[Rob Watts]

So SPICE simulations can be very accurate - if your parameter data is detailed and accurate, and that is a big if! It is a modelling simulation, so unlike a Verilog digital simulation for the FPGA (which is 100% accurate), it will have some inaccuracies. But, if you are doing straight forward work, it is excellent - but the problems come with very high gain bandwidth, and with modelling parasitics (that is stray capacitances, inductances to the board and other components).

Discrete amplifiers are fine for simple stuff, but I had a complex, very high gain bandwidth circuit that worked in simulation but failed in practice due to parasitics. And that's where it's better to use op-amps rather than discrete components as the parasitics are defined and part of the operation of the design.

 

[thePhones]

Just want to let you know that the Nvidia Shield now has a new setting under advanced audio settings, don’t know how it’s called in english but it must be called something like “keep bit depth and sample rate”, which plays the content in it’s native quality as long as the used app can do it (Youtube can’t). This completely solved the problem with Netflix having huge variation in audio quality. I don’t know why because I expected it all to be the same (48khz with same bit depth). Maybe the shield converted everything to the same bit depth and “Better Call Saul“ for example just had the ”right“ sample rate to begin with because it always sounded outstanding. But now every show sounds good to me or at least lost it’s ”dull audio”.
But I did not stop there and bought a HDMI extractor (https://www.amazon.de/dp/B07TZRXKYG?psc=1&ref=ppx_yo2ov_dt_b_product_details) to get the optical directly out of the Shield and not over my Sony TV which still always keeps everything within 48khz. So now I can also play Qobuz (up to 96khz) over Airplay/Chromecast to the Shield and the M Scaler always shows the right sample rate (44.1 - 96khz). Since the TV does not have to be on for the HDMI extractor to work I can use the Shield as my main playback source now. Enjoy!

Quick update on the Youtube front. The solution to native Youtube audio sample rate (44.1) was changing the audio format to “mp4a” instead of “opus”. You can choose between those in the app Smart Tube (This app can do a lot of cool stuff). So I finally have Youtube on my TV with the full capability of the M Scaler. The quality of course varies as you will still have conversion degradation when the uploader uses 48khz

 

[FunkyBassMan]

Quick update on the Youtube front. The solution to native Youtube audio sample rate (44.1) was changing the audio format to “mp4a” instead of “opus”. You can choose between those in the app Smart Tube (This app can do a lot of cool stuff). So I finally have Youtube on my TV with the full capability of the M Scaler. The quality of course varies as you will still have conversion degradation when the uploader uses 48khz

How do you change the audio playback format to mp4a when playing back on the web browser?

 

[thePhones]

How do you change the audio playback format to mp4a when playing back on the web browser?

I only know this method by using the Smart Tube app. You can sideload the app via x-plore or another file manager

 

[Jawed]

@Rob Watts in this measurement of Mojo 2 from Golden Sound:

which is from this page:

https://goldensound.audio/2022/05/26/chord-mojo-2-measurements/

the noise shaper "shape" seems unusual. It rises to about 400KHz (384KHz?) and then it starts falling. Generally the shape of the noise from a noise shaper rises, only going up with frequency. We can see this behaviour in the measurement for DAVE:

Though, of course, it might be that the plot ends too early to be able to see a falling shape at some point.

So why is it that the shape of the noise versus frequency with Mojo 2 starts falling at the highest frequencies?

It is because Mojo only has WTA 1, so the noise shaper has been tuned to match WTA1 (maximum of 768KHz, noise falls from 8FS)? If that were true, in DAVE there would be a similar shape, where the noise starts falling at 128FS (about 6MHz)?

Maybe that means that the noise shaper itself has an upper limit on the frequencies it outputs, causing the shape seen with Mojo 2?

 

[Rob Watts]

Mojo 2 is a 4e pulse array, and in order to have low distortion levels, the noise shaper runs at a slower rate - hence why the noise starts rising around 100k. The noise falls at 400k due to the analogue filters attenuating the noise shaper out of band noise.

 

[LisaShayBrown]

Hey, sorry if this is a dumb question. but it's a serious one.


Does a DAVE/Scaler sound better after a warm-up period? When I first turned mine on today, I was like "this is good but I'm not blown away", but after maybe an hour it's sounding so amazing I can't walk away. I don't know if the difference is in my imagination?

 

[Somafunk]

Why not consider that your ears and auditory recognition takes a certain time to relax and adjust to listening?

 

[Mediahound]

Does a DAVE/Scaler sound better after a warm-up period? When I first turned mine on today, I was like "this is good but I'm not blown away", but after maybe an hour it's sounding so amazing I can't walk away. I don't know if the difference is in my imagination?

I believe he has stated he notices a slight improvement after 10 minutes of warm up.

 

[LisaShayBrown]

AA

I believe he has stated he notices a slight improvement after 10 minutes of warm up.

Thanks!

 

[jlbrach]

just leave it on standby....

 

[thePhones]

Rob, will you be at High End Munich in may and will you have a workshop there?
Maybe even about something that might have to do with more taps

 

[Kentajalli]

Rob, will you be at High End Munich in may and will you have a workshop there?
Maybe even about something that might have to do with more taps

Munich and more taps?!
Are we talking beer?

 

[Rob Watts]

Hey, sorry if this is a dumb question. but it's a serious one.


Does a DAVE/Scaler sound better after a warm-up period? When I first turned mine on today, I was like "this is good but I'm not blown away", but after maybe an hour it's sounding so amazing I can't walk away. I don't know if the difference is in my imagination?

I don't know about Dave as I always keep it on. But I can't say I have noticed a change when it's been off though. But when I use Hugo 2 on a plane, it takes about 10 minutes to warm up - the sound gets smoother with a bit better depth. I have been puzzled whether it's down to the pressure change affecting my ears (and perhaps the headphones) as I start my gear as soon as the seatbelt sign goes off, or whether it's M scaler/Hugo 2. Since I am in my hotel room waiting for CanJam NYC to start I thought I would turn it on and see - and so I played a track from cold, listened to some music, then went back to the first track after half an hour. I could not hear a significant difference on my opening track - so the 10 minute warm up is more about my ears/headphone adjusting to the pressure difference with the plane at cruising altitude.

Incidently, I played some Max Richter tracks I was listening too on the flight over to New York - and they sound significantly leaner at the 7,000 feet cruising altitude air pressure. Back at sea level, bass is more extended and fuller. This is something I had long suspected and it's not surprising as pressure changes affect sound - lower pressure reduces volume, and reduces the speed of sound.

Rob, will you be at High End Munich in may and will you have a workshop there?
Maybe even about something that might have to do with more taps

Probably not Munich this year. Next show I will be attending is Singapore CanJam, perhaps Chicago CanJam again, and I will be able to do London CanJam in August this year.

Munich and more taps?!
Are we talking beer?

Absolutely - and the more taps the better!

 

[Rob Watts]

Here is my seminar from NYC Canjam on DAC types. I have gone into more detail about differing DAC topologies.