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Topping E30 DAC Review

Koeitje

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View attachment 58935

Noob question: Does all DAC use a worse chip for the optical input? I was always thinking usb and S/PDIF uses the same chip.
These are just the chips that take the spdif or usb signal and create something the DAC chip can use. Spdif and USB aren't the same, so you need a different chip for it.
 

Scriba

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These are just the chips that take the spdif or usb signal and create something the DAC chip can use. Spdif and USB aren't the same, so you need a different chip for it.

So with optical input I would still use the AKM AK4493 DAC chip?
 

AndyLu

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So with optical input I would still use the AKM AK4493 DAC chip?

Yes. All inputs go through the AKM4493 chip eventually, because that chip is the DAC chip. The other chips are only there to process the different inputs and send them to the DAC chip.
 

Scriba

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Yes. All inputs go through the AKM4493 chip eventually, because that chip is the DAC chip. The other chips are only there to process the different inputs and send them to the DAC chip.

Alright got it, thank you!
 

Koeitje

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So with optical input I would still use the AKM AK4493 DAC chip?
Yes, that other AKM chip is not a DAC its a SPDIF receiver chip that is also made by AKM.
 

Zek

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@Scriba
Input > SPDIF (optical/coaxial) > AK4118 > AK4493 > Output
Input > USB > XMOS > AK4493 > Output
 

MRC01

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...What chip companies call "sharp" is still soft in that instead of roll off at 22.05 kHz, it goes on to 24 kHz. That allows some energy to escape into ultrasonic frequencies as noted.
...
It looks like 24.1 kHz to be exact, and I doubt this is a coincidence because the numbers work out too perfectly, and I've seen it in other chips like the WM8741. It looks like it's taking advantage of the fact that aliases reflect around Nyquist. If the ideal passband goes up to 20 kHz, then a "correct" sharp filter should have full attenuation by 22,050 which leaves a very narrow transition band, only 2 kHz wide. Shifting the filter stopband higher to 24.1 kHz doubles the width of the transition band, making it easier to implement a transparent filter. And this puts Nyquist at the exact center of the transition band, so any frequencies above Nyquist that the filter allows to leak through, would have aliases above 20 khz (in the transition band, above the pass band). So any noise or aliases must be supersonic.

In short, it looks like a way to "stretch" the sharp filter to make it easier to implement transparently, while still guaranteeing that any noise is supersonic.
 
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yodog

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Welp I just received my E30 after receiving a DOA D50s. All I can say is, the E30 is pretty awesome and personally I think the screen on the E30 is much nicer and much more functional. The E30 doesn’t cause me sad fatigue like the DAC that’s within the Bluesound Node 2i.
 

MRC01

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In most cases, leave it in the "sharp" setting and forget about it. Plenty of more detailed technical discussions about this on this site, if you search.
 

yodog

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In most cases, leave it in the "sharp" setting and forget about it. Plenty of more detailed technical discussions about this on this site, if you search.

Sorry for not searching, but thanks for replying regardless. The sharp setting is the factory default setting yes? If so, I don’t need to change anything correct?
 

samsa

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The sharp setting is the factory default setting yes? If so, I don’t need to change anything correct?

Nope. The default setting is "Short Delay Sharp Rolloff" (#3), not "Sharp Rolloff" (#1). This is in the Manual.
 

MRC01

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Those filters (1 and 3) appear to have the same frequency response curve. I wonder what is the difference: passband ripple? phase / group delay?
And what exactly is the delay in #1, that was shortened in #3? Is it big enough to notice with video, as in audio out of sync with picture?
 

samsa

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Those filters (1 and 3) appear to have the same frequency response curve. I wonder what is the difference: passband ripple? phase / group delay?

I believe the difference is "linear phase" versus "minimum phase." Would have been nice if @amirm had published the impulse response for these filters.
 

MRC01

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If so, that could make sense. A minimum phase filter can have lower overall latency, tradeoff is non-flat phase and group delay vs. frequency. Too bad the manual doesn't give more info about this. But why would they make minimum phase the default? Usually, linear phase is more transparent and "correct" from an engineering & measurement perspective, and its total latency is not enough to cause any problem with video - audio sync.
 

Morpheus85

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I had ordered a D10 three weeks ago. This came now and I'm comparing both devices. The D10 really doesn't sound bad and has a slightly smaller stage. Which sounds better to me. My headphones have a large stage and the E30 makes them even larger, which is not particularly helpful when playing games. Now I don't know what to do. I paid € 65 for the D10 :eek:
 

sejarzo

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Nope. The default setting is "Short Delay Sharp Rolloff" (#3), not "Sharp Rolloff" (#1). This is in the Manual.

FWIW, BitDefender prevented that pdf from downloading on any of my Win10 machines until I clicked the "I understand the risk take me there anyway" option.
 

sejarzo

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I had ordered a D10 three weeks ago. This came now and I'm comparing both devices. The D10 really doesn't sound bad and has a slightly smaller stage. Which sounds better to me. My headphones have a large stage and the E30 makes them even larger, which is not particularly helpful when playing games. Now I don't know what to do. I paid € 65 for the D10 :eek:

I did the same thing when Drop put it on sale then nearly immediately the E30 came out. I do need the capability of an USB-to-SPDIF interface for a potential future project, so I think I will also sit tight with the D10 for now.
 

Jarrett

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I couldn't tell when I cycled through them. I have read though that sharp options measure best. The default #3, is a more modern sharp filter.

This is from AKM and applies to the AK4490. The AK4493 in the E30 has a sixth filter.

Linear phase Sharp Roll-off (AKMnotation: “no delay”): this is the “standard” sharp roll-off filter found isall DACs. It is also known as the “brickwall” filter. It is said thatpre-ringing sounds unnatural.

Linear phase Slow Roll-off (AKMnotation: “no delay”): this is also a “standard” filter found in all DACs. Asin the linear phase sharp roll-off filter, it also generates pre-ringing, buttrading lower amounts of pre-ringing with letting more aliased image through (theoretically increasing harmonic distortion).

Short delay Sharp Roll-off (AKM notation:“short delay”): this is also called the “minimum phase” or “apodizing” filterthat was the rage a few years back. Whereas in the past audio engineers have insisted in phase linearity (meaning all frequencies have equal phase ordelay), More recent research have shown that a “minimum phase” filter sacrifices some of the phase linearity (adds some phase distortion) for bettertime response. This filter removes all the “unnatural” pre-ringing but “dumps”all that energy to post-ringing. Implementation of this filter is also found inthe Wolfson WM8741/8742 DACs

Short delay Slow Roll-off (AKMnotation: “short delay”): this is a “more modern” type of filter also found inthe Wolfson WM8741/8742 DACs. In addition to eliminating pre-ringing, this filter also incorporates slow roll-off and this reduces post ringing as well.
The properties of this filter aresimilar to the "MP Filter" found in Ayres latest CD player.

Super Slow Roll-off: this filter is the differentiating feature (in terms of built-in filters) that this DAC provides. The AKM literature says “super slow roll-off filter with emphasized characteristics”(which really means nothing).
 
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