad posted this before I finished. . .

Niles has an inexpensive one--the SS4 should work, so long as your Onkyo doesn't have an ultra-sensitive protection circuit that shuts things down when it senses a 4-ohm load. Older Onkyos use to do that but I think the newer ones are better.

Here's a link to another switcher that keeps impedance no lower than 4 ohms:

http://www.escience.ca/hobby/RENDER/0001/21/3030/13076.html

Regards,

Hi,

To answer your question, the lower-priced ones have internal resistors which waste power but keep the impedance from going below 4 ohms. Those should be adequate if your speakers in the other rooms are not intended for super fidelity.

Alan

Alan,

The internal resistors would waste the power if more than one pair of speakers is being used, or does this happen all of the time? If this happens only when more than one pair is being used at the same time then I don't really care, because I plan to rarely use it that way. I do have a good set of Aperion audio speakers that I will be mounting in one room that I would like to get a nice sound out of though.

- Nick

Hi Nick,

I think it would happen only when more than one pair of speakers on the switcher were engaged. It wouldn't be a big power loss. You could order one and try it out temporarily with a couple pairs of speakers to see if it works OK and doesn't cause your Onkyo to shut down.

My comment on the fidelity issue is based on the idea that the resistors may interact with the impedance of the speaker in an unpredictable way. This is speculation on my part based on comments from Axiom's chief engineer, Tom Cumberland, when I asked him about multiple speaker hook-ups and constant-impedance switching devices.


Alan

Hey Alan,

Can you recommend something that one could use for doing Blind A/B testing between speaker brands? I assume it would have to be a speaker slector with some type of dB level matching ability? Oh, and it would have to be cheap. WAF

Randy

Randy,

The tech guy at Axiom built one for me, so I'm not up on where you'd find a commercial unit. I'm sure they're available. On my switcher, the adjustment for different speaker sensitivities has a limited range, but enough for the differences in Axiom models and some other brands I have kicking around for comparison purposes. Mine will only accommodate two pairs of speakers-- "A" and "B."

Alan

So you've never been able to tell if C is better or not? Tss. Not professionnal!

And I'll bet that all this time, "C" WAS the kick-ass choice, and we've all suffered because of Alan's laziness / cheapness in not getting an A/B/C switcher.



Damn. I was gonna buy him a beer someday if we met.