[GeneA]

I have recently bought an Onkyo C-S5VL and WA6 with EML 274B rectifier (about 2 weeks). My Headphone in HD-800. Today I decided to for no good reason try the headphone jack on the Onkyo which has internal amplification (with actual volume knob for headphone out). To my surprise going aback and forth I could not discern major difference between Onkyo and Woo. I tested these on several 24 bit recordings that I have.
 
Is something wrong with my setup? Or Onkyo internal amplification that good. This post is by no mean to criticize WA6. I am just trying to get some clarification.
 
 

 

[Cataphract]

Match their output volume within 0.1dB and double-blind test them?
 
From an objective standpoint they may both very well be transparent. In my experience quite a few receivers' headphone outs either have a problem with high noise floor/hiss, or high output impedance which reduces bass response on lower-impedance headphones. A subjectivist might like to claim one to sound more refined than another, but this nuance has a tendency of suddenly becoming inaudible when the listener can't see the price tags.

 

[GeneA]

Today I asked my friend to tell me any difference as I switch between the two and  extremely pay attention to any subtle changes, again my friend could not.
 
I decided to test my HD-800 on my one year old Denon receiver Headphone output jack. Now this time the sound was utterly horrid and terrible no comparison not even close enough to WA6.
 
I wonder what circuitry Onkyo has dedicated to the headphone out on my SACD player.