Topping E2x2 Audio Interface Review

[Bob101]

I'm beginning to question whether these input gains aren't digital after all. I have plenty of evidence for the main line out and headphone volumes in their documentation, but haven't seen any for the input knobs, I just kind of assumed. Do we have evidence for these being analog?

The reason I got down this line of thinking is I was watching the Julian Krause review of it again yesterday and he shows in a graph that the input gain knob at 100% begins losing linearity roughly over 8k, but then shows it having nearly perfect linearity when the knob is around 75%. As we know there is a weird volume gain boost at around 80% which makes me wonder if it is activating some digital boost pad at that point.

I understand your comment is saying the software offers a digital boost above the highest gain of the knob, but I'm beginning to wonder if that digital boost is enabled by default and that maybe installing the software will allow me to disable it?

Having opened up the unit and examined it, and as far as my limited understanding of PCB circuitry goes, I can tell you this: the input gain knobs are analog pots. And pots control a VCA-circuit, integrated in or combined with the ADC-chip, which then translates the setting into a gain value.
However the input gain pots are of a dual layer layout. In short: instead of being a 'simple' variable resistor (like the main out, headphone out and monitor/input mix pots are) they are in a way two pots in one. They give two resistance values for every position. What those values are, their correlation, and most importantly what the ADC Chip is programmed to do with the combination of those values is anybody's guess but Topping's. It might well be the explanation for the non-linear behaviour of the inputs at and above certain gain levels mentioned before.
In this repect there is certainly room, and even a need, for improvement in future implemetations of Topping intefaces of this type.

 

[spankjam]

As I've mentioned, E1x2 seems to have seems to have a slightly better input DNR. And as staticV3 explained:

Just curious whether I have to get the OTG version to connect my phone and play back from it?

 

[Bob101]

Just curious whether I have to get the OTG version to connect my phone and play back from it?

I enable the outputs I want to use with my phone (line, HP or both) on the control center app and download the settings to device first (if you don't only the outputs selected in your last session will work). Then I disconnect the interface (power and usb-c) and only plug in my 5 year old Samsung (android version Ancient.2). It powers the interface, with signal to the output(s)s you selected. One thing: on my phone a rather large white mouse-pointer appears spot in the middle of the screen. I just ignore it and it does not move or interfere with phone operation. Mono signals are sent to left out only. When it works, it works, but when connecting my phone freezes like half the times. No big deal, just disconnect the phone. Then try again (a few tries tops). There might be a procedure where a certain sequence of device and phone powering up or down and connecting will always just work, but I haven't found it. Stopped looking for it, when I began to seriously doubt the actual existence of this mythical sequence. Both devices only agree to aknowledge they know what it is you want and grant you that wish after randomly plugging/unplugging and powering things up and down a few times. Takes ten seconds.
Those are my limited experiences. Never tried the inputs or monitoring with smartphone use. I wouldn't be surprised by some basic functionality. Or none at all.
Too cheap for a powerbank? Don't expect a smartphone battery by itself to feed hungry headphones for long before they start chewing your ears. (I'm looking at you there, Mr. ATH-R70x)
Your battery will get warm (older ones might overheat) due to the current draw. And a warm battery is only good for accelerated degradation and keeping your hand or a pocket warm. Conclusion: if you're looking for powerful, extra clunky, unergonmic portable headphone amp, and have big pockets, the Topping E2x2 should be on top of your list.

 

[SLAS]

Bob101​

Can you please tell me how clean Topping E2x2 plays, no noise? Maybe you have an oscilloscope to look at the outputs, and the headphone outputs. I want to buy Topping E2x2 and be satisfied with it. Need quality recording and playback. I bought a BEHRINGER UMC204HD, but returned it, can you see what noise on the output of the UMC204HD .

Behringer UMC204 HD Audio Interface Review

Use the inserts on the back and not the inputs on the front. The front inputs go through their special preamps (adding a bunch of distortion.) Using the inserts will bypass those preamps. Note the gain controls on the front will no longer function so you will need to manage the input gain some...

www.audiosciencereview.com

How many Topping E2x2's do you already have? how many percent out of 100% are you satisfied with it, can you recommend it as a quality and good product that you won't regret buying? Maybe there are some problems with it or something you don't like, let me know.

 

[SATB]

Having opened up the unit and examined it, and as far as my limited understanding of PCB circuitry goes, I can tell you this: the input gain knobs are analog pots. And pots control a VCA-circuit, integrated in or combined with the ADC-chip, which then translates the setting into a gain value.
However the input gain pots are of a dual layer layout. In short: instead of being a 'simple' variable resistor (like the main out, headphone out and monitor/input mix pots are) they are in a way two pots in one. They give two resistance values for every position. What those values are, their correlation, and most importantly what the ADC Chip is programmed to do with the combination of those values is anybody's guess but Topping's. It might well be the explanation for the non-linear behaviour of the inputs at and above certain gain levels mentioned before.
In this repect there is certainly room, and even a need, for improvement in future implemetations of Topping intefaces of this type.

