Soekris dac thread, dac1321 / 1421 / 1541 / 2541

Sovrce Gear
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I’m slowly building on this overview / review as I have time.

For now I have to start with a rant that I hope will be helpful to any future dac1321 owners (and other Soekris DACs).

TL;DR
Be very careful with the volume setting. It is not an analog output volume setting. It is an internal DSP volume setting. As such, if it is set to maximum there will be no headroom left for proper signal processing. This will drastically reduce sound quality. Read the Users Manual closely to set the volume to < 0dB (-3dB is a good rule-of-thumb) to ensure no clipping.

Excessively Angsty Rant Over Volume Control Issue

→ queue some angsty alt rock before reading further, I recommend Linkin Park, One Step Closer

PSA - Read the dac1321 Users Manual (very) closely! The volume control on this dac… oh… the volume control… I’m so angry right now!

I’ve had this little DAC for ~2 weeks. And my honest opinion up until about 1 hour ago was that it was good, but not great. No magic. But then I noticed something out of the corner of my eye, the volume LED flickered. (The DAC isn’t in my normal field of view while listening, and this little LED is usually blocked by my hand resting near the headphone amp volume knob.) I thought “wtf was that flicker?” So I started the track over and watched more closely, sure enough, not just flicker, regular blinking.

Re-reading the Users Manual: “CLIP” The Volume LED will blink RED when the DAC output signal is clipping. :thinking: ?Why is it clipping? :thinking: Then it slowly dawned on me… :thinking: :face_with_raised_eyebrow: :expressionless: :anguished: :angry: :rage:

But first some background info: the dac1321 is the stripped down, ultra minimal, entry level DAC from Soekris. Because of this the indicators on the front panel are very minimal. It’s fine, honestly much better than other entry level DACs, so no real complaints here. Other than the volume indicator solution they have: the brightness of the LED indicates the digital volume level, “from -80dB to +10dB”. 90dB of range is a little tough to indicate with LED brightness. So it’s imprecise to say the least. BUT 1 click = 1dB. So if you crank it many times one way or the other you can be confident you’ve pegged it out at one of the extreme ends. Then you get to count clicks until you get to the level you want. If you don’t want to deal with this every time you power cycle the DAC, set the volume where you like, hold the filter button down for 4 seconds, and it’ll save the volume setting. This is where my last two weeks have gone wrong…

I read the Users Manual wrong. I thought the process to get line-level output was turn the volume all the way up (crank it to the right many times until you were confident it was all the way up). Then hold the filter button down for 4 seconds to save it. done.

And overall the DAC hasn’t sounded great. I expected some “R-2R smoothness”, and really it sounded a little harsh. Not overly so, but definitely not sounding much better than other basic sigma-delta DACs I have kicking around. Honestly disappointed, but I was not really able to admit a bad purchase to myself yet… and then my volume LED flicker observation, Clipping!

Turns out my process of setting the volume saved it at +10dB, not 0dB. Shit. And really I want roughly -3dB to give the internal DSP some headroom. Double Shit. I thoroughly knee caped this DAC.

So I re-performed the volume setting ceremony: cranked the volume up to +10dB, and then very carefully clicked it down 13 times to -3dB, and saved it.

Turned the music back on, and sure enough, no flicker! And guess what! The music sounds GREAT! When you don’t peg out the digital volume control it leaves the DAC a lot more headroom to process data and sound like real music!

→ fade out the angsty alt rock, cut over to some good Blues Rock, Eric Clapton, Presence of the Lord

Thanks for listening to my excessively long rant.

Quirks and Features

More to follow, but without a doubt the volume control is a serious Quirk to be aware of.

Taking It For a Drive, How Does it sound?

A proper review to follow, but so far I’ve gotta say, this DAC is smooth… I’m really enjoying it. And after I spend some time listening with it setup properly I’ll report back with more impressions.

Conclusions

None yet, but so far so good…

Admin note: edited to include all soekris dacs

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This is amazing, more reviews should have mood based sound tracks!

This is a dac I would have been interested in if they weren’t like hens teeth now so I’ll look forward to your more sensible but less ranty impressions.

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Thanks, it was 1am when I wrote this rant/review/psa, so I’m mostly lucky it was cohesive :joy:

With a slightly more clear mind this morning I put it behind a “Hide Details” block. Most people won’t need a hyper emotional rant, but just the useful / actionable information.

It really is a nice little DAC, and it’s unfortunate it’s become so hard to find.

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I believe the volume thing is how he gets better dynamic range out of his R2R ladders, he basically relies on the fact music doesn’t use all the bits most of the time, so he’s boosting the volume to get more linear response for small signals, where it’s hard to make a for a traditional r2r ladder that’s accurate.

I used a similar trick many years ago when mixing audio signals for computer audio where we didn’t even have 8 accurate bits.

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Is this style of volume control unique? Having volume at the start of the signal processing chain, not the end, is backwards to how I usually think. It makes sense to do it this way, especially given your explanation. But if you aren’t careful (which I clearly wasn’t) it seems like a disaster waiting to happen. (or maybe it’s just me :man_shrugging:)

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I was surprised when I first saw the volume thing reported, it is common for some volume to read the difference from 0dB, putting digital gain on the input signal to a DAC, I’ve only ever heard of on the Soekris products.
The fact you can clip the output by doing it has always seemed “broken” to me, and potentially dangerous, though in practice something downstream will probably filter out enough of the bad signal to prevent damage.
It’s expensive to make an accurate R2R ladder with discrete components, and you’ll see a lot of tricks in higher end devices to get there, If it improves the overall linearity, and more importantly the way it sounds, it’s a good hack.

