Chord DACs

That is a pity, because there's no way I'll soend £500 on Poly plus buying Mojo, just for mobile use (and Hugo 2 even without Its Poly equivalent is out of contention for the same reason, quite apart from the fact that the H2 combination will be larger and heavier so less portable.

analogmusic posted:

 DAVINA - finally should bring us much closer to experiencing digital music really sounds like "studio masters".

It should put Chord firmly on the map for the next 20 years or so, as competitors try to figure out how Rob Watts did it. 

Chord DAC’s won’t get you closer to the original master tape, quite the opposite. They are actually extremely powerful and accurate digital synthesizers. They utilise/process information stored in memory to create the output.

I use a Mojo. With sparse instrumentation and vocals it sound superb, presumably the processor is able to cope with a small number of instruments. Combine a large number of instruments with complex rhythms, it seems to fall down, presumably the processor/memory simply isn’t able to cope.

??????

Simon-in-Suffolk posted:

??????

Rob Watts: OK, the interpolation filter’s job in a DAC is to re- create the missing parts of the original analogue signal - the signal in between one sample and the next. This is done with an FIR filter. In a simple way, a FIR filter consists of a data memory (this stores previous data samples) and a coefficient memory (this is a fixed memory with all of the coefficients that the filter algorithm has created).

?????

fatcat posted:

analogmusic posted:

 DAVINA - finally should bring us much closer to experiencing digital music really sounds like "studio masters".

It should put Chord firmly on the map for the next 20 years or so, as competitors try to figure out how Rob Watts did it. 

Chord DAC’s won’t get you closer to the original master tape, quite the opposite. They are actually extremely powerful and accurate digital synthesizers. They utilise/process information stored in memory to create the output.

I use a Mojo. With sparse instrumentation and vocals it sound superb, presumably the processor is able to cope with a small number of instruments. Combine a large number of instruments with complex rhythms, it seems to fall down, presumably the processor/memory simply isn’t able to cope.

No idea about Mojo as I've never heard it. To my ears, and others' I know who have heard it , Hugo(1) is very natural ('analogue') sounding compared to, say, DAC in ND5XS. Dave is simply Wow', naturalness with amazing clarity, and improved 3D soundstaging. I've no idea if this fits with your first paragraph as I don't have access to the original mastertape for anything (and anyway I suspect that the final mastered version is often itself is not always the same as the original mastertape.

I would definitely agree that the Hugo sounds very natural indeed and yes sort of "analogue"

I wonder if anyone can help in my use of the Hugo?

I am currently using it with the volume control (set at turquoise as suggested) but am I right in saying you can bypass the volume?  and if so does anyone know the output level ?  If it's 3v, the same as 2Qute, then that will be too high for my amps

And how do most power the Hugo?  I am currently charging it and then unplugging it from mains to use, then plugging back in to re-charge.  I am also switching the Hugo off when it's not being used but that's quite a pain as it doesn't 'remember' the settings for input/volume

fatcat posted:

Simon-in-Suffolk posted:

??????

Rob Watts: OK, the interpolation filter’s job in a DAC is to re- create the missing parts of the original analogue signal - the signal in between one sample and the next. This is done with an FIR filter. In a simple way, a FIR filter consists of a data memory (this stores previous data samples) and a coefficient memory (this is a fixed memory with all of the coefficients that the filter algorithm has created).

?????

An FIR filter is a method that transforms the response of a series of sample values into a series of imaginary infinitely narrow points of time samples... this is required mathematically to reconstruct the original analogue continuous signal from a sampled series... of course this can be never absolutely accurate as you can’t have infinitely narrow points in time, hence the differing effectiveness of FIR or IIR filters used in DACs..( and the FPGA processor allows a pretty accurate FIR reconstruction filter in the Hugo with minimal electrical and mathematical noise side effects). However to be clear no data can be reconstructed if it’s not encoded in the original sampled sequence, that would break the laws of entropy and the sample theorem... effectively one would would be creating substance from thin air .... great for science fiction, but alas not for us.

Nina posted:

I would definitely agree that the Hugo sounds very natural indeed and yes sort of "analogue"

I wonder if anyone can help in my use of the Hugo?

I am currently using it with the volume control (set at turquoise as suggested) but am I right in saying you can bypass the volume?  and if so does anyone know the output level ?  If it's 3v, the same as 2Qute, then that will be too high for my amps

And how do most power the Hugo?  I am currently charging it and then unplugging it from mains to use, then plugging back in to re-charge.  I am also switching the Hugo off when it's not being used but that's quite a pain as it doesn't 'remember' the settings for input/volume

My recellection is there is no benefit in disabling the volume control (setting to 'line level' IIRC), so best leave as it come - it remembers your setting when you turn off. 

And there is no detriment to sound quality from Hugo leaving the power supply on and connected, so that is how I used it, and again IIRC that is quite a common approach. (Of course, different if you find the power supply causes interference with something else via the mains, though I don't recall anyone reporting that.)

