Khadas Tone2 Pro Review (DAC & Amp)

[solderdude]

Of course the upsampler could also be better. The problem for the average Joe is that they generally have no way of knowing unless they know what to look for.

The 22kHz filtering (full attenuation at 24kHz) is not as technically 'perfect' but it doesn't have to be in practice using music.

Blu-ray:
LPCM (Lossless) 48 kHz, 96 kHz, 192 kHz
Dolby Digital 48 kHz
Dolby Digital Plus 48 kHzDolby
TrueHD (Lossless) 48 kHz, 96 kHz, 192 kHz

DVD:
PCM: 48 kHz or 96 kHz, 16 bit or 24 bit PCM
AC-3: 48 kHz
DTS: 48 kHz or 96 kHz
MP2: 48 kHz

Youtube video = 48kHz

 

[capslock]

I waded into the 9038S thread but didn't read all 100+ pages. I gathered that the 9038S G3 comes with an Android app that allows to tweak, besides filters, a 2nd and 3rd harmonic compensation. Any idea how this works and if it is used in the Khadas Pro here?

 

[Gouwa]

Hi @amirm
Thanks for the great reviews again

Can you help check again the points below:
1) UNBAL RCA Performance: our measurement result with 116 SINAD but using any one of setups below:

1> A 4.4 to XLR-3 cable connection between AP555B and T2P device​

2> The external power isolation module on the​

The reason needing the additional setup for unbal RCA(and 3.5 Jack) is that the power comsuption of the T2P device comes quite high(450+mA) for a USB cable powered device and the setup ensure to cut the ground loopback between AP555 and T2P devcie. The BAL RCA with better noise cancellation ability and the additional setup comes not a needed.

2) Jitter Noise and Spectrunm: same additonal setup above will improve the result.

3) THD+N Ratio vs Frequency @48KHz(90KHz BW): thanks for the feedback, we already found the issue here and it's the register value of ESS ES9038Q2M lead different results. The comparisons measurement below:

As what you statement, it's out of the audible band but we will still improve this performance in the future.

4) 3.5 Jack Output: can you kindly, if possible, to help to measure again if still with same results? And you should have two T2P devices

The measurement result here:

Btw, the T2P bare board we shipped to you is just for your further information how we designed the product and we don't have a plan to sell it due the restitution of MQA licence, but we will launch Tone2 (non-Pro) in the future with DIY Kit bundle that similar with the Tone1.

And finally, here is the video tutorial for Knob Operations:

Thanks again for the great review and wish all the best for you and the ASR fans.

Good day!

Useful links:
1) Tone2 Pro User Manual
2) Tone2 Pro FAQ Page

 

[Lambda]

The problem for the average Joe is that they generally have no way of knowing unless they know what to look for.

Would be an interesting test? different operating systems and player with different sound up/down samplers enabled.

is not as technically 'perfect' but it doesn't have to be

Since its a digital filter it can be closes to perfect? it just needs more/longer processing?
I don't want to say something to stupid...
its probably FIR filter? so it needs some sort of memory and dsp cores?
the more the closer to perfect?
But would it introduce delay at some point?

 

[restorer-john]

Of course the upsampler could also be better. The problem for the average Joe is that they generally have no way of knowing unless they know what to look for.

The 22kHz filtering (full attenuation at 24kHz) is not as technically 'perfect' but it doesn't have to be in practice using music.

Blu-ray:
LPCM (Lossless) 48 kHz, 96 kHz, 192 kHz
Dolby Digital 48 kHz
Dolby Digital Plus 48 kHzDolby
TrueHD (Lossless) 48 kHz, 96 kHz, 192 kHz

DVD:
PCM: 48 kHz or 96 kHz, 16 bit or 24 bit PCM
AC-3: 48 kHz
DTS: 48 kHz or 96 kHz
MP2: 48 kHz

Youtube video = 48kHz

So, tell me, how much (as a rough precentage) of digital music distribution, (as in actual music that is listened to) is in those formats? How much is actually 16/44.1? You know the answer.

