Digital Audio and Amplifier Noise Floor Comparison - Is 16bit/44.1kHz All We Need ???

[Rt66indierock]

9 minutes ago, Paul R said:

 

Where we disagree is that 16 bit noise floors are below the noise floor of most equipment. I think you are simply wrong there, 16bit is well above the noise floor for most equipment these days.  And of course 16bit noise shaping adds some peculiar distortions not present at all in 24bit.

 

 

Find me some amps with a S/N ratio of 96 dB at one watt of output. The quick and dirty method to estimate this is your numbers minus 20 dB. I don't think you will find many.

[Rt66indierock]

12 minutes ago, esldude said:

A-wtd is usually a 4-6 db improvement over no weighting.  So it isn't like unweighted results are suddenly terrible.  More common is fudging on real values or some trickery in gain staging that gives a number you won't see in normal use.  As Rt66indierock said, your noise floor is much closer to the signal at 1 watt levels.  Of course with common speakers you only need mid-80 db SNR to be so low it will never be heard at 1 watt.  Plus your SNR with dithered 16 bit is worse by a half bit to bit.  So rather pointless to engage in petty arguments without putting all this in context. 

 

I've found it interesting no one ever points out that with shaped dither and 16 bit audio there is a real benefit to high sample rates.  Here is where I took silence, and saved it in 16 bit with shaped dither in both 44/16 and 192/16.  I then filtered out everything above 20 khz in the 192 file.  Notice the shaped 44 has a noise level of -84 db while the filtered 192 is -120 db.  This is what would happen if your speakers (and your ears) don't respond above 20 khz.  Of course no one does 192 at 16 bit do they.  Getting back on topic, something like this could have been done with MQA without requiring licensing, messing with undecoded fidelity or causing other problems.  

 

 

In my defense, I'm going to keep using my Klipsch Heresy's at home so I need something quiet. John Siau of Benchmark recently wrote and made some graphs about how quiet your stuff has to be to hear certain bit depths. 

[Rt66indierock]

Just now, Paul R said:

 

I believe both the Benchmark and maybe the Outlaw monoblocks meet that criteria.

 

We know the Benchmark does, the Outlaw amps don't but they are great for vinyl. Reg Greene of TAS says the Bryston amps meet the criteria. I'm looking at a Canadian design that meets the criteria.

[Rt66indierock]

4 minutes ago, Paul R said:

 

Those are really efficient aren’t they? The IIIs are like 99db. Generally the more efficient the speaker, the quieter the electronics of course. 

 

My Heresy II's are spec'd at 96 dB. 

[Rt66indierock]

4 minutes ago, esldude said:

You do realize with most speakers being about 86 db for one watt you only need -86 db to get everything down to 0 db SPL when measuring at 1 watt.  When taking into account Fletcher-Munson you can probably have complete perceptual silence with even less.  I'm all for good performance, but the idea you need THD+N this low is a little over the top for 1 watt.  And for most good amps you really are going to being talking about N(oise).  

 

My Heresy II speakers are 96 dB so I need a little more.

[Rt66indierock]

9 minutes ago, Paul R said:

 

Those are measures of efficiency.  Your Heresy's only require roughly 1/10th the power to reach the same sound levels as a speaker with 86db efficiency. 

 

 

My Heresy's hiss a little with an amp that is quiet with the speakers in my office that are approximately 86 dB efficiency.