This is DIY! With your excellent work on the filter side one would think you would be more perturbed about having to do that instead of supplying output muting relays!
If someone was to make the DAC as a finished product they would have a relay circuit on the output. Transparent relay circuits are not simple. The device I pointed to is what Dave Davenport uses in his DAC line stage and has evolved over time. He used to incorporate the relays into the line stage and let them be powered by the DC filament supply (I think I am remembering correctly) but found it needed its own power supply (regulator) to sound its best. This is not a throwaway, as with anything in audio there are unwanted effects that must be minimized
I cannot stand relays, even the one above, and am grateful they are not incorporated into the board. Even used to shunt the signal to ground they have an effect on the sound when open. Especially those tiny enough to be used on board, I can only imagine.
One's small enough to fit on the board are very suspect to my severe case of audio nervosa.
Having amplifiers with delicate output devices I always turn the amps off first and then leave the DAC on continuously. Though I did accidentally turn the thing off and nothing happened but that sound. Wasn't THAT bad.
I remain concerned that whatever could be incorporated into the board to eliminate this could make things worse. How invasive would the code for this be? I prefer minimizing that kind of thing in a perfectionist product. If the DAC were to be used in a car radio who would care or be able to hear it anyway?
AS with any audio device the SOEKRIS is benefiting from use. Sounded good to me from the first using upsampled files, I agree 16/44 files sound not so good. All of my digital music files were with cues per cMP so I am having to start over, anyway. Why not make them 24/196 as cheap as storage is?
Hope to eventually figure out how to use the series port but it is not the most important thing, yet. My MB with the series output died and now I have to use USB.
After burning in the hardware with standard mains supply for two weeks and playing music with the NOS "filters" by spzzzzkt and upsampled music (384 KHz) I must say that this a very, very capable dac. It beats a lot of things I've listen to in the last years. I'm using a high efficient tqwt loudspeaker with fullrange driver which is very sensitive to localization of instruments and the coherency of the music. It's very detailed with a plausible room information and a top analog like sound. The dac can easily be used in long listening sessions with great satisfaction. I agree in opinion with rickmcinnis that changes should be done carefully to not destroy the basic characteristics.
Would you like me to send you the Hypex UcD180HG +HxR module that the "insignificant" power down pop killed in my amp?
I ended up having to replace both modules as the board I had was an older revision. So your "nothing to worry about" cost me close to the original purchase price of the DAC in repairs to my amp.
Power down protection is based on supply voltage. Once voltage drops below a certain point, you remove power from a NC relay. Muting is done by shunting the output to GND when the relay is closed - this was the method used by the Pass Labs D1 and others so has hi-end "cred". There is no need for code or relay contacts in the signal path. If it was extended to muting during unlock, you would use the same code that is in place for the lock/unlock LED to close the relay.
Last edited:
This being DIY audio, I find it funny for something made almost entirely of through-hole components and a few SMD devices that you couldn't replace those blown components, rather instead buy new complete boards.
I don't think there is any reason to pick on spzzzkt. He has contributed extensively to the development of the DAM1021. Anytime something goes wrong you will feel frustrated. He is just venting a tad.
I don't expect a perfect products from independent small vendors and i think most people should cater their expectations that way... especially if you don't know how some folks don't know how to connect power supplies to the DAM1021. For those just hang back a tad until all the knowledge is out (or the manual).
Peace all!
P.S. spzzzzkt thanks for your work on filters!
I don't expect a perfect products from independent small vendors and i think most people should cater their expectations that way... especially if you don't know how some folks don't know how to connect power supplies to the DAM1021. For those just hang back a tad until all the knowledge is out (or the manual).
Peace all!
P.S. spzzzzkt thanks for your work on filters!
This is what the bottom of one of my UcD400HGs looks like:
I imagine that the 180HG is pretty similar.
Can you really blame spzzzzkt?
P.S. Sorry for the OT..
So I just have to convert all of my 25,000+ redbook files in order to make this dac sound decent?
Piece of cake.
Would you care to reveal the names of these dacs? Were any of them discrete r2r-ladder dacs or just the usual sigma-deltas?
Without knowing the reference dacs, statements like these are of absolutely no value for me.
So far in this thread I’ve only come across one person (apart from myself) who had any experience with a TotalDac (or any other r2r-ladder dac) which was a brief encounter at an exhibition as I recall it.
For what its worth. After playing with different filters (still "mine" sounds best to my ears 
- subjective - I know....)