 

[Massimo]

3) THD+N Ratio vs Frequency @48KHz(90KHz BW): thanks for the feedback, we already found the issue here and it's the register value of ESS ES9038Q2M lead different results. The comparisons measurement below:

As what you statement, it's out of the audible band but we will still improve this performance in the future.

Will this improvement be by firmware update or new hardware?

 

[solderdude]

So, tell me, how much (as a rough precentage) of digital music distribution, (as in actual music that is listened to) is in those formats? How much is actually 16/44.1? You know the answer.

Alas I don't. How much music exists in 16/44.1 format you mean? In which time period ? Including streaming ? physical products only ?

I can only give a rough percentage of my own collection. I would say 95% of my music is 16/44.1 in various formats.
The display on my E30 is almost always showing 44.1 listening to music and 48 when viewing youtube.
For video I don't give a crap about audio SQ nor the codec used, don't watch music videos either... Only Amir's video reviews

 

[Lambda]

So, tell me, how much (as a rough precentage) of digital music distribution, (as in actual music that is listened to) is in those formats?

The question is what better 16/44.1 converted to 24/192* inside the DACs DSP
Or 16/44.1 converted to 24/192* inside the PC with nearly unlimited memory and processing power.
*or what ever the DAC internally using

Since Analog filters are not ideal and non linear plugins behave strange and can cause aliasing with 44.1khz for recording i generally use >96khz.
And the latency is better at 96khz...
I guess 48k is good enough and will almost never cause problems but hey, memory is cheap and processor are panty fast those days.

So at production and recording i mostly use "real" 96k
Playback only is most of the time 48k (youtube/streaming) upsampled to 96k

 

[Zerohour]

Hi @amirm

4) 3.5 Jack Output: can you kindly, if possible, to help to measure again if still with same results? And you should have two T2P devices
View attachment 114800

The measurement result here:
View attachment 114801

Btw, the T2P bare board we shipped to you is just for your further information how we designed the product and we don't have a plan to sell it due the restitution of MQA licence, but we will launch Tone2 (non-Pro) in the future with DIY Kit bundle that similar with the Tone1.

And finally, here is the video tutorial for Knob Operations:

Thanks again for the great review and wish all the best for you and the ASR fans.

Good day!

Useful links:
1) Tone2 Pro User Manual
2) Tone2 Pro FAQ Page

glad to see a manufacturer(?) reply! Was weirded out by the super low unbalanced power output, hopefully its just a defect/error on test unit.

Also, what will be the difference between Pro/non-Pro unit, if you don't mind sharing.

 

[elitesheep]

Hi @amirm
3) THD+N Ratio vs Frequency @48KHz(90KHz BW): thanks for the feedback, we already found the issue here and it's the register value of ESS ES9038Q2M lead different results. The comparisons measurement below:

Does that also fix the undesirable rolloff filtering behaviour?

 

[TimW]

It seems like an external power source may be required to get the performance Khadas's measurements are exhibiting.

 

[Hifihedgehog]

Will this improvement be by firmware update or new hardware?

My educated guess: firmware update. If it's a register value (i.e. "it's the register value of ESS ES9038Q2M"), that would refer to the bit values that they programmatically are sending to the DAC chip in the digital domain, so I would wager a firmware update could easily fix this problem.

 

[W1ll1eTheP1mp]

Hi @amirm
Thanks for the great reviews again

Can you help check again the points below:
1) UNBAL RCA Performance: our measurement result with 116 SINAD but using any one of setups below:

1> A 4.4 to XLR-3 cable connection between AP555B and T2P device​

2> The external power isolation module on the​

The reason needing the additional setup for unbal RCA(and 3.5 Jack) is that the power comsuption of the T2P device comes quite high(450+mA) for a USB cable powered device and the setup ensure to cut the ground loopback between AP555 and T2P devcie. The BAL RCA with better noise cancellation ability and the additional setup comes not a needed.

2) Jitter Noise and Spectrunm: same additonal setup above will improve the result.

3) THD+N Ratio vs Frequency @48KHz(90KHz BW): thanks for the feedback, we already found the issue here and it's the register value of ESS ES9038Q2M lead different results. The comparisons measurement below:
View attachment 114799

As what you statement, it's out of the audible band but we will still improve this performance in the future.

