[gemmoglock]

I'm going to disagree with this. I think most Dual Chip DAC's use a single DAC for each channel, and the DAC circuitry would be ahead of the amplification, where options to use either Balanced or unbalanced would exist. Also most DAC chips output a balanced signal by default and require more circuitry (at least one opamp usually) to sum plus and minus signals for each channel.

Ok, we can agree to disagree, but I still think they would be shooting themselves in the foot by only having the benefit of dual DAC's for Balanced operation. There is no indication on the Data sheet http://www.pioneer-audiovisual.eu/sites/default/files/datasheets/english/XDP-30R.pdf either way, but typically THD and noise measurements are better for Dual configurations, and there is only one set of measurements. Also, what would really be the point? Balanced and Unbalanced mode is strictly an issue in the output circuitry, since the DAC's themselves output Balanced signals.

I agree - both DACs will be used, regardless of the selected output mode. A differential output is how audio DAC's so equipped are normally used. I spend enough of the day job looking at audio schematics...
The reason is simple - by using differential outputs, the DAC output is a locally controlled difference (voltage or current, depending on the DAC) between two points within the IC, neither of which needs to be regarded as an absolute with reference to the audio ground - they are referenced to each other. This always gives a cleaner output, and the single-ended form for conventional heaphones is then derived from the difference between the two outputs. Since the ground between the DAC and amplifier is not part of the equation it is therefore not contributing noise. For balanced headphones, it's only the driver stage that is reconfigured to remove the ground connection altogether and to separate the current paths for the left and right earphone drivers. At the same time, the balanced amplifier itself contributes less noise back onto the power supplies than a single-ended amplifier, albeit at the expense of increased power consumption. Clever stuff...

Cheers thanks for the explanations of how they work, it's really helpful! I've dropped an email as suggested and let's see

I have heard for some other DAPs e.g. Shanling M3S that one is disabled when running unbalanced, while some Fiios run both DACs for unbalanced out. Will share when I hear back!

 

[gemmoglock]

So I sent off an email to Pioneer and Onkyo. The Pioneer rep didn't understand my question while the Onkyo rep did and I hope his information is accurate.

Pioneer:
"The way the DAC work for the headphones jacks is one jack is for unbalanced and one Jack is balanced jack." Umm I know that there are two different jacks haha!

Onkyo:
"The twin DACs are used regardless of which port you use, balanced or unbalanced."

While waiting for my DP-S1 to ship, does anyone know if:
1) Can you install other region firmware on your DAP? For example Europe FW on US unit, Japan FW on Europe unit?
2) Does anyone know how upsampling to 192khz and requantising to 32bit work? Do you find that it works in real life for you?
3) Any difference between the digital filters?
4) What is jitter lock and what changes does it create?

Thank you!

 

[Trebor1966]

You got a wrong information - the twin DACs are only used with the balanced audio output - single ended there is only one DAC and one amplfier in use - it is 100% safe information

 

[BadBanana]

So I sent off an email to Pioneer and Onkyo. The Pioneer rep didn't understand my question while the Onkyo rep did and I hope his information is accurate.

Pioneer:
"The way the DAC work for the headphones jacks is one jack is for unbalanced and one Jack is balanced jack." Umm I know that there are two different jacks haha!

Onkyo:
"The twin DACs are used regardless of which port you use, balanced or unbalanced."

While waiting for my DP-S1 to ship, does anyone know if:
1) Can you install other region firmware on your DAP? For example Europe FW on US unit, Japan FW on Europe unit?
2) Does anyone know how upsampling to 192khz and requantising to 32bit work? Do you find that it works in real life for you?
3) Any difference between the digital filters?
4) What is jitter lock and what changes does it create?

Thank you!

You got a wrong information - the twin DACs are only used with the balanced audio output - single ended there is only one DAC and one amplfier in use - it is 100% safe information

No disrespect, but that does not say "only"...

A symetrical layout would also normally be applied in audio design when using one DAC per channel. Unfortunately the limited data on the ESS website doesn't help since the DAC can be used either way.

If I had the nerve, I'd open my player up and look at it with the scope, but I don't want to wreck it in the process.

 

[Trebor1966]

You got a wrong information - the twin DACs are only used with the balanced audio output - single ended there is only one DAC and one amplfier in use - it is 100% safe information

Here you find the different measurements single vs. balanced - look at the crosstalk and you will understand that the improvement balanced is based on the dual DACs usage:
http://ohm-image.net/data/audio/rmaa-onkyo-dp-s1-rubato-24-bit

 

[BadBanana]

Here you find the different measurements single vs. balanced - look at the crosstalk and you will understand that the improvement balanced is based on the dual DACs usage:
http://ohm-image.net/data/audio/rmaa-onkyo-dp-s1-rubato-24-bit

Interesting report. Why is the no-load unbalanced result almost 24dB better than the no-load balanced? I don't understand that detail. It seems counter-intuitive. Without a load, the output currents are very low, so low crosstalk would be expected for either mode but the differnece seems surprising.

The results with loads generally go the other way with balanced being better by almost 20dB apart from when using the Beyerdynamic DT880 units. Such a result would be expected, and teh variation with load impedance shows this to be probably due to the shared current paths in a single ended output.

 

[gemmoglock]

Here you find the different measurements single vs. balanced - look at the crosstalk and you will understand that the improvement balanced is based on the dual DACs usage:
http://ohm-image.net/data/audio/rmaa-onkyo-dp-s1-rubato-24-bit

Interesting report. Why is the no-load unbalanced result almost 24dB better than the no-load balanced? I don't understand that detail. It seems counter-intuitive. Without a load, the output currents are very low, so low crosstalk would be expected for either mode but the differnece seems surprising.

