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Topping E2x2 Audio Interface Review

Rate this audio interface

  • 1. Poor (headless panther)

    Votes: 10 3.7%
  • 2. Not terrible (postman panther)

    Votes: 25 9.3%
  • 3. Fine (happy panther)

    Votes: 131 48.9%
  • 4. Great (golfing panther)

    Votes: 102 38.1%

  • Total voters
    268
Also as an aside for those that think this is important. I noticed the new E2x2 OTG variant not the regular E2x2, has the ability to attach a mobile phone and PC at the same time.

I bought this audio interface for the off chance I could use it with my mobile phone and PC at the same time and route the channels for meetings where some people are on Microsoft Meeting and a remote person calls in to my mobile phone, where that person can hear the people in the STREAMED meeting and talk to them at the same time through my phone to the E2x2 OTG. It DOES! No more putting them on speaker phone and trying to get the headset close to my headset and speakers for them to join. This is also great for people who are gamers where a phone call comes in and he has to pick up, conferencing in late coworkers into meetings, and not having to take off your headphones when a call comes in. It also lets you record the call (legally please!), use the headphone amp and headset microphone for mobile calls. I use a Rode VXLR Pro 3.5mm to XLR adapter to my Sennheiser PC38X, with Phantom power and this is a keeper for me!

I'm hoping the next variant has optical input as well as output with 8 channel ADAT. I'm hoping their 8x8 has INPUT and output 8 channel adat as well to expand other audio interfaces.
What phone do you use?
For me, with Samsung S10e as well as a collegue's Samsung M30s, it doesn't work at all - no output when connecting with OTG port, and no input to phone regardless of normal or OTG port. With additional power, too.
See
Post in thread 'Motu M series with Android, anyone'

Contacted Topping because of that, let's wait what they say.
 
I have a Samsung Fold 5 on Android 14. It worked on the first go. Do you have the mixer setup properly? Used it for a meeting yesterday before I posted.
 
Here are my inputs. The one I sometimes miss is to increase the volume level in the MIX window. Please see the arrow in the image attached. If you don't want them to hear what you're listening to, in the Output, just choose Input 1.

arrow Screenshot 2025-01-08 135731.png
 
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What phone do you use?
For me, with Samsung S10e as well as a collegue's Samsung M30s, it doesn't work at all - no output when connecting with OTG port, and no input to phone regardless of normal or OTG port. With additional power, too.
See
Post in thread 'Motu M series with Android, anyone'

Contacted Topping because of that, let's wait what they say.
I have E2X2 OTG. To work with my Samsung S20 I need to connect phone to OTG port on topping, then restart topping(using switch on back panel) with connected phone. Then I see my phone in topping centre on computer and also otg indicator is on( device front panel). It also required additional power from usb charger.

There are "mobile applications" mode for regular usb port that you can switch using topping control centre on computer or by using instruction on screenshot below.
With regular usb port(not OTG) my Samsung S20 working in both modes, but maybe for some mobile devices it can help to work.

I also have iPhone 12Pro Max, and it's not working with any ports in any modes using usb-c lightning cable, but if I use lightning-usb adapter and then usb cable it's working with otg usb port. My lightning-usb adapter don't support additional power, but topping connected to power adapter.

1111.png
 
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I have E2X2 OTG. To work with my Samsung S20 I need to connect phone to OTG port on topping, then restart topping(using switch on back panel) with connected phone. Then I see my phone in topping centre on computer and also otg indicator is on( device front panel). It also required additional power from usb charger.

There are "mobile applications" mode for regular usb port that you can switch using topping control centre on computer or by using instruction on screenshot below.
With regular usb port(not OTG) my Samsung S20 working in both modes, but maybe for some mobile devices it can help to work.

I also have iPhone 12Pro Max, and it's not working with any ports in any modes using usb-c lightning cable, but if I use lightning-usb adapter and then usb cable it's working with otg usb port. My lightning-usb adapter don't support additional power, but topping connected to power adapter.

View attachment 419844
Interesting. I don't need to do any of that I just plugged in my phone. I swapped in my gf IPhone (don't know the model but it has usb c) and the iPhone gave me the option of using as a headset or other device (dac), then swapped back to my Samsung phone. I didn't toggle the power switch, just unconnected and plugged in the phone while the E2x2 OTG was on. The phone also asks if I want to give control to USB Audio Pro, or Moondrop Link. I'll see if Roon on my phone sees it as an additional output.
 
connect phone to OTG port on topping, then restart topping(using switch on back panel) with connected phone. Then I see my phone in topping centre on computer and also otg indicator is on( device front panel). It also required additional power from usb charger.
That's how I would had supposed it would work, too. But it doesn't with my S10.
The OTG indicator lights up, but neither is there any signal in the Control Center (mobile In) nor output LED meter on the device, and headphone/amp output stays quiet. I tried also the mentioned mobile mode, made no difference. (I have not understood, though, what that is supposed to do. When in mobile mode, Control Center is not working, but else?)

