Amplifier knobs...where to "set" on the clock?


Here is a question that has idled in my head for years...

I have a 1983 M-70 Yamaha separate amplifier...paired with a C-70 pre. On the front of the M-70 are two sets of knobs for output...for the A and B speakers. I have never been sure on where to place the output line...as if on a clock.  A  "tech" friend told me that the knobs should be at straight-up "noon"...(not wide-open at 5:00)  He saying the reason: "Let the preamp do all of the work". Then, I asked the tech who serviced the M-70 and C-70 years later and he told me the knobs should be "wide open" at 5:00. no reason, except that is where they should be set.

Hmmm.

What do the fine people here at Audiogon say to those two opposing opinions?

What a hobby!

Thank you in advance.

vinylspin
vinylspin
Speakermaster...thank you...

With your advice...  To me...that would suggest that perhaps since I have a VERY efficient set of Cerwin Vega speakers...101db...Perhaps I should consider backing the gain off a tad...maybe from Full-On 5:00 to 3:00?  allowing the preamp to "breathe" a bit? Am I making sense?

Also...hobo1452...thank you
With your advice...to me...it suggests one of the reasons for the gain control at all is about a high wattage amplifier not over powering and "cooking" a vulnerable set of speakers... i can customize the output safefly and correctly...while still allowing the preamp to do its job.  Am I making sense?
vinylspin
As with many things, try the options and see. Noon? 5 o'clock? I bet your system works better at one of them.
In as much as I would agree the ideal would be not to have to attenuate the amplifier, a 200wpc amp driving 100dB speakers seems a mismatch. In your case, with the amp unattenuated you are using very little of the gain provided by the line stage of your preamp.

Given that you are reaching full volume at 7:30 with the amp at 5:00
I would try setting the amp such that equal volume is attained with preamp set around 11:00 and see what that sounds like to you. You would likely have better control over volume. If it proves detrimental to sonics then return to your current settings.




My McIntosh MC2152 does not have volume controls, but I have plenty of other knobs I can turn!