Topping E50 Review (Balanced DAC)

[BKDad]

Both look like they'd do the "job".

Well, maybe.

Imagine that you saw a review of a sports car from a very reputable tester. The car was great in every way. In addition, it was an absolute bargain. The tester found that the car could get to 100km/hr in 4.0 seconds, which isn't in the 3 second range of the really expensive guys, but for the price it's still magnificent.

So, you buy one with the intent of converting it to a race car in the appropriate category. Your first step is to test the car to get a baseline of where you're starting from.

You discover that no matter what you do, the fastest it will do 0-100km/hr is 4.8 seconds. This wouldn't matter for your ride to work, to the beach, or to the grocery store. But, it might not be so competitive as a race car.

Now, do you have a bad sample? Is something misaligned? Is it fixable? Was the sample provided to the tester a "ringer" and not representative of actual production units?

These are my questions.

I'm not suggesting that anything is underhanded or corrupt here. I just think that there may be something wrong with my unit. OK, maybe not wrong, but not optimized. Since both channels test pretty much the same, it doesn't seem likely to be a bad DAC chip or opamp. Besides, the noise performance is really great. Here, the 2nd and 3rd harmonics are worse than in the D10s sample I own. That doesn't seem right.

I know that ESS DAC chips use distortion compensation that can be tweaked and saved in the firmware associated with the chip. At least one manufacturer provides a means to do that at home. I'm hoping that Topping has something similar, or that somebody has figured out how to do it unofficially.

 

[Rantapossu]

Primarily, the 3rd harmonic of the 1000 Hz tone is much higher than what he published. Mine is about 10 dB worse; around -123 dBc under the same conditions as Amir tested. The other harmonics measure very close to his results. Same for the noise level.

Have you tried to play with both channels? You can activate the second channel with the "Timing Reference Output" setting:

The output doesn't have to be connected to anything, but for me it makes the 3rd harmonic to go -15 dB (or so) down if I play with the both channels simultaneously...

And please use the notch when testing so the results would be comparable to tests of the other users.

 

[Rantapossu]

If I can't I'll probably give the DAC away and stick with the D10s. It's got worse noise, but the distortion is better.

If you too can fix the 3rd harmonic with playing both channels simultaneously, E50 will eat D10s for breakfast. Both channels playing, AES-17 -notch active in REW and E50 connected to APU with the balanced output, -120 dB THD+N easily...

 

[BKDad]

Have you tried to play with both channels? You can activate the second channel with the "Timing Reference Output" setting:

View attachment 319183

The output doesn't have to be connected to anything, but for me it makes the 3rd harmonic to go -15 dB (or so) down if I play with the both channels simultaneously...

And please use the notch when testing so the results would be comparable to tests of the other users.

Thank you for the suggestion. I'd never considered that! But, unfortunately that had no effect.

Here's the plot you requested:

.
Easy to see the problem.

I'd buy another E50, for all the reasons you mention, if I thought the next one was any better.

 

[Rantapossu]

Thank you for the suggestion. I'd never considered that! But, unfortunately that had no effect.

Sorry, I said it wrong, it still plays with only one channel with Timing Reference Output selected...

Please try this to enable the second channel:

This is my H3 with and without the second channel playing with a cold unit:

-119,7 dB left channel only playing
-134,7 dB both channels playing

 

[BKDad]

Well, that is amazing!! How did you discover this? And, why does it work this way?

I knew somebody here would have an answer. THANKS!

 

[Rantapossu]

Well, that is amazing!!

Yes, it is...

How did you discover this?

Hundreds of hours of beta testing @pkane 's Multitone have tought me something...

Multitone plays with the both channels as a default when newly installed. There was too big difference with REW when considering H3 and many use REW with only one channel, like I did. Activating the second channel brought it in line with Multitone and the second channel has been turned on since. There's the same 15 dB penalty of H3 with Multitone too if I shut the second channel.

And, why does it work this way?

I have no idea, it just does it.

I knew somebody here would have an answer. THANKS!

No problem!

 

[BKDad]

Yes, it is...



Hundreds of hours of beta testing @pkane 's Multitone have tought me something...

Multitone plays with the both channels as a default when newly installed. There was too big difference with REW when considering H3 and many use REW with only one channel, like I did. Activating the second channel brought it in line with Multitone and the second channel has been turned on since. There's the same 15 dB penalty of H3 with Multitone too if I shut the second channel.



