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

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.

 Speaker Level Controls:
In addition to speaker A/B selectors that permit one-touch selection of two sets of stereo speakers, the M-70 features independent level controls for the left and right speakers in two stereo pairs. That is, you have independent left and right speaker level controls for speaker pair "A", and left and right level controls for speaker pair "B". These controls let you independently set the maximum power level that will be sent to the respective pair of speakers, protecting low-power-capacity speakers from excessive power levels, or matching the output level of two sets of speakers of different efficiency. Independent control over left and right speaker level lets you preset the balance of your system for optimum stereo imaging depending on the positioning of your speakers and the acoustics of your listening room.