Chord Electronics Qutest DAC - Official Thread

[Music Alchemist]

Actually, the digital power amp has been discussed extensively in the DAVE thread intended to use the dual coaxial output, but I’m still fuzzy on the details regarding the DAVE’s role with the digital power amp.

Could you summarize how it works as far as you know?

I don't understand why or how it would have a digital output if it's driving passive speakers.

 

[x RELIC x]

Could you summarize how it works as far as you know?

I don't understand why or how it would have a digital output if it's driving passive speakers.

No I can’t, that’s why I didn’t... lol. All I know is that the four (edited correction) digital coaxial outputs from DAVE was intended for the digital power amp. That’s all I know.

 

[Music Alchemist]

All I know is that the dual digital coaxial out was intended for the digital power amp.

Let's get things straight here. The DAVE only has digital inputs, not outputs, right? But if you are saying that the digital power amp has digital outputs (in addition to digital inputs, which I am assuming it will have so it can be paired with the Blu MkII) and could be paired with the DAVE, doesn't that mean it would be before it in the chain, with the DAVE at the end? How would it drive speakers then?

 

[x RELIC x]

Let's get things straight here. The DAVE only has digital inputs, not outputs, right? But if you are saying that the digital power amp has digital outputs (in addition to digital inputs, which I am assuming it will have so it can be paired with the Blu MkII) and could be paired with the DAVE, doesn't that mean it would be before it in the chain, with the DAVE at the end? How would it drive speakers then?

To be clear... DAVE has four digital coaxial BNC outputs. Look at the manual.

Edit: FOUR digital outputs.

 

[Music Alchemist]

To be clear... DAVE has two digital coaxial BNC outputs. Look at the manual.

They should update their website, then, because they only list digital inputs and analog outputs in the features section.

Okay, so based on what you said, the chain could look like Blu MkII > DAVE > digital power amp. That makes sense now.

(I must have misinterpreted what Rob said about "a single DAC amplifier"...)

If that's true, then it would appear that it's not a DAC/power amp; just a power amp with digital input that uses a DAC with digital output.

...But wait... If that's true, doesn't that mean it cannot be used with the Qutest? (Which only has analog output.)

@Rob Watts
All this is very confusing. If you could clarify, it would be appreciated.

 

[x RELIC x]

They should update their website, then, because they only list digital inputs and analog outputs in the features section.

Okay, so based on what you said, the chain could look like Blu MkII > DAVE > digital power amp. That makes sense now.

It’s likely not listed as the digital amp isn’t available yet so the feature is currently dead.

You should bring this to the DAVE thread to keep the Qutest thread on track. I don’t think the Qutest can use the digital amps digital inputs.

 

[Rob Watts]

They should update their website, then, because they only list digital inputs and analog outputs in the features section.

Okay, so based on what you said, the chain could look like Blu MkII > DAVE > digital power amp. That makes sense now.

(I must have misinterpreted what Rob said about "a single DAC amplifier"...)

If that's true, then it would appear that it's not a DAC/power amp; just a power amp with digital input that uses a DAC with digital output.

...But wait... If that's true, doesn't that mean it cannot be used with the Qutest? (Which only has analog output.)

@Rob Watts
All this is very confusing. If you could clarify, it would be appreciated.

The only difference between Dave's DX output (that is the digital OP to connect to a DX power pulse array amp) and a regular 705/768 kHz signal, is the DX has volume control information embedded in the user data. So when Dave is used with a DX power amp then Dave becomes a DX pre-amp, as it controls the volume.
Qutest will accept the DX data, but will ignore the volume data, as Qutest does not have a volume control - it is a fixed OP DAC.

 

[Music Alchemist]

The only difference between Dave's DX output (that is the digital OP to connect to a DX power pulse array amp) and a regular 705/768 kHz signal, is the DX has volume control information embedded in the user data. So when Dave is used with a DX power amp then Dave becomes a DX pre-amp, as it controls the volume.
Qutest will accept the DX data, but will ignore the volume data, as Qutest does not have a volume control - it is a fixed OP DAC.

What I'm trying to figure out is how the Qutest would work with a DX power amp. (Or power pulse array / digital power amp...all these names. lol)

Normally, I would connect the DAC to a preamp, which would then be connected to a power amp. The Qutest only has digital inputs and analog outputs, so how would it connect to a DX power amp? The DAC comes before the amp, so I'm not sure what the Qutest's ability to accept DX data has to do with this. What would the chain look like?

