Picked this beastie up from fleabay.... great value!   I happen to alread have an audiophile 24v PSU - the Creek OBH2 which I use with my Creek phono pre...   So I matched these together and started listening   I have no baseline for comparison yet, but it is driving my Revox 3100 (1986 Beyer DT880's) HP's very well, and making very nice sounds ..... Review and comparisons to come....   Update - the power supply makes a noticeable difference.... 

So listening to various discussions on Receivers and built in headphone jacks, with some people saying the resistor based HP Jacks are superior to the opamp based jacks - I thought I would put it to the test and ordered this little unit...   With the right cables (4xbanana to 1/4" TRS) this connects to the speaker output of a receiver, integrated or power amp and drives your headphones (up to 2 sets) directly.   It is simply a resistor network, including a passive resistor pot to adjust volume.   I also have a Firestone Audio Cute Curve...

Thought it great until I recently comparered its analog out to the DAC on my Onkyo TX-SR876 receiver...   Although good to a point, it failed in highly complex loud music passages like the Choral movement of Beethoven's 9th Symphony..... where as the volume and the number of instruments and voices increased, the 2496 could not keep the sounds seperate.... they become muddled/mixed a little muddy.   Under all other conditions, and especially with Jazz, small acoustic, baroque music, there was no discernible difference between the two.  ...