play A/B channel together

[Sylar]

would it cause any issues if I play both channel A and channel B together? Connecting fronts to channel A and surrounds to channel B instead of to surrounds channel

 

[markw]

would it cause any issues if I play both channel A and channel B together? Connecting fronts to channel A and surrounds to channel B instead of to surrounds channel

I believe channel "B" is a two channel (stereo) channel. They won't be surrounds any more.

 

[slipperybidness]

would it cause any issues if I play both channel A and channel B together? Connecting fronts to channel A and surrounds to channel B instead of to surrounds channel

You should be able to hook it up on A and B. But, yeah, the B speakers will just be the same signal as the A speakers i.e. you lose the surround channel signal.

 

[Sylar]

I believe channel "B" is a two channel (stereo) channel. They won't be surrounds any more.

I was playing in stereo mode.
I ask this because, the AVR switched off while playing after a while. I was playing at pretty loud volume with crossover set at 40Hz. Fronts being PSB T6 connected to channel A and B5 to channel B. This is the first time it has switched off like this (havent played it like this much). There is ample ventilation from all sides. I was a surprised when this happened. Model is 7005 marantz AVR.
Wondering why the amp switched off

 

[slipperybidness]

I was playing in stereo mode.
I ask this because, the AVR switched off while playing after a while. I was playing at pretty loud volume with crossover set at 40Hz. Fronts being PSB T6 connected to channel A and B5 to channel B. This is the first time it has switched off like this. There is ample ventilation from all sides. I was a surprised when this happened. Model is 7005 marantz AVR

Perhaps someone else can tell you better than me. I wonder (suspect) that maybe when both are on, then it connects the L to L in parallel and the R to R in paralell? That could cause the amp to become unstable. I guess it either does that or loops the signal to another amp channel. Probably a good idea to read up on the manual.

 

[XEagleDriver]

Slippery has it right

Perhaps someone else can tell you better than me. I wonder (suspect) that maybe when both are on, then it connects the L to L in parallel and the R to R in paralell? That could cause the amp to become unstable. I guess it either does that or loops the signal to another amp channel. Probably a good idea to read up on the manual.

Slippery's comment is on target. The A/B speaker connectors are connected in parallel to one set of amplifiers. Therefore, when connected as described the impedance seen by the receivers amp section is lower than the lowest of either the T6 or B5 and this caused the problem you encountered at high volume over time (too much current and too much heat).
- The manual probably specifies a higher minimum impedance when using both A&B then when using either A or B speakers.
- A much better solution is to connect the B5s to the surround speaker connectors, hence a separate set of amplifiers, and when you want to listen to an "all stereo" mode just select it -- on some receivers it is called "5 channel stereo" or "seven channel stereo", etc.

Cheers,
XEagleDriver

 

[Jeff R.]

I believe you are correct, I did some investigation while looking at dedicated stereo recievers for a 2 channel and a outdoor system that I wanted to play both at the same rate. Most that I looked into did double up the load on the amplifier. There was not a separate amp for each A and B speaker set. I believe it will put the speakers in parallel and thus drop the resistance for your system. Hence why it may have shut down.

 

[Sylar]

Makes sense. Thanks!

I should have thought about this since Sometime earlier I had to replace the internal transistor for Left Front channel, because the speakers had shorted. During this time, both A & B went out. It means it is playing from same channel connected in parallel with a reduced impedence. I should have been more careful before connecting both A & B.

I presume i should not have much issue when I play with crossover at 100, or am I wrong. Either way, the B5 is now connected to surrounds channel.

 

[KEW]

I presume i should not have much issue when I play with crossover at 100, or am I wrong. Either way, the B5 is now connected to surrounds channel.

That would unload the amp somewhat, but unless you have charts of frequency vs. impedance (and phase), there is no way to know that the impedance drops occur below the 100Hz crossover. Generally, if both pairs of speakers were a steady 8 ohm load you would have no problems with any reasonable AVR.

 

[lie495fc]

quite interesting stuffs here. what if it's a Yamaha RV990 front A and B connected to Polkaudio RTi6 in a bi-amp configration. "A" to woofers and "B" to tweeters. would it damages the speakers?

the back of the receiver says:
A OR B: 5 ohm MIN. /SPEAKER
A + B : 12 ohm MIN. /SPEAKER