I have no idea, it just does it.



No problem!

Two things.

I tried the Invert Second Output option in the same generator panel.

This gives further improvement in the 2nd harmonic and eliminates some higher even order harmonics.

I then tried the two changes with a D10s:

Same effect for the 3rd harmonic, although not as much, as well as some other improvements.

This is L+R with and without Invert Second Output clicked:

More even order improvements.

These are not relevant to actual listening, but are for testing.

Thank you again!

 

[BKDad]

I have no idea, it just does it.

Forgot! Since the effect is the same in two very different software applications, that suggests that this is a thing within the DAC, right?

 

[Rantapossu]

Please note that the temperature of E50 and APU does affect the results too. H2 will most likely drop even if you don't do anything else than wait...

 

[Rantapossu]

that this is a thing within the DAC, right?

Yes. But no one other than ASR members play the DAC just on one channel with 0 dBFS sine wave, so it doesn't matter in real life...

 

[BKDad]

Please note that the temperature of E50 and APU does affect the results too. H2 will most likely drop even if you don't do anything else than wait...

They were both powered for more than one hour. But, yes I've observed that as well.

 

[BKDad]

Friendly question, are you using the E50 just as a science experiment or for use in an audio playback system?

I wouldn't call it a science experiment, really, but I've never connected it to an audio playback system. It is used entirely for testing analog stuff like preamps and amps as I develop them.

So, I guess it is a science experiment.

 

[poptopclk]

There will be current flowing through at the same time. But they are not joined together shorting each other. L50 has relay switches for input selection and the toggle switch is at the front.

Yes, you can. That's what people been doing for a long time. And I also recommend splitting balanced output to two for both sub and the mains if your sub takes balanced signal. More usual case /more sensible to me is to feed the main from the sub's pass through. It's pretty flexible.

I like this, has anyone done this? It would be great if I can use the RCA outs to my monoblocks & the pair of balanced to my SUB (you need BOTH channels for all the bass right?) However, my sub has only 1 XLR input but 2 RCA & 2 Line level inputs & LFE (RCA) so HOW, would I do this ?

 

[poptopclk]

Would this work? A pair of TRS male to XLR male mated to XLR3 male to Dual XLR3 female Y Cable and plug the single male lead to the SUB ?

 

[poptopclk]

I've used the E50 in a near field setup this way.

1. TRS out E50 to XLR in Emotiva XPA-2 Gen 2 power amp
2. RCA left out E50 to RCA left in (low level) SVS PB12 sub #1
3. RCA right out E50 to RCA right in (low level) SVS PB12 sub #2

Then set the low level pass frequency and gain to desired level. With near field it's been easy for me to achieve excellent integration between the mains and subs. Some will argue it's dangerous to run the DAC directly to the amps, but that's a whole other discussion. I usually turn the DAC on, before the amps, and run the digital volume control down low before turning the amps on.

It will work with any DAC that has the ability output RCA and XLR simultaneously like some Topping DAC's do.

My Emotiva Amps have only RCA so that won't work for me. Would the cables I show combine the stereo (mini XLR i.e. TRS) to mono for the SUB Female single XLR input?

 

[Rantapossu]

Would the cables I show combine the stereo (mini XLR i.e. TRS) to mono for the SUB Female single XLR input?

They will combine the stereo signal to mono, but you dont't want to do it that way, it might kill your E50. Short circuiting the left out and right outputs together without the summing resistors is a big no-no.

 

[poptopclk]

Thank you for that information ! In further research, I found a website that claims to fix this issue. Would this cable resolve my dilemma?

 

[Rantapossu]

Thank you for that information ! In further research, I found a website that claims to fix this issue. Would this cable resolve my dilemma?
View attachment 320155

Hard to say without knowing the specs. In theory, yes.

 

[poptopclk]

This Topping E50 sounds amazing as a pre-amp for a Wiim Pro optical input into a pair of monoblock amps. I'm hearing what seems like 10% more of the source material's details. An example, I was listening to Steely Dan's album, Aja, "Black Cow" all these years I thought it said; Was a Bogart Novel, in the lyrics, with this DAC I got "Was a book of numbers" Ok, I hear what I was missing....