Khadas Tone2 Pro Review (DAC & Amp)

[staticV3]

Big volume knob is a big plus for some

Also what dongle reaches 118 SINAD?

The Meizu HiFi (116.8) and HiFi Pro (116.0) get pretty close, provided that you have clean 5V: https://zhuanlan.zhihu.com/p/94991395

The 9038D is between 117.5 and 118.5: https://e1dashz.wixsite.com/index/9038d

The Luxury&Precision W2 is reaching 119dB SINAD: https://www.l7audiolab.com/f/information-update-of-lp-w2/

 

[Atanasi]

An alternative for a combined unbalanced-balanced connector would be the 4.4mm jack. It would need an adapter for converting both to RCA and XLR. Or an additional 3.5mm for unbalanced would be more compatible if there is space.

 

[flAked]

I have the Tone 2 Pro with AKG K712 and I am wondering which AMP would be best, considering that the balanced RCA seems to be better. I could buy the adapter cable BRCA to XLR and get an AMP with XLR-Input, and possible mod my AKGs for a fully balanced chain. Or just use the unbalanced RCA.

I guess there is no way to convert the signal from the XLR adapter cable to unbalanced regular RCA into an DAC?

solderdude mapped out that 1W/32Ohms are recommended for these headphones and there aren't many AMPs in the 100-200eur price bracket with that power and good review? Magni Heresy is out of stock in Europe, Atom Amp would be 150eur with shipping.

 

[somebodyelse]

Can't really see the advantage of this one over 'premium dongles' with similar power like the Sparrow or the Lotoon S1. Creative Xfi Amp delivers also 370mW at 32Ohm and 55mW at 300 Ohm and has volume control buttons at half the cost.

How many premium dongles have balanced line outs as well as headphones, and spdif input? Last I looked the docs hadn't appeared for the 40 pin header or the fpc connectors, but for many the possibilities those gave was a major advantage of the Tone 1 over the competition.

 

[trl]

What is the DAC used?

Edit: apparently "ESS ES9038Q2M +xmos+ x4 amp OPA1612 amp" - can anyone confirm?

"At its heart of digital processing stays a powerful ESS 9038 Q2M chipset that is working in a 4-channel balanced configuration." Source: https://soundnews.net/sources/dacs/khadas-tone-2-pro-review-khadas-1-hi-end-dac-market-0/.

 

[staticV3]

I have the Tone 2 Pro with AKG K712 and I am wondering which AMP would be best, considering that the balanced RCA seems to be better. I could buy the adapter cable BRCA to XLR and get an AMP with XLR-Input, and possible mod my AKGs for a fully balanced chain. Or just use the unbalanced RCA.

I guess there is no way to convert the signal from the XLR adapter cable to unbalanced regular RCA into an DAC?

solderdude mapped out that 1W/32Ohms are recommended for these headphones and there aren't many AMPs in the 100-200eur price bracket with that power and good review? Magni Heresy is out of stock in Europe, Atom Amp would be 150eur with shipping.

It's possible to create an adapter from 3pin XLR to 2pin RCA, by just leaving the Signal- end disconnected, but you'd lose half your volume and the common mode rejection of a balanced connection in the process.
In short: there's no advantage to BalRCA->XLR->RCA compared to a simple RCA connection between Tone2 and Amp.

Here's how much power the K712 needs according to referenceaudioanalyzer:

It's pretty easy to modify the K712 for use with balanced Amps. You can punch out the 3pin mini XLR connector and just glue in a 4pin mini XLR connector instead. The mod is completely seamless, though you'd have to source a 4pin mini XLR balanced cable somewhere. Those are not readily available.

 

[elitesheep]

Many thanks for the measurements.

Which filters correspond to which on the graph? You have 8 results but there are only 7 selectable filters (page 11 of the manual).

I agree that the wheel interface is a bit naff, but after you've set your preferred filter and gain you're unlikely to change anything except the volume I would have thought. I feel the biggest annoyance is having to refer to the manual for what each of the LED positions are, I don't really see that a small LCD would have been that hard to implement.

 

[Nango]

How many premium dongles have balanced line outs as well as headphones, and spdif input? Last I looked the docs hadn't appeared for the 40 pin header or the fpc connectors, but for many the possibilities those gave was a major advantage of the Tone 1 over the competition.

Op wanted to use with a mobile phones, no need for spdif input.

 

[Vini darko]

That jitter graph is the weirdest I've seen here I think. Whats going on there? (Asking from a technical perspective)

 

[capslock]

The Meizu HiFi (116.8) and HiFi Pro (116.0) get pretty close, provided that you have clean 5V: https://zhuanlan.zhihu.com/p/94991395

The 9038D is between 117.5 and 118.5: https://e1dashz.wixsite.com/index/9038d

The Luxury&Precision W2 is reaching 119dB SINAD: https://www.l7audiolab.com/f/information-update-of-lp-w2/

Are there any non-manufacturer measurements of the 9038D? Amir's measured the 9038S much worse than the manufacturer has (unless he had a different version, as the manufacturer's plots are for a G3).

 

[staticV3]

Are there any non-manufacturer measurements of the 9038D? Amir's measured the 9038S much worse than the manufacturer has (unless he had a different version, as the manufacturer's plots are for a G3).

Amirm was sent a 9038D a couple months ago, but there's a long waiting list on ASR of course.
Official specs for the 9038S G1 is THD+N of <.0004%, which is right in line with Amirm's measurements.
Don't compare ASR's G1 measurements with the G3 measurements on the product page.

EDIT: sorry for going off-topic.

 

[RiflemanFirst]

Seems to be a very solid performer with lots of features for the form factor and price. Any chance of a re-test with a dedicated power supply on the 2nd USB-C input to compare measurements? Really considering buying one to finally give MQA and balanced a try with my HD660S.

 

[trl]

Here's how much power the K712 needs according to referenceaudioanalyzer:

So not a job for Tone 2. Looks like an amp with more than 1W/ch. would be a better match. I also speak from experience here too.

 

[Lambda]

This might have been discussed several times before so i would appreciate if someone can point me to the explanations.

The non ideal filter seams to causes problems and reduces performance close to the filter frequency.
Why not use 196Khz with all DACs? this would move the "problem" far outside the audible range.

An analog low pass @~40Khz could easily take care of remaining digital filter artifacts without compromising the audible band.

 

[somebodyelse]

Op wanted to use with a mobile phones, no need for spdif input.

Are you posting in the right thread? OP in this one is amirm doing a review.

 

[Nango]

Are you posting in the right thread? OP in this one is amirm doing a review.

Sorry, I thought someone mentioned here he wanted to use this with a LG V40 mobile phones.

 

[Labjr]

Be sure to add the cost of the cable adapters while comparing value. I don't personally see a scenario where I would use this product.

 

[anon2k2]

I'm enjoying my blue one. As a little bonus, my wife just likes how it looks.

"It's very pretty," she said upon seeing it, "not like all the dumb black boxes you have all over the place."

"Hey, some of those dumb boxes are silver," was my retort.

 

[somebodyelse]

Be sure to add the cost of the cable adapters while comparing value. I don't personally see a scenario where I would use this product.

That's a fair point - $50 or $80 to be able to use the balanced outs is a bit steep. They had the bare connectors for ~$10 each if you wanted to solder your own, but those seem to have disappeared.

 

[respice finem]

Nice. Personally I'm generally skeptical about design-oriented gear, because it is often more looks (and price) than substance, but this one is a positive surprise. As to the complex settings structure, this is easier to handle on the RME for instance, but even here one would wish for a PC interface for the settings. This would probably not be hard to implement in a USB device.