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After 2 weeks of not enjoying this DAC and seriously considering selling it, I would agree, this is “broken”. Especially with the poor volume indicator, it’s very hard to know if you’ve got it set right. It feels like “faith-based volume settings”. But now that it’s set, it sounds great.

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The other models in the Soekris series - dac14xx and up, have a display that makes it easier for you to see where your volume is set. I had both a 1321 and 1541 at the same time and I do agree it was a bit more difficult to set the 1321 because I was having to rely on “counting clicks” using the pot. I did get it dialed in and fine tuning was done by playing some tracks that tripped the “clip” light to flash only in rare instances and seemingly out of the blue for that track. I’d then dial back the pot one step rinse and repeat until it did not clip, and then left that setting. On the 1541 it was similar process though much easier as I could see if I was -3, -4 etc. etc. so my starting point was easier to set. For myself , system and that unit -4dB was and is where it is set now.

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Has anyone else tried using a 3rd party power supply with this DAC? I’ve tried both the Allo Shanti and iFi iPower X with it. Both seem to change the tone of the DAC, moving it from neutral/warm to leaning bright and sharp. The Shanati was the worse of the two, but the iPower was still uncomfortable to listen to.

If anyone has found a 3rd party supply that sounds good with this DAC I would be interested to know.

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Wish I could help, but I wasn’t a believer yet in psu’s when I had the 1321 so I only used the one provided.

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I have a 1321, but don’t have any alternate PSUs to try with it. I’ve always felt it was more bright and edgy leaning in stock form, though, so if that’s what a PSU change does, not sure I’m inclined to try rolling.

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I’ve found this little guy to be very “needy”. Setting the volume to -3dB/-4dB to prevent clipping, using the stock power supply, and even some sensitivity to USB supply noise (changing USB source from laptop to a network streamer running on a low noise supply made audible differences). Maybe Coax / Toslink are less “delicate”? But right now I’ve got it sounding really good: detailed and leaning slightly warm, so I REALLY don’t want to touch anything…

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Nice! Yeah, I recently picked up a Pi2AES I’m going to try out with the Coax SPDIF, but upgrading from generic USB cable to a Mad Scientist Black Magic was a very noticeable improvement.

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I’m definitely curious to hear your thoughts on sound differences (if any) between SPDIF and USB. Pi2AES is on my list of streamers to try.

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Hello,

Has anyone tried or heard of this Dam Dac from Soekris?

Uses this as an example predominantly also not badly constructed from the power supply point of view.
It is also available with a Pi as a streamer.
Basically, it’s not bad in principle, but also very expensive, if you know a bit about what the Dam Dac, Pi costs, and the power supply itself probably won’t cost a fortune either.
The price of the device is a bit exaggerated.
Nevertheless, they tend to turn up cheaper on Ebay.
The equipment in terms of connectivity is also a bit undersized, unfortunately.

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I haven’t personally heard the board Acuhorn uses (pretty sure it’s the dam1121) but I have it’s upgraded version, the dam1941. It sounds really great even with the bare minimum to run it (no fancy psu or output stage). I would put it at like a slight notch above an Ares II in terms of performance, although, when I had both of them in the house I didn’t do that many comparisons, so take it with a grain of salt. But still, I would say that they are at least on a similar level.

In general Soekris dam boards have a nice following in the diyaudio community and are well regarded, especially the dam1021/1121 which have been around for longer than the 1941.

If I recall correctly the 1021 was used by Lampizator in their 1st gen Atlantic, as well as in the XiAudio Sagra, so i think it’s safe to say that they are pretty great boards to work with. No idea how good is the implementaion done by Acuhorn though, never heard of them.

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Thanks for the great insight.

Don’t really understand the irony behind all the manufacturers.
The way I see it, you can buy everything there at Soekris and design it yourself.
Which is not bad at all.
I would have built one long ago if my knowledge of electrical engineering wasn’t terrible.
I think it’s bad that manufacturers buy in and do their own thing and sell it at 3 or 4 times the price and call it revolutionary, roughly speaking.

The circuit board may be somewhat limited, but as I have seen it, a lot can be done with the output stage, which is probably the secret of the whole thing.

Unfortunately I don’t know much about the Acuhorn stuff either.
But they have also made some interesting stuff.
With the Dam Board, a Pi or Amanero usb Board, as well as a tube amplification circuit, it can’t be all bad.

The R2R theme has become a bit tiresome, if you look around you can see some cool stuff.

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A majority of companies that use a Soekris board tend to HEAVILY modify parts of it for improvement. I can’t speak on Acuhorn, but I do know that the XI Sagra fits into that category and supposedly sounds nothing at all like a Soekris DAC.

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Actually looking at some photos you can see that some components on the Atlantic board are definitely not stock. Also as @Hazi59 said, inside the Sagra you can see that even more components have been swapped out in comparison to the Atlantic, although I couldn’t find any full photo of the latter’s board.

Users on diyadio also have done some mods to the board to improve it’s performance, so I would say that in terms of flexibility it seems to be a pretty great pick for a dac boad.

Now, looking at the Acuhorn, there doesn’t seem to be any modification made to the board. The components shape, size and color all look to be the same as the ones in a stock dam1121.
Maybe they did something but to an untrained eye like mine I couldn’t spot anything. If they did so they changed very few things but, again, I’m not an expert, so I can’t say for sure.

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