Simon-in-Suffolk posted:

fatcat posted:

Simon-in-Suffolk posted:

??????

Rob Watts: OK, the interpolation filter’s job in a DAC is to re- create the missing parts of the original analogue signal - the signal in between one sample and the next. This is done with an FIR filter. In a simple way, a FIR filter consists of a data memory (this stores previous data samples) and a coefficient memory (this is a fixed memory with all of the coefficients that the filter algorithm has created).

?????

However to be clear no data can be reconstructed if it’s not encoded in the original sampled sequence, that would break the laws of entropy and the sample theorem... effectively one would would be creating substance from thin air .... great for science fiction, but alas not for us.

Are the value of the coefficients ( created by the filter algorithm), derived from the original sampled sequence.

Innocent Bystander posted:

My recellection is there is no benefit in disabling the volume control (setting to 'line level' IIRC), so best leave as it come - it remembers your setting when you turn off. 

And there is no detriment to sound quality from Hugo leaving the power supply on and connected, so that is how I used it, and again IIRC that is quite a common approach. (Of course, different if you find the power supply causes interference with something else via the mains, though I don't recall anyone reporting that.)

Thanks IB

However my Hugo doesn't seem to remember my settings when I switch it off

Nina posted:

Innocent Bystander posted:

My recellection is there is no benefit in disabling the volume control (setting to 'line level' IIRC), so best leave as it come - it remembers your setting when you turn off. 

And there is no detriment to sound quality from Hugo leaving the power supply on and connected, so that is how I used it, and again IIRC that is quite a common approach. (Of course, different if you find the power supply causes interference with something else via the mains, though I don't recall anyone reporting that.)

Thanks IB

However my Hugo doesn't seem to remember my settings when I switch it off

Hmmm, I thought itbdid, but switched off very rarely, so my apologies for mis-remembering. With the 'line' output setting, I think the level is still indicated by the colour, just not adjustable. But for the actual level you'll have to search through the specs or contact Chord.

Thanks IB

So leaving the Hugo switched on 24/7 is ok with it permanently connected to the mains ?

I think I'm still stuck in 'valve mode' where I wouldn't leave anything on 

That is what I did, and I believe that's what a lot of others  do (especially on this forum being in the habit from Naim gear), but periodically turn off and let discharge.

However early in this thread @Simon-in-Suffolk, who had had his Hugo repaired due to IIRC a battery fault, said something about advice having changed - it would be as well to check with him.

Yes I understand, via my dealer, the advice from Chord is that it’s best to discharge the Hugo from time to time. I switch mine off also when not in use. Originally the advice was you could leave powered up and charging 24/7.

fatcat posted:

Simon-in-Suffolk posted:

fatcat posted:

Simon-in-Suffolk posted:

??????

Rob Watts: OK, the interpolation filter’s job in a DAC is to re- create the missing parts of the original analogue signal - the signal in between one sample and the next. This is done with an FIR filter. In a simple way, a FIR filter consists of a data memory (this stores previous data samples) and a coefficient memory (this is a fixed memory with all of the coefficients that the filter algorithm has created).

?????

However to be clear no data can be reconstructed if it’s not encoded in the original sampled sequence, that would break the laws of entropy and the sample theorem... effectively one would would be creating substance from thin air .... great for science fiction, but alas not for us.

Are the value of the coefficients ( created by the filter algorithm), derived from the original sampled sequence.

The value of coefficients or taps represent the series of sample values after an imaginary infinitely narrow pulse (delta function)  is passed through a filter, therefore the filter function can be achieved by multiplying a window on the original sample stream by the sample values of the filter response (usually from a lookup table). The higher the number of taps / coefficients, the more accurate the filter response will be (the bigger the multiplication window) and therefore will introduce less digital errors to the filtered signal.

In the limit the response of the ADC low pass filter and the DAC low pass filter should be matched, but I think in practice seldom is and possibly has marginal accuracy benefit.

Simon-in-Suffolk posted:

Yes I understand, via my dealer, the advice from Chord is that it’s best to discharge the Hugo from time to time. I switch mine off also when not in use. Originally the advice was you could leave powered up and charging 24/7.

this should be done with all re-chargable  devices,  if possible avoid charging if the ventilation at the device  is poor

At some point though maybe the most accurate Dac will expose the limitations of the rather Basic ADC used in  the studio ?

Is the actual accuracy of the master and the ability to replicate it really that important?

If you consider digital photography, the equivalent of the master is the raw file. The vast majority of people don’t print or view the raw file, as, while containing all the details, it appears flat, dull and lifeless. The raw file is usually modified in photo processing software to suit users taste, or modified in camera and converted to Jpeg. My camera will output different images dependant on setting (Landscape, Portrait, Standard, Neutral), all images are different and none the same as the raw image.