Vice versa, no signal from the microphones gets to the phone, in every possible combination I tried, what is no problem when connecting to PC instead.

To me, the E2x2 OTG simply is not Android compatible at all, except perhaps very recent Android versions. But that is not what product description says. I would just blame it on my 2023 Android (but honestly, less than 2 years! Android 12) if it wouldn't work without a glitch with the very simple Behringer UMC202 that was never advertised as 'Android compatible '. Plus, every Dac I owned (Audiolab M-Dac, Topping(!) E70, Tempotec Sonata Bhd) never had a problem taking the Samsungs output. So why the E2x2??
 
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Here the Control Center when phone is connected to device 'OTG input', power off & on again. Phone playing music to USB (says headphone is connected) but nothing to hear and see. Control Center should show 'Mobile input' and signal.
The OTG LED on the other hand, on device, lights up.
 

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Here the Control Center when phone is connected to device 'OTG input', power off & on again. Phone playing music to USB (says headphone is connected) but nothing to hear and see. Control Center should show 'Mobile input' and signal.
The OTG LED on the other hand, on device, lights up.
Yes, it is strange.
You can try to:
  • change the cable, sometimes it helps.
  • check if the latest firmware version installed on topping device and the last version of topping control centre also installed.
  • try to use another computer.
  • if you are using custom firmware on your mobile phone, there are may also be some changes in the behaviour of USB and sound in the phone settings under the developer settings.
 
Yes, it is strange.
You can try to:
  • change the cable, sometimes it helps.
  • check if the latest firmware version installed on topping device and the last version of topping control centre also installed.
  • try to use another computer.
  • if you are using custom firmware on your mobile phone, there are may also be some changes in the behaviour of USB and sound in the phone settings under the developer settings.
The cable is a good idea. Some cables are power only with no data. The Topping came with two cables, one going to my PC and another being used for power. I'm using a Astell and Kern cable that came with my SR35 to my phone. I believe the SR35 is Android 11 so I'll see if it works with that and also will try the Hiby R4. Lastly I'll try the Wiim Ultra, which would be amazing if it works, as it gives you more inputs, including digital inputs which this device is sorely lacking.
 
Ok here are my results. SR35 on stripped down Android 11 works.

1000015398.jpg


Hiby R4 doesn't work on Android 12 (maybe Android 12 is an issue?). Wiim Ultra is not recognized through USB. Roon on mobile app doesn't detect the Topping as a seperate out in the phone, but does of course see it on Windows 11 PC but doubles it, see photo below? (Maybe because it's connected to the phone as well?). Lastly tried to stream USB audio from my Shanling MC Mini CD player to it and sadly no. A USB audio input would have been very nice. But still very happy it works with my Samsung Fold 5 on Android 14. Makes it a 4 channel input dac for me with that function.

1000015399.jpg
 
Y'all made me curious if the e4x4 would work with my Android phone and yes it worked on the first try. Connected it via USB-C and that was it!

I'm using a Moto G32 with Android 13.

I was able to turn on the phantom power on 3 inputs before (I'm assuming) the phone shut down the interface for consuming too much power.
 
Just an update again as I learn to use this audio interface. The E2x2 multiple occurrences in Roon are the playback channels and they are all in WASAPI! Before I had my PC Roon app connected by Office PC Windows 11 Mixer, because it was the only way I could use Roon at the same time as playing other audio files such as Youtube. See, you can't use Wasapi of the Topping E50 at the same time as selecting it for your PC to use on Windows 11. Now I can use Windows as playback 1/2 and Roon for Wasapi playback on the other channels. The Topping Professional Control Center has opened up a lot of possibilities for me now and has been rock solid. LOL I've only had it for like 3 to 4 days, so I'll chime in if I run into problems with it.

I just WISH it had an optical (adat) and coaxial input as well. I mean I really don't understand how they missed that. With an optical (adat) people could get this and also the E4x4 as an expansion for 6 analog inputs later down the line. The lack of optical adat is in my opinion a mistake.
 
