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
McIntosh advised me to leave my former SS MC2250 (measured accurately at 305 wpc by them) set at MAX (seems a heck of a lot doesn't it), and then send/pass less from the preamp. SS amp was dead quiet at any volume setting.

Volume (less gain) needed by the preamp, either prior SS preamp, and importantly current Tube preamp, it's tubes need to produce less gain.

Things change when using tube amps. You need to find a/the combo of amp volume and pre-amp volume working together that is noise free.

Then, boost either the preamp volume, or, if integrated amp, boost it's volume, (or both within known noise free parameters) This affects equipment location (height of physical knob rotation or location of remote sensor).

Currently, my tube preamp at 11 am; tube amp at 12 oc. Then, for different cartridge outputs, and/or more volume, I can change either devices volume.

In my particular case, I go from preamp to a Chase RLC-1 remote line controller, then to amp. My volume is a combo of the Chase's default volume/preamps volume/amp volume, which allows me source/volume/balance from listening chair, thus different cartridge outputs, do not effect my paired preamp/amp noise free volume pairing.

Remote balance helps refine individual tracks that benefit a surprising amount from a slight balance tweak. Adjusting from the listening spot remotely makes it easy,
set amp gain at max unless you can’t, such as when you cannot achieve appropriate balance, or your pre is way too hot. Here is the basic technology you need to know to understand why:

The amplifier circuit’s gain (Vout / Vin) is always exactly the same, often around 23 dB of voltage gain. The volume knobs are just resistors in front of that. Often inexpensive and prone to degrading over time. By setting the volume to maximum you minimize the amount of those resistors in the circuit.

Best,
E
+1 erik,
These are resistors in the circuit, all the way up or remove them.
Many japanese power amps of the period had this extra feature, in fact you could connect a source like tape, radio, without having a preamp.

G
Thank you so much all... 

I know I am getting quality feedback (pardon the pun) because I have needed to reread the answers numerous times; why above my pay grade knowledge wise. but, I thoroughly get the gist of where I need to be with my Yamaha gear

I have maxed out the knobs to 5:00...

Since the Cerwin Vegas are rated with sensitivity 101db and the amp is rated at 200wpc I am truly cooking sonically with the volume at 7:30.  My ears are not trained or equipped to officially or  "technically" discern better sound...but whether it is the power-of-suggestion, or not... I think I can sense the sound has a bit more upfront punch...some warmth...allowing the vinyl to work well and sound good.

Listening to Petty.  With the gain adjustment...it seems that the muddy, sloppy and BIG "Dance floor'" CV D-8's are a bit clearer and cleaner. and they can stay.  I did want to move into the Klipsch range of speakers...Forte, Heresy, etc or their "flagship" towers the RF 7 lll.  

Because of my loot...I think my next step will have to be the cartridge.  Moving away from the Grado Platimum 1...into possibly a Hana MH or Hana ML...either the high or low output. Likely the high output to be able to stay with my MM Cambridge Solo Phono Stage.

The good news...I do have very quiet fans pulling warm air out and up from the amp and pre... I have heard these units can have a tendency to run a bit warm.  

Anyway...  What a hobby.

Thank you all again.

Sincerely,

vinylspin
You should always set the dials full open unless you have a very efficient speaker that would not let you use the preamplifier volume hardly at all. When you turn the gain on the amp down it can cause a loss of dynamics and contrasts in the music in some circumstances due to the attenuator used on the amplifier.