The results with loads generally go the other way with balanced being better by almost 20dB apart from when using the Beyerdynamic DT880 units. Such a result would be expected, and teh variation with load impedance shows this to be probably due to the shared current paths in a single ended output.

I just heard back from Ohm-image who did the measurements, and they said they aren't sure about the twin DAC status in unbalanced mode. From what little I understand, even a different amping design for unbalanced may also affect the measurements even if both DACs are activated.

Pioneer Australia FB has replied me, echoing Onkyo that both DACs are running for unbalanced too.
EDIT: Pioneer just got back after checking with "our manufacturers and product managers in Japan", ONLY 1 DAC is active for unbalanced.

Looks like I have to run a comparison between DP-S1 and the Hiby R3 (single but newer 9028Q2M vs dual 9018C2M). Sigh, I was looking for an excuse to cancel the R3 :/

 

[Trebor1966]

EDIT: Pioneer just got back after checking with "our manufacturers and product managers in Japan", ONLY 1 DAC is active for unbalanced.

MIssion accomplished

 

[gemmoglock]

EDIT: Pioneer just got back after checking with "our manufacturers and product managers in Japan", ONLY 1 DAC is active for unbalanced.

MIssion accomplished

Hahaha, it was quite likely but I wanted to be sure. I was hoping not to have to A-B the Hiby R3 with this but now.... But in real life which is what matters the unbalanced sounds great to most of us from the Onkyo/Pioneer

 

[downhillryder]

Hahaha, it was quite likely but I wanted to be sure. I was hoping not to have to A-B the Hiby R3 with this but now.... But in real life which is what matters the unbalanced sounds great to most of us from the Onkyo/Pioneer

I find this hard to believe and disappointing at the same time. Why package two expensive DACs and two output amps if only the balanced output benefits. A waste of money then for most users. Pioneer should be making this clear in their literature. So should reviewers. I demand a recount. May as well buy a cheaper thing like the Cayin N3. Gonna try find some balanced headphones see if I can hear a difference. Even though it was Pioneer support that provided the info I still can't quite believe it.

 

[BadBanana]

Even though it was Pioneer support that provided the info I still can't quite believe it.

I am sceptical too. No disrespect to Pioneer, but I very much doubt that this went to the people that would actually know the details in order to provide a response. They are too large a company for that. Front-line support would normally not even have access to detailed service literature for products.

Does anyone know how to open the player without permanent damage?

 

[gemmoglock]

I am sceptical too. No disrespect to Pioneer, but I very much doubt that this went to the people that would actually know the details in order to provide a response. They are too large a company for that. Front-line support would normally not even have access to detailed service literature for products.

Does anyone know how to open the player without permanent damage?

I am inclined to think that Pioneer's information is accurate, as they specifically told me they got back to Pioneer Japan before changing their reply to my query. However, this is not the first time a DAP uses both DACs only for balanced mode - Shanling and some others do it for various reasons.

So long as unbalanced sounds good (I can't wait to try mine), all's good A more positive way of looking at it is that if you get balanced cables, you can enjoy a bigger improvement in sound compared to using balanced on a single-DAC DAP (Cayin N3, Hiby R3).

Edit: I'm happy to notice that the ohm-image measurements showing real-life DP-S1 SNR hovering around 120db instead of the specified 115db. Will this be what make me finally ignore the Hiby R3 and it's UI/USB DAC advantages?

 

[gemmoglock]

I find this hard to believe and disappointing at the same time. Why package two expensive DACs and two output amps if only the balanced output benefits. A waste of money then for most users. Pioneer should be making this clear in their literature. So should reviewers. I demand a recount. May as well buy a cheaper thing like the Cayin N3. Gonna try find some balanced headphones see if I can hear a difference. Even though it was Pioneer support that provided the info I still can't quite believe it.

Take it easy, we only found out because I was nosy haha! If the unbalanced XDP-30R still sounds better than the N3 that's all that matters! And at least you know your balanced output has benefits - the Cayin N3 or other single-DAC DAPs with balanced won't hold a candle to your XDP-30R.

Edit: I'm happy to notice that the ohm-image measurements showing real-life DP-S1 SNR hovering around 120db instead of the specified 115db. Will this be what make me finally ignore the Hiby R3 and it's UI/USB DAC advantages?

 

[Trebor1966]

With the DP-S1 you will definitely hear a difference between single and balanced usage.
I own also several AKs - with the AK380 i can't hear a big difference - because also single ended both DACs are always in function.

 

[BadBanana]

So long as unbalanced sounds good (I can't wait to try mine), all's good A more positive way of looking at it is that if you get balanced cables, you can enjoy a bigger improvement in sound compared to using balanced on a single-DAC DAP (Cayin N3, Hiby R3).

At the end of the day, I agree. How it sounds is what matters. I am very happy with my DP-S1, and I currently using the single ended output with some Onkyo H500M headphones. I am looking at IEMs for the future and I'm currently sitting on the fence as to what to get and how much to spend, probably until I am next in Asia, simply because I need to save a bit of cash, and maybe try a couple of pairs. (I have good friends in HK who know the safe places to buy stuff at good prices.) Thinking maybe ATH-LS200is...

As for how the hardware is used, I am sure the designers chose whatever implementation is used for a reason, and given that the chips are there anyway it won't just be down to price. It's just the engineer in me that really wants to know the details...