On it's way, the AUNE Nano USB Dac

[PinkFloyd]

I was asked if I'd like to review the soon to be released Aune Nano USB DAC and I said "yes I would" so it's on it's way as we speak

I don't have much info on it, at the moment, but will give you the lowdown (including price) as soon as I get it, it should be with me in the next week or so.

Here are a few pics, in the meantime:

[Deleted]

Comparison against the NG27 should be interesting. Any technical differences of note? Pricing?

[FauDrei]

By the specs - average nobody among USB DACs/headamps. Nowhere near Aune mk2...

...might be wrong though... we'll see

[devilduck]

Priced the same as the superb Nuforce uDac, its going to be a tough sell.

[FauDrei]

I'm hearing about this nuforce thingie on many places... do you have a link or something?

[Deleted]

uDac site

[PinkFloyd]

I haven't got a clue what the "NANO USB DAC" is all about but Jeffrey wants to send me a sample so let's see how it pans out.

I will be trying it out of my laptop with relatively "low end" (but big hitters!) headphones such as PX-100, SR-60, KOSS portapro etc....

The NANO DAC, as far as I am aware, doesn't purport to being a "world beater".... I believe it's intended to be an "entry level" DAC for people with laptops etc.....

Not everything has to be "high end" , it's all about affordable musical reproduction equipment for all.....

Anyways, let's wait till it arrives and have a listen to it before discounting it as inferior.

(Remember...... quite a lot of people don't want to / can't spend huge sums of money on gear.... this forum is all about guiding them toward the best bang for the buck.... it is NOT about promoting the latest and greatest "cap fest" in a box ;D

[FauDrei]

Point taken.

[PinkFloyd]

The Aune Nano DAC arrived today. She is very well put together in a nice solid, curved aluminium enclosure with everything being a nice "tight" fit. It's not to the same quality of build as it's bigger brother, the Aune amp /DAC but still very impressive for the money.

It comes supplied with a 9V / 1000mA DC wallwart adaptor. To save me waffling on about components etc. I will just show you the pictures!














As you can see, it has been very well put together using good quality parts. Full description can be seen here en.hifidiy.net/DIY_Production/201001/t20100111_2294.htm

I had a quick listen via the Aune's headout and it was pretty mediocre with a slight degree of background noise "hiss".... perfectly ok for general listening to things like you-tube videos and other day to day computer "sounds" but not up to the standard I'd expect for listening to my favourite music.

I'm currently listening to it with the audio out hooked into one of My X-Can V2's



A definite improvement over the Aune's head-out but there is still a bit of background hiss (only really audible if you hit the pause button at LOUD volume levels).... it's not deadly silent like the AUNE Mini USB DAC + Headphone Amp.... let me stress, though, it's not really audible when music is playing (unless you've got hearing like a bat) it's only audible when you hit the pause button with the Volco notched up quite high. I'll see how it goes over the next couple of days and try a few different cables.

Sound quality is very good but not in the same league as the Aune Mini + amp (after 2 hours burn in) I will give it a week in circuit to settle in before comparing the two in more depth, it's never a good idea to reach instant conclusions, a lot can happen in a week

I've just disconnected the X-Can V2 and am back to the Aune's own head-out..... I've tried a few 'phones (KOSS portaPro, HD-250ll Linear, Superlux HD-681, Senn HD-25/1, Beyer DT-770) and there is definitely a degree of background noise..... not a lot but enough to warrant a mention....

Thing is, no point in me saying "this doesn't sound as good as a ££££ CD player"..... it's not purporting to be the best DAC in the world, it's there to serve a purpose in the "laptop" arena and probably with the "end users" listening through ipod buds.... I really don't know where to pitch my observations as I really don't have experience of "laptop as source" or listening through crappy "earbuds".

Maybe this is the best thing since sliced bread to some listeners and me comparing it to what I'm used to hearing is not fair.... it's good, it's bloody good but, so far into the listen, it's not something I could live with for long.....

