Vintage DACs

Discussion in 'Digital: DACs, USB converters, decrapifiers' started by Luckbad, Apr 26, 2016.

  1. Biodegraded

    Biodegraded Friend

    Pyrate Contributor
    Joined:
    May 28, 2017
    Likes Received:
    7,985
    Trophy Points:
    113
    Location:
    Vancouver BC
    Please guide me, o wise ones...

    I'm considering an Assemblage DAC 2 with upgrade kit (fancy caps, resistors, wire, connectors) as a replacement for Modi Multibit.

    It'd be fed, as the Modi is now, by a CD player via coax and by an RPi-S/PDIF streamer. Currently the streamer's transport is a HiFiBerry Digi +, which is connected via optical because the DAC has only one coax input. Because the Assemblage has BNC as well as RCA (and optical) inputs though, the HiFiBerry could sometime be replaced with the reportedly better sounding Allo Digi One.

    Downstream items are a Rotel integrated to Dynaudio bookshelf speakers, and MCTH to HD6XX.

    The asking price for the Assemblage seems good - same as I paid for the used Modi Multibit c. 18 months ago.

    Thoughts?
     
  2. rlow

    rlow A happy woofer

    Pyrate Contributor
    Joined:
    Jul 18, 2017
    Likes Received:
    7,738
    Trophy Points:
    113
    Location:
    Canada
    I saw that one. Looks very interesting and a good price. Hopefully some here will be able to give you a sense of it.
     
  3. Mr.Sneis

    Mr.Sneis Friend

    Pyrate
    Joined:
    Oct 2, 2015
    Likes Received:
    1,321
    Trophy Points:
    93
    Location:
    Phoenix, AZ
    I'd go Assemblage in a heartbeat. Big but. Keep in mind it uses opamps for IV and Output buffer. You can change the sound for better or worse with some pairs of single opamps. If you choose a non specced proper pair the dac will oscillate and that will show up as piercing highs, too much treble, or extreme bass bloat.

    I spent a lot of time the past year or so learning to mostly hate the sound of opamps. I feel like I can spot an opa627 blind and I'm just not a huge fan of them despite their reputation.

    If you dont roll, the dac will still sound pretty good in stock form.
     
  4. Andre Y

    Andre Y Friend

    Pyrate
    Joined:
    Oct 4, 2015
    Likes Received:
    220
    Trophy Points:
    43
    Location:
    Southern California
    All the DAC talk in the SBAF DAC thread made me pull out my old Muse Model 2 and hook it up: it's the OG version with the DF1700 filter (I think, but definitely not the PMD100 HDCD filter) and PCM63 PKs. It has the crappy CS8412 receiver, but Muse tweaked it for a lower PLL cutoff and the Eitr should be giving it a clean signal.

    It can only do up to 48kHz and probably 20 bits, but seems to accept 24 bit inputs. It's a nice change after listening to an early Modi Multibit for my desktop setup (home speaker system uses an Yggdrasil A2), and sounds very nice: bass is more controlled, details are there, but aren't shoved in your face. Instrument placement is precise and tight over an SDR HD800. I would say the rendering style is that things are just there, and you can listen to them if you want or ignore it.

    Had to dig up an old BNC-RCA cable since it only has BNC inputs, and I'm driving it from an Eitr and a 2017 MBP over USB. I have AudioMIDI setup for 48 or 44k.1Hz: it will downsample all hi-res files so it works on this DAC, but most of my library are CD rips. I'll probably listen to it for a while.

    For you old Sun workstation dudes who remember SunOS, Kevin Halverson (Muse owner and designer) was one of the first people to put out an I2S standard cable using the 13W3 connector which later upgrades to this DAC has. The 13W3 connector was the video connector for old Sun workstations. Google for it, but it looks like a wider VGA connector with some mini coax inside along the regular pins.
     
