Noob Question

[Afortier]

I have a 100 watt 2 channel yamaha amp.
(more specifically a yamaha b-2x)
i was wondering if i could run two floor standing speakers on the a channels and sub off one of the b channels
ie e
channel 1:
A speaker

BSub

Channel 2
A speaker

B-nothing

will this work?
is it a bad idea?
do i need a seperate amp for a sub?
thanks.

 

[Augjer]

What kind of sub? You probably don't want an output with "nothing" since this can be bad for the amp driving into no resistance...?

Also, what is the impedance of the speakers?

 

[Afortier]

I havent decided on the sub yet(still thinking this out)
8 ohms.

 

[kevzep]

What kind of sub? You probably don't want an output with "nothing" since this can be bad for the amp driving into no resistance...?

Also, what is the impedance of the speakers?

Just to clarify, driving a Solid State amplifier with no speaker connected will not cause any damage to the amplifier whatsoever.
Driving nothing means it would be driving infinite resistance not no resistance.

A single sub would be best driven off a separate amplifier with a sum of Left and Right.
A and B outputs are usually just alternate speaker connections from the same amplifier....

 

[bryblob]

If you haven't got the sub yet why not get a powered one and just run it off your pre outs?

 

[musichal]

Even if you buy a passive sub, the few I've seen had dual voice coils so that you still hooked up both channels of your amp. If by sub, you mean a raw driver that you order yourself, then a dual voice coil model would be the way to go if you MUST do this. However, passive subwoofers are not generally the way to go, and if you do go that route is best done only if the passive sub was built by the same company as your main speakers specifically for your model and come in a cabinet with crossover. Even then, they don't tend to satisfy most people. That has been my experience, YMMV.

If a subwoofer has its own amps, then that is a powered subwoofer and virtually all of them will have the option of connecting either by sub output or with speaker wire from both channels of your receiver - if you connect with speaker wire your amplifier is not powering the sub - the subwoofer simply uses a circuit to get the bass signal and drives the woofer with its own built-in amp. That is handy for receivers that have no sub out jack, and both channels are connected

 

[Hajidub]

If the sub is powered and doesn't have outputs to your main speakers, just daisy chain the the sub off of your mains.

 

[Lazarus Short]

What kind of speakers are you using? Are you sure they need the assistance of a sub?