John Curl's Blowtorch preamplifier part II

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OK, so in the dither article it says
Inside a digital mixing console (or workstation), the mix buss must be much longer than 16 bits, because adding two (or more) 16-bit samples together and multiplying by a coefficient (the level of the master fader is one such coefficient) can result in a 32-bit (or larger) sample, with every little bit significant.

Now unless he is adding 70dB of gain or I am being very dense I can't understand what he is saying here, unless he is assuming the next step from 16bit integer is 32 bit integer.
 

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You misunderstand my position... I am looking for an explanation why for all these years i have had CD's and players.... they have never sounded as good as the HD 24/96 downloads. So far, you have shot down every possibility but not explained this difference i and so many others have experienced. maybe you dont know either. So, I'll end the questions about could it be this or that? My conclusion is that the masters are better than the 16 versions on CD but still dont know why.

I said I purchased and heard the difference of the PONO vs BenchMark2 before i saw the data on the PONO in this months issue of Stereophile-- which to me explains what i heard. It sounded like 2nd and it measured that way. SE tubes circuits have that affect on me also when they have high enough 2nd's. They sound thicker. I can enjoy the music though. But it isnt as accurate as it could be. I dont care if it open loop or not, as long as the distortion cant be characterized so easily upon hearing. There is one person on another forum who has developed a low enough thd (<-100db) with no gnfb and i am sure I would like it as well as any high gnfb design. I am waiting to get his sample to test and listen to soon. Once the distortion is low 'enough' for me, it doesnt matter what the topology or analog or digital or what ever.... un detectable is undetectable.
The negative spin --- doubts. Because, I still wonder why CD I have heard for so long do not sound as good as the HD downloads and offered some possible areas in hope that someone could explain it to me.... no such luck. But so what. I can get low enough distortion now in digital as well as analog and I am happy with that.

Thx-RNMarsh

Expectation bias?

Simple a-b experiment that requires a track that you own both an older 16/44 and a remastered 24/96. Preferably, pick a piece that you're not as intimate with, and ideally use a 1-2 minute section in the middle (matched exactly), so you'll be less likely to determine which is which from non-playback reasons. Use EAC to pull the lower res file off a CD and on to your computer if it's not already there.

You should have 4 files (use SOX, SoX - Sound eXchange | HomePage for consistency):
1.) Raw 16/44 file
2.) Raw 24/96 file
3.) Upsampled older 16/44 peice to 24/96
4.) Downsampled and dithered 24/96 to 16/44.

* Each track needs to be normalized volume-wise as well--pin it to the levels on your newer 24/96. This can be done within SOX.

ABX on 5 useful tests:
1.) File 1 vs File 2
2.) File 1 vs File 3
3.) File 1 vs File 4
4.) File 2 vs File 3
5.) File 2 vs File 4

No peaking. Use your Benchmark DAC and your favorite headphones. Post the results.

Remember, no peaking.
 
Amusing you went from this

Of course all the other electronics in the world with high precision DACs, ADCs sensitive analogue seem to work fine with SMPS supplies... Even in headphone shells powering the electronics...

to this

There does seem to be a move these days for more distributed power, with a main supply feeding many on board local supplies, SMPS for the high current demands such as processor cores, I/O supplies, further sensitive circuitry having further power islands' fed from LDO's.

in successive posts, ;) ...
 
You misunderstand my position... I am looking for an explanation why for all these years i have had CD's and players.... they have never sounded as good as the HD 24/96 downloads. So far, you have shot down every possibility but not explained this difference i and so many others have experienced. maybe you dont know either. So, I'll end the questions about could it be this or that? My conclusion is that the masters are better than the 16 versions on CD but still dont know why.
And you've been told over and over again what the answer is - insufficient engineering of every aspect of the system.

This is like a person who complains that his swimming pool always keeps dropping in level - he puts fancy, expensive covering over it to stop evaporation, high fences around so the wind doesn't make things worse, special additives in the water which supposedly "condition" it so this doesn't happen - yet the problem remains - someone idly comes along, looks down and says, "I see a small hole in the liner over in the corner there - maybe that should be checked out" ... "Nahhh", says the owner, "That sort of thing is not important enough to be a problem!!"
 
