Chords New M -Scaler

[auricgoldfinger]

1 hour ago, Sloop John B said:

 

Indeed it is strange that for some enthusiasts the proof of the pudding is not in the eating but rather in assessing the recipe. 

 

.sjb

 

+1

[auricgoldfinger]

43 minutes ago, mav52 said:

Lets stay on topic.   We are drifting like a bad clock

 

Thank you!

[auricgoldfinger]

Here's more information from none other than Rob Watts himself for you guys to argue over.

 

 

 

So in summary - the M scaler is trying to reproduce the original bandwidth limited analogue signal perfectly without any changes - and because it is identical to a sinc function to 16 bit accuracy, it will do this perfectly to a better than 16 bit accuracy.

And yes my DAC's are different - they do not use DSD but pulse array for the DAC conversion - and this is done so that the analogue has no distortion, no small signal non-linearity, and crucially no noise floor modulation, which is highly audible. DSD can't do this at all, nor will it ever be capable of doing this because of fundamental limitations to a 1 bit methodology.

As to DSD - a DSD bitstream looks nothing like the original analogue signal, as it adds huge amounts of out of band noise - with DSD64 you are -20 dB down at 100kHz. Moreover, if you simply low pass filter it, you get large amounts of distortion and noise, as the signal activity (switching) is signal dependent. DAC conversion is very very tough to do with low distortion and noise. Pulse array has constant switching activity, and has no added distortion, and more importantly no noise floor modulation. But pulse array requires PCM for it too work, so DSD must be converted to PCM; and we need to remove the dreadful RF and out of band noise with DSD too. So this noise gets removed, with a 220 dB stop-band filter - and we get complete removal of the HF noise and distortion that DSD creates.

Actually this is the same process in principle to PCM, in that the only way of recovering the original analogue signal before the DSD modulator is to filter it; I am trying to do exactly the same, recover the original analogue signal that was in the ADC....

Rob

 

https://www.head-fi.org/threads/hugo-m-scaler-by-chord-electronics-the-official-thread.885042/page-14#post-14397880

 

[auricgoldfinger]

23 minutes ago, austinpop said:

All this arguing about the math and the computation - FPGA vs. general-purpose CPUs and GPUs - is just noise. 

 

If I had my druthers, I'd declare all the HQPlayer discussion here as OT for this thread. Folks who want to continue that discussion should either take it back to the HQPlayer thread, or open a new thread. 

 

I agree completely.  Thank you for speaking up.

[auricgoldfinger]

Amidst all the FUD, I am surprised that no one has brought up the fact the HQP hangs and must be force closed almost every time the sample rate of a track changes.  While this issue is manageable when playing entire albums, it precludes the use of randomized play lists.  Oh, and there's also the wonderful HQP user interface.

 

Just sayin' since the thread is already so off topic.

 

[auricgoldfinger]

1 hour ago, Miska said:

Last time I checked they had just 120 dB stop-band attenuation, which in my opinion is not enough, or in other words I don't see reason why not do more. That's why I use 192 dB so that it matches at least 32-bit resolution... But anyway, I think there are so many aspects in a filter design, that single parameter like number of taps is pointless without all the other information...

 

 

Since your software seemingly can do no wrong, when do you plan to address the fact that HQP hangs and must be force closed almost every time the sample rate of a track changes?  Oh, and there's also the wonderful HQP user interface that causes most users to have to buy a Roon subscription.

 

As someone who has used HQP for 1.5+ years, I'd say it's not exactly ready for prime time.  Maybe it's time to stop taking pot shots at Chord on the M-Scaler thread and focus your valuable time, energy, and experience on your own product.

 

 

[auricgoldfinger]

2 minutes ago, Miska said:

Well, this is not HQPlayer thread, I'd like to stick to generic discussion about upsampling filters and such. But you are first to report such. Without knowing your OS/driver and having a log file I cannot help much.

 

Search your HQP thread.  I believe it has been reported many times by various users, and you have explained something along the lines of the way the software is designed causes this problem. 

[auricgoldfinger]

30 minutes ago, Miska said:

 

If you mean that it stops when you ask it do conflicting things, sure it will do that. It just stops playback and waits you to correct your conflicting request. It doesn't stop if you don't try to make conflicting requests. 

 

 

Does HQP hanging (stops playing) and requiring a force close when a 192/24 album comes to an end constitute a conflicting event?  How about when a 96/24 track rolls to a DSD track during a playlist and HQP hangs (stops playing) and requires a force close?

 

30 minutes ago, Miska said:

Maybe you wouldn't face such challenges if I'd reduce configuration flexibility of HQPlayer to the same level?

 

So my expectation that HQP should be able to cycle through a playlist without hanging (stop playing) when music formats change is somehow unreasonable?

[auricgoldfinger]

@The Computer Audiophile At what point do you declare that a thread is no longer on topic and that posts need to be split off to a separate thread?  Some very respected CA members have politely suggested it would be appropriate for this thread.  A fresh pair of eyes looking at this thread for information on the M-Scaler might be quite confused since there is little informed discussion of the M-Scaler product.  I am curious about the criteria as I am relatively new to CA.

[auricgoldfinger]

M-Scaler killer???  LOL 

 

 

[auricgoldfinger]

I guess some people don't appreciate irony.  The developer of HQ Player hijacked this M-Scaler thread to criticize the approach of Rob Watts and explain why HQ Player is better.  Among other things, he mentioned that the number of taps is a meaningless metric.  Nevertheless, he has released an update to HQ Player a mere 2 weeks later that includes a "mega" filter with 1 million taps for PCM and 16 million taps for SDM.

 

Go figure!