It's Transporter time! In order to do the measurements, I brought the gear downstairs to the basement which is an electrically quieter environment. There's a Belkin PureAV PF60 power center there for all the equipment. Also, the measuring computer is now an AMD Phenom X4 laptop with Win 8 usually used by my kids :-). The laptop was running on battery - I could detect a 0.5dB difference with the AC adaptor plugged down at the -110dB noise level.
One note about the XLR measurements you'll notice - the THD levels are a bit higher than RCA. I believe this is a result of the fact that the E-Mu 0404USB could not handle the XLR voltage from the Transporter and I had to use the analogue attenuators (just barely!) avoid clipping. Lets start with the 44kHz signal: 14421 Undoubtedly, the XLR output is significantly better than RCA. One observation is that through the RCA's, the stereo crosstalk remained around -90dB whether the signal was 16 or 24-bits. I'm not sure if this is the limit of the Transporter itself (even the humble AUNE X1 could do a measured -95dB), or has to do with the cables I used - a pair of AudioQuest 6' interconnects. I don't remember which model of AudioQuests these were (bought a few years ago in a moment of weakness :-) but they are longer than the 3' I had been using to measure upstairs. Now for 24/96: 14423 Again, we see the -90dB stereo crosstalk limit with the RCA output. XLR's measure is fantastic! Likely hitting the performance limits of the E-MU 0404USB and ~3dB better than the Essence One (of course the E1 did not have the benefits of a power filter or low noise environment of the laptop running on battery). The WiFi router was in the same room as the Transporter hence the 90+% wireless strength. No difference in the measurements whether WiFi or ethernet. To show in graph form the difference in noise floor between the RCA and XLR: 14422 Notice the noise spikes like at 60Hz using the RCA cable (the AQ construction seems to be shielded but can't confirm unless I cut it open!). Conclusion: 1. Overall the Transporter measures very well! Phenomenal XLR performance - best I have been able to measure so far. 2. A bit unclear about that stereo crosstalk measurement with RCA however. Seems a bit higher than I'd have expected. Might need to try a different cable and see... (In case anyone wondering, I have not opened up the Transporter to change the unbalanced volume attenuation.) +-------------------------------------------------------------------+ |Filename: 96_Results.png | |Download: http://forums.slimdevices.com/attachment.php?attachmentid=14423| +-------------------------------------------------------------------+ ------------------------------------------------------------------------ Archimago's Profile: http://forums.slimdevices.com/member.php?userid=2207 View this thread: http://forums.slimdevices.com/showthread.php?t=97950 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