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he is talking about the multiplies that you require when you add effects or filter etc.
That's not what he said then. He just proffered master gain which could be assumed to be a +/- some small number of dBs. If he wanted to say that a 16 bit by 16bit DSP MAC can result in a 32 bit intermediate he should have said so? He doesn't name names but I surely no professional workstation software would get the maths that wrong in this day and age? User error of course will always screw up the result...
 
To be Frank ;) If you cant get 16 bit audio to sound good, you wont get 32 bit sounding better. I like a simplified approach to complex issues but only if it's accurate, here's an article which manages that quite well (as far as i can tell).

Tweakheadz 16 Bit vs. 24 Bit Audio
Nice one, Davy - I'd go along with the article, it's on the money.

I like the bit about "voodoo", ;) ... "normal" CD sound is often a bit throwaway, and people want a magical reason for that being so - wave a magic wand and it all gets better, :). Sorry, it's just hard work, attention to detail that's required - but that means you have to get off your bum, and think a bit more about things ... bugger!!! :D

This,

People ask me all the time, and I wince every time they do: "What gear (fill in the blank...soundcard, preamp, cable, recorder, sequencer) will give me the "best" sound quality?" I wince because I imagine the person going out, buying a $500 preamp and the stick it in their studio and connect the Mic and crestfallenly realize it "sounds the same" "maybe a little better" um, "hard to tell". Why the heck is that? The main reason is that it is all a big system and it is only as pure as its dirtiest pan pot. One humming cable can obliterate the gains made by otherwise great sounding gear. A pristine Mic preamp connected digitally to a soundcard with the jitters will be defeated. Your whole chain has to pro quality, from preamps, in and out of the converters, into top quality monitors. But if you do have a great signal chain, even your 16 bit recordings will sound better than 24/96 with average preamps and typical converters and monitors.

nails it ... worry about everything, and then it all falls into place - including on the replay side!! Simple to say, but so many don't get it ...
 
Cheers Frank. I first read that a while ago but it seems appropriate to this thread.

While i'm typing i've got this on the hifi - http://www.amazon.co.uk/dp/B000092A...rd_t=201&pf_rd_p=569136327&pf_rd_i=B0000793ZD

I bought it on CD back in 1989 when it came out, i've not played it in years but i dug it out and ripped it to FLAC (16/44.1) earlier today. I am amazed at how it sounds through my present system, i wish you could hear this set up Frank.
 
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No prob's, Davy ... I do "get" it - I don't know the material at all, I just listened to the YouTube clip on my crappy laptop sound - but I know exactly how it should sound on a well sorted out system - big, big, deep sound, that fills vast spaces ...

The interesting thing is that after one goes a reasonable number of rounds, with optimising, listening to a huge variety of types of recordings, at various stages of tune of a setup - that one can tell what the potential of an unknown recording is, even on a pretty poor playback system - there are various clues, signature attributes that still come through. You know how well the recording can come across, and so you keep working at things until that level of replay is achieved ...
 
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No prob's, Davy ... I do "get" it - I don't know the material at all, I just listened to the YouTube clip on my crappy laptop sound - but I know exactly how it should sound on a well sorted out system - big, big, deep sound, that fills vast spaces ...

Bang on the money Frank! The sound seems to be trying to envelop the whole house, it's an experience for sure.
 
Christophe,
I am still sitting on the sidelines waiting for ssd technology to mature and for some of the problems with life expectancy to be improved and the price of larger drives to come down. I also have 10,000rpm drives in my laptop and 6gb of ram with an i5 processor. I do need a faster machine now that I am again doing mostly design work on my computer, I especially was reminded of that the other day having to do some rendering of some cad files, what a waste of time that was but something that I have to do. It reminds me of my original Compaq computer with a 20mb hard drive and getting a new scanner, one scan and the entire hard drive was full!

Reliability is getting awfully good, especially if you're a bleeding edge kind of guy that will likely be relegating older toys to lesser-used systems on a decent schedule.

The SSD Endurance Experiment: They're all dead - The Tech Report - Page 1
 
A bit demanding with amplification, since they are more like 6 ohms rather than 8. I use mine with a LM3886 diy, i´m not sure if the LM3875 would drive them properly. The speakers are musical and can provide good of enjoyment of the music, perhaps this is the most important factor. Surprising bass for the size.
 
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