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Posts: 13629
Location: Vermont
Joined: November 12, 2007
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Thanks for the link.
The review is consistent with my experience, at least where there is overlap. (I don't have a Firewire adapter yet, so I haven't tried that.) With regard to the required break-in time, I would say that the unit kept getting better for at least two months, and that was with it powered on 24/7, and playing music at least four hours every day. I run a Windows 7 64 bit system. Playback with a juli@ on this system was unsatisfactory with the initial 4 GB of RAM, with a general feeling of edgy sound coupled with the occasional obvious glitch in playback. It did not sound "right" until the RAM was upgraded to 12 GB, after which it sounded better than my previous WXP 32 bit system with 1 GB of RAM. Since this memory upgrade happened six months prior to getting the Mytek, I have not tried going back to a "mere" 4 GB of RAM, but I suspect there would be similar problems when using the Mytek. I have the "preamp" version of the Mytek and I have the analog outputs of the juli@ wired into the analog input of the Mytek, so I can monitor the output of my cassette deck when digitizing tapes.
The Mytek USB interface requires a special driver on Windows systems. This driver barely works with cPlay, because cPlay does not correctly implement the ASIO interface. In addition, cPlay doesn't support DSD, so this software has become obsolete and its icon no longer gets any space on my desktop. Instead, I have been using HQPlayer, which has no problem playing PCM and DSD files via the Mytek. I have found with this player that the best sound on PCM recordings is to use HQPlayer to upsample to DSD128 and send that to the Mytek. I suspect this is because I found some filters in HQPlayer's large inventory that work better with my system. Although the Mytek won't play 352.8 and 384 kHz PCM, files at these sampling rates can be played by upsampling to DSD64 or DSD128. Upsampling to DSD128 sounds smoother than upsampling to DSD64.
I have a number of DSD downloads from Blue Coast Records and Channel Classics. These have excellent sound when I use HQPlayer to send these directly to the Mytek in their DSD64 format. It was also possible to get Foobar2000 to play DSD directly, but there were glitches such as audible clicks when starting and stopping DSD tracks, so I abandoned use of foobar2000 for this purpose.
HQPlayer has a good convolution engine that I have been using for playing PCM files. My small listening room has three room modes and by measuring these I devised minimum phase equalization that removes these peaks, giving me flat response at my listening position. This works when playing PCM at all rates and doesn't add much CPU load with my first generation core i5 processor. Unfortunately, to get digital room correction when playing a DSD file it is necessary to convert to PCM. HQPlayer can be configured to do this, so it is possible to play DSD files by converting them to 176.4 PCM, applying room EQ, and then sending DSD128 to the Mytek. One can also listen to this conversion process with the room EQ disabled, and thereby hear the audible degradation when downsampling the DSD. At present, therefore, I have a tradeoff to make when playing DSD files. I can play them direct without any room EQ or I can downsample to PCM and apply room correction. Which way sounds better depends on the individual recording. In the case of the Channel Classic chamber music recordings I have found that the direct DSD method gives the best results because these recordings don't have a huge sound stage. For the Channel Classic orchestral recordings, such as the excellent newly released Mahler 1, there is a huge expansion of sound-stage when the room EQ is used, with the walls just behind my monitors disappearing. There is a chance that the next version of HQplayer will include digital room correction at 2.8 MHz and if this will work (depends on CPU speed) this will probably remove this quandary.
This setup has a few interesting features that don't directly add to musical enjoyment, but which do provide useful diagnostic features when trying to fine tune a computer audio system. HQPlayer does PCM upsampling at a high level and when playing very loud PCM recordings there is the possibility of digital clipping. The user interface keeps a counter of the number of times this has happened during a playback session. In the event this counter increments one can then choose to apply digital volume reduction with the player's volume control. The Mytek USB driver has counters of interface errors. These enable you to tell if the computer is failing to service the DAC in time. If one hears a glitch in playback this is sometimes useful to examine, i.e. one can tell if the glitch was due to a system problem or just a bad recording.
There are a lot of options with the Mytek DAC that can be set from the front panel. It took me about an hour to sort through how the menu system works, but this was not easy without applying the RTFM remedy. I run the Mytek direct to my powered Focal speakers, so I use the built in volume control. I have the DSD filter configured to the 70 kHz bandwidth as any high frequency crud from DSD doesn't seem to bother my Focals. I have the PCM filter set to the slow setting, which works well when playing hi-res PCM directly. I use HQplayer to upsample 44.1 material to 176.4 or DSD128, so I haven't done any critical listening of filter settings at this sample rate.
Since I got the Mytek I have doubled my time spent listening to music as nearly all my recordings sound wonderfully musical. I also use this setup to do mastering of new recordings and remastering of old analog recordings, and this setup is very revealing of any defects in recordings. What is almost magical is the ability to reveal the defects in a recording while still producing musically enjoyable sound. About the only thing I don't like about the Mytek is that it makes a loud noise when switching in/out of DSD128 mode. This can be a bit scarey if the analog gain in one's preamp is cranked up loud. Starting and stopping in PCM mode is completely silent and there are only quiet noises when starting and stopping in DSD64 mode. I am told that there were similar noises in earlier firmware when starting and stopping in DSD64 mode and that the remaining problems with DSD128 will be removed with a future release of firmware.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
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