[rr12267]

I was responding theoretically. I don’t even know if this is possible as I haven’t used the docking station.

My point was. To my knowledge with any device usb -> analog audio must have dac in between.

Miscommunication on my part, I was not referring to your first comment about USB but second about using 3.5mm output.

 

[glassmonkey]

Has anyone been able to extract the line level analogue output from a QP2R using just a USB C-to-stereo minijack (or dual RCA) adapter cable? I've been advised that it should be possible, and it would be a lot less expensive than buying an HB2.

Wouldn’t you then be double amping?

If you are doing analogue out of the USB C, then you are adding a DAC to the chain and you aren't taking advantage of DAC implementation of the QP2R or the amplification. With regards to double amping, the folks declaring this as 'bad' are wildly overstating their case. If you set one of the amplifiers to max (or the best sounding nearest point) and both units have decent distortion specifications, and you aren't getting clipping, then it's totally fine. Basically you are turning one into nearly equivalent of a line-level out, or one into a power amp with the other as a pre-amp. I've got double amping in my living room set-up, and in my serious review setup. Both sound excellent. The extra power may actually be beneficial. While I'd love to have a pure line-level out on my DAC, it is getting rarer and rarer for DAC/Amps to have a pure line-level output. I'm thinking of getting a Chord Qutest just to have this option.

 

[NehPets]

If using USB to analog output there must be a dac in between. Something like apple lightning to mini jack but then with usb c.

Why not just just the 3.5mm output? Ik hook it up to my amp that way all the time. Sounds great!

If you are doing analogue out of the USB C, then you are adding a DAC to the chain and you aren't taking advantage of DAC implementation of the QP2R or the amplification. With regards to double amping, the folks declaring this as 'bad' are wildly overstating their case. If you set one of the amplifiers to max (or the best sounding nearest point) and both units have decent distortion specifications, and you aren't getting clipping, then it's totally fine. Basically you are turning one into nearly equivalent of a line-level out, or one into a power amp with the other as a pre-amp. I've got double amping in my living room set-up, and in my serious review setup. Both sound excellent. The extra power may actually be beneficial. While I'd love to have a pure line-level out on my DAC, it is getting rarer and rarer for DAC/Amps to have a pure line-level output. I'm thinking of getting a Chord Qutest just to have this option.

That's what I thought as well, but it turns out that might not be the case; apparently, the USB Audio Device Class 3.0 spec. supports both analogue and digital audio.
Questyle say that the HB2 "... doesn’t process any audio signal, but only ensures wonderful music experience of the DAP is extended", so it seems that they're taking a signal from the QP2R's USB port and passing it directly to the HB2's analogue outputs, without any conversion.

 

[t69p]

Just remarked a strange problem with a 24bit/ 352kHz album on my QP2R.
Band: The Alan Parsons Project, the album is: I Robot in 352kHz/24bit from HDTracks, I remarked a background noise on all tracks from this album.
I do not have this noise on an AK380.

Any idea?
Thanks in advance for your info.

 

[514077]

Just remarked a strange problem with a 24bit/ 352kHz album on my QP2R.
Band: The Alan Parsons Project, the album is: I Robot in 352kHz/24bit from HDTracks, I remarked a background noise on all tracks from this album.
I do not have this noise on an AK380.

Any idea?
Thanks in advance for your info.

I only saw 176.2 for I Robot. When was 352 released? And sorry, I don't have an answer.

 

[t69p]

I now think its the quality of the recorded album. What I now also remarked is that the noise is also hearable on the AK380, but only at a very high sound level and there it's not so pronounced... did not remark the noise when I'm listening with the AK380.

 

[glassmonkey]

Just remarked a strange problem with a 24bit/ 352kHz album on my QP2R.
Band: The Alan Parsons Project, the album is: I Robot in 352kHz/24bit from HDTracks, I remarked a background noise on all tracks from this album.
I do not have this noise on an AK380.

Any idea?
Thanks in advance for your info.

This is a HiBy Linux OS problem. I have the same issue with the HiBy R3 on all 24/352 DXD albums. I noted this in my review on Audio Primate. Still need to relay this to HiBy. Let's all hit up JoeBloggs to get him to finish a few things.

 

[t69p]

Hello, thanks for your answer, just test the album on my Hiby R3. And yes I confirm it has the same noise. On the Hiby R6 (my son's dap) the noise is also perceptible but only with high level.

 

[514077]

This is a HiBy Linux OS problem. I have the same issue with the HiBy R3 on all 24/352 DXD albums. I noted this in my review on Audio Primate. Still need to relay this to HiBy. Let's all hit up JoeBloggs to get him to finish a few things.

