John Curl's Blowtorch preamplifier part II

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signal to noise on the line to the amps by lowering the gain amp you run a much hotter signal improving the snr and reducing the problem of hum and emf problem by uping the line voltage to 10 volts or more rather than less than 1 volt . As well as line loss becomes less of a problem .

DAC outputs same level whether in pro gear or domestic. Feed to speakers is same level unless there is a significant spl or efficiency difference. So if the total gain is the same I can't see a snr improvement. Running interconnects hot may have some theoretical benefits, but if you run balanced in the home you can get a noise free digital playback system to any sane measure.
 
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Don't believe I had the pleasure, we did Belgian (semi) automatic shooting fries in my days. I do have really nice bullet hole and knife scars though.

Then again, you wouldn't believe the places I've seen with ear protection.
I've worn ear protection for years on end in various jobs, everything from simple foam plugs to fancy adjustable valve ones.
Machine shops as Mr Soibelman, ship yards, navy frigate and submarine engine rooms.

Even a stint as a quality controller in a glass bottle factory, called a matman, who walks up to the mould man to tell him it's time to exchange/clean a mould.
While both are wearing ear protection, you wouldn't believe the noise and heat level at the moulding position.
Likely the reason my hearing isn't half bad at my current age.

It's been my experience that hearing human voices isn't that hard while wearing ear protection.
Takes a little practice maybe, like shooting.

yep. You and a