  5. winterfog

    winterfog Facebook Friend

    Contributor
    Joined:
    Dec 5, 2018
    Likes Received:
    169
    Trophy Points:
    33
    Location:
    Hawaii
    A month after I wrote my initial observations of the Counterpoint DA-10, it's become clear that the "slight lift in the high end" I was hearing with the DA-10 was DEFINITELY a consequence of not enough warm-up time. The DA-10 needed way more warmup than I expected. After a month plugged in, the perceptions have flipped--the DA-10 now has a slightly warmer tone than the Modi Multibit. The DA-10's highest-highs are now extremely pleasant and smoother/finer than the Modi Multibit's. Air, tone, weight/body and microdynamics/plankton have all improved significantly, and so the gap has widened between the DA-10 and Modi Multibit. I find myself losing my critical awareness and just grooving out to the music with the DA-10 in a way I don't with other DACs, which is the biggest compliment I can give it. I'm not sure how much warmup time was enough, but I definitely didn't have enough when I wrote my initial observations.
     
    Last edited: Feb 13, 2019
  6. winterfog

    winterfog Facebook Friend

    Contributor
    Joined:
    Dec 5, 2018
    Likes Received:
    169
    Trophy Points:
    33
    Location:
    Hawaii
    Nice. My Counterpoint uses the CS8412 receiver and DF1700 filter as well. Do you mind explaining what's crappy about the CS8412? Poor jitter attenuation?

    I bought pin-compatible drop-in replacement boards off eBay to replace the socketed CS8412 with the newer CS8414 and the DF1700 with the DF1704... I didn't note any definite audible differences from the switch, just maybe a small improvement in signal lock-on and a possible improvement in low-level detail refinement that could conceivably correspond to lower jitter. (No way to A/B and the difference, if any, wasn't large enough to be otherwise confident that it's not just placebo.)
     
  7. Andre Y

    Andre Y Friend

    Pyrate
    Joined:
    Oct 4, 2015
    Likes Received:
    220
    Trophy Points:
    43
    Location:
    Southern California
    The actual measured performance is pretty bad, but in general it's a single PLL so its loop filter's high pass point has to be pretty high (around 10kHz) so that it can lock onto all sorts of crappy transports. Muse just tweaked the PLL loop constant to slightly lower its high pass filter, so it's probably still pretty bad. Some people implemented a second PLL with a much tighter filter (eg. Meridian 563 which went down to maybe 10 Hz? I can't remember now.) after the 8412 to help it reject jitter better. Other people (eg. ML 31.5) had their own clocks inside the DAC and used a memory buffer to smooth out clock differences. Not sure what the Theta DACs did.

    I think the 8414 added 96kHz support, but is otherwise the same. Maybe some of the PLL stuff was improved too.
     
  8. Mr.Sneis

    Mr.Sneis Friend

    Pyrate
    Joined:
    Oct 2, 2015
    Likes Received:
    1,321
    Trophy Points:
    93
    Location:
    Phoenix, AZ
    Has anyone here swapped a ST optical or SPDIF optical input for a BNC? What would be involved?
     
  9. fastfwd

    fastfwd Friend

    Pyrate
    Joined:
    Aug 29, 2019
    Likes Received:
    993
    Trophy Points:
    93
    Location:
    Silicon Valley
    Wow, people are still listening to the DA-10. That's awesome.

    I have a few DAC cards for that thing in storage somewhere, along with some bare and partially stuffed boards. If I find them I'll post here; maybe they'll be useful to someone.

    Anyway, in case you haven't found more info in the last few months, the trim pot is for adjusting the DAC's most-significant-bit voltage. An error there manifests as distortion right around the zero-crossing, so it disproportionately affects the quality of low-level signals. It's easiest to trim the voltage if you have an oscilloscope, but you can also do it by ear, by playing quiet low-frequency sine waves and turning the pot until you hear the purest single tone.
     
