Hi rez and Solid State Noise

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werd

Hi rez and Solid State Noise
« on: 30 Oct 2010, 07:25 am »
With the big movement in  hi rez recording/down loads, when is solid State amplification going to catch up?. We see 192/24 recordings more available but we also see amplifiers at 110 db noise (and these are expensive amps). Here its only 18 bit resolution at best. Will we ever see 144db (24bit) noise floor out of a solid state amp?

Phil A

Re: Hi rez and Solid State Noise
« Reply #1 on: 30 Oct 2010, 01:27 pm »
Just a thought/question.  Given the average noise levels in a living room (i.e. http://www.consultnet.ie/occupational%20noise.htm) are we really going to hear all that difference or perhaps a fraction of it?  I'm not talking about an isolated chamber but a real world room.  I've seen people for example post about hi-rez in a car and wonder why given the limitations of the environment.

Speedskater

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Re: Hi rez and Solid State Noise
« Reply #2 on: 30 Oct 2010, 01:38 pm »
Many, many people are quite happy listening to vinyl LP records or magnetic analog tape both of which have a much, much higher noise floor.
Before you worry about a power amplifier noise floor, what about 192 kHz ADC's and DAC's noise floor.

werd

Re: Hi rez and Solid State Noise
« Reply #3 on: 30 Oct 2010, 04:11 pm »
Just a thought/question.  Given the average noise levels in a living room (i.e. http://www.consultnet.ie/occupational%20noise.htm) are we really going to hear all that difference or perhaps a fraction of it?  I'm not talking about an isolated chamber but a real world room.  I've seen people for example post about hi-rez in a car and wonder why given the limitations of the environment.

I wonder about that. We won't know until we get there. But i believe if we do hit noise floors in this range it will be noticeable. Air between instruments and leading/trailing edges will be remarkable.

timind

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Re: Hi rez and Solid State Noise
« Reply #4 on: 30 Oct 2010, 04:57 pm »
Many, many people are quite happy listening to vinyl LP records or magnetic analog tape both of which have a much, much higher noise floor.

My initial reaction also. A decent phono preamp has a s/n of 85db and many will swear by it's superiority over any digital source no matter the 20db difference in favor of the digital.

*Scotty*

Re: Hi rez and Solid State Noise
« Reply #5 on: 30 Oct 2010, 05:00 pm »
This isn't a problem. If you look at the recovered waveform of a 24 bit -90dB signal played back on the best of todays dacs most of them will barely do 20bit replay as far the noise floor is concerned.
That negative 24bit 90dB waveform is not reproduced  perfectly either,it has some distortion present
which you can see when you look at it. I am not sure that a 24 bit recording has better than 85dB of actual usable dynamic range. I define usable dynamic range as having lower than 3%THD at the lowest recorded signal level.
  More to the point your room's ambient noise floor is lucky to be 45dB. If you could add 85dB to that you would have a 130db peak SPL which is louder on peaks than even I want to listen at. The prevalence of compression in todays recordings assures that we won't even need the 85dB of dynamic range that 24bit might have.
Scotty
« Last Edit: 31 Oct 2010, 01:03 am by *Scotty* »

werd

Re: Hi rez and Solid State Noise
« Reply #6 on: 30 Oct 2010, 05:01 pm »
My initial reaction also. A decent phono preamp has a s/n of 85db and many will swear by it's superiority over any digital source no matter the 20db difference in favor of the digital.

You don't have to sell me on vinyl, i think at the moment,its the true hi rez format. But if we see over 120 db noise from solid state i think vinyl will start getting left behind.

werd

Re: Hi rez and Solid State Noise
« Reply #7 on: 30 Oct 2010, 05:05 pm »
This isn't a problem. If you look at the recovered waveform of a 24 bit -90dB signal played back on the best of todays dacs most of them will barely do 20bit replay as far the noise floor is concerned.
That negative 24bit 90dB waveform is not reproduced  perfectly either,it has some distortion present
which you can see when you look at it. I am not sure that a 24 bit recording has better than 85dB of actual usable dynamic range. I define usable dynamic range as having lower than 3%THD at the lowest recorded signal level.
  More to the point your room's ambient noise floor is lucky to be 45dB. If you add 85dB to that you have a 130db peak SPL which is louder on peaks than even I want to listen at. The prevalence of compression in todays recordings assures that we won't even need the 85dB of dynamic range that 24bit might have.
Scotty

I know but if we can 120db from an amp lets say. It would be safe to say that dac technology is getting it too.

