[Mikey99]

sounds like you've already made your mind up - very scientific.

I have had many cases now where I was listening without realizing the m-scaler was in single BNC or pass through and quickly realized something was wrong. I have also done listening where I changed the mode without looking and had no problem identifying if it was in dual BNC or not. While not rigorous ABX, close enough. The difference is obvious.

 

[LWR999]

I have had many cases now where I was listening without realizing the m-scaler was in single BNC or pass through and quickly realized something was wrong. I have also done listening where I changed the mode without looking and had no problem identifying if it was in dual BNC or not. While not rigorous ABX, close enough. The difference is obvious.

As someone who incorrectly re-cabled their set up, and listened to an MScaler in single-BNC mode for a day; I can vouch for the fact that I knew something was not-as-good-as-it-should-be without the Mscaler doing it's thing

 

[Christer]

I have had many cases now where I was listening without realizing the m-scaler was in single BNC or pass through and quickly realized something was wrong. I have also done listening where I changed the mode without looking and had no problem identifying if it was in dual BNC or not. While not rigorous ABX, close enough. The difference is obvious.

I can add my five cents as well. But being "controversial Christer" one part of this post is another moan again about erratic behaviour of my HMS.
The last couple of days I have been changing BNC cables between my Qutest and HMS very often comparing two different BNC cables against the stock cable in my systems.
And yesterday after having changed cables and listening via a cable that in theory should improve on the stock cable and has done so regularly in my tests so far, a recording I know very well how it can and should sound suddenly sounded clearly worse via the expensive BNC than it had done via the stock cable just minutes before.
At first I was really puzzled as to why?
But after a short while of less than good SQ, I stood up from my listening chair and realized that my HMS had restarted with the OPSR light on red instead of the white 1 M taps setting.

Case closed.
No wonder it sounded worse.

I was not getting the 1 M taps and it was very obvious something was wrong even from the first bars of the work I was listening to.
At the moment I can't even remember what rate red is? But it did NOT sound good.

And what still puzzles me with this and the occasional light up of the wrong optical port is why my HMS had gone into a setting I have only very rarely used?
It was certainly NOT anything I had voluntarily initiated.

To me the difference between 1 M taps and the others is VERY OBVIOUS and not subtle.

I would not even have bought my Qutest if I had not heard it also with 1 M taps via BLU2 and knowing that the HMS was around the corner.

And a scientific logical approach to things ALWAYS has to include an open mind and the ability to adapt to new facts.
Every other mindset is not scientific imho.
Cheers CC

 

[Mikey99]

As someone who incorrectly re-cabled their set up, and listened to an MScaler in single-BNC mode for a day; I can vouch for the fact that I knew something was not-as-good-as-it-should-be without the Mscaler doing it's thing

Indeed, I had exactly this experience as well.

 

[rkt31]

Sometimes settings get changed after powering on. I think it happens when m scaler is not in use for longer time. It's normal i think.

 

[Christer]

Sometimes settings get changed after powering on. I think it happens when m scaler is not in use for longer time. It's normal i think.

Normal?
In this case I had just turned off and re-connected both Qutest and HMS to shift cables a few minutes earlier.
And the purple optical light that both went on of is own once and was lit while playing via usb one day, should I consider those normal too?
To me it seems more like some erratic behaviour, reminding me a bit of when my neighbour's dog steals the cat's food and gets told off for doing so.
I'll Keep a close eye both on that cute but naugthy little dog and the lights of my HMS from now on!

Cheers CC

 

[ZappaMan]

I have had many cases now where I was listening without realizing the m-scaler was in single BNC or pass through and quickly realized something was wrong. I have also done listening where I changed the mode without looking and had no problem identifying if it was in dual BNC or not. While not rigorous ABX, close enough. The difference is obvious.

Agreed single bnc mode is very flat, you know straight away something is wrong

 

[analogmusic]

Normal?
In this case I had just turned off and re-connected both Qutest and HMS to shift cables a few minutes earlier.
And the purple optical light that both went on of is own once and was lit while playing via usb one day, should I consider those normal too?
To me it seems more like some erratic behaviour, reminding me a bit of when my neighbour's dog steals the cat's food and gets told off for doing so.
I'll Keep a close eye both on that cute but naugthy little dog and the lights of my HMS from now on!

Cheers CC

Man goes to store
Complains that his tv switches off after 4 hours
Explains to store manager that his dog stole his cats food and his tv switches off afterwards

The store manager Just politely asks the man to leave the store.

On his way home the man realizes that the tv timer off is the culprit

He laughs a lot but is still unaware of how he is perceived on head fi.

 

[Christer]

Man goes to store
Complains that his tv switches off after 4 hours
Explains to store manager that his dog stole his cats food and his tv switches off afterwards

The store manager Just politely asks the man to leave the store.

On his way home the man realizes that the tv timer off is the culprit

He laughs a lot but is still unaware of how he is perceived on head fi.

And I just checked the colour red on the online manual of HMS and it is bypass.
Naughty little dog!

 

[analogmusic]

Someday Christer hopefully you will learn that less is more.