  10. fastfwd

    fastfwd Friend

    Pyrate
    Joined:
    Aug 29, 2019
    Likes Received:
    993
    Trophy Points:
    93
    Location:
    Silicon Valley
    So I found some Counterpoint DA-10 DACCards:

    DA10-A020
    Dual Analog Devices AD1862 (20-bit, R-2R, current output).
    Activates the DA-10's MSB trimpot.
    This is the card that @winterfog already has.

    DA10-CS18
    Crystal Semiconductor CS4328 (18-bit, 8x interpolation filter followed by 64x delta-sigma DAC, voltage output).

    DA10-BB69
    Burr-Brown PCM69 (18-bit, R-2R for the upper 10 bits and delta-sigma for the lower 8, current output).
    Although the PCM69 is a current-out DAC, I-to-V conversion is performed on the card, so the card is voltage-out.
    My card is missing the opamps for the I-to-V conversion, but they're socketed so someone just needs to choose an appropriate part number and plug them in.

    [EDIT 2020-06-23: The original opamps were the LT1115.]

    DA10-UA20
    I have two of these, only partially stuffed, and unfortunately they're missing the important bits: the UltraAnalog D20400 modules.

    [EDIT 2020-06-23: Didn't see that the 14-pin socket on each board was empty. The missing IC is a 74HCU04 hex inverter.]

    All but the DA10-A020 have installation manuals. I don't have a DA-10, so none of these cards have been tested.

    @winterfog (or anyone else who owns a DA-10): With the understanding that none of these cards are guaranteed to work or even to not damage your DA-10 -- want any of this?

    [​IMG] [​IMG] [​IMG] [​IMG]
     
    Last edited: Jun 23, 2020
  11. fastfwd

    fastfwd Friend

    Pyrate
    Joined:
    Aug 29, 2019
    Likes Received:
    993
    Trophy Points:
    93
    Location:
    Silicon Valley
    Nobody wants these cards? If I can't find someone who can use them (in a DA-10, not for parts), they're just going to go back into storage...
     
  12. klyrish

    klyrish Facebook Friend

    Contributor
    Joined:
    May 4, 2018
    Likes Received:
    167
    Trophy Points:
    43
    Location:
    Nowhere
    Anyone have experience with the Adcom GDA-600? I found a used one on Audiogon last week and snatched it up so I could finally experience the much-lauded Burr-Brown PCM63 DAC. It just arrived about 15 minutes ago. I've gotten it setup on my desk, it's plugged in and turned on, and I've attached the coaxial-out from my Eitr to both coaxial inputs on the DAC and...nothing.

    No signal is being detected on either port. I connected everything back up to my Onyx to ensure nothing funky was suddenly happening and immediately, music was coming through my headphones.

    I've ensured that the amp is on the SE-input (not balanced) and have tried both coaxial ports multiple times to no avail. There's apparently a "digital frequency lock" LED on the front of the GDA-600 that lights up when a source is detected on the chosen input and that's never lighting up.

    The seller said this worked (albeit they only ever mentioned the optical-in and I no longer have my optical cable or Behringer adapter) and I've emailed them asking what's up, but this doesn't look promising.

    Is there any trick to this DAC that maybe I'm not aware of? It's quite cold since we've been in the low-20s all day during this massive blizzard, but this doesn't seem like something that would only start working after warming up. Maybe, but unlikely. Any other possible things I could check/try to get this working? I REALLY want to hear this DAC. It was only $215 with shipping but this is still incredibly disappointing, especially after the shipment was delayed three days.

    EDIT: A-HA. I don't know how to do this in Spotify, but in Roon, I had to do "Device Setup" on the Eitr zone and limit the Max Sample Rate to 48kHz in order for the DAC to pick up the signal (it was set to 192kHz).
     
    Last edited: Nov 26, 2019
  13. murray

    murray Friend

    Pyrate
    Joined:
    Sep 29, 2015
    Likes Received:
    478
    Trophy Points:
    63
    Location:
    N.Z.
    I have a GDA-700 which is different internally. However, it has a max of 48k sample rate which will be the same as the unit you have, and the reason you had to drop it down to that. Limits of 48k and 24-bit were common back in the early 1990's.
     
