Initial listening impressions of the DAM1021-01.
Disclaimer - I have only been listening to this dac for about an hour, at the most, and not very intensively. No A/B reference testing yet.
My test setup - Squeezebox Touch USB out->Amanero I2S->DAM1021-01 onboard xlr out->Questyle CMA800R solid state headphone amp->Audeze LCD-3 (non Fazor vers.) I consider my LCD-3 rather laid back, which I like. And I’m also normally a tube fan. So now you’re warned.
No distortion whatsoever on low level solo piano music (sustained notes) like my old unipolar r2r dac had.
Very detailed, as in micro details - quite unsuspected from this type of dac.
Sound is quite harsh to my ears - dac probably needs to settle and get some more hours to burn in. Only about 24 hours at the time of listening.
Very up front sound signature, forward, in-your-face picture. Not very relaxed. (Which I quite frankly hate).
Wiiiide sound stage. Not much going on center. Very left/right orientation w. some music, at times it sounds almost as something is a little bit out of fase. Sound coming almost from behind rather than in front.
Focus on upper mid and treble. Less bass and oomph. Which is why I at first didn’t bother to try it with my electrostatic Sennheiser HE60 & Stax hybrid amp, as these stats are focused on the mid- & upper region.
A short click is heard when changing between tracks w. different sample rate and the FIFO takes a while to settle thus cutting off the beginning of the track. Sometimes the FIFO makes the music fade in lasting 1 second or so.
Apart from this the timbre of the instruments sounds right w. some air/spacing between instruments. Seperation could be much better though, like r2r dacs normally present.
Okay, so just by chance I swapped in my Senn stats and the Stax amp that has a tube output stage. (balanced input).
Accidentally I played a rock music track by Beck from Guero album (a music genre that not normally suits the Senns IMO). Lo and behold. All of the above impressions didn’t apply anymore!
Frequency spectre was much more linear w. a bass punch I’ve seldom heard from this setup. Lovely airy separation between instruments, more holographic like the r2r’s I’m used to. More laid back presentation. Quite relaxed.
In short, the whole system was playing MUSIC. Effortlessly.
Is this a synergy thing? Shifting from dynamic headphones(speakers) and solid state to stats and tubes.
Still, it’s VERY early days but this dac definitely has got potential.
Is there a default filter selected? Default oversampling & upsampling?
"The number of packages does not match the invoice, waybill, or label. We're working to resolve this discrepancy."
I have a new version of the FPGA firmware where the mute function should work much better, could somebody with the Amanero USB interface please try it ?
1) Download and unzip attached file 1021fpga_090.zip
2) Connect the dam1021 serial port to a PC serial port with a terminal program (I use HyperTerminal), set for 115200,n,8,1, no handshake.
3) Enter uManager on dam1021 by typing "+++" followed by a 1 second pause.
4) Type "download" and start sending file from the terminal program using 1K X-modem protocol.
Power cycle when done, you can verify by entering uManager again, FPGA revision should then be 0.9.
Assuming I use a DC power supply, I guess I need 2,5W for each of the symmetric supply voltages and 5W overall?
I could not help but think you are describing the effect of incorrect polarity.
If you have a way to invert polarity (which everyone should) I bet that recording might sound just fine.
Wish all resolving gear would include a polarity switch!
This DAC not having a balanced output makes it impossible to change polarity with a switch on the output.
Maybe your player has this function.
Maybe SOEKRIS can incorporate this into the firmware? Sure would be a boon to enjoyment of ALL recordings.
We're you using the same output off of the DAM 1021 in both cases? It seems like it, first you say XLR out, second time balanced out, which is the same, right? I wouldn't expect a big "synergy" difference, since both headlamps are SS. Possibly overloading in the first case? Or impedance issues? In any case, it's great that you got such a "musical" output. I've got my board in now, but still need to set up for input and power, so I'm a few weeks away at my slow pace.
... There is also onboard balanced output drivers that can drive high impedance (>= 300 ohm) headphones directly.