I received my Silver faceplate TubeDAC-11 on Feb. 1 (I posted pics on pg. 2 of this thread), & now have 150 hrs. or so of burn-in time. Chassis feet rocked ever so slightly at first which was easily remedied by pressing down on the corners to level out. I set the DAC-11 on a section of marble & used 4 vibrapod isolators under the DAC-11 for stability. Selector knob aligns properly w/ source choices (there has been a few reports of quality issues re: these items mentioned).
System details-
GR Research N-3 transmission line speakers w/ upgraded crossover Sonicap capacitors & bypass caps, No-rez cabinet damping material, & Electra Cable braided speaker cables
Virtue Audio Sensation M-451 T-Class integrated amp w/ Dodd Audio tube buffer- Psvane 12AU7-T tube & SLA battery-powered supply (2-12v 5 amp) incl. trickle charger
Oppo BDP-83SE blu-ray player incl. 2 ch upgrade w/ 8 ch Sabre Ultra ES9016 DAC chip
iMac 3.06 gHz 12 gb memory & 500 gb HD; 5 meter Belkin USB cable between DAC-11 & iMac
Decibel audiophile player (also auditioned Audirvana Plus); running 24/96 hog mode (exclusive rights obtained)
iPad2 used as w/ various remote apps for Decibel player, Spotify, iTunes
I’ve done some serious listening of late w/ the TubeDAC-11 (with & without tube). I experimented primarily w/ 24/96 material, some redbook material, Spotify, etc.
The Grant Fidelity TubeDAC-11 w/ 6N11 stock tube sounds very nice esp. so w/ 24/96 tracks … organic, slightly warm, airy, non-fatiguing.
I always have preferred tubes either in the amp or preamp, but not both. This was also the case in this instance. Utilizing tubes in both took away some of the detail & was too laid back. Bypassing the tube buffer on the amp & using the DAC-11 tube buffer was very good, but a tad thinner. Louder vocal passages were bit more shouty than the preferred method: Amp w/ tube buffer switched on & using the excellent Psvane 12AU7-T tube (acquired from GF) & DAC-11 DAC only bypassing the DAC-11 tube buffer. It was not a night & day difference, but improvement nonetheless.
I also preferred maxing out the DAC-11 pot & solely utilizing the ALPS motorized pot of the M-451 amp.
I did move the iMac close to the 2 channel rig & connected the USB cable supplied w/ the DAC-11. Using the same 24/96 source material, I could not detect an audible difference between the shorter & longer USB cables.
Comparing Marianne Thorsen/ Trondeim Solistene Mozart Violin Concerto 24/96 track thru the DAC-11 vs. Stereo DSD same track thru the Oppo BDP-83SE was interesting. They both sounded fantastic. I couldn’t consistently pick one better than the other. The Oppo Sabre Ultra DAC is revealing, but silky. The amp tube buffer helps smooth things out & probably masks some distinctions.
I don’t have a large amount of 24/96 material yet (maybe 50 tracks all told, classical, jazz) & what I do have is lacking in the rock/alternative area that I most prefer, so I still need to audition more.
For $325, this “swiss army knife” TubeDAC-11 is a real bargain for sure!