Amp + Amp + one set of main speakers

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bmr63

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#36199 21-Jun-2009 23:16

Hi There,

This is my first post and I'm not terribly techical!

Yesterday I bought a Yamaha RX-V1900 Home theature Amp.
Have been trawling through the manual and there's a bit that worries me. Under multi zone configuration (which I won't use yet) theres a warning that says:

"Connection to a Passive Loudspeaker Selector Box or multiple speakers per channel could create an abnormally low impedance load resulting in amplifier damage."

For years now I have run one set of main speakers through my previous Home Theature Amp and a seperate 2 channel amp for music, via a QED switching box. Do you think this will be a problem? I wonder if the issue is more about folk selecting from multiple sets of speakers via a switching box, which is clearly not what I'm doing.

I'd appreciate your views on this.

Cheers

Batman

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#227238 22-Jun-2009 06:27

you run 1 speaker per speaker out. if you want to connect an amp use the preamp out. i dont recommend connecting everything via speaker out.

Batman

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#227239 22-Jun-2009 06:27

ps - that's an awesome receiver - how much did you get it for?

SepticSceptic

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#227401 22-Jun-2009 15:47

"Connection to a Passive Loudspeaker Selector Box or multiple speakers per channel could create an abnormally low impedance load resulting in amplifier damage."

I think they mean not to run a speaker switch box directly from tyhe speaker outputs, especially as some switch systems doa "make before break" meaning they make the connection to the next set of speakers before breaking the connection to the previous set, therefore creating a very low impeadance path when both pairs of speakers are bridged in parallel mode. You could end up with an impeadence of less than 2 ohms, which most amps will barf at. Shutdown / release smoke / etc

The separate 2 channel amp description that you mention won't have this issue., as everything is at a much higher impeadance.

bmr63

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#227506 22-Jun-2009 20:19

Thanks for that. Yes, I've not had that much time to have a play with it .....so many configuration options, so little time.

Just experiementing with the option of using it for 2 channel use (if anything...my CD player is now the system weakness...it never ends ).

Got the RX-v1900 for ~$2300 - on sale at Harvey Norman.

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#227513 22-Jun-2009 20:40

no it never ends! really, why dont you use the preamp outs for the other amp? the other option is to use zone 2 or B. mmmm rx-v1900 ... but it's way too costly!

if you want a new cd player get one with a hard disk!

Dingbatt

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#227514 22-Jun-2009 20:41

The V1900 is a 7.1 receiver with second zone capability. If your current home theatre set up is 5.1 (as most are) then you can just use channels 6 and 7 to power your two other speakers in a 'second room' configuration, even if they are in the same room.

That way there is no separate speaker switchbox and no chance of a low impedance/high current smoking amp moment.

Off the top of my head I can't remember, but does that model Yammy have A and B speaker connections as well?

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bmr63

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#227547 22-Jun-2009 21:58

Dingbatt: The V1900 is a 7.1 receiver with second zone capability. If your current home theatre set up is 5.1 (as most are) then you can just use channels 6 and 7 to power your two other speakers in a 'second room' configuration, even if they are in the same room.

That way there is no separate speaker switchbox and no chance of a low impedance/high current smoking amp moment.

Off the top of my head I can't remember, but does that model Yammy have A and B speaker connections as well?

There's up to three zones and I haven't completely got my head around that yet. Certainly understand what you are saying about multiple sets of speakers, but what I was asking about was effectively sharing one set of main speakers betrween two AMPs

cheers

bmr63

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#227550 22-Jun-2009 22:08

joker97: no it never ends! really, why dont you use the preamp outs for the other amp? the other option is to use zone 2 or B. mmmm rx-v1900 ... but it's way too costly!

if you want a new cd player get one with a hard disk!

Yep...considered the pre-outs idea, with the added advantage that both the Amp's could heat the room too

Actually don't own a flat screen yet - would have actually bought that first had it not been for my old (lower-mid-range) Sony HT Amp dying. CD player will have to wait. Do have Sony HDD/DVD recorder though. Oh but then there's MySky HDi...did we mention it NEVER ends

Cheers

Batman

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#227551 22-Jun-2009 22:09

bmr63: what I was asking about was effectively sharing one set of main speakers betrween two AMPs

cheers

ah i see now. as long as your switcher box separates the 2 circuits that ok i guess ... but if that fails you risk losing $2300 + / - speakers

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#227552 22-Jun-2009 22:11

also if the switcher box is not built well your $2300 receiver becomes effectively a $50 warehouse stereo as it passes the sound through it

bmr63

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#227553 22-Jun-2009 22:20

joker97: also if the switcher box is not built well your $2300 receiver becomes effectively a $50 warehouse stereo as it passes the sound through it

The switch box was UK built and seemed of fairly solid quality. I can't remember where I bought it (years ago), but it was at a Hifi place (ie NOT the warehouse

). I know what you mean though. I didn't appreciate any real issues with performance using it.

For now, it's out of the circuit and I'm enjoying the Yam in 2 Ch 'direct' mode.

Nice.

Cheers Joker97

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Dingbatt

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#227649 23-Jun-2009 10:28

Sorry I misunderstood your OP but the V1900 is quite a capable music amp as well so why not connect your CD player to it and run it in Stereo or one of the pure direct modes if you just want to power your L/R speakers.

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bmr63

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#227661 23-Jun-2009 11:05

Dingbatt: Sorry I misunderstood your OP but the V1900 is quite a capable music amp as well so why not connect your CD player to it and run it in Stereo or one of the pure direct modes if you just want to power your L/R speakers.

Yep, thanks mate, pretty much coming to that conclusion too. Took the switch out of the circuit last night and connected up the CD. Used Pure Direct and listened to a few disks. Was really very good so that's probably the direction I'm going in.

Cheers