Topping E30 DAC Review

[fominator]

This is your 9th angry post about polarity reversal issue. I think you've made your position on the matter clear.

Perhaps now would be the time to find something constructive to contribute to the discussion,

I think it's more than constructive to inform buyers about it from Topping! Ok, here is my question! Does new fix actually fix the problem or not?

 

[Jarrett]

How common is reverse polarity on audio equipment? What if Amir tested and found it was as common as one-third?

 

[samsa]

How common is reverse polarity on audio equipment?

There are lots of speakers where the polarity of the drivers are reversed (say, the woofer in positive acoustic polarity and the tweeter in negative polarity). This is typically done to work around issues in the crossover region.

There are a fair number of amplifiers that reverse polarity (e.g., this one), to the extent that John Atkinson regularly made it a habit of stating in his measurements whether or not the amp being measured preserved polarity.

Dunno about DACs. There, a reversal of polarity seems more like an oversight than a design decision ...

 

[MondoAudio]

Thank goodness for the ignore button.

Thanks for this. I didn’t know this valuable tool existed.

 

[PeteL]

There are lots of speakers where the polarity of the drivers are reversed (say, the woofer in positive acoustic polarity and the tweeter in negative polarity). This is typically done to work around issues in the crossover region.

There are a fair number of amplifiers that reverse polarity (e.g., this one), to the extent that John Atkinson regularly made it a habit of stating in his measurements whether or not the amp being measured preserved polarity.

Dunno about DACs. There, a reversal of polarity seems more like an oversight than a design decision ...

Sorry Samsa but those are different things, If a speaker designer, to have phase coherence at crossover point have to compensate by flipping the polarity on a driver, that's a design decision and nothing is perfect when it comes to analog filter, bur there is a reason for it. There is absolutely no good reason to flip polarity at the output or a DAC or an amp, that's simply something that have been overlooked, not a design decision. A push should be a push and a pull should be a pull, many reported an audible difference in blind test, but even if you don't hear it, it's still wrong. Flaws in a system, when you take them one by one are not necessarely audible but flaws adds up, there is enough places when a signal can be degraded, and the thing is, it can be demonstrated that the negative portion of an audio signal is different than the negative portion, it is NOT symmetrical. OK maybe most don't hear it, but we want fidelity, and yes, maybe there will be other stuff that will mess with the phase and it won't be perfect, but It's not to much to ask to start with something that's right, il let my other analog equipment mess with the integrity of the signal. Amir here measure stuff that is simply not audible and yet, there are recommended components and other less so, that's not so much because the less impressive measurments sounds worst, but because we value good engineering decision and knowing that as a whole a full audio chain will have some flaws when accounting the some of the parts, knowing that what can be done right have been checked matters. Now it's really ok if it's not an issue for most, but the Dac part, I want to thnk of it as an instrument, that do what it has to do without behing the actor who decide what will be the push and what will be the pull.

 

[samsa]

If a speaker designer, to have phase coherence at crossover point have to compensate by flipping the polarity on a driver, that's a design decision and nothing is perfect when it comes to analog filter, bur there is a reason for it. There is absolutely no good reason to flip polarity at the output or a DAC or an amp, that's simply something that have been overlooked, not a design decision. A push should be a push and a pull should be a pull,

Whether or not there's a valid reason for it, if the tweeter's polarity is reversed, then "a push is not a push and a pull is not a pull."

I totally agree that there's no valid reason for a DAC to reverse polarity. But that wasn't @Jarrett's question. He asked how common it is for other audio equipment to flip polarity. And the answer is "fairly common."

P.S.:

There is absolutely no good reason to flip polarity at the output [of] an amp, that's simply something that have been overlooked, not a design decision.

There are various simple solid state amp designs which naturally invert polarity. (I'm too lazy to track down the G. Gordon Holt article which discusses this.) Unlike the case of a DAC (where flipping the polarity to be non-inverting is a couple of lines of firmware code), whether or not an amp inverts polarity is kinda baked into the design.

 

[yejun]

Whether or not there's a valid reason for it, if the tweeter's polarity is reversed, then "a push is not a push and a pull is not a pull."

