SBGK wrote: > how do you calibrate your measurements ? I can quite clearly hear that > different JPlay engines sound different, but your measurements can't > differentiate between them. What differences can your measurements > identify ? > > how about testing win 7 vs win 8, they sound different, would your > measurements identify any differences there ?
For a test like this one, it's very easy. Since it's all just digital data going into the DAC via USB and I'm measuring the analogue output, I manually ensure there's no clipping going into the ADC device. Typically 100% audio output (RightMark has a calibration signal for this) from the TEAC corresponds to -0.5dBFS for the E-MU 0404USB using the gain controls. Beyond that, I make sure there's no other volume changes going on between tests so everything is relative from that point. Any relative volume changes for example would be very easy to tell, especially if the output goes louder (>0.5dB) and starts clipping the device. I don't see how I would be able to differentiate Win 7 from Win 8 when there's no objective difference between Win 8 and Mac OS X using the asynchronous USB-to-SPDIF device... See: http://archimago.blogspot.ca/2013/04/measurements-laptop-audio-survey-apple.html Conclusion item 4. If you have a theory as to how / why it sounds different, I'll certainly have a look if it's doable. I can certainly accept that Win 7 and 8 can sound different with DirectSound since the algorithm could have changed in the mixer... But of course I can't imagine audiophiles use this form of audio output except for those who set the system up improperly! Archimago's Musings: (archimago.blogspot.com) A 'more objective' audiophile blog. ------------------------------------------------------------------------ Archimago's Profile: http://forums.slimdevices.com/member.php?userid=2207 View this thread: http://forums.slimdevices.com/showthread.php?t=98933 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
