Hi Søren,
in my case the situation of PCM stream playback has improved. Unfortunately, the problem (clicks on start of track) still exists in DSD stream.
Black Friday and Cyber Monday Specials
From Friday Nov 23, 2018 to Monday Nov 26, 2018 we're having a special discount of 15% on the dac1421, dac1541, dam1921 and dam1941. See Soekris Engineering ApS, Ordering for information about where to take advantage of this special offer.
From Friday Nov 23, 2018 to Monday Nov 26, 2018 we're having a special discount of 15% on the dac1421, dac1541, dam1921 and dam1941. See Soekris Engineering ApS, Ordering for information about where to take advantage of this special offer.
Hi Soren,
I'm planning on swapping my regulator for the new Salas 1.3 and I was hoping that a 25VA toroidal would support a dual mono configuration. The dam1021 manual states max power and typical current draw, but I was wondering if you know what the peak rating is for each rail?
Thanks!
Michael
I'm planning on swapping my regulator for the new Salas 1.3 and I was hoping that a 25VA toroidal would support a dual mono configuration. The dam1021 manual states max power and typical current draw, but I was wondering if you know what the peak rating is for each rail?
Thanks!
Michael
Finally added a regulated +/- 7V DC PSU to the DAM1021. Big difference to unregulated AC! The cluttered midrange and stressed high end is gone. Good recordings sound stunning - alive, deep, clear and effortless.
What's the ideal value of DC to feed to the DAM1021? Currently I'm using the 8V transformer, so in order to get a sufficient voltage drop for the regulators to work I had to lower the output to the lower end of the recommended range.
The opamp buffers (need them) end up with less than +/- 6 V DC this way measured wrt the PSU ground. Ideally I would like them to be at +/-15VDC (clearly not possible), but I would consider the +/- 9V DC I got from the unregulated input the absolute minium.
What's the ideal value of DC to feed to the DAM1021? Currently I'm using the 8V transformer, so in order to get a sufficient voltage drop for the regulators to work I had to lower the output to the lower end of the recommended range.
The opamp buffers (need them) end up with less than +/- 6 V DC this way measured wrt the PSU ground. Ideally I would like them to be at +/-15VDC (clearly not possible), but I would consider the +/- 9V DC I got from the unregulated input the absolute minium.
+-7V DC is fine, less heat in the 3.3V linear regulator. The output buffer opamps are opa1602, they're rail to rail output types so they will do just fine at the lower voltages....
If you really want to you could remove R10 & R19 and feed the output buffers seperately....
See silk screen print, up around the large capacitors, should be the same on all revisions.
Update questions
Dear Soekris, First thank you for sharing your DAC development with fellow DIYers. I am interested as your board is what I am looking for. I have some questions.
1) I see from the earliest dates that your audiophile DAC initiative is nearly a decade old, as I saw 2009 as dates. This raises question s, in that Digital technology had dramatically marched on since then. Are your DAC chips upto date. Also clock jitter specs in DAC chips have gone way down over these years. So a question naturally arises again, are the digital components used in the current board, upto date????
2) MQA is coming in , will your DAC board be MQA enabled now or in the future?
etc???
Thanks for your reply.
Regards
Dear Soekris, First thank you for sharing your DAC development with fellow DIYers. I am interested as your board is what I am looking for. I have some questions.
1) I see from the earliest dates that your audiophile DAC initiative is nearly a decade old, as I saw 2009 as dates. This raises question s, in that Digital technology had dramatically marched on since then. Are your DAC chips upto date. Also clock jitter specs in DAC chips have gone way down over these years. So a question naturally arises again, are the digital components used in the current board, upto date????
2) MQA is coming in , will your DAC board be MQA enabled now or in the future?
etc???
Thanks for your reply.
Regards
I have been working on a little side project, now it's time to present it for everybody here....
It's a DAC module based on a discrete R-2R sign magnitude DAC design, with FPGA based reclocking and custom digital filters, < 1 ps jitter clock generator, with 28 bit resolution so there is headroom, oversampling up to maybe 3.072 Mhz. Up to 24 bit / 384 Khz input from SPDIF, I2S and USB (via USB to I2S interface board), with isolation on the I2S interface. The board will be very flexible, with digital volume control and filter parameters that can be downloaded, a possibility is also to add digital crossover filters, but that will probably not be ready for first production lots, although the board is firmware upgradable over a simple serial connection.
The basis R-2R network has an output voltage of 1.4V RMS and output impedance of 625 ohm and can therefore drive a lot of things directly.... There is also onboard balanced output drivers that can drive high impedance (>= 300 ohm) headphones directly. The power supply is also onboard, just add a 5W toroid transformer.
It is a small mostly surface mount PCB, and yes, I have working prototypes, see below.... But it's not really something for home assembly, with the FPGA in BGA package and 600 pcs SMT parts.... So yes, if there is enough interest it will go into real production, with sales though two existing online shops in US and EU.
Performance of first prototypes using 0.05% resistors is better than expected, see 1 Khz -1 db and -60 db FFT plots. I believe that the sound quality will be the absolute best, better than any Delta Sigma DAC, in class with discrete DAC's from totaldac and msb technology. And for way way less cost
----
Update on Apr 29, 2018:
Vers. 1.19 firmware with with filters now available on Soekris Engineering ApS, R-2R Sign Magnitude Audio DAC
The dam1021 have been shipping as rev 5 for a while, but no major updates, just production related updates.
Update on Oct 14,2016:
The dam1021-12 and -05 are in stock again, still rev 4.
Update on May 27, 2016:
Vers. 1.06 firmware with DSD support now available on Soekris Engineering ApS, R-2R Sign Magnitude Audio DAC
Boards from next production run will be rev 4 and are now in stock, that batch will only be the 0.05% and 0.01%/0.02% resistor version, which will be the only two dam1021 versions available long term. The only other change from rev3 to rev4 is a change in the output buffers, the LME49710/LME49724 is replaced with OPA1602.
Pricing for board rev 4 is:
dam1021-12: USD 295 / EUR 266 (0.01%/0.02% resistor version, in stock)
dam1021-05: USD 195 / EUR 176 (0.05% resistor version, in stock)
Pricing for board rev 3 is:
dam1021-02: USD 265 / EUR 238 (0.02% resistor version, very low stock)
dam1021-05: USD 195 / EUR 176 (0.05% resistor version, sold out)
Shipping cost and any sales tax and/or other local taxes to be added.
They are available to order though two existing webshop:
404 Not Found for American and Asia markets.
Soekris Europe » for EU and European markets.
The main Soekris Engineering ApS (Denmark) website for product and technical information is:
Soekris Engineering ApS, R-2R Sign Magnitude Audio DAC Please don't email soekris.com or soekris.eu with technical questions....
See also post #901 http://www.diyaudio.com/forums/vend...-magnitude-24-bit-384-khz-91.html#post4197094 for a quick drawing with connections.
And post #1108 http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-111.html#post4202602 for SPDIF interface drawing.
And great info here https://hifiduino.wordpress.com/2015/01/30/building-soekris-r-2r-dac/
Post #1486 http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-149.html#post4216998 with filter tools.
Post #3276 http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-328.html#post4421518 Firmware revision 0.99 update
Post #3295 http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-330.html#post4421780 more info on 0.99
Post #3108 http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-311.html#post4392832 Official vref modification
Post #3362 http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-337.html#post4425324 More info on vref mods
Anybody can now order the dam1021 R-2R DAC board from the two webshops.
This is old but still valid point IMHO
IS MQA DEAD ON ARRIVAL?
Is MQA DOA? - Benchmark Media Systems
IS MQA DEAD ON ARRIVAL?
Is MQA DOA? - Benchmark Media Systems
Things have elvolved the last 5 years, see the dam1941 for the newest OEM/DIY module.
I don't see anything obsolete in my DACs, the Sign Magnitude R-2R principle is still the best and done correctly with discrete parts it gives the best sound....
I will never decode MQA in hardware, will never pay to license such crappy encoding, it's just a new crappy DRM infected compression format, a step back, we don't really want any new DRM and we don't need compression that much anymore with internet speed going up everywhere, I finally go 100 Mbit/sec here.... I you insist to pay for MQA music just decode it in software.
Look around the net for informed opinions, not PR crap from the sellers and you will undestand it too.
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VRef modding:
Hi all, I checked and my DAC should be rev.4 or 5 as there is only a single op amp per buffered output channel.
I successfully modded my DAM1021 with 12 pcs of 16V/2200uF cap.
The bass, soundstage and dynamic I mean everything came with huge improvement! I enjoy it.
I will continue the mod with 4 extra caps (of the same uF) near the output. My question is: are the polarity correct? They don't have label for me to follow. Thanks for the help.
I have a RPi3 using Moode v3.84. I up-sampled to 32bit/352.8KHz and there is an obvious SQ improvement; but the DAC filters seem disabled(cycling through the filters usually have audio clicks but not anymore and hear no difference). I will stay that way for my RPi3.
This Dac is amazing! Love it
Hi all, I checked and my DAC should be rev.4 or 5 as there is only a single op amp per buffered output channel.
I successfully modded my DAM1021 with 12 pcs of 16V/2200uF cap.
The bass, soundstage and dynamic I mean everything came with huge improvement! I enjoy it.
I will continue the mod with 4 extra caps (of the same uF) near the output. My question is: are the polarity correct? They don't have label for me to follow. Thanks for the help.
I have a RPi3 using Moode v3.84. I up-sampled to 32bit/352.8KHz and there is an obvious SQ improvement; but the DAC filters seem disabled(cycling through the filters usually have audio clicks but not anymore and hear no difference). I will stay that way for my RPi3.
This Dac is amazing! Love it
Attachments
If you end up feeding separate +/-15V to the opamps then there is very little reason to not go straight +/-5V for the dam, then bypass bridge rectifier and both onboard 7x05 regulators. A general observations over the years is that there is more bass to be had the more you tank up the vref rails be it with caps and/or super regulator. The super reg was a time before the current production vref with low output impedance however it is known to improve things so long as you dump the 7x05 regulators upstream.
On my own setup I can still see the vref dip at higher volumes on the uV scale even with the super regulator and straight 5V so to see more caps improving the response on a stock dam1021 v4/5 isn't so surprising.
Also note the onboard mute circuit is locked muted at 5V inputs and there isn't a known way to make it work other than by using a muting relay which I better prefer anyway as it's not an active device the signal chain.