AnalogSteph
Major Contributor
Can a 2x2, 24/96 capable (UAC1) audio interface for a mere 65€ from Thomann's house brand be any good? Well, I just happened to need something to take care of an XLR condenser mic so I could finally liberate the Audient EVO 4 from my office PC and use it for portable measurements again, and I was curious about this model (the 102/108 dB ADC/DAC specs didn't ring a bell), so I placed an order...
First impressions: That's a chunky boi - the thick steel chassis makes this unit extraordinarily heavy and sturdy-feeling. (925 grams or literally just over 2 pounds - yowza!) The pushbuttons are a bit wobbly, but overall it feels like a solid piece of kit. The wood imitation side pieces are unsurprisingly plastic.
Sorry Dave, I did turn it on before taking it apart:
Both inputs including phantom power work fine with my t.bone SC400 LDC. HD600s get plenty loud enough on playback (and show no hiss there even with volume maxed), but mic monitoring could definitely use some more gain. Input noise level at minimum gain suggests a dynamic range of around CD spec. (Audacity's level meter says about -89/90 dB unwtd at 48 kHz and -92 dB A-wtd.) I have yet to test in loopback, silly me forgot to order some TRS cables and I may have to borrow my monitors' TRS --> XLR cables again.
The main monitor outputs have substantially more oomph than my ALC1200 onboard audio, even disregarding my speaker EQ and its pre-cut and a bit of Behringer HD400 insertion loss - I can really dig into the noise floor of dynamic classical recordings. Plugging the interface into USB generates a nasty spike on the main outputs, while unplugging creates a much less dramatic thump that is affected by monitor volume.
Prompted by my findings inside, I performed a dynamic mic test as well, digging out my 600 ohm Samson Q2U - I found it's usable but not the last word in input noise. I reckon my Mackie 402VLZ4 mixer (on ALC1200 line-in) is about 5 dB better, which does not bode well for more critical models like the notorious SM7B. EIN is likely to be about -120 dBu(A). At least it still sounds OK otherwise, not like e.g. the ESI Neva line which basically delivers telephone quality at high gain (no, I'm not kidding).
So what's inside?
After removing both side pieces, three more screws hold half the steel chassis in place, which slides off towards the front. The insides are a 2-layer construction with board to board pin type interconnects between two boards with all parts on just one side. There is a fair bit of open space on the bigger main PCB in particular,
So I start looking for the part that interests me the most, the audio codec. What do I see staring at me - a freaking Wolfson Micro logo. Sure enough, it's a trusty WM8776 codec (WM8776S / 05BSMEG). A common choice for soundcards in the mid-2000s, but I haven't seen one used in new gear in donkey's years. They were only discontinued by Cirrus Logic a few years ago though, last time buy was in summer of 2022. The DAC digital filter has a bit too much periodic ripple for my tastes, while the ADC is quite good for a consumer job. Dynamic range is better on the DAC side though.
The USB interface chip is a little square 48-pin thing hiding underneath a sticker saying "ESI018". Probably one of the things that were popular before XMOS took over the world. An 8-pin (T)SSOP job nearby is probably an EEPROM (ATH008 / 08CMPH / 2008QCF).
Between them is another SO-8 chip labeled 501MLF / 100205PY / 2117, no idea what that is (that's the most recent date code though).
There are a few JRC NJM4580 opamps dotted throughout the unit, looks like NJM4580Vs in SSOP-8. There are two next to the outputs alone, which suggests there is an actual balanced line driver circuit. That would certainly explain the powerful main output. Unfortunately it looks like 4580s with not much else around them are also used on the input side, it would certainly be consistent with mic input results. So file this one under "cheap audio interface good for condenser mics".
There is a little 12-pin MSOP (?) labeled SHY / TI 051 / CE12 which I presume is a headphone driver. Anyone got a clue what that is?
There is one prominent DC/DC converter inside the unit, presumably for +48V, with a 3- or 4-pin SOT23 labeled ?S52B. I very much assume the analog section is run on +5V single-supply, as par for the course in this class.
Next to the USB (type B) socket there is an SOT223, presumably an LDO (3.3 V?), labeled (logo) EH16A / 104TI2.
Armed with the WM8776S lead, I stumbled across this really quickly:
That's pretty much the little brother to our unit. The family resemblance inside and out is unmistakeable, mechanical construction seems quite similar. So I presume our USB chip underneath the telling "ESI018" sticker is also going to be a TE7022L, matching the general theme of "old faithful". The choice of sample rates (44.1, 48, 96 kHz - TE7022L doesn't do 88.2) would certainly support that, the Windows control panel software looks very similar as well.
vs.
(BTW, U22 XT pricing seems to generally have dropped to around 40€ now. Not a half-bad deal. Mind you, the Steinberg UR12 is being blown out for 44€ at this time, a CS4270 deal that makes decent use of this part. While still something that prefers condenser mics, that's more than just podcast grade already. Unbalanced output only though, even if converting that is not too much of a problem. Unbalanced circuitry on +/-5 V supplies internally, so half a step up from single supply jobs, especially on the input side.)
Speaking of software, version 2.0 installed on Windows 10 without a hitch and seems to be working fine. You can also download version 1.1 for older Windows versions which fixed some nasty bugs in the original 1.0 release (like bluescreens when unplugging). The driver files are bearing a copyright notice of (C) 2023 ESI Audiotechnik GmbH, further confirming the ESI connection.
During reassembly I lined the insides of the side pieces with Al foil in an effort to make the unit more RF-tight (not that I had noticed any issues, mind you, but it can't hurt; I didn't go so far as to be scraping off the paint where panels are touching). I don't think it had any issues before, but I certainly can't impress it with RF now (either 4G LTE or WiFi).