*Scotty*

Re: Hi rez and Solid State Noise
« Reply #8 on: 30 Oct 2010, 05:48 pm »
werd,go read one the DAC reviews on the Stereophile website and check out the graphs in the measurement section showing the true noise floor of 24bit dacs as well as what the -90 waveform looks like and you will see that the -120 dB noise floor isn't usable.
Scotty

Letitroll98

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Re: Hi rez and Solid State Noise
« Reply #9 on: 30 Oct 2010, 06:10 pm »
I am no expert on hi rez or digital formats, but from a newb's perspective I thought that the reason for these hi rez bit rates was to raise the noise floor into the higher bit resolution area.  I know I'm not saying this precisely so please forgive the ignorance, but I hope you can sort it out, I mean get the music above the LSB so so microdynamics are resolved cleanly.  Hi bit rate is not intended to create 130 db of dynamic range, right?  Please feel free to correct my sloppy statements. 

werd

Re: Hi rez and Solid State Noise
« Reply #10 on: 30 Oct 2010, 08:12 pm »
werd,go read one the DAC reviews on the Stereophile website and check out the graphs in the measurement section showing the true noise floor of 24bit dacs as well as what the -90 waveform looks like and you will see that the -120 dB noise floor isn't usable.
Scotty

What about on 24/192 recordings?

Phil A

Re: Hi rez and Solid State Noise
« Reply #11 on: 30 Oct 2010, 08:32 pm »

*Scotty*

Re: Hi rez and Solid State Noise
« Reply #12 on: 30 Oct 2010, 09:49 pm »
Here is another link to graphs on Stereophile. Notice that even 16bit data has a noise floor lower than -105 at 20kHz. With the higher bitrate data even lower down. The noise floor is not the issue it is the rising harmonic distortion as the signal level gets lower and fewer bits are available to describe the waveform that is the problem.
  http://stereophile.com/hirezplayers/dcs_puccini_sacd_playback_system/index6.html
Scotty
« Last Edit: 31 Oct 2010, 01:06 am by *Scotty* »

werd

Re: Hi rez and Solid State Noise
« Reply #13 on: 1 Nov 2010, 03:31 am »
You see i am not convinced of these graphs proving anything other than what my orig OP was suggesting. The graphs show noise low with 96/24 (around 20 bit), I would assume 192 to be even better.  :dunno:. Amplification is at only 110db noise at best.

turkey

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Re: Hi rez and Solid State Noise
« Reply #14 on: 2 Nov 2010, 02:05 pm »
With the big movement in  hi rez recording/down loads, when is solid State amplification going to catch up?. We see 192/24 recordings more available but we also see amplifiers at 110 db noise (and these are expensive amps). Here its only 18 bit resolution at best. Will we ever see 144db (24bit) noise floor out of a solid state amp?

Do we _need_ to see 144 dB S/N in an amp?

Typical recordings and listening rooms don't even take full advantage of Redbook in terms of dynamic range and S/N.



martyo

Re: Hi rez and Solid State Noise
« Reply #15 on: 2 Nov 2010, 02:17 pm »
Of course we don't Turkey.

Mitsuman

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Re: Hi rez and Solid State Noise
« Reply #16 on: 2 Nov 2010, 11:08 pm »
Of course we don't Turkey.

We do if someone can convince you that we do and they think they can make a buck at it.  :lol: Sorry, I couldn't resist.

werd

Re: Hi rez and Solid State Noise
« Reply #17 on: 3 Nov 2010, 12:07 am »
Do we _need_ to see 144 dB S/N in an amp?

Typical recordings and listening rooms don't even take full advantage of Redbook in terms of dynamic range and S/N.

This has nothing to do with redbook, look at my op

*Scotty*

Re: Hi rez and Solid State Noise
« Reply #18 on: 3 Nov 2010, 12:22 am »
Halcro appears to have delivered this performance at least 5 years years ago, whether we needed or not.
Scotty

turkey

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Re: Hi rez and Solid State Noise
« Reply #19 on: 3 Nov 2010, 01:39 pm »
This has nothing to do with redbook, look at my op

My point was that Redbook allows for better dynamic range and S/N than we can actually use, so why spend more money on a 144 dB S/N? If you'd like to avoid mentioning Redbook, we could observe that many people are happy with the dynamic range and S/N that vinyl allows. (I'm not, which is why I use Redbook as my reference.)