Glad to hear Joe is still around. He was great to talk with on the FiiO threads.

 

[514077]

Hello, thanks for your answer, just test the album on my Hiby R3. And yes I confirm it has the same noise. On the Hiby R6 (my son's dap) the noise is also perceptible but only with high level.

What's it like? Is it a high pitched squeal? Or mainly some sort of noise?

 

[esauseesaw]

That's what I thought as well, but it turns out that might not be the case; apparently, the USB Audio Device Class 3.0 spec. supports both analogue and digital audio.
Questyle say that the HB2 "... doesn’t process any audio signal, but only ensures wonderful music experience of the DAP is extended", so it seems that they're taking a signal from the QP2R's USB port and passing it directly to the HB2's analogue outputs, without any conversion.

That is correct. I remember when Questyle first showed us the QP2R and explained dropping the line out. USB-C can transmit an analogue line out audio signal. This is exactly how the HB2 works. It has no DAC in it, the RCA analogue output just passes on the line out from the USB-C connection on the QP2R. This maintains the best S/N ratio because as you reduce volume on the QP2R it decreases SNR performance.

It is not true to assume that a USB-C output has to use a DAC. Here's how one site explains it...

'Analog audio can be converted with an onboard DAC and amplifier inside your phone then sent out through the port to a passive set of headphones or an adapter. For this to work, the device needs to support whats called "audio accessory mode" and the headphones or adapter are just "dumb" connections that pass along the signal.'

The problem I'm grappling with is, where to find to the correct connector! Many listed have a DAC built-in but it is unclear to me that, with the QP2R set to analogue out mode, if they automatically by-pass the DAC, as in 'audio accessory mode'. I will try to find one I know works and share here. If you find one before me please share too.

 

[NehPets]

That is correct. I remember when Questyle first showed us the QP2R and explained dropping the line out. USB-C can transmit an analogue line out audio signal. This is exactly how the HB2 works. It has no DAC in it, the RCA analogue output just passes on the line out from the USB-C connection on the QP2R. This maintains the best S/N ratio because as you reduce volume on the QP2R it decreases SNR performance.

It is not true to assume that a USB-C output has to use a DAC. Here's how one site explains it...

'Analog audio can be converted with an onboard DAC and amplifier inside your phone then sent out through the port to a passive set of headphones or an adapter. For this to work, the device needs to support whats called "audio accessory mode" and the headphones or adapter are just "dumb" connections that pass along the signal.'

The problem I'm grappling with is, where to find to the correct connector! Many listed have a DAC built-in but it is unclear to me that, with the QP2R set to analogue out mode, if they automatically by-pass the DAC, as in 'audio accessory mode'. I will try to find one I know works and share here. If you find one before me please share too.

Impeccable timing Matt.
I've just received a couple of different cables that I ordered so that I could investigate this very thing (after you'd pointed me in the direction). One is a Sony EC270 and the other, a TriLink branded cable that's supposed to be compatible with devices supporting 'audio accessory mode' (Moto Z family). As far as I can tell, without X-raying them, neither contains a DAC chip, but sadly, neither works; all I get is static and a few pops.

 

[esauseesaw]

Impeccable timing Matt.
I've just received a couple of different cables that I ordered so that I could investigate this very thing (after you'd pointed me in the direction). One is a Sony EC270 and the other, a TriLink branded cable that's supposed to be compatible with devices supporting 'audio accessory mode' (Moto Z family). As far as I can tell, without X-raying them, neither contains a DAC chip, but sadly, neither works; all I get is static and a few pops.

Thanks for the feedback! With the HB2 attached you can select analog or digital output in the set-up menu. I wondered if that appears as an option to select once the cable is connected and what it is currently set to?

 

[NehPets]

Thanks for the feedback! With the HB2 attached you can select analog or digital output in the set-up menu. I wondered if that appears as an option to select once the cable is connected and what it is currently set to?

The available settings for "HiFi Hub output" remain the same, either "digital" or "analog", regardless of whether the cable is attached or not. If I set the output to "digital" and then plug the cable in, it doesn't automatically change back to "analog". The (unsuccessful) tests that I've carried out were all done with the output set to "analog".

 

[esauseesaw]

The available settings for "HiFi Hub output" remain the same, either "digital" or "analog", regardless of whether the cable is attached or not. If I set the output to "digital" and then plug the cable in, it doesn't automatically change back to "analog". The (unsuccessful) tests that I've carried out were all done with the output set to "analog".

OK, thanks. I want to crack this. It must be possible as the HB2 takes an analogue line out. Will update with my findings asap...