I totally agree that there's no valid reason for a DAC to reverse polarity. But that wasn't @Jarrett's question. He asked how common it is for other audio equipment to flip polarity. And the answer is "fairly common."

I think high frequency is less affected by asymmetrical signal. Also for power amp it is very easy to fix by just reversing the speaker wiring.

 

[samsa]

I think high frequency is less affected by asymmetrical signal. Also for power amp it is very easy to fix by just reversing the speaker wiring.

For a DAC with balanced outputs (not the E30), the same is true.

 

[lex0rg]

Current stock of Aoshida Hifi got serial numbers starting with 2004xxx. I confirmed it today.
I guess we need a confirmation of TOPPING representatives on which batches/serial numbers the polarity fix was applied to ALL outputs from the factory.

 

[LeandroFlu]

Current stock of Aoshida Hifi got serial numbers starting with 2004xxx. I confirmed it today.
I guess we need a confirmation of TOPPING representatives on which batches/serial numbers the polarity fix was applied to ALL outputs from the factory.

Firmware description Version: V1.08 on its official website says

"This firmware is only for all E30 which SN number start with 1910 and 1911, and part of E30 which SN number start with 2003. The SN number could be found both at side of the box and the side of E30 body. "

soon we can assume that these are ...

 

[fominator]

i went through polarity test and the difference is so huge! it's not even funny to hear from @JohnYang1997 that it's not a problem and not an issue! i will open a case and send it back! and will never back to topping again, such incompetence

 

[timnkoo]

That was quite an entertaining review all-in-all and some informative parts...I'm not convinced by his subjective listening tests and his descriptions of the sonic effect of the different filters in terms of his listening experience, but that's the nature of subjective tests....I do think he was over-egging the significance of the filter . Having said that I have done something similar by going through the different filters in my G6 DAC and I did notice only a very subtle change, and I chose the one I liked best "Fast Roll Off, Linear Phase", so I can't discount his listening tests, but at the same time I can't put any weight on them....as he said though test them yourself and see which one you like best. I'm sure some people think that the filters don't have any discernible effect on the audible music.

This is the second review (subjective) that has highlighted "lifeless" results from the E30 when used in it's preamp mode when compared to DAC only mode. Are there ASR listeners that back this up (or counter arguement against it), or notice a difference when using it in DAC only mode with a separate "clean" preamp? As a buyer looking for my first DAC I was looking to utilise the preamp function for volume control straight into a power amp but now I've seen a couple of reviews mention the same thing I have my concerns...

 

[Koeitje]

i went through polarity test and the difference is so huge! it's not even funny to hear from @JohnYang1997 that it's not a problem and not an issue! i will open a case and send it back! and will never back to topping again, such incompetence

Can you show me a screenshot of your results?

 

[Toku]

i went through polarity test and the difference is so huge! it's not even funny to hear from @JohnYang1997 that it's not a problem and not an issue! i will open a case and send it back! and will never back to topping again, such incompetence

I want to know more about the results you got.
Please introduce the method you tested.

 

[fominator]

just listen to this test file with absolute polarity change

 

[tankas]

just listen to this test file with absolute polarity change

On this file I can easily hear the change. Someone with more knowlege, please let us know why. All this just doesn't add up.

 

[lex0rg]

Firmware description Version: V1.08 on its official website says

"This firmware is only for all E30 which SN number start with 1910 and 1911, and part of E30 which SN number start with 2003. The SN number could be found both at side of the box and the side of E30 body. "

soon we can assume that these are ...

Yes, I also hope that thats the case. That's the only thing that holds me back from buying it.
Can we plz get a confirmation from @JohnYang1997 or other TOPPING representatives?

 

[dpippel]

Audible or not, I'm going to get mine replaced as soon as Topping confirms that a fix has been implemented and provides a serial number range that identifies the corrected units. @JohnYang1997 ???? Please advise. Thank you.

 

[fominator]

i would replace it too, otherwise i will require full refund and check the seller for conscientiousness

 

[BDWoody]

i would replace it too, otherwise i will require full refund and check the seller for conscientiousness

You really need to relax...