  14. murray

    murray Friend

    Pyrate
    Joined:
    Sep 29, 2015
    Likes Received:
    478
    Trophy Points:
    63
    Location:
    N.Z.
    It shouldn't require any warming up unless the power supply capacitors are shot. They could be, as the unit will be over quarter of a century old.
     
  15. klyrish

    klyrish Facebook Friend

    Contributor
    Joined:
    May 4, 2018
    Likes Received:
    167
    Trophy Points:
    43
    Location:
    Nowhere
    Thanks for the responses. I'm glad that's all it was (dropping the sample rate) and it makes sense given the fact that at the time of this DAC's release, it would've been fed by Redbook CDs, MAYBE HDCDs but I don't know anything about those or what their output rates were.

    Despite being ice cold, I was really enjoying what I was hearing. I'm feeding it a usable signal from Roon and will be for the next few days now. Looking forward to revisiting in 24 hours or so after it's warmed quite a bit more.
     
  16. Azimuth

    Azimuth FKA rtaylor76, Friend

    Pyrate
    Joined:
    Nov 9, 2015
    Likes Received:
    6,839
    Trophy Points:
    113
    Location:
    Nashville, TN
    Home Page:
    We forget sometimes the most these vintage DAC's can do is 24/48, lol.
    Warm up time on those is only an hour or so. It is with my Denon AD-500 with the PCM1702, the chip that replaced the PCM63. If any coldness after 24 hours is likely the Adcom op-amps. They were very picky and most were LT op amps in a class A bias. My Adcom GCD-575 with the TDA1541 is cleaner that most TDA players.
     
  17. klyrish

    klyrish Facebook Friend

    Contributor
    Joined:
    May 4, 2018
    Likes Received:
    167
    Trophy Points:
    43
    Location:
    Nowhere
    I've been listening to the Adcom GDA-600 a lot since getting it last week, through both headphones (HE6se) and my Edifier S1000SD active speakers now that they're back in my office after being retired from backyard patio duty for the winter...

    I'll keep this short, especially because my Headamp GS-X mini should be shipping soon and I think that'll really show what this thing is capable of, but even through the THX AAA 789, I'm constantly impressed. Detail retrieval is excellent, shockingly near Onyx levels...maybe 80-85%, great timbre, incredible separation and positioning (especially through speakers), a much wider sounstage than the Onyx, and oh my, that BASS. I've been on a kick of 2008-2012 metalcore lately which saw the scene totally abusing and overusing bass drop trigger pads on pretty much every single album released during that time, and through the Edifiers especially, the rumble is INSANE. The Onyx doesn't do a great job of separating the bass drops out from the rest of the bass frequencies, but for whatever reason, the GDA-600 makes it very noticeable and powerful. Bass in general is so much tighter and punchier and even seems to reach a bit deeper with the GDA-600 than the Onyx.

    The last time I used these speakers with anything but my phone, it was on my Modi Multibit -> Vali 2 stack and they sounded fine. Having much higher-end gear has really shown me what I'm missing with speakers and these aren't exactly reference speakers (though, they are excellent for the price). Everything sounds so much more massive, powerful, separated (especially on the dense Onyx), and part of a greater whole. I still love headphones but I will definitely be using speakers a lot more in the future.

    I really like this DAC a lot and completely understand the PCM63's place in DAC history now. It's unreal the GDA-600 is, what, 26 years old or so, and still holds its own against the latest and greatest of today. And to think this wasn't even that high-end either... Can't wait to hear it through an amp with proper balls!
     
  18. klyrish

    klyrish Facebook Friend

    Contributor
    Joined:
    May 4, 2018
    Likes Received:
    167
    Trophy Points:
    43
    Location:
    Nowhere
    I've had a Theta DSPro Basic IIIa for about a month now and finally hooked it up to my modest HT system (Denon AVRS740H, 2x Klipsch R620F, R-34-C, 2x R-15M) after being moderately underwhelmed by it in my headphone setup, and holy shit...