4) 3.5 Jack Output: can you kindly, if possible, to help to measure again if still with same results? And you should have two T2P devices
View attachment 114800

The measurement result here:
View attachment 114801

Btw, the T2P bare board we shipped to you is just for your further information how we designed the product and we don't have a plan to sell it due the restitution of MQA licence, but we will launch Tone2 (non-Pro) in the future with DIY Kit bundle that similar with the Tone1.

And finally, here is the video tutorial for Knob Operations:

Thanks again for the great review and wish all the best for you and the ASR fans.

Good day!

Useful links:
1) Tone2 Pro User Manual
2) Tone2 Pro FAQ Page

Hey. Will this be firmware updated? Im close to order one!

 

[Gabriel1]

Hi @amirm
Thanks for the great reviews again

Can you help check again the points below:
1) UNBAL RCA Performance: our measurement result with 116 SINAD but using any one of setups below:

1> A 4.4 to XLR-3 cable connection between AP555B and T2P device​

2> The external power isolation module on the​

The reason needing the additional setup for unbal RCA(and 3.5 Jack) is that the power comsuption of the T2P device comes quite high(450+mA) for a USB cable powered device and the setup ensure to cut the ground loopback between AP555 and T2P devcie. The BAL RCA with better noise cancellation ability and the additional setup comes not a needed.

2) Jitter Noise and Spectrunm: same additonal setup above will improve the result.

3) THD+N Ratio vs Frequency @48KHz(90KHz BW): thanks for the feedback, we already found the issue here and it's the register value of ESS ES9038Q2M lead different results. The comparisons measurement below:
View attachment 114799

As what you statement, it's out of the audible band but we will still improve this performance in the future.

4) 3.5 Jack Output: can you kindly, if possible, to help to measure again if still with same results? And you should have two T2P devices
View attachment 114800

The measurement result here:
View attachment 114801

Btw, the T2P bare board we shipped to you is just for your further information how we designed the product and we don't have a plan to sell it due the restitution of MQA licence, but we will launch Tone2 (non-Pro) in the future with DIY Kit bundle that similar with the Tone1.

And finally, here is the video tutorial for Knob Operations:

Thanks again for the great review and wish all the best for you and the ASR fans.

Good day!

Useful links:
1) Tone2 Pro User Manual
2) Tone2 Pro FAQ Page

Hello, Amirm has suggested that the “CLOCK MODE” might be adjustable ! Please let me know if this is true, how to accomplish and if this indeed would be desirable? Thank you in advance, G.

 

[W1ll1eTheP1mp]

What was actually going on with the filter thing on 44.1 khz? I didnt quite understand it.

 

[Jimster480]

But buttons, yes, if you can hear 118 vs 100 Sinad, ok.

Basically my thoughts... it was really hard to hear the difference from the K1 to something better and that is only in the mid 90s iirc.

I don't see the purpose in it being so complex to operate. Also there is no reason to have this if you have a LG phone because its not really any better than the LG G8 default output (thankfully my phone).

 

[bigjacko]

What is the volume control? Is it rotary dac volume control or analog colume control?

 

[dtaylo1066]

Dial is silly. Too bad there is no volulme on the RCA analog output.

 

[Gouwa]

What is the volume control? Is it rotary dac volume control or analog colume control?

The preinstalled firmware with analog volume control only, and to support DAC software volume control, you will need to upgrade with dedicated firmware which we will release in the future.

More details:
https://www.khadas.com/post/tone2-pro-spec-update-s-pdif-out-more
https://www.khadas.com/tone2pro-faq

 

[W1ll1eTheP1mp]

The preinstalled firmware with analog volume control only, and to support DAC software volume control, you will need to upgrade with dedicated firmware which we will release in the future.

More details:
https://www.khadas.com/post/tone2-pro-spec-update-s-pdif-out-more
https://www.khadas.com/tone2pro-faq

Hey @Gouwa will the 48khz issue be fixed in an firmwareupdate?