 

[dmance]

Regarding MScaler bypass. I've spent quite a bit of time looking at the digital outputs of MScaler using an Audio Precision APx525. What is certain is that the USB input vs the Toslink (or coax) input produces different outputs from MScaler. For example, a standard 1khz sine wave test tone encoded to SPDIF or PCM, input to MScaler, output via Toslink and decoded by the APx and FFT'd should show a single spike at 1khz in the midst of noise floor. Well this is the case for SPDIF on Toslink or Coax ...but is not the case for USB PCM ...which instead reveals many small jitter spikes from 10k outwards. What this means is that bypass through MScaler using USB is adding energy outside the pure sine wave frequency of the input test tone. Those small spikes are likely the skew in timing from USB->SPDIF clocks inside MScaler causing occasional sample errors (the logic picks the sample to the left or right). The character of these jitter spikes changes as test tones of 44.1, 48 or 96khz are used. When I use a XMOS U8 based USB->SPDIF converter adapter to pass the same test tones directly to MScaler as SPDIF->SPDIF I don't see any errors ...as you would expect since the input & output clocks are the same. So something about the XMOS clock implementation avoids this jitter issue but it is definitely there on MScaler bypass (and upsampling too).

Very likely this issue is not audible for many users ...however my work at AudioWise is to pursue end-game transparency and hence I am now using only SPDIF input into MScaler.

 

[Christer]

Someday Christer hopefully you will learn that less is more.

And I am just back from a trip to town,sorry not Harrods this time, but one of the local thrift shops where I bought yet another ten classical music cds at real bargain price.

If you or anyone else would've have asked me about buying cds two years ago, before I had heard BLU2 I would have answered, cds? No I don't buy cds.

But now I do. And I blame the same black naughty little thing called HMS that played a trick on me recently and which from now on I'll have to keep an eye on, not the naughty dog who ate the cat food.
Comprende? Capisce? Comprix? Verstanden? Got it?

One of the 8 cds I bought last week was actually a copy of the first classical cd I heard via BLU2 in Singapore two years ago which opened my ears to the hidden potential of a format I had basically written off as harsh and unmusical.

It turned out I was wrong and wow how happy I am about that.

And best of all via the after market BNC cables I am testing, that recording and many others sound very nice indeed.

But only good enough for me on white ie full 1M taps.

I like the colour red, red flowers and red wine for example.
But red will also be a warning sign for me with HMS from now on.

Very interesting to read dmance's follow up post about optical versus usb and HMS, measurement wise.

I am always interested to learn and read posts that possibly could explain and provide measurable reasons for my own experiences SQ wise.
Regarding usb and computer audio I have repeatedly asked here why it is still used so much?
Absolutely nobody I know in the Classical Pro Recording Business uses usb.

Your cryptic posts and way of reasoning on the other hand, often elude me dear analogmusic.
This time too I am afraid.
PS The problem was not that it switches off automatically after a while but the fact that when unplugged it sometimes starts up in a different mode and setting than it was in just minutes before.
And in a setting I have no use for at all.
I did not buy my HMS to use it in bypass mode.

Cheers CC

 

[AndrewOld]

Regarding MScaler bypass. I've spent quite a bit of time looking at the digital outputs of MScaler using an Audio Precision APx525. What is certain is that the USB input vs the Toslink (or coax) input produces different outputs from MScaler. For example, a standard 1khz sine wave test tone encoded to SPDIF or PCM, input to MScaler, output via Toslink and decoded by the APx and FFT'd should show a single spike at 1khz in the midst of noise floor. Well this is the case for SPDIF on Toslink or Coax ...but is not the case for USB PCM ...which instead reveals many small jitter spikes from 10k outwards. What this means is that bypass through MScaler using USB is adding energy outside the pure sine wave frequency of the input test tone. Those small spikes are likely the skew in timing from USB->SPDIF clocks inside MScaler causing occasional sample errors (the logic picks the sample to the left or right). The character of these jitter spikes changes as test tones of 44.1, 48 or 96khz are used. When I use a XMOS U8 based USB->SPDIF converter adapter to pass the same test tones directly to MScaler as SPDIF->SPDIF I don't see any errors ...as you would expect since the input & output clocks are the same. So something about the XMOS clock implementation avoids this jitter issue but it is definitely there on MScaler bypass (and upsampling too).

Very likely this issue is not audible for many users ...however my work at AudioWise is to pursue end-game transparency and hence I am now using only SPDIF input into MScaler. And I think i've read that Rob himself says MScaler sounds best with Toslink.

Can you please publish your graphs, and details of your test set-up.

And can you please link to where Rob says that M Scaler sounds better with toslink. Afair he said it makes no difference. For example here he says he can “hear no consistent change from using USB or optical“.

https://www.head-fi.org/threads/hug...official-thread.885042/page-430#post-14884368

 

[Uncle Monty]

Rob told me he struggled to get USB to sound as good as optical.

 

[dmance]

Can you please publish your graphs, and details of your test set-up.

Andrew as below.
Source is JRiver 24 on a Lenovo Windows 10 laptop. JRiver creates sine wave calibration files at 64-bit resolution and then dithers them down to 24-bit WAV files at 96khz sample rate - I set dither to TPDF.
My USB->SPDIF converter is this.
Audio Precision APx525 (Series A) Version 4.5 Software
Signal path for image#1: LAPTOP->USB->TOSLINK->HMS->TOSLINK ->APX (Input to Digital Optical)
Signal path for image#2: LAPTOP->USB->HMS->TOSLINK->APX (Input to Digital Optical)
FFT is 96k sample length, AP-EQUIRIPPLE Window and with 8 sample averaging
HMS was set to red (bypass mode)