What does DX stand for?

 

[Rob Watts]

What I'm trying to figure out is how the Qutest would work with a DX power amp. (Or power pulse array / digital power amp...all these names. lol)

Normally, I would connect the DAC to a preamp, which would then be connected to a power amp. The Qutest only has digital inputs and analog outputs, so how would it connect to a DX power amp? The DAC comes before the amp, so I'm not sure what the Qutest's ability to accept DX data has to do with this. What would the chain look like?

What does DX stand for?

Qutest is not a DX pre-amp, it's just a fixed level DAC! It has no DX digital outputs, and won't decode the volume on a DX input.
DX is just a term...

 

[Music Alchemist]

Qutest is not a DX pre-amp, it's just a fixed level DAC! It has no DX digital outputs, and won't decode the volume on a DX input.

So basically, the only Chord DACs that can work with any of the upcoming digital power amps are those that have digital outputs? Is the DAVE the only one?

I was under the impression before that the digital power amps could be used with more affordable DACs.

 

[Rob Watts]

Only Dave has DX outputs...

 

[Music Alchemist]

Only Dave has DX outputs...

Alright, thanks for clarifying.

So all that is a moot point for the Qutest, and I would have to use a conventional power amp with it.

 

[Jimi Zine]

The Qutest doesn't not transmit anything digital, it only receives it. Your question is really: Can a Mac send DSD?

The answer is: There isn't any native DSD support in MacOS. You need software that can transmit DSD such as Audirvana Plus or Roon. Such software doesn't have to use DoP though, but can send DSD directly. DoP is used to fool hardware into treating DSD as if it were PCM, allowing easy transmission, even though the actual data is not PCM at all.

I realise this thanks, and use Audirvana 3 and HQ Player which allow for Native DSD playback (on OS X), which I agree allows for both DoP & Native DSD transmission (Exasound for instance).
The problem, and many others confirm this, is that on a mac, using DoP with the Mojo (and other Chord Dacs), whereas DSD64 plays perfectly, DSD128 & 256 exhibit audio dropouts using this method. This is a significant drawback/flaw in the way the chord DACs receive DSD signals and is something Chord seems to want to ignore rather than focus on in any way.


Notes
a) I have used other DSD Dacs and they have not exhibited this audio drop out problem, so surely it's the way the Mojo or Qutest works with OS X, rather than "the source sending faulty data", which implies it's somehow a problem with my mac or software or files, rather than the Chord Electronics equipment...

b) Will the Qutest receive DSD on a mac natively or via DoP (assuming the DSD will be native DSD either way, rather than a PCM conversion)?
ANSWER - Windows Natively with ASIO driver / Mac DoP it seems ??

c) Exasound have implemented ASIO drivers with OS X (if not iOS), so native DSD transmission from a mac is possible
ANSWER - SILENCE....

 

[elviscaprice]

The only difference between Dave's DX output (that is the digital OP to connect to a DX power pulse array amp) and a regular 705/768 kHz signal, is the DX has volume control information embedded in the user data. So when Dave is used with a DX power amp then Dave becomes a DX pre-amp, as it controls the volume.
Qutest will accept the DX data, but will ignore the volume data, as Qutest does not have a volume control - it is a fixed OP DAC.

Alright, thanks for clarifying.

So all that is a moot point for the Qutest, and I would have to use a conventional power amp with it.

You still missed it, or I did. See Rob's post above. I assume the Qutest can accept the DX data and out put as analog, since it can't act as a preamp. but there would be some control with the 3 selections for different voltage (or would that be bypassed directly to op amp), in addition from the DX amp? So you would either need to control the volume with software beforehand, like JRiver, or afterwards on a preamp in analog. Confusing since I don't understand how the Qutest will have the power to output a stronger power signal.or allow pass thru??

 

[Music Alchemist]

You still missed it, or I did. See Rob's post above. I assume the Qutest can accept the DX data and out put as analog bypassing the Qutest amp section, since it can't act as a preamp. So you would either need to control the volume with software beforehand, like JRiver, or afterwards on a preamp in analog.

The way it was described, it seemed like the following to me:

• The DX amps only have digital inputs, as well as analog outputs in the form of speaker taps...
  
• ...and the DAVE is the only Chord DAC that outputs DX data via its digital outputs...
• ...so the fact that the Qutest can accept DX data via its digital inputs has no relevance, especially since it cannot be connected to the DX amp.

@Rob Watts
If any of this is incorrect, let me know.