miniDSP U-DAC8 8-Channel USB DAC Review

[Tks]

So glad this thing was now also proven here to be a blunder. I recall seeing measurements elsewhere a few months back. Given the popularity, I couldn't believe it and thought maybe the tests done were iffy or something.

Now I got a question. How as no company created a device similar function to this, that just applies DSP to the signal without conversion to analogue, but instead requires a DAC to still do the processing. A sort of in-between the source, and DAC where the device is OS agnostic, and has on-board controls (or at least iOS/Android control)?

The sort of thing I am talking about is like the PowerDac V2, but on crack in terms of DSP capability. I imagine disregarding the need for a DAC chip would easily make the job less tough.

At least we can then avoid nonsense like this minidsp that neccesitates the signal go through conversion for amp duty after.

 

[ElNino]

Now I got a question. How as no company created a device similar function to this, that just applies DSP to the signal without conversion to analogue, but instead requires a DAC to still do the processing. A sort of in-between the source, and DAC where the device is OS agnostic, and has on-board controls (or at least iOS/Android control)?

I'm not sure if this is what you're asking, but the pro audio realm has a lot of multichannel interfaces like this, with onboard DSP that can operate entirely in the digital domain: MOTU CueMix FX and later devices, RME TotalMix, etc. (note, not all RME TotalMix devices have DSP, some just allow routing and digital volume adjustment).

If your computer can support Firewire somehow (either via an add-on card, the Thunderbolt adapter, etc.) and your OS hasn't killed many Firewire-only drivers (looking at you Catalina), some of the last generation of Firewire-only devices can be had at absurdly low prices on the used market these days, as studios unload them. For example, the MOTU 828mk3 firewire-only model offers six channels of digital output (for using external DACs), plus pretty decent analog performance on a whole bunch of analog outputs, the ability to control volume of multiple channels simultaneously via a single knob on the front in the digital domain, and a return channel in the digital domain where you can also insert your own host DSP if CueMix FX on its own isn't flexible enough in terms of DSP. I often see these going for around $200 these days. Newer devices often have direct control via an iOS/Android/web app, but you can also control these older units via OSC-enabled mobile apps like TouchOSC with a little configuration.

 

[Biblob]

I'm not sure if this is what you're asking, but the pro audio realm has a lot of multichannel interfaces like this, with onboard DSP that can operate entirely in the digital domain: MOTU CueMix FX and later devices, RME TotalMix, etc. (note, not all RME TotalMix devices have DSP, some just allow routing and digital volume adjustment).

If your computer can support Firewire somehow (either via an add-on card, the Thunderbolt adapter, etc.) and your OS hasn't killed many Firewire-only drivers (looking at you Catalina), some of the last generation of Firewire-only devices can be had at absurdly low prices on the used market these days, as studios unload them. For example, the MOTU 828mk3 firewire-only model offers six channels of digital output (for using external DACs), plus pretty decent analog performance on a whole bunch of analog outputs, the ability to control volume of multiple channels simultaneously via a single knob on the front in the digital domain, and a return channel in the digital domain where you can also insert your own host DSP if CueMix FX on its own isn't flexible enough in terms of DSP. I often see these going for around $200 these days. Newer devices often have direct control via an iOS/Android/web app, but you can also control these older units via OSC-enabled mobile apps like TouchOSC with a little configuration.

I am unfamiliar with FireWire. Are there any adapters, converters available to make it backwards compatible with USB?

 

[ElNino]

I am unfamiliar with FireWire. Are there any adapters, converters available to make it backwards compatible with USB?

Sadly, no; the protocols are very different. There is an inexpensive adapter that allows use of Firewire devices on computers with Thunderbolt ports, and if you have a desktop machine you can still buy add-on Firewire PCI cards. The lack of compatibility with modern ports is part of what's driving studios to unload this type of gear when they upgrade.

