Topping E30 DAC Review

[bogi]

Is there any difference in sound quality (even if it's only measurable) between PRE and DAC mode?

On 0dB none.

 

[pallatin]

On 0dB none.

That's the thing. Pure DAC mode is always 0 dB, but I need to control the volume to lower it to -6 dB. Would I lose sound quality that way in PRE mode?

 

[bogi]

pallatin, can you do it digitally on the digital source side? For example if you are playing from a software player, it has usually implemented higher precision digital volume control than DAC has.

 

[wasnotwasnotwas]

That's the thing. Pure DAC mode is always 0 dB, but I need to control the volume to lower it to -6 dB. Would I lose sound quality that way in PRE mode?

No. These days I wouldnt worry where in the chain you lose the 6db. If easier on the e30 with the remote, do that.

 

[eric00886]

No. These days I wouldnt worry where in the chain you lose the 6db. If easier on the e30 with the remote, do that.

Normally, "digital volume control" will decrease the quality of sound. I am not sure if E30 use digital volume control or analog volume control.

 

[infinitesymphony]

Normally, "digital volume control" will decrease the quality of sound. I am not sure if E30 use digital volume control or analog volume control.

This was talked about back around page 72 (link).

My understanding is that an analog passive attenuator like a JBL Nano Patch+ might preserve more SNR than the internal digital volume control, but the difference between the two in practice is so negligible it might not be audible.

 

[wasnotwasnotwas]

This was talked about back around page 72 (link).

My understanding is that an analog passive attenuator like a JBL Nano Patch+ might preserve more SNR than the internal digital volume control, but the difference between the two in practice is so negligible it might not be audible.

Exactly, yes digital volume truncates the bits, but what do people think is happening in the analog realm? And certainly not worth buying an extra box for.

 

[bogi]

You need to compare concrete implementations and use case. Every resistor in analog signal path adds its own noise.
If a listener doesn't hear any difference then it is not worth a discussion.

 

[ElNino]

Normally, "digital volume control" will decrease the quality of sound. I am not sure if E30 use digital volume control or analog volume control.

It uses the 32-bit digital volume control internal to the AK4493.

For Pallatin's application (i.e., just -6dB attenuation), there's no realistic unbalanced analog preamp that would outperform this implementation, for the reasons outlined here: https://confluence.merging.com/download/attachments/9338933/digital-vs-analog-volume-control.pdf

 

[Atanasi]

Is there any difference in sound quality (even if it's only measurable) between PRE and DAC mode?

Only if you use DSD. PRE mode converts to PCM in order to control volume. DAC mode is supposed to be native.

 

[wasnotwasnotwas]

Is there any difference in sound quality (even if it's only measurable) between PRE and DAC mode?

Not if you are at full volume in Pre mode and not trying to play native DSD. There is nothing added in the signal path in pre mode

 

[eric00886]

It uses the 32-bit digital volume control internal to the AK4493.

For Pallatin's application (i.e., just -6dB attenuation), there's no realistic unbalanced analog preamp that would outperform this implementation, for the reasons outlined here: https://confluence.merging.com/download/attachments/9338933/digital-vs-analog-volume-control.pdf

6dB is a huge number in audio:

1. SNR: 6dB can from Rank A to Rank B. In my project about PCM1794, we use OPA627 to replace NE5534 and only get 4 dB improvement in SNR.
2. Volume: 6dB is 4 times.

 

[eric00886]

You need to compare concrete implementations and use case. Every resistor in analog signal path adds its own noise.
If a listener doesn't hear any difference then it is not worth a discussion.

It will depend on device; speakers maybe much easier to separate than headphones

 

[wasnotwasnotwas]

6dB is a huge number in audio:

1. SNR: 6dB can from Rank A to Rank B. In my project about PCM1794, we use OPA627 to replace NE5534 and only get 4 dB improvement in SNR.
2. Volume: 6dB is 4 times.

So where would you suggest the poster loses 6db from the signal? I assume to lower signal into an amp, but I don't know.

 

[eric00886]

So where would you suggest the poster loses 6db from the signal? I assume to lower signal into an amp, but I don't know.

I will avoid to use digital volume control.

 

[ElNino]

6dB is a huge number in audio:

1. SNR: 6dB can from Rank A to Rank B. In my project about PCM1794, we use OPA627 to replace NE5534 and only get 4 dB improvement in SNR.
2. Volume: 6dB is 4 times.

So what? 6dB attenuation raises the noise floor of the E30 to roughly -134dB relative to the attenuated full scale. You can't better that with an unbalanced analog preamp.

 

[wasnotwasnotwas]

I will avoid to use digital volume control.

So youre suggesting another box in the signal chain (pre amp or otherwise) rather than the convenience of losing 6db in the dac or the software player? And the difference in those 2 implementations is audible?

 

[eric00886]

So what? 6dB attenuation raises the noise floor of the E30 to roughly -134dB relative to the attenuated full scale. You can't better that with an unbalanced analog preamp.

Is anything about unbalanced analog system?

You can do anything you like if you do not care about the lose from digital volume control. I will use headphone or preamp to control the volume in my system.

 

[eric00886]

So youre suggesting another box in the signal chain (pre amp or otherwise) rather than the convenience of losing 6db in the dac or the software player? And the difference in those 2 implementations is audible?

Sure. Will you connect speaker or earphone directly with E30? Normally, software player use digital volume control.

 

[Jose Hidalgo]

I think this has been discussed many times. This topic may also have been linked : https://hydrogenaud.io/index.php?topic=103887.0
AFAIK digital volume control can't decrease the quality of sound, as it remains bit-perfect... down to a certain degree of attenuation. And yes, it decreases the quality of sound beyond that degree. But what is that degree exactly ?

Players like foobar2000 handle data internally and of course losslessly in 32-bit.
So if your audio is 16-bit (like 99% of your audio should be), you have 16-bit of possible bit-perfect attenuation, which amounts to -96 dB.
And if your audio is 24-bit, you have 8-bit of possible bit-perfect attenuation, which amounts to -48 dB.
Most of the time you won't even go below -20/-30 dB. And if you did, it would probably not be for critical listening.

Bottom line : why would you even think of avoiding digital volume control ? Just don't sweat it.
I would use the player's digital volume control first, but you may prefer using the DAC's remote for convenience. Either way you won't feel a difference. It just can't be heard.