    I get it now.

    I remember @purr1n saying somewhere that people who don't use the Yggdrasil in a speaker setup are only getting about 60% of it and I feel that applies here, too, with this DAC. As great at the GS-X mini -> Ether 2 chain is, this is so much better in every single way.


    In stereo mode on the receiver (no DTS or multi-channel stereo processing), this DAC is blowing me away. Bass is out of this world and the sub isn't engaged at all and these are the lowest-end floor speakers Klipsch has. The Soundstage is enormous... It sounds like it's at least 5 feet out to the sides and maybe a foot or two above the speakers. I have checked repeatedly to ensure the center channel isn't engaged because vocals in particular sound like they're coming straight at me through it.

    Detail is astounding. I'm listening to NIN (obviously) and the little nuances of all the various layers are perfectly audible and beautifully separated while simultaneously remaining entirely cohesive. I've heard numerous little things that I've never heard before likely due to the small area headphones have to put everything out there. Very minor stuff like extra texture on synth patches that's just lost in the chaos but now have more room to project.

    The sub-bass in tracks like "We're In This Together," "Starfuckers, Inc.," and "Underneath It All" is felt in my chest like I'm at a concert. The beautiful main piano riff in La Mer sounds like it's in the room and the plucking of the standing bass is making things rattle. This is one of my all-time favorite songs and hearing it through this chain makes me feel like the ocean is washing over me when I sit back and close my eyes. The piano and droning guitar swim all around but the drums stay firmly center throughout.

    Listening to the 2017 Definitive Edition of The Downward Spiral sounds damn close to the 2004 5.1 surround mix in terms of positioning and imaging.

    I truly regret not hooking thr Gungir up to this system before selling it because this is effectively its great, great grandparent.

    I fear what this newfound experience with speakers is going to do to my wallet. My wife is blown away and totally down with turning the basement into a listening room with legit speakers once my brother moves out and this DAC is going to be the centerpiece of the system.
     
  19. RobS

    RobS RobS? More like RobDiarrhea.

    Joined:
    Feb 21, 2019
    Likes Received:
    1,419
    Trophy Points:
    93
    Location:
    .
    You had the Gungnir Multibit A1, right? Not a fan of it with NIN or other industrial and metal genres. I need punchier dynamics with those. Gungnir A1 is soft hazy easy-ridin' yacht rock. This is the main reason I had to pick up another Convert-2 again for those albums I need a dynamite punch. On some genres the Gungnir is great, especially the timbre of female vocals and piano. But it's weaker in other areas. I'm warming up a Yggdrasil A2 and barely a week in, it outclasses the Gungnir A1 in every possible way. These multibit dacs are excellent with the HD650s, still haven't decided on speakers yet. Gungnir A1 first night was amazing with some albums my girlfriend and I enjoy together, but the next day I listened again and it was "WTF?" on some different albums. Too soft and boring.
     
  20. klyrish

    klyrish Facebook Friend

    Contributor
    Joined:
    May 4, 2018
    Likes Received:
    167
    Trophy Points:
    43
    Location:
    Nowhere
    I'm shocked someone else agrees about the Gungnir; I honestly thought I was the only one and it was something wrong with me. And yes, I had the A1. Your comments about the Yggdrasil A2 piqued my interest but I wonder if Schiit just ultimately isn't the sound I want.

    I recall posts I believe you made about the Convert-2 and looked into it again just now... I'm very curious about it, especially since it seems to be dual AKM4399 chips. You honestly think it's better for the music we're into over a multibit DAC? I really want to hook the Onyx up tomorrow night to hear it through a proper(ish) system...

    And I just disabled the Audyssey dynamic EQ and wow...that opened the sound up so much. I was playing at 70dB and had to drop down to 52 becaise it was so much louder. Mids and highs that I didn't even know were being muted are suddenly THERE. This is so much fun to listen to.
     

Share This Page