Comparing SNR on Amps

I'm not positive whether this post belongs here, or in the Gear>Amplifiers section...

I'm comparing the SNR on two amps. One is rated at -105 dB (ref 400 mV), and the other says >93db, unweighted, referenced to 1V RMS. Is this an easy, straight comparison (as in 105 vs 93) or is there anything else I need to be aware of when comparing these figures?

 

spec numbers, some of the greatest sources of mis-information and bad comparisons. One of the reasons I started measuring for myself. Graphs are more useful. Very few of those published. The >93dB unweighted referenced to 1Vrms is probably more honest than the -105 (no weighting specified) ref 400 mV. I'll bet the -105 is dB A-weighted. A-weighting yields better numbers as it can hide 1/f noise. So the >93dB is possibly better in this one attribute, though not necessarily. But there are a large number of attributes to consider beyond SNR. One I have come to appreciate is how well distortion matches between channels. You won't find this shown for any amplifier except measurements you find on the forums. Measurements can tell you if anything is seriously wrong with an amp, but only spending time listening can tell you if a given amp is the right one for your system. Going to meets, if possible, can be informative in this respect.

 

@atomicbob Thank you, this is very helpful.

I agree, there's definitely a lot more to an amp than it's SNR, but for whatever reason I've always appreciated it when an amp can shine in this particular area - without picking up any other glaring faults. Any suggestions for amps that might fit this bill?

I wouldn't necessarily need a powerful amp since I have a pair of efficient MDR-7506 headphones which I use at work. But I'm also curious if there are any amps capable of comfortably powering the HD650 that shine in this area - again without picking up any glaring faults...

 

Look at this chart to see headphone sensitivity vs. power required to achieve very high sound levels:
http://www.superbestaudiofriends.or...tem-synergy-special-sound.54/page-2#post-4328