As I say, just how / where do you pitch something like this?

I'll have a think

[Deleted]

As I say, just how / where do you pitch something like this?

The "Circular file "?
In the direction of someone with less impeccable tastes ?
Looks nice though.

[leo]

your limited with those all in one USB+Dac chips, they have everything crammed into the chip to serve a purpose, compact and cheap! still should be better than some laptop soundcards, the sound from the headphone out of my netbook is poor

[leo]

BTW, very odd choice of output transistors, those are low noise types but hardly suited for driving headphones

[elysion]

I have received the AUNE Nano USB DAC from Mike.

It works without problems with the OSX built-in drivers. I hear also the background hiss that Mike has mentioned.




The Nano DAC only runs with 9VDC wallwart. The device draws almost no bus power (20mA according to SystemProfiler) and can't run with bus power only.

I have compared it quickly with one of my Behringer UCA222's which is even cheaper than the Nano DAC. The Nano DAC uses the Burr-Brown PCM2707 while the UCA222 uses the PCM2902.

I have stated in the UCA222 thread that I don't hear any noise/hiss when I hit the pause button in iTunes while turning the pot to the maxium. I must correct this statement now: While comparing the UCA222 with the Nano DAC, I have noticed that there is a very slight background hiss that is hearable for not more than about two seconds after I have hitted the pause button. I'm rather sure the UCA222 stops the output totally after there's no input for about two seconds. Maybe some kind of hibernation, but perhaps this was an attempt of Behringer to cover the tracks...

Anyway, you won't notice any hiss with the UCA222 under normal conditions. As long as music is running it's also not noticeable with the Nano DAC.

IMO the Nano DAC has more details/resolution than the UCA222, but the UCA222 is still smoother and sweeter sounding than the Nano DAC. I'd prefer the UCA222 over all.

UCA222 is entirely bus-powered and draws 100mA from the USB bus. That's a good thing because usual USB ports can give a maximum of 500mA. You still have 400mA left on the USB port for other uses. Maybe I can improve the Nano DAC slightly with the use of an other wallwart, I'm already looking for a replacement.

I was a bit suprised that the Nano DAC doesn't run with bus-power, but perhaps the higher capacitance of its caps draws to much power. Otherwise I think both DACs have a lot of similarities.

I don't really like the USB port of the Nano DAC. The socket is somewhat to short IMO. USB cables that are plugged in are hanging a bit loose. The Native Instruments Audio 4 DJ audio interface has an USB port that gives a very good hold to cables plugged it. It's a different story with the UCA222: This one has a built-in USB cable whose wiring goes directly to the PCB. The UCA222 is also a lot smaller than the Nano DAC. IMO the UCA222 is much more suited for portable/notebook use than the Nano DAC. The Nano DAC has it's advantages – higher resolution and a different sound signature – but I think the UCA222 is clearly the better value.

I did a swap with Mike and got his Nano DAC cheap. Although the Nano DAC isn't really better than the UCA222 (and far away from the Behringer FCA202), it's still a welcome addition to my DAC armory. I hope to find a cure for the background hiss which is IMO one of two things that are slightly annoying. The second thing is the wallwart. The UCA222 and the FCA202 are running fine with bus-power only. I don't see a real reason why the Nano DAC must have a wallwart for operation. The UCA222 has caps with less capacitance, but the Nano DAC doesn't sound better at all. Given the lower price of the UCA222 (about half the price of the Nano DAC) the real advantage is minimal.

The Behringer UCA222 seems to be a rather good design that gets the maximum out of its cheap components. The FCA202 is quite similiar: Very good value for the price and quite appealing performance. I'm rather sure the FCA202 doesn't use the best available components too. But both Behringer's offer big-bang-for-small-buck.

If I could wish what should be changed with the AUNE Nano USB DAC, then it would be this:
– No built-in headphone out at all. I use it as DAC and not as headphone amplifier.
– Better USB connector.
– Powered by bus-power only.
– The switch would be almost senseless if the DAC would run with bus-power.
– A matt anodized finish. The shiny finish of the anodizing gives it a somehow cheap look. With some light conditions the shine looks almost in a mother-of-pearl style, almost a kind of paint that is slightly color-shifting. Beside the silver outlook the shine is kind of similar to cadmium treated surfaces.
– I don't need the coax SPDIF input. I could live without it, but it makes the it more universal. Maybe the SPDIF was one of the reason why the Nano DAC doesn't run without the wallwart. For SPDIF-only use no power is available over USB at all, here we need the wallwart as power source.

Overall the Nano DAC could be cheaper with the suggestions above. What about an USB-only DAC? For half the price but with better overall value?

[elysion]

DONE!

Arctic Silver Thermal Adhesive:




A bunch of heatsinks:




And a AUNE Nano USB DAC that got some heatsinks:













I can't comment about possible improvements at the moment.

I'd very suprised if there would be a big difference (if any). At least it should have no negative effect.

I've fitted the heatsinks because Alex suggested it for the opamps of the PreSonus HP4 amp. I decided also to fit heatsinks on the UCA222 and the AUNE Nano USB DAC. It will be interesting to see if there's any difference in SQ.

Feb 26, 2011 1:16:46 GMT @sandyk said:

The main problem is that the V-DAC uses a DIP-14 package while the HP4 has a MC33079 in SO-14 package (SMD).I found also some information about the SQ of the MC33079 and also a few suggestions for alternative opamps:

Something else to think about.
Based on quite a few people's experiences when replacing I.C.s such as the LM4562 DIP8 with a metal can version, ánd other reports about an improvement when some DIP8 dual opamps have mini adhesive heatsinks fitted, it seems possible that even though using the same chips internally, that the SOIC versions may not sound quite as good as their bigger DIP8 brothers due to running even hotter.
It could be interesting to fit a small adhesive heatsink to these quads, and see if you can hear an improvement.
N.B.
This is just a gut feeling.
Alex

Feb 26, 2011 3:01:00 GMT @sandyk said:

Do you think that this could have a relation with the opamps and too much heat

Christian
Most people who have tried the LM4562HA/LME49710HA dual metal can I.C.s agree that the metal can version sounds more refined,
and easier to listen to than the DIP8 plastic version. Still, most people feel the need to slip a heatsink on it, as it gets quite warm to the touch. Yet the DIP8 version has the same chip inside it, and must get damn hot internally.
I think the improvement may come down to better thermal management ? Is it a coincidence that some of the best sounding I.C.s also have very low distortion figures when correctly implemented.Yet according to dusty old textbooks, we are not supposed to be able to be aware of distortion at levels 100s of times higher, as long as they are below .01% !
Alex

[freddypipsqueek]

My experience is with late 90's, early 00's computers. To get them to run faster you would up the voltage (memory, CPU, FSB etc) . This created heat and so everything had a heat sink stuck to it and then a fan. You could get 30% improvement which at the time was £'s saved. At "stock" speed the heat sinks etc made them more stable. It also improved the life span of components; at the time things were moving so fast it didn't matter if kit failed after 2 years but now it does. My TDA1541 S2 chip now has a heat sink for this reason alone. I do wonder whether the question is not if the heat sink makes the kit sound better but if increasing the voltage can make it sound better; the heat sink allowing this to be done.

[elysion]

Did anyone notice that the AUNE Nano USB DAC has two blue turn trimmers mounted on the PCB – just like the Project Sunrise headphone amp.

I've had an important thought: Is it possible that these two turn trimmers are simply not correctly adjusted? I had the same problems as Mike (of course, it's the former DAC of Mike), but the bad performance is not typical for the AUNE gear. Perhaps simply a question of adjusting these turn trimmers... anyway, suggestions about this are highly appreciated.

I don't know where/what I should measure while turning the trimmers in other positions. Unless I know that, it seems not practicable to try. I don't want to damage something (especially connected amps and headphones).