Is there any "Reference Level" for Amps??

[avliner]

Hi folks,

yesterday finally I've got my power amp and so far, so good.
Matter of fact, my 1st option was a Behringer A500 and I had a $ 200 credit at Sam Ash, but they don't carry the A500, so I ended up grabbing a SAMSON, model Servo 300 ( 2 x 100W @ 8 Ohms ~ 2 x 150W @ 4Ohms ).

I'm really happy with this new baby and my first impression is that now the mains have more authority, specially basswise.

By this weekend, I'll be running a new test tone (with SPL + Avia) and I was wondering whether there's a reference level for the amp itself; I mean, at what position should I set the volume knob at the amp when running the test tone (minimum, halfway, maximum..)??

Any comments will be most appreciated.
Thanks in advance!

 

[Jack Hammer]

...By this weekend, I'll be running a new test tone (with SPL + Avia) and I was wondering whether there's a reference level for the amp itself; I mean, at what position should I set the volume knob at the amp when running the test tone (minimum, halfway, maximum..)??

Any comments will be most appreciated.
Thanks in advance!

I would check your manual to be safe, but all three amps I have owned have all recommended calibration with the knob turned all the way up (maximum). That's probably a good place to start.

Jack

 

[avliner]

Thanks Jack,

manual doesn't say anything about it, but I'll do that right now (I have both knobs set 2 positions higher than midway now).
Was enjoying stereo sound and the amp. really makes a difference...

Cheers.

 

[zildjian]

You need to check the level at which the output from the preamp to the amp. An amp is designed to perform ideally with a certain signal input level, obviously if it's too low, then you have to turn the gain up on the amp beyond what it should be to achieve a certain volume, and conversely over driving the preamp wouldn't be good either. Look at the specs for the amp, find the input sensitivity for the type of input (either balanced or unbalanced/direct) and there should be a voltage value such as... 0.6V rms (just an example value! look for your amp's specific value). That means your amp is designed to perform ideally with an input signal of 0.6V. Play a pink noise source through your preamp and measure with a sensitive voltmeter at the outputs the voltage level with the volume set on the preamp set to it's reference, "0 dB" or whatever it is on your amp, it would be turned up loud if playing music! Adjust your preamp's gain for each channel so that it's 0.6V.
After you do that, THEN you worry about the level at which your amp gain is set, and then, it's whatever volume you want out of it (of course within it's capabilities...).
Hope this helps,
Brad

 

[avliner]

Thanks Jack,

manual doesn't say anything about it, but I'll do that right now/QUOTE]

My bad,

after re-reading the manual, it clearly states on page 06:

"... for the best signal-to-noise ratio, the Servo Series should normally be run with the channel input controls at or near maximum..."

I'm running mine at the near maximum position and sound is amazing.

Cheers.