Running i2s in , 7.5Vac direct to the dam module and unbuffered rca to amplifier (no digital volume)
Raspberry pi2 - USB out - Gustard U12 - i2s"lvds" out - i2s "lvds" in dam1021.
This sounds better by a quite big margin than my "uber tweaked" Audio Note dac (ad1865 r-2r). 6463 analog stage. AN silver PIO at the outputs etc. (only one cap costs more than the whole dam1021 chain...
Thanks again Soekris.
And spzzzkt keep up the good work.
- subjective - I know....) Running i2s in , 7.5Vac direct to the dam module and unbuffered rca to amplifier (no digital volume)
Raspberry pi2 - USB out - Gustard U12 - i2s"lvds" out - i2s "lvds" in dam1021.
This sounds better by a quite big margin than my "uber tweaked" Audio Note dac (ad1865 r-2r). 6463 analog stage. AN silver PIO at the outputs etc. (only one cap costs more than the whole dam1021 chain...
Thanks again Soekris.
And spzzzkt keep up the good work.
For what its worth. After playing with different filters (still "mine" sounds best to my ears
Which is your filter and where can I get it?
Very, very similar, but the UCD180 boards are smaller and more densely packed...
There is also a potted daughter board that carries the core parts for the board.
but yes very, very OT.
Attachments
Last edited:
I built the 0.01 version yesterday. Compared to my Salas Reflektor-D powered and GaryB modified Subbu V3 , it has less harsh high end but I think less tight bass. Sounds seem to be much more natural, focus is better defined and soundstage is bigger. This is more obvious when the dac is fed with 24/96 and up music. Right now I use the original filters of firmware 0.8, powered by just a 2x7.5 AC transformer, single ended, driving my truepath and maggies smg-a speaker. Hope that there is more to gain with a Bib PSU.
TotalDAC
Am I wrong to think that one needs more than 0.01% resistors to resolve 16 bits let alone 24 bits?
Resistor ladder - Wikipedia, the free encyclopedia
Here Vincent Brient of TotalDAC says, "It is a 24-bit network although 0.01% resistors can not easily give a resolution higher than 14 bits"
Vishay Precision Group - Foil Resistors - Case Study: Developing a Multi-Channel DAC for High-End Audio Applications
Am I wrong to think that one needs more than 0.01% resistors to resolve 16 bits let alone 24 bits?
Resistor ladder - Wikipedia, the free encyclopedia
Here Vincent Brient of TotalDAC says, "It is a 24-bit network although 0.01% resistors can not easily give a resolution higher than 14 bits"
Vishay Precision Group - Foil Resistors - Case Study: Developing a Multi-Channel DAC for High-End Audio Applications
Monotonicity/linearity and resolution are not really the same thing. The sign-magnitude design of the Soekris DAC gives some advantage in that the MSBs are not having to switch nearly as much. I am sure Soren explained this somewhere early in the thread.
Which is not to say that the board really has 28-bit resolution. It probably falls somewhere between 16-18 bits.
There is and was no intention of giving spzzzzkt a hard time about the relay thing I was simply making a point about relays being on the board and my general disdain for relays. When I read these forums spzzzkt's posts are among those I find to be the most important these days. I wish I could do what he has done and continues to do
Though I have not had the opportunity to try his filters yet due to my own inability to load them I am grateful for his efforts.
My only intention was to say SOEKRIS had not made a design faux pas in my own unhumble opinion. It was a choice and I think he made the correct one. Just an opinion.
I do not think I suggested nor recommended anyone reload their libraries in 24/196. I mentioned why I was doing this - it takes less time to "rip" the files again than to "cut" my cue based files. I thought it important to explain why I find the DAC to sound really good and do not doubt this has bearing. Simply a full disclosure ...
AS far as having 50,000 titles in one's collection - I do not think I could ever decide what to listen to with that amount of choice. I guess I am lucky I border on the autistic in having a much more limited view of what is worth listening to along with what is worth keeping. If my digital music was not in cue format I would be more annoyed at the prospect of beginning again.
My system is horn based with low power amps so that may well explain the reason I did not experience the same tragedy. I feel very lucky.
Nonetheless, my only intention was to mention that the thing IN THIS CIRCUMSTANCE sounds pretty damn good to me. After listening to nothing but LPs for the last two years I was worried I would be very disappointed in what I would hear. In combo with the new JPlay Beta I am staggered by how good it is. Digital sound quality has assuredly got much better since my last system.