You will not be surprised to learn that the unit pretty much does not warm up at all in operation. Not a whole lot going on in there. It's not a Focusrite Forte for sure. I won't be surprised if it doesn't even draw 200 mA.
First impressions: That's a chunky boi - the thick steel chassis makes this unit extraordinarily heavy and sturdy-feeling. (925 grams or literally just over 2 pounds - yowza!) The pushbuttons are a bit wobbly, but overall it feels like a solid piece of kit. The wood imitation side pieces are unsurprisingly plastic.
Sorry Dave, I did turn it on before taking it apart:
Both inputs including phantom power work fine with my t.bone SC400 LDC. HD600s get plenty loud enough on playback (and show no hiss there even with volume maxed), but mic monitoring could definitely use some more gain. Input noise level at minimum gain suggests a dynamic range of around CD spec. (Audacity's level meter says about -89/90 dB unwtd at 48 kHz and -92 dB A-wtd.) I have yet to test in loopback, silly me forgot to order some TRS cables and I may have to borrow my monitors' TRS --> XLR cables again.
The main monitor outputs have substantially more oomph than my ALC1200 onboard audio, even disregarding my speaker EQ and its pre-cut and a bit of Behringer HD400 insertion loss - I can really dig into the noise floor of dynamic classical recordings. Plugging the interface into USB generates a nasty spike on the main outputs, while unplugging creates a much less dramatic thump that is affected by monitor volume.
Prompted by my findings inside, I performed a dynamic mic test as well, digging out my 600 ohm Samson Q2U - I found it's usable but not the last word in input noise. I reckon my Mackie 402VLZ4 mixer (on ALC1200 line-in) is about 5 dB better, which does not bode well for more critical models like the notorious SM7B. EIN is likely to be about -120 dBu(A). At least it still sounds OK otherwise, not like e.g. the ESI Neva line which basically delivers telephone quality at high gain (no, I'm not kidding).
So what's inside?
After removing both side pieces, three more screws hold half the steel chassis in place, which slides off towards the front. The insides are a 2-layer construction with board to board pin type interconnects between two boards with all parts on just one side. There is a fair bit of open space on the bigger main PCB in particular,
So I start looking for the part that interests me the most, the audio codec. What do I see staring at me - a freaking Wolfson Micro logo. Sure enough, it's a trusty WM8776 codec (WM8776S / 05BSMEG). A common choice for soundcards in the mid-2000s, but I haven't seen one used in new gear in donkey's years. They were only discontinued by Cirrus Logic a few years ago though, last time buy was in summer of 2022. The DAC digital filter has a bit too much periodic ripple for my tastes, while the ADC is quite good for a consumer job. Dynamic range is better on the DAC side though.
The USB interface chip is a little square 48-pin thing hiding underneath a sticker saying "ESI018". Probably one of the things that were popular before XMOS took over the world. An 8-pin (T)SSOP job nearby is probably an EEPROM (ATH008 / 08CMPH / 2008QCF).
Between them is another SO-8 chip labeled 501MLF / 100205PY / 2117, no idea what that is (that's the most recent date code though).
There are a few JRC NJM4580 opamps dotted throughout the unit, looks like NJM4580Vs in SSOP-8. There are two next to the outputs alone, which suggests there is an actual balanced line driver circuit. That would certainly explain the powerful main output. Unfortunately it looks like 4580s with not much else around them are also used on the input side, it would certainly be consistent with mic input results. So file this one under "cheap audio interface good for condenser mics".
There is a little 12-pin MSOP (?) labeled SHY / TI 051 / CE12 which I presume is a headphone driver. Anyone got a clue what that is?
There is one prominent DC/DC converter inside the unit, presumably for +48V, with a 3- or 4-pin SOT23 labeled ?S52B. I very much assume the analog section is run on +5V single-supply, as par for the course in this class.
Next to the USB (type B) socket there is an SOT223, presumably an LDO (3.3 V?), labeled (logo) EH16A / 104TI2.
Armed with the WM8776S lead, I stumbled across this really quickly:
That's pretty much the little brother to our unit. The family resemblance inside and out is unmistakeable, mechanical construction seems quite similar. So I presume our USB chip underneath the telling "ESI018" sticker is also going to be a TE7022L, matching the general theme of "old faithful". The choice of sample rates (44.1, 48, 96 kHz - TE7022L doesn't do 88.2) would certainly support that, the Windows control panel software looks very similar as well.
![cp.jpg](https://prosound.ixbt.com/interfaces/esi/u22xt/cp.jpg)
(BTW, U22 XT pricing seems to generally have dropped to around 40€ now. Not a half-bad deal. Mind you, the Steinberg UR12 is being blown out for 44€ at this time, a CS4270 deal that makes decent use of this part. While still something that prefers condenser mics, that's more than just podcast grade already. Unbalanced output only though, even if converting that is not too much of a problem. Unbalanced circuitry on +/-5 V supplies internally, so half a step up from single supply jobs, especially on the input side.)
Speaking of software, version 2.0 installed on Windows 10 without a hitch and seems to be working fine. You can also download version 1.1 for older Windows versions which fixed some nasty bugs in the original 1.0 release (like bluescreens when unplugging). The driver files are bearing a copyright notice of (C) 2023 ESI Audiotechnik GmbH, further confirming the ESI connection.
During reassembly I lined the insides of the side pieces with Al foil in an effort to make the unit more RF-tight (not that I had noticed any issues, mind you, but it can't hurt; I didn't go so far as to be scraping off the paint where panels are touching). I don't think it had any issues before, but I certainly can't impress it with RF now (either 4G LTE or WiFi).
You will not be surprised to learn that the unit pretty much does not warm up at all in operation. Not a whole lot going on in there. It's not a Focusrite Forte for sure. I won't be surprised if it doesn't even draw 200 mA.
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