Yamaha RX-3060 with Yamaha M-40 power amplifier issues

[hunzman]

I have a 7.4.1 system consisting of a Yamaha RX-a3060 receiver with Martin Logan Motion 40 fronts, a Martin Logan Motion 50 XT center, Martin Logan LX16 surrounds, and Martin Logan electromotion IC overhead atmos speakers. The receiver handles the system well without any issues but it requires an external power amplifier to power two of the speakers for the full 7.4.1 setup. I just purchased a used Yamaha M-40 power amplifier which has 500 watts of power and is capable of 3 channels A, B, and C. I hooked up the fronts to run through the M-40 amp and the rest of the system is powered by the receiver and when I tested it I only hear sound on the fronts when the amp has the levels at 0. When I turn the L and R levels up on the amp there is no sound. I think this is really strange and intuitively I would have thought that it would get louder if the levels are turned up. The other thing I wanted to do was basically bi-amp the connection using 4 connections from channel C to the front left tower speaker and 4 connections from channel B to the right front tower speaker coming from the amplifier but this doesn't work at all. Do anyone have any idea what the issue could be? The amp seems so easy with hardly any buttons. Maybe the amp is not powerful enough? Although I would think 500 watts would be perfectly fine for just two tower speakers. Any ideas would be appreciated. I have attached pics of the amp. Thanks.

 

[lovinthehd]

That's not really a multichannel amp, more of a 3 zone amp. See the restrictions on impedance when running channels simultaneously? It may be another issue, but did you calibrate with YPAO or otherwise when adding the amp? I wouldn't bother with the bi-amp thing but read this and judge for yourself https://www.audioholics.com/frequent-questions/the-difference-between-biamping-vs-biwiring

 

[hunzman]

That's not really a multichannel amp, more of a 3 zone amp. See the restrictions on impedance when running channels simultaneously? It may be another issue, but did you calibrate with YPAO or otherwise when adding the amp? I wouldn't bother with the bi-amp thing but read this and judge for yourself

Thanks for the response. I did the test tone and the external amp speakers were not as loud as the other speakers powered by the 3060 so I switched the external amp to the Rear Atmos speakers just because I care more about the fronts. I think when I did the YPAO it compensated for the power difference. Still perplexing that I can only get the external amp speakers to have sound when the level switch is all the way to zero. Regarding bi-amping I guess I'll just forgo it at this time. One question: do you know if there is a cheap amp that would be better for powering my fronts? Got the M-40 for $230 on ebay and I thought that was a lot for a really old amp. Also, the bi-amping thing really doesn't make a difference? Why do people do it then? Why are there even 4 connectors on the back of the fronts?

 

[lovinthehd]

You're using the reply box incorrectly since you're mixing my comments with yours as a "quote" from me. Your response seems to be:

Thanks for the response. I did the test tone and the external amp speakers were not as loud as the other speakers powered by the 3060 so I switched the external amp to the Rear Atmos speakers just because I care more about the fronts. I think when I did the YPAO it compensated for the power difference. Still perplexing that I can only get the external amp speakers to have sound when the level switch is all the way to zero. Regarding bi-amping I guess I'll just forgo it at this time. One question: do you know if there is a cheap amp that would be better for powering my fronts? Got the M-40 for $230 on ebay and I thought that was a lot for a really old amp. Also, the bi-amping thing really doesn't make a difference? Why do people do it then? Why are there even 4 connectors on the back of the fronts?

What do you mean you "did the test tone"? Yes, different amp/gain structure matters. That's why you should run YPAO unless you have better ways of measuring. Try that and report back.

 

[AcuDefTechGuy]

Looks like the M-40 is 120 Watts x 2 Ch into 8 ohms.

https://reverb.com/item/3016604-yamaha-m-40-power-amplifier-120-watts-x-2-8-ohms-serviced-reconditioned-big-power

And I think you mean your system is a 7.1.4 (3 fronts + 4 surrounds, 1 subwoofer, 4 ceiling speakers)?

I would let the RX-A3060 power 9 speakers and let the M-40 power 2 of the ceiling speakers.