I am concerned that we may have jumped to conclusions about the DAC before letting our boards fully settle in. As with any device, this DAC is getting better with more time running.
I was among the most anxious to screw around with the board and now I am glad I have taken SOEKRIS's advice to listen to the thing first before messing with it.
There is not a doubt in my mind that a separate relay muting circuit is superior to anything SOEKRIS, or anyone else, could cram on to the board.
Of course, spzzzzkt did not realize this was a problem until it was too late for his amplifiers and who would not have empathy? I certainly did not intend for it to sound like he should have known if that is how my comment was taken, nor to cast aspersion on his abilities to set up a system. Did not even occur to me until reading responses that my comments could have been taken in this way.
I mentioned the output devices in my amps only to make the point that BECAUSE OF THAT I always (well, not always as I admitted) turn the things off before switching off anything before them. When I pulled the plug on the DAC I had visions of boxing the things up to ship to California (again) for replacing the output devices. It was my lucky day.
Though I have not had the opportunity to try his filters yet due to my own inability to load them I am grateful for his efforts.
My only intention was to say SOEKRIS had not made a design faux pas in my own unhumble opinion. It was a choice and I think he made the correct one. Just an opinion.
I do not think I suggested nor recommended anyone reload their libraries in 24/196. I mentioned why I was doing this - it takes less time to "rip" the files again than to "cut" my cue based files. I thought it important to explain why I find the DAC to sound really good and do not doubt this has bearing. Simply a full disclosure ...
AS far as having 50,000 titles in one's collection - I do not think I could ever decide what to listen to with that amount of choice. I guess I am lucky I border on the autistic in having a much more limited view of what is worth listening to along with what is worth keeping. If my digital music was not in cue format I would be more annoyed at the prospect of beginning again.
My system is horn based with low power amps so that may well explain the reason I did not experience the same tragedy. I feel very lucky.
Nonetheless, my only intention was to mention that the thing IN THIS CIRCUMSTANCE sounds pretty damn good to me. After listening to nothing but LPs for the last two years I was worried I would be very disappointed in what I would hear. In combo with the new JPlay Beta I am staggered by how good it is. Digital sound quality has assuredly got much better since my last system.
I am concerned that we may have jumped to conclusions about the DAC before letting our boards fully settle in. As with any device, this DAC is getting better with more time running.
I was among the most anxious to screw around with the board and now I am glad I have taken SOEKRIS's advice to listen to the thing first before messing with it.
There is not a doubt in my mind that a separate relay muting circuit is superior to anything SOEKRIS, or anyone else, could cram on to the board.
Of course, spzzzzkt did not realize this was a problem until it was too late for his amplifiers and who would not have empathy? I certainly did not intend for it to sound like he should have known if that is how my comment was taken, nor to cast aspersion on his abilities to set up a system. Did not even occur to me until reading responses that my comments could have been taken in this way.
I mentioned the output devices in my amps only to make the point that BECAUSE OF THAT I always (well, not always as I admitted) turn the things off before switching off anything before them. When I pulled the plug on the DAC I had visions of boxing the things up to ship to California (again) for replacing the output devices. It was my lucky day.
For what its worth. After playing with different filters (still "mine" sounds best to my ears
Running i2s in , 7.5Vac direct to the dam module and unbuffered rca to amplifier (no digital volume)
Raspberry pi2 - USB out - Gustard U12 - i2s"lvds" out - i2s "lvds" in dam1021.
This sounds better by a quite big margin than my "uber tweaked" Audio Note dac (ad1865 r-2r). 6463 analog stage. AN silver PIO at the outputs etc. (only one cap costs more than the whole dam1021 chain...
Thanks again Soekris.
And spzzzkt keep up the good work.
Out of curiosity, why are you running a USB-i2s board out of the Pi rather than going straight into the DAM's i2s from the Pi's GPIO i2s out?
red book from circa 1984
time to go to hdtrack and download some amazingly well recorded music...
start with this album:
http //www hdtracks com/top-hi-res-female-vocalists/the-absence
track 5 and 9 were an epiphany for me, especially the note decay...
put the red book stuff in your car.
a+
Martin
start with this album:
http //www hdtracks com/top-hi-res-female-vocalists/the-absence
track 5 and 9 were an epiphany for me, especially the note decay...
put the red book stuff in your car.
a+
Martin
Last edited: