Post by sadface on Sept 6, 2018 16:58:30 GMT 12
Hey guys,
I've been pondering making one of these dacs for a few years.
Apparently they have sold a kit or 2 to New Zealand, I was wondering if anybody on here has any experience with them?
DDDac
Post by Owen Y on Sept 10, 2018 15:42:25 GMT 12
Hi sadface - back when I was researching my DIY DAC (around 2007), the DDDAC was a paralleled TDA1543 DAC - up to 12 of them as I recall.
DarkLantern blog - darklanternforowen.wordpress.com
7,244 posts |
|
Administrator
 Post by Owen Y on Sept 10, 2018 15:50:24 GMT 12
Stacked on top of ea other & heatsinked, as below.
DarkLantern blog - darklanternforowen.wordpress.com
7,244 posts |
Post by sadface on Sept 13, 2018 17:27:24 GMT 12
Hi Owen,
Those look rather hilarious. They are still using the basic concept of running dac chips in parallel. Now they are using the 1794 Dac chips in parallel. My current dac can only deal with up to 96khz/24bit. I have some music that is 192/24 and thus can't be played properly with wasapi, requiring downsampling. So I want a solution capable of 192khz operation which chops down the possibilities a bit. I also don't want up or oversampling as I don't need that extra rubbish in my signal chain. I'm yet to find another 192/24 dac that also does non-up/over sampling. I'm also here on the DIY forum so ya'll know that just buying a premade DAC is not an acceptable solution. I've been slowly replacing all my store bought stuff with home-made produce for a few years now. home-made valve preamp home-made valve monos home-made active crossover A DAC is the next logical step and the is current system bottle neck now that all that solid state rubbish has been expunged from the amplifying end. I do have dreams of a tube crossover too but that is another story. Also, eventually I think i will need a pilgrimage to Haiti to some upskill on Voodoo and make some speakers. 
424 posts |
Post by Owen Y on Sept 13, 2018 19:47:33 GMT 12
Hi sadface - with an active crossover, one of the Linkwitz DIY multi-amped dipole loudspeakers could be an option....
www.linkwitzlab.com We just today reported on his death, on our Siegfried Linkwitz thread. PS. Didn't Marchand used to offer tube (& SS) active xover kits? DarkLantern blog - darklanternforowen.wordpress.com
7,244 posts |
Post by sadface on Sept 15, 2018 11:06:03 GMT 12
Marchand still seem to be in business.
I'm running a Marchand XM9 SS active crossover right now. Runs fantastic, never skipped a beat. Marchand does offer tube crossovers but they are outside of my budget, starting at USD2000. I need to somehow save me an Auckland sized house deposit before She who must be obeyed starts producing hungry mouths to eat up my DIY budget. There is this though: www.ebay.com/itm/DIY-PCB-Stereo-tube-active-crossover/151098965212?hash=item232e333cdc:g:UykAAMXQBwlRSk7Q That is perhaps in my price range. A heck of a lot more work and goodness knows what the final parts cost would be after tubes, iron and chassis. Looks like a fun challenge though.
424 posts |
|
Administrator
Post by Owen Y on Sept 15, 2018 14:22:27 GMT 12
For active crossovers, I'd tend to go with SS, despite probable minor sonic consequences.
But I've no experience in this area. DarkLantern blog - darklanternforowen.wordpress.com
7,244 posts |
Post by cartridgeguyonline on Dec 22, 2019 9:22:03 GMT 12
Im interested in a DIY DAC too, if anyone has any experience of a good kit. Have even asked Santa for a new Soldering Iron (yeah like its the soldering iron thats the problem...).
941 posts |
Post by garym on Dec 22, 2019 12:27:52 GMT 12
When it comes to diy DACs it is a misnomer. Buying a kit is still buying something that is pre-made. The pcbs are all using surface mount parts so the scope for true diy is severely limited.
The remainder that is actually the diy part, power supplies, and assembly, just leaves plenty of room to screw it up. Having said that the best of this breed would be the Soekris R2R stuff. But you still need to know what you are doing because digital just isn't like analogue. My advice would be to just jump in, budget depending, on a Topping D50s, or D70, or the new AKM one that is about to be released. If your budget is greater than that then the field opens right up. 
Pureaudio
255 posts |
Post by sadface on Jan 8, 2020 18:29:25 GMT 12The remainder that is actually the diy part, power supplies, and assembly, just leaves plenty of room to screw it up. Having said that the best of this breed would be the Soekris R2R stuff. But you still need to know what you are doing because digital just isn't like analogue. My advice would be to just jump in, budget depending, on a Topping D50s, or D70, or the new AKM one that is about to be released. If your budget is greater than that then the field opens right up. Hi Gary, Thanks for the advice. I suspect that my initial attraction to the DDDac was because it is a bit more DIY. The real important stuff is SMT but the builder gets to populate the motherboard with their own resistors and caps etc to feel like they've built something. Some of the other designs I've been looking at are more along the lines of what you speak: a premade pcb one gets to implement into a box. Soekris R2R does look pretty good. I've also been eyeing up the Twisted Pear products Unfortunately for me, I've got that DIY bee in my bonnet. The idea of buying a retail product just doesn't appeal, compared to building my own stuff (even if it usually costs more by the time one is done). Due to my currently very full project list, its probably several years before I get around to trying to make a DAC. I've probably been putting off making a start on a DAC due to the difficulties you speak of.
424 posts |
Post by garym on Jan 8, 2020 18:40:03 GMT 12
The Soekris is the tried and tested one. 1941/1921 are everything important on one board. Just power supply to do.
