Watts Up...?
Mar 5, 2023 at 11:29 PM Post #3,871 of 4,753
Regarding the -300dB value, it is just a catchphrase used to mock RW.
Most people who do it, already know he never said -300dB was audible (rest just ignorant ), but it has been a convenient excuse .
I remember there were similar school-yard mocking going on a while ago, when some ignorant people were saying that RW's claim that the 104.25MHz crystal used in Chord DACs can not be an integer of 44.1 and 48 , so they stooped to mocking the quote.
After I set them straight (of course with RW's input) suddenly the thread went dead.
Some school boys, never grow up.
These are 2 slides from very CanJam recent talk.

It literally says there is audible depth improvement in listening tests going beyond -220dB and -300dB noise shaping

And literally says distortion at -150dB is audible

I enjoy my Hugo2, but probably because the discrete D to A conversion and headphone amplification is done really well... But so are other DACs and amps I have, some discrete design, some with state of the art off the shelf chips

In fact, Hugo2 and Dave have average low voltage level output for IEMs - you can actually hear hiss, something you can't hear with my Topping A90 Discrete amp.

This one would be easy to pick in a blind test... hiss versus no hiss...


Slide28.JPG



Slide30.JPG
 
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Mar 6, 2023 at 4:19 AM Post #3,872 of 4,753
It literally says there is audible depth improvement in listening tests going beyond -220dB and -300dB noise shaping
Isn’t he talking about the noise shaping rather than the level listened at?

I wouldn’t be surprised if improving things that are not audible gives cues to the brain to fill in certain gaps, hence improvements in depth, etc. The way the brain works, I wouldn’t be surprised if we can hear things that are not audible, if you define ‘hear’ as what the brain ends up producing for our delight.

I still remember being amazed when I first heard instruments significantly further out on the soundstage despite no change in source, track, seating or speaker position. Witchcraft…
 
Mar 6, 2023 at 5:25 AM Post #3,874 of 4,753
Isn’t he talking about the noise shaping rather than the level listened at?
Yes, he is talking about noise shaper performance.
I am not here to debate whether RW is correct in his claims, I am not that knowledgeable.
But what he is saying, to the limit of my understanding, is that when small signals approach the noise floor performance of noise shapers, their amplitude changes. The DAC looses linearity and/or resolution, it could be -80db or so (just a guess figure). If the noise shaper performance is increased from -100db to -200db, then the small signals are no longer near the noise floor of the noise shaper, linearity and resolution of small signals improves as a result.
Depth perception, relies on small signal linearity and resolution, improve one, and the other improves with it.
There are many aspects that are out of band, but affects in band performance. RFI is one. Not related to the above, but think about it, why should one worry about RFI? it is obviously waaay out of the range of audibility! even bats can not hear MHz and above, so why bother with RFI filtering, or galvanic isolation? Should we heckle designers who implement them?
 
Mar 6, 2023 at 5:46 AM Post #3,875 of 4,753
Yep I also wrote that it is about noise shaping - still it doesn't change my question.
My point was that I think those who ridicule simply read "listening tests going beyond -220dB and -300dB" and (deliberately) misinterpret what was said.

I'm not sure what your question was.
 
Mar 6, 2023 at 5:48 AM Post #3,876 of 4,753
There are many aspects that are out of band, but affects in band performance. RFI is one. Not related to the above, but think about it, why should one worry about RFI? it is obviously waaay out of the range of audibility! even bats can not hear MHz and above, so why bother with RFI filtering, or galvanic isolation? Should we heckle designers who implement them?
Absolutely, and there are those who believe that anything that's 'inaudible' does not matter as you can't hear it...
 
Mar 6, 2023 at 10:29 AM Post #3,878 of 4,753
Why would anyone heckle designers who implement USB galvanic isolation?
This can show very obvious measurement improvement within audio band.
1678116365329.png

Do you even read the posts you reply to?
Or you just pick one small convenient clip, out of context, and just shoot off with it.

1678116572208.png


P.S Ignore button is my friend!
 
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Mar 8, 2023 at 4:49 PM Post #3,881 of 4,753
You can engage with head of KEF engineering on ASR

Genelec engineer is there too

Andrew Jones, Floyde Toole, Sean Olive also chime in over there

Bruno Putzey chimes in there too

Those are some of the best in the business in speaker design and understanding speaker performance in rooms - and Sean Olive headphones research

You just have to look and there is lots to learn from leading experts :wink:
The question was where are the other DAC designers?
 
Mar 8, 2023 at 7:18 PM Post #3,884 of 4,753
The noise shaper is a strange thing, creating a feedback-loop noise cancelling process that is similar to active noise cancelling may affect things that we have no clue of, fixing or drastically reducing quantization noise while keeping a simple switch scheme may do more than we know. Rob Watts running a noise shaper at over 100mhz at -300db is affecting depth, I heard it the minute I listened to his DACs, so there is something to this.
 
Mar 8, 2023 at 7:55 PM Post #3,885 of 4,753
That's 100% wrong. No one gets banned here for saying people can hear difference in DACs, or for citing science, or for pretty much anything except direct personal attacks.
Have you been in the Sound Science forum here? You try saying you can hear the difference between DACs and see what happens. You won't get banned, but you may wish you had if you answer back with some of the regulars. Mention cables and you may get tarred and feathered.
 

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