 

[yummy]

minidsp is a hong kong company, trying to fake to a US one

 

[somebodyelse]

Now I got a question. How as no company created a device similar function to this, that just applies DSP to the signal without conversion to analogue, but instead requires a DAC to still do the processing. A sort of in-between the source, and DAC where the device is OS agnostic, and has on-board controls (or at least iOS/Android control)?

Something like the nanoDIGI perhaps? Most of the others I know of have i2s rather than spdif.

 

[digitalfrost]

Now I got a question. How as no company created a device similar function to this, that just applies DSP to the signal without conversion to analogue, but instead requires a DAC to still do the processing. A sort of in-between the source, and DAC where the device is OS agnostic, and has on-board controls (or at least iOS/Android control)?

I don't think there exists an easy to use device. In principle, any computer with digital inputs could be used for this - but then it would probably be easier to use the PC as playback device. You could built something like this with a proper soundcard and a cheap PC (or Raspberry) and BruteFIR. Or use Windows and Acourate.

 

[Deleted member 2944]

minidsp is a hong kong company, trying to fake to a US one

 

[Nick Laslett]

So glad this thing was now also proven here to be a blunder. I recall seeing measurements elsewhere a few months back. Given the popularity, I couldn't believe it and thought maybe the tests done were iffy or something.

Now I got a question. How as no company created a device similar function to this, that just applies DSP to the signal without conversion to analogue, but instead requires a DAC to still do the processing. A sort of in-between the source, and DAC where the device is OS agnostic, and has on-board controls (or at least iOS/Android control)?

The sort of thing I am talking about is like the PowerDac V2, but on crack in terms of DSP capability. I imagine disregarding the need for a DAC chip would easily make the job less tough.

At least we can then avoid nonsense like this minidsp that neccesitates the signal go through conversion for amp duty after.

Not quite the same thing, but I use two NanoAVRs for Bass Management and Dirac. This uses HDMI, so not suitable for most people‘s setups.

I just hope that because in the NanoAVR the signal is all digital and uses 32 bit floating point, that the output is bit perfect, if no DSP is applied. The Kal Rubinson article on the miniDSP U-DIO8 indicated that it was bit perfect.

https://www.stereophile.com/content/music-round-93-minidsp-ripping-sacds

 

[ElNino]

I just hope that because in the NanoAVR the signal is all digital and uses 32 bit floating point, that the output is bit perfect, if no DSP is applied.

The NanoAVR always uses asynchronous sample rate conversion, so it won't be bit-perfect even with no DSP (if you're defining bit-perfect as the same bits coming out as going in). Even if you feed it a 96kHz signal the bits will change because the sender and receiver's clocks can't be perfectly in sync. That's not a design flaw though; it's the most natural way to handle clocking for this type of device.

 

[Nick Laslett]

The NanoAVR always uses asynchronous sample rate conversion, so it won't be bit-perfect even with no DSP (if you're defining bit-perfect as the same bits coming out as going in). Even if you feed it a 96kHz signal the bits will change because the sender and receiver's clocks can't be perfectly in sync. That's not a design flaw though; it's the most natural way to handle clocking for this type of device.

Thank you. You have explained that very well. The challenge created with ASR reviews, is you begin to question the implementation of many things you originally took for granted with audio equipment.

 

[pos]

Thanks for the review @amirm !
The measurements are not far from the published specs, no surprise there.

I can confirm the UDIO8 (digital in/out version) works very well.
I cannot measure the jitter it produces, but whatever it is a good DAC should be able to handle it.
I would still be curious to see it thoroughly measured though...

 

[Labjr]

I'm still waiting for a reasonably priced 8-channel DAC with DSP that's capable of being used as a stereo 4-way crossover, that outperforms an analog active crossover.

 

[Tks]

I'm not sure if this is what you're asking, but the pro audio realm has a lot of multichannel interfaces like this, with onboard DSP that can operate entirely in the digital domain: MOTU CueMix FX and later devices, RME TotalMix, etc. (note, not all RME TotalMix devices have DSP, some just allow routing and digital volume adjustment).