Similarly, the Hugo 2 has 4 user selectable filters, outputting different sonic signatures, which is a very useful feature. But, obviously they can’t all (probably none) represent be a facsimile of the master recording or the music recorded.

At what stage does the manipulation of the sonic signature take place, at the beginning of the waveform shape calculation or later on?

Another statement from John Franks re the Poly ..

”Sorry guys it won’t be possible to use poly with anything other than a Mojo. As Poly reads usb back data from Mojo in order to enable itself. We will be bringing out a comparable unit for Dave and Hugo2 and even the TT too in due course.”

Given the teething trouble they seem to be having with software on the Poly it’s possibly not a bad thing to have to wait a bit! 

likesmusic posted:

Another statement from John Franks re the Poly ..

”Sorry guys it won’t be possible to use poly with anything other than a Mojo. As Poly reads usb back data from Mojo in order to enable itself. We will be bringing out a comparable unit for Dave and Hugo2 and even the TT too in due course.”

Given the teething trouble they seem to be having with software on the Poly it’s possibly not a bad thing to have to wait a bit! 

Yes, I had seen that - however my own interest in Poly wasn't getting one early, but in having only to buy one device to use mainly at home but by only adding the not horrendously expensive Mojo it I would have a fantastic mobile music solution - against which the cost of Mojo and Poly combined is far worse value, and much harder to justify for my very limited mobile use. And of course, only if Poly is good enough for use as the main system source.

Innocent Bystander posted:

likesmusic posted:

Another statement from John Franks re the Poly ..

”Sorry guys it won’t be possible to use poly with anything other than a Mojo. As Poly reads usb back data from Mojo in order to enable itself. We will be bringing out a comparable unit for Dave and Hugo2 and even the TT too in due course.”

Given the teething trouble they seem to be having with software on the Poly it’s possibly not a bad thing to have to wait a bit! 

Yes, I had seen that - however my own interest in Poly wasn't getting one early, but in having only to buy one device to use mainly at home but by only adding the not horrendously expensive Mojo it I would have a fantastic mobile music solution - against which the cost of Mojo and Poly combined is far worse value, and much harder to justify for my very limited mobile use. And of course, only if Poly is good enough for use as the main system source.

My Motorola Moto E (133 Euro) feeds a Mojo via a simple usb cable.

Nice, good sound.

Batteries work for the full day.

Ardbeg10y posted:

Innocent Bystander posted:

likesmusic posted:

Another statement from John Franks re the Poly ..

”Sorry guys it won’t be possible to use poly with anything other than a Mojo. As Poly reads usb back data from Mojo in order to enable itself. We will be bringing out a comparable unit for Dave and Hugo2 and even the TT too in due course.”

Given the teething trouble they seem to be having with software on the Poly it’s possibly not a bad thing to have to wait a bit! 

Yes, I had seen that - however my own interest in Poly wasn't getting one early, but in having only to buy one device to use mainly at home but by only adding the not horrendously expensive Mojo it I would have a fantastic mobile music solution - against which the cost of Mojo and Poly combined is far worse value, and much harder to justify for my very limited mobile use. And of course, only if Poly is good enough for use as the main system source.

My Motorola Moto E (133 Euro) feeds a Mojo via a simple usb cable.

Nice, good sound.

Batteries work for the full day.

What I saw as benefit of Poly doubling at home and travel is my entire music collection on micro-SD card (eventually all on one when/if capacity reaches 1TB, but maybe on 3 x400GB now), so all my music, in its highest quality, and with the same control software, is available travelling and at home, without having to think in advance what music I might fancy, nor copy things across etc. But as indicated only relevant if Poly is good enough for home use - and, unless Chord change things, seemingly a non-starter anyway as it is locked to Mojo.

To allow me to have the Hugo switched on all the time and not to keep plugging it in/out of the mains supply I have purchased an electronic timer socket so I can plug it in all the time and just have the timer come on/off a few times throughout the day to keep the battery topped up

Nina posted:

To allow me to have the Hugo switched on all the time and not to keep plugging it in/out of the mains supply I have purchased an electronic timer socket so I can plug it in all the time and just have the timer come on/off a few times throughout the day to keep the battery topped up

I predict howls of protest from those who predict that the timer will degrade your sound quality to mush! Maybe worth a careful listen with and without to establish if this is an issue for you, especially if the timer is on the same mains circuit as the rest of your HiFi.

ChrisSU posted:

Nina posted:

To allow me to have the Hugo switched on all the time and not to keep plugging it in/out of the mains supply I have purchased an electronic timer socket so I can plug it in all the time and just have the timer come on/off a few times throughout the day to keep the battery topped up

I predict howls of protest from those who predict that the timer will degrade your sound quality to mush! Maybe worth a careful listen with and without to establish if this is an issue for you, especially if the timer is on the same mains circuit as the rest of your HiFi.

Hi Chris

The idea I had was to have the timer come on to charge the Hugo when the Hugo (and the rest of the system) is not in use, say 3-5am each day