Just an update again as I learn to use this audio interface. The E2x2 multiple occurrences in Roon are the playback channels and they are all in WASAPI! Before I had my PC Roon app connected by Office PC Windows 11 Mixer, because it was the only way I could use Roon at the same time as playing other audio files such as Youtube. See, you can't use Wasapi of the Topping E50 at the same time as selecting it for your PC to use on Windows 11. Now I can use Windows as playback 1/2 and Roon for Wasapi playback on the other channels. The Topping Professional Control Center has opened up a lot of possibilities for me now and has been rock solid. LOL I've only had it for like 3 to 4 days, so I'll chime in if I run into problems with it.

I just WISH it had an optical (adat) and coaxial input as well. I mean I really don't understand how they missed that. With an optical (adat) people could get this and also the E4x4 as an expansion for 6 analog inputs later down the line. The lack of optical adat is in my opinion a mistake.
I don't think I know of any affordably priced 2 channel interface with ADAT or even SPDIF. You do get it as move up into more expensive gear or gear with more channels. I don't know if they just want to string the features out to higher priced gear or the market is so competitive where the E2x2 is that you cannot afford to add anything.
 
IIRC the E8x8 has ADAT.
 
IIRC the E8x8 has ADAT.
Unfortunately It has ADAT output but not input. My E2X2 OTG also has optical output, but it's not ADAT but SPDIF. I also think Toppings going to release a higher end interface with ADAT and if they push it, the same eq and DAC system as their D90 III discrete. But still at that point it would compete with the RME ADI-2 Pro FS and likely about the same price if it had analog inputs. Could you imagine a D90 III discrete converters audio interface, with ADAT for 8 additional inputs!

The more I think about it, the more it makes sense. If they made a D90 III discrete based interface with a dual ADAT and SPDIF inputs, we could use the E2x2 OTG or the E8x8 optical outputs and have D90 III discrete conversion capabilities! They could just leave out the preamp to keep costs down, letting existing users just use the D90 III based device as a convertor/interface, and also drive sales for the E2x2 OTG and E8x8 which have the preamps to optical out. This is getting exciting if they go this route! This coupled with being able to upload your custom peq to the discrete based convertor would be RME territory with their custom PEQ stored in box for in room eq.

(Edit: actually, thinking about this more, I don't think this would be optimal because without optical input on the E2x2 OTG and E8x8 they could only use their internal clocks. Edit 2: looking at the jitter by Amir, the E2x2 is very, very good though.)
 
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This is a review and detailed measurements of the Topping Professional E2x2 audio interface (ADC, DAC, Headphone Amp). It was sent to me by the company and costs US $159.
View attachment 322548
As the British would say, the E2x2 definitely "looks the part" as far as fitting in the general offering of interfaces in the market. And that extends to control app which seems a lot fancier than I expected from a company just getting into this market:
View attachment 322550
The company must have staffed up on the software side of things. You can power the unit exclusively via USB-C if your host supports its level of power (mine did), or with auxiliary USB-C power:
View attachment 322551

Note an interesting feature that if you use TRS in line In, you get a different gain than when using XLR. One is used for microphone and the other for line in/instrument.

We have three subsystems to test so let's get on with it.

Topping E2x2 DAC Measurements
Treating the unit strictly as a DAC, we have this for our dashboard:
View attachment 322552
I am so used to chart topping measurements from Topping DACs that this seems decisively less performant:
View attachment 322553
We do beat the spec so that is good.

Noise performance is better:
View attachment 322554
As is multitone:
View attachment 322555

Linearity is near perfect:
View attachment 322556

As is jitter:
View attachment 322557

IMD noise and distortion is along the same lines as the dashboard SINAD:
View attachment 322558

One filter is provided:
View attachment 322559

Wideband THD+N again is similar to what we saw in dashboard:
View attachment 322560

Topping E2x2 ADC Measurements
The E2x2 starts to show the strength of the brand in this department:
View attachment 322561
View attachment 322562

Noise performance is nice:
View attachment 322563

As is frequency response:
View attachment 322564

Measuring the IMD level was a bit tricky in that the gain impacted that initial hump. This measurement is also not ideal as it shows the generator level on X axis, not the output:

View attachment 322565

Still what is there seems pretty nice especially if you use the right gain structure. Testing against measured level, I had an older THD sweep which I resurrected:
View attachment 322566

As you see, it matched the reference pretty well.