If your computer can support Firewire somehow (either via an add-on card, the Thunderbolt adapter, etc.) and your OS hasn't killed many Firewire-only drivers (looking at you Catalina), some of the last generation of Firewire-only devices can be had at absurdly low prices on the used market these days, as studios unload them. For example, the MOTU 828mk3 firewire-only model offers six channels of digital output (for using external DACs), plus pretty decent analog performance on a whole bunch of analog outputs, the ability to control volume of multiple channels simultaneously via a single knob on the front in the digital domain, and a return channel in the digital domain where you can also insert your own host DSP if CueMix FX on its own isn't flexible enough in terms of DSP. I often see these going for around $200 these days. Newer devices often have direct control via an iOS/Android/web app, but you can also control these older units via OSC-enabled mobile apps like TouchOSC with a little configuration.

Obviously there are professional devices. What I was inquiring about is a simple consumer level device with potentially full control in and out of the dedicated hardware. Also Firewire, that instantly disqualifies those devices as something simple for basic things like EQ, Loudness, perhaps also custom proprietary filter effects (like the sort of stuff you see in virtulization of "3D" sound as found with much gaming audio software) basic things of that nature.. Likewise the size of these devices, I don't need something larger than my DAC or amp for example, I am talking something potentially portable in your pocket like a smartphone.

 

[JoachimStrobel]

Some of the miniDSP products now are a bit long in the tooth. They really need to be updated. The nanoAVR HDA, for example, only has HDMI 1.4a inputs and output. I can't see myself thinking of buying it now. I almost bought the U-DAC8 two months ago, but was rather disatisfied with the lack of any other input, e.g. SPDIF.

I have a NanoAVR HDA (with Dirac). I compared to the Oppo 103 and Parasound Dac2000. While the Oppo is known to be not that good, the 105/205 versions are better but roughly 10x the price now, the Parasound is regarded a top DAC, being a bit soft and LP like coming from a different age.
Now, the HDA was almost identical to the Oppo, sitting at its HDMI end fed with LPCM ( what else). Converting the HDA‘s HDMI output to Coax feeding into my Parasound took three HDMI extractors boxes bring send back before I found a good one. Anyway, the Parasound beats the HDA for sure for 2channels, but given the price tag for such an increase in fidelity makes me hesitate to condemn the HDA.
But the HDA-DL is all bout Dirac, and once audio gets passed through and messed up by the Dirac treatment, the quality of the DA seems secondary.

 

[ernestcarl]

I have a NanoAVR HDA (with Dirac). I compared to the Oppo 103 and Parasound Dac2000. While the Oppo is known to be not that good, the 105/205 versions are better but roughly 10x the price now, the Parasound is regarded a top DAC, being a bit soft and LP like coming from a different age.
Now, the HDA was almost identical to the Oppo, sitting at its HDMI end fed with LPCM ( what else). Converting the HDA‘s HDMI output to Coax feeding into my Parasound took three HDMI extractors boxes bring send back before I found a good one. Anyway, the Parasound beats the HDA for sure for 2channels, but given the price tag for such an increase in fidelity makes me hesitate to condemn the HDA.
But the HDA-DL is all bout Dirac, and once audio gets passed through and messed up by the Dirac treatment, the quality of the DA seems secondary.

Thanks for sharing! I do think the HDA is still quite remarkable in what it can do for the price. And I’m not exactly a SINAD score obsessor like many. As I stated, it’s the older HDMI standard mainly that’s my major annoyance. Dirac is also not a necessity to me, as I would still prefer to do things manually. At the very least I want 4k with 60Hz to work. To me, video is just as important as audio. If they have to add another $100 to its price, that’s fine with me so long as they bring its HDMI inputs and outputs up to current spec. Seriously, HDMI 1.4a is hella old.