Thank you for that analysis. I'm wondering if some mods will crop up over time.

I spent more time thinking about this yesterday while using it. I set to monitor mode on the input, which sends directly to the headphone out, and then recorded into a muted track in my DAW. I do believe that the speed of that send proves that we are receiving analog, since there is no lag of an ADC back into DAC.

And I also spent time turning the input knob while recording using an SM57 which is by far the most noisy experience possible, and the scratchy analog pots are clearly recorded mostly on that weird boost spot which is actually around 90% on my input knob. So, this interface is correctly and clearly recording what that analog input circuitry is sending to the headphones in monitor mode.

I have to wonder if this analog input circuitry could be modded somehow before it hits the adc with something more linear, and with more gain potential. On the other hand, maybe they committed to a very short throw length for the knob and this was a preferable analog knob compared to others.

I'm probably just dreaming though. I'm pretty much going to stick to using my phantom powered behringer c-2s which do amazingly at 75% on the knob for softer sounds and speaking. Going to hold back the SM57 for very loud sounds which is sad since I love its tonality on voice with the A2ws..

 

[Viper780]

Hi everyone,

I like to get low impedance Headphones (16-20 Ohm) and my current Interface can't drive them. Would it be a problem for the E2x2?

 

[staticV3]

Hi everyone,

I like to get low impedance Headphones (16-20 Ohm) and my current Interface can't drive them. Would it be a problem for the E2x2?

The E2x2 can drive low impedance headphones.

 

[Halcyon]

Those of you who bought and have used Topping Pro E2x2 or E1x2 series, can you comment on :

- stability and working of the hardware
- stability (bugs+) of the drivers / mixing software
- latency with mixing
- does it work ok with Windows games (both as a output soundcard and with mic inputs for chat)?

Still on the fence about this purchase. The Schiit Hel+ has been on back order for several months now (in EU) and many people have written that the QC on those units (previous batch) was less than ideal.

 

[kyuu]

Is AliExpress the only way to order one of these in the U.S.?

 

[SLAS]

kyuu​

I ordered from here, as the promo code is discounted right now.

https://vi.aliexpress.com/item/1005007295778890.html

 

[Halcyon]

E2x2 OTG is 199€ + shipping at Audiophonics France:

TOPPING PROFESSIONAL E2X2 OTG USB Audio Interface Black

Topping's E2x2 OTG is an excellent audio interface designed for musicians and audio professionals.

www.audiophonics.fr

 

[kyuu]

Hm, actually appears to be cheaper to order from France. In any case it's over $200 though. Wonder why Topping doesn't have any U.S. distributors.

 

[Grooved]

Hm, actually appears to be cheaper to order from France. In any case it's over $200 though. Wonder why Topping doesn't have any U.S. distributors.

Are you sure?
On AliExpress at this moment, it's $215 and you can use a code for -$20, so $195 and shipping is shown as free to USA

 

[Bob101]

Hm, actually appears to be cheaper to order from France. In any case it's over $200 though. Wonder why Topping doesn't have any U.S. distributors.

It is often cheaper (in EU) to buy Topping products from Audiophonics than from Aliexpress. Just bought a regular e2x2 from them for under 170€, shipping included.
On a sidenote: I greatly appreciated the option from Audiophonics to choose carriers other than UPS. They may cost a few € extra, maybe it takes a few days longer, but UPS have lost three of my packages in the last two months alone.

 

[PeterDLai]

Is AliExpress the only way to order one of these in the U.S.?

Amazon has them in stock sold by Toppingaudio now.

 

[mokiwoki]

Looking to buy a e2x2 otg. Instead of connect to PC and mobile, would it work with dual PCs?

 

[Bob101]

Looking to buy a e2x2 otg. Instead of connect to PC and mobile, would it work with dual PCs?

Interesting question. My guess (and anybody's until someone tries it) is that it will work. But likely with some, unpredictable, loss in functionality. Buy it, try it, send back if it doesn't work...

 

[Pauper]

Can this be powered from an iPad like my Arturia can

 

[AnalogSteph]

Can this be powered from an iPad like my Arturia can

5 V @ 0.8 A doesn't exactly suggest a power miser, and I wouldn't count on more than 500 mA from a mobile device. Even if it does work, I'd really want to have a USB powerbank to avoid draining the iPad's battery roughly twice as fast as normal. Ones with around 20000 mAh seem affordable enough and should give you roughly 16 hours or more of operation.

 

[Pauper]

5 V @ 0.8 A doesn't exactly suggest a power miser, and I wouldn't count on more than 500 mA from a mobile device. Even if it does work, I'd really want to have a USB powerbank to avoid draining the iPad's battery roughly twice as fast as normal. Ones with around 20000 mAh seem affordable enough and should give you roughly 16 hours or more of operation.

Thanks for the reply. It does look as if it needs assistance so it’s one to think about.