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Impotence Question

Now that I have your attention...my question is about impedance matching in speaker selectors. I have a Bryston 3-way speaker switch box, which does not have impedance matching/balancing. As far as I understand it is a simple three-way switch box with minimal signal path to travel. It has three on/off buttons which operate independently from each other. So I was curious what exactly happens when I switch my 100 watt amp to drive two pairs of 8-ohm monitors simultaneously (yes, besides the fact that both sets of speakers are playing)? Are there sacrifices in performance, and are those sacrifices linear or do they show up in different ways for each pair of speakers? It does not occur to me to drop the volume significantly in one pair of speakers when engaging the second pair which are downstairs, though I imagine this must happen as it's splitting the output of one amp between two pairs of speakers. So what is going on, and how does it differ from a selector which compensates for impedance? I think Niles actually terms their system "Impedance Protection".

Marco
jax2
tripper
223 posts
 
Marco, You are indeed doubling the load to 4 ohms, nominally. Most [tube] amps [if that's what you are running] are not well-equipped to drive such loads, 4- ohm taps notwithstanding. Even many ss amps don't like low impedance loads. Of course, the proof is in the pudding, or listening, in this case.
Niles probably runs an interstage xfrmr for such purposes. Not all xfrmrs are bad, but the Niles' first priority may not be sound quality. Better to procure an amp for the second pair, although gain-matching issues come into play unless amps and spkrs are respectively identical. The Hafler "quad" ckt may be an option. Oops, guess not if one pair is downstairs. I just imagined the horror of 50 foot cables, too long for any sane app. Sorry if I raised more ?S than answers, but that may go to the root of your problem. Best is two spkrs, one amp, imo. Perhaps a condom next time?
eldartford
4,262 posts
 
There will be only slight reduction of volume when the second speakers are connected. The amp will put out a certain voltage (corresponding to volume level) but with two speakers being driven the amp will have to pump out twice as much current to maintain the voltage.

Give it a try and see how it works before spending much money.
quadophile's avatar
quadophile
418 posts
 
Marco,

You certainly got my attention with your catchy title, but, I am sorry I cannot answer your question, it's just that I thought someone wants all of us to know that listening to too much music may lead to the person becoming impotant, thank God it is not the case :)
Post removed 
jax2 OP
3,031 posts
 
Viridian - you slay me! Don't mind if i do:

Tripper - calm down dude...you haven't called 911 yet have you? No tubes in this system...this is really my WAF system and I'd certainly admit there are a few compromises. Nevertheless, it sounds purty damn good. 100 watt integrated (Portal Panache). 25 foot run of 14ga downstairs if you must know. Tara cables to the mains..bi-wired. But I swear, I cannot hear any difference in volume engaging the second pair of speakers. Weird...that's what I would've thought too. What gives there? Upstairs Silverline SR17s, downstairs Soliloquy SAT5's. Respectively 89db and 87db sensitivities at 8ohms.

Any further insight?

Really, no need to panic. Nothing happening here folks...go on home now....nuthin' ta'see here now, break it up now....go'on, git!

Marco
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