 

[JoachimStrobel]

Most BD Players have two HDMI Outputs, where one is optimized for LPCM-Audio as it does not care for so many Video frequency where Audio is interlaced and hence has a more stable clock. Those outputs are HDMI 1.4 which seems to be enough for all Audio stuff. The problem occurs with the Apple and Amazon 4k boxes that have only one HDMI output. There are boxes around that break HDMI 1.4 out of that HDMI 2.x stream but am not sure how good they are.

I attach my 4k Apple TV directly to my projector (near the projector so I avoid long HDMI cable issues too) and stream the music to an old Apple tv box that is linked to my Oppo 103. Good enough for Video for me and I am still saving for an Oppo 203.

 

[mjwin]

Hi Amir & folks at ASR. I came across this site only a few weeks ago & have since spent a bit of time looking through a few threads. It's good to see that some sanity still exists amidst the nonsensical, meaningless banter that surrounds home audio these days. So keep up the good work, guys!

I just wanted to chime in here to say that I purchased a UDAC8 a couple of months ago having failed to find any other simple multi-channel DAC which was truly USB audio class 2 compliant.

I, too, had hoped that the UDAC 8 would be a straight forward, functional device with decent performance. By this, I was expecting a measured performance in the same ballpark as the Focusrite Scarlett (or Tascam US2x2 which I currently use). Nothing state of the art, but adequate. Apart from the requirement that the device be class compliant, and compatible with Linux, I really needed a unit with variable, balanced outputs, but was prepared to work around this for the sake of meeting my immediate needs (experimenting with multi-channel soundscape playback).

Having tested for basic functionality, I just thought I'd run some tests using my Tascam box as a signal source. I was expecting very similar performance, but oh dear... My measurements are actually very close to yours - Full scale THD 0.014% with slight differences in 2nd & 3rd harmonics, but generally much the same - which at the very least indicates that yours was not a rogue unit. But it's strange that the measurements are that much worse than the AK4440 spec would suggest, especially given that the outputs use the internal chip buffers and are pretty much as per the datasheet.

For me, it's not worth worrying about the measurements right now as I guess this unit will serve for my current purposes. In any case it falls short in terms of required functionality for longer term use. Thanks to ASR I now have my eye on an Okto DAC8 - If that box ever makes it to full production, with its exemplary standard of construction & measurements to match, it will be such amazing value compared to this MiniDSP offering which itself wasn't exactly cheap, & still cost me around EUR350!

 

[Nathan Raymond]

Ah, yes, Sound Blaster... who could forget the brand? I had a much older sound blaster (5.1) external card like the one you reviewed. RCA outputs were acceptable on that one. HP output was garbage, though! The worst HP out I've heard in my life -- maybe a manufacturing defect -- who knows. That was the only DAC & HP amp combo I ever threw out in the the trash bin. Hmmm. On second thought, maybe I should've just donated it to some second-hand thrift shop. That was maybe over ten years ago so... eh, never mind.

Creative has been progressively improving their headphone amplifiers in the products, especially their mid and higher end ones, over the last 10 years and they are pretty respectable now, capable of driving 600 Ohm headphones. I'd like to see how their flagship SoundBlaster AE-9 performs on the bench though - it has an ESS Sabre 9038 DAC and Creative claims 129 db DNR and 0.0001% THD. They make other claims about engineering it to be isolated from power interfere on other voltage rails in the computer too.

On a side note, Creative has also gotten in the habit of exposing the op-amp sockets on cards like the AE-9 to make it easier for end users to swap, and so people are dropping even more money on discreet op-amps from companies like Burson and SparkoS... would be interesting to see if such things actually make an objective improvement.

 

[avm]

I almost bought this DAC some months ago thinking that it would be a massive improvement over the on-board Realtek DAC of my computer. What a disappointment. Having already seen some measurements and some posts on integrated audio codecs I am quite astonished that this chips are really quite good for what they cost. I'm glad I saved myself some good hundreds of dollars for an underachieving and ridiculously overpriced DAC.