The twisted pear ones tend to end up with a rats nest of interconnected boards with a lot of wire in between.
Pureaudio
255 posts |
Post by sadface on Jan 8, 2020 19:56:11 GMT 12
That makes sense regarding twisted pear, everything being separate modules. All that wiring could certainly leave room for errors.
A single board would be quite nice. It appears as though I would need to add an USB to I2S board as that is my preferred interface for simplicity. Soekris appears to recomend the DIYinHK board. Supply on the Soekris seems ticky to NZ. -The Chinese supplier has no english -The Vietnamese supplier doesn't have much info on stock and shipping. -The US supplier is out of stock. Looks like I would have to order direct from Europe. I have a spare chassis that has been waiting for a DAC for a long time. One of Simon's 120mm EzChassis from designbuildlisten.co.nz I want to eventually have matching boxes for DAC and preamp. I also have a matching plywood front panel for my Marchand crossover that I've never gotten around to implementing.
424 posts |
Post by colinf on Jan 9, 2020 0:05:32 GMT 12
I’ve been making dacs with the Soekris boards for a while now. The R-2R format means you don’t need an output stage, the output comes straight off the resistors. It has a slight design quirk that required me to add extra regulation for the power supply. You need to order it from soekris.dk.
  AMR-iFi R&D
1,406 posts |
Post by garym on Jan 9, 2020 9:43:53 GMT 12
The modules I mentioned have usb coax optical etc all on board. I wouldn't source these from Asia, just Europe or the USA.
Pureaudio
255 posts |
Post by garym on Jan 9, 2020 16:52:07 GMT 12
I think it's isolated, but you'd best check their specs.
Pureaudio
255 posts |
Post by jeb950 on Aug 12, 2021 11:37:27 GMT 12Hi there, What are these dacs that you make like? Tell me more?
52 posts |
Post by colinf on Aug 12, 2021 19:27:52 GMT 12
Hi jeb950, it’s basically a Soekris DAM1021 Dac module connected to the Amanero usb interface. I just put it in an enclosure. You can also use it without usb, with a spdif coax or toslink input, which is less costly. The usb input is galvanically isolated to stop computer bus common-mode noise at source.
But there’s a little more to it than that. I change the power supply to the clock source on the board, add a power pre-regulator and bypass the opamp output stage so that the output comes off the R-2R resistor network directly. It’s much more open sounding that way but lower in level, so you need to turn your preamp up a little more. I also add one more stage of passive filtering so that the HF steps don’t interfere with subsequent amp stages and make them generate IMD. It’s also not MQA certified and can’t decode it, as Soren doesn’t like the MQA algorithm. I have 2 here and use them with Qobuz on Hi-Res with Audirvana. AMR-iFi R&D
1,406 posts |
|
Connoisseur
 Post by colinf on Aug 14, 2021 19:30:02 GMT 12
I have a lot of dac designs here now to compare. The Soekris has that openness and subtlety while maintaining natural dynamics. It’s good because there’s no output stage and is all the more transparent for it. Almost all other dacs have an output stage whether it’s valve, discrete solid state, hybrid or opamp, for filtering. Without an output stage the output impedance is a little higher than normal so it’s wise to choose a shielded, short interconnect and use a preamp with no RF filter on the input as that can roll off the top end. No output stage also means less cost and smaller size.
I like the delta-sigma AKM dacs as well, they have that silky smoothness and linearity which betters the Soekris in some ways. But I keep coming back to the R-2R configuration, despite the higher distortion from the need to match the dac resistors to within an inch of their lives…0.01% precision needed. The shift registers that drive the resistors have their own resistance variation, making the need for precise resistors good up to a point. The resistor network is 28 bits long but the distortion is around 0.006%, just under a bit less than CD standard of 16 bit. CD is limited to 44.1kHz but oversampling makes the effective resolution higher, and the Soekris employs oversampling as well using an FPGA (field programmable gate array) with FIFO (first in first out) for processing. The Soekris can go up to 384kHz. The AKM measures 20 to 23 bits (depending on version) so has much better low level linearity and lower noise floor, and you can hear it in the ambience. I’d love to marry up the AKM with the Soekris with an FPGA to do the lower bitrate conversion. But that would need reclocking to maintain low jitter. So just leaving the Soekris design well alone for now! AMR-iFi R&D
1,406 posts |
|
Pundit
 Post by paulsaints on Aug 17, 2021 15:36:33 GMT 12
Colin - is the difference between the dac1421 and the dac2541 just the difference between single ended and fully balanced? or is there more to it than that? or maybe I misunderstood when you said earlier to get them direct from Soekris - are you making your own from their modules or making them up for Soekris?
195 posts |
Post by jeb950 on Aug 17, 2021 21:28:51 GMT 12Reading the description it states that the 2541 has 400 resistors where as the 1421 only has 200.
52 posts |
Post by colinf on Aug 18, 2021 0:11:44 GMT 12
The distortion is lower with the 2541 Dac, 0.004% as it uses more precise resistors (0.01%), and is also balanced with 28 bit configuration. Afaik in the balanced configuration the switching distortion reduces by around 3dB compared to SE. The 1421 has 0.02% tolerance resistors, SE and 0.008% distortion, with 27 bit configuration. The Dam1021 is SE with in-between distortion, 0.006% and 28 bit configuration. The 2541 and 1421 both have headphone amps built in.
I’m not affiliated with Soekris in any way, I just buy their modules and tweak them! You can still hear the transparency with even the lowly (!) 0.008% versions, just that the more precise ones seem to have better ambience. AMR-iFi R&D
1,406 posts |