Performance is essentially frequency independent:
View attachment 322567

Topping E2x2 Headphone Amplifier Measurement
Let's see if Topping brought its "A game" in this department:
View attachment 322568

Seems to be the case seeing how this is USB powered. Many competitors just have a checklist headphone amp with low power and high noise and distortion. Not here. We have good bit of power in high gain mode and excellent noise and distortion in low gain. Same is true of 32 ohm:
View attachment 322569

I was impressed by the noise level as represented in our 50 mv test:
View attachment 322570

Many stand-alone headphone amps struggle to achieve this level of quietness:
View attachment 322571

Conclusions
Topping gives us a "good" DAC in E2x2. But then surprises us with very good performance of its ADC and excellent response of the headphone amplifier. I suspect the cost constraints here kept it from delivering better DAC performance. For some reason I thought if Topping entered the interface market, they would top of the chart performance with costs to go with it. Thinking about it, they may have been wise to go after the entry level market first. This way, they pick up customers who are not wedded to long established brands.

I am impressed by the completeness of the product especially when considering the control app and such. You would think the company has been in market for many years.

I am going to recommend the Topping E2x2 audio interface as an entry level product.

E2x2 Specifications@24bits/96kitz)

1. Microphone Inputs:


Equivalent Input Noise@A-wt,150 Ohm | -130.5dBu
THD+N@A-wt | -110dB (0.0003%)
Dynamic Range @A-wt | 115dB
SNR | 115dB
Crosstalk@1kHz | -140dB
Frequency Response | 20Hz-40kHz (#0.2dB)
Maximum Input Level | 8.6dBu
Input Impedance | 1.5k Ohms
Available Gain | 58dB + 20dB (20dB digital gain)
Phantom Power | 48V
Phantom Power | XLR connector of the combo socket:

2. Line Inputs:

THD+N@A-wt | -107dB0.00045%)
Dynamic Range @A-wt | 115dB
SNR @A-wt | 115dB
Crosstalk@1kHz | -140dB
Frequency Response | 20Hz-40kHz (#0.1dB)
Maximum Input Level | 23.9dBu
Input Impedance | 6k Ohms
Available Gain | 58B + 20dB (20dB digital gain)
Connector Type | TRS connector of the combo socket:
Tip (Hot), Ring (Cold) & Sleeve (Shield)

3. Instrument Inputs:

THD+N@A-wt | -108dB (0.0004%)
Dynamic Range @A-wt | 115dB
SNR @A-wt | 115dB
Crosstalk@1kHz | -140dB
Frequency Response | 20Hz-40kHz (#0.3dB)
Maximum Input Level | 14.8dBu
Input Impedance | 1M Ohms
Available Gain | 58dB + 20dB (20dB digital gain)
Connector Type | TS connector of the combo socket:
Tip (Hot) & Sleeve (Shield)

4. Line Outputs:

THD+N@A-wt | -100dB (0.001%)
Dynamic Range @A-wt | 115dB
Analogue Dynamic Range@A-wt, -40B attenuation | 127dB
SNR @A-wt | 115dB
Crosstalk@1kHz | -128dB
Frequency Response | 20Hz-40kHz (#0.3dB)
Maximum Input Level | 14dBu
Noise @A-wt | 1.8uVrms
Output Impedance | 100 Ohms
Connector Type | 6.35mm TRS balanced jack:
Tip (Hot), Ring (Cold) & Sleeve (Shield)

5. Headphone Outputs:

THD+N @A-wt | -100dB (0.001%)
Dynamic Range @A-wt | 115dB
Analogue Dynamic Range @A-wt, -40dB attenuation | 132dB
SNR @A-wt | 115dB
Crosstalk@1kHz | -120dB
Frequency Response | 20Hz-40kHz (£0.3dB)
Maximum Input Level | OdBu@ Gain=L, 17dBu@ Gain=H
Noise @A-wt | 1 uVrms
Output Impedance | 1 Ohms
Connector Type | 6.35mm stereo headphone jack:
Tip(Left), Ring (Right) & Sleeve (Shield)
6.35mm stereo headphone jack | 580mWx2@320 THD+N<1%
380mW x 2@64Q THD+N<1%
198mW x 2 @1500 THD+N<1%
105mW x 2@3000 THD+N<1%
55mW x 2@6000 THD+N<1%

*Note: The above data is the result of the test in TOPPING laboratory.


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Looks like a clone of the MOTU M2. Amusingly, the DAC of the M2 is good and the ADC not so good. The Topping is the reverse.
 
Looks like a clone of the MOTU M2. Amusingly, the DAC of the M2 is good and the ADC not so good. The Topping is the reverse.
I don't know if it's looks like a clone, as the edges are sharp. Maybe the Black Lion if it were a bit wider. Was also dissappointed in the DAC performance measurements.
 
I think the MOTU looks better. The color screen and knurled knobs.
You probably could swap the knobs.

The lighter fluid bottle in the pic above looks ominous. Unless you are going to record a recreation of Hendrix at the 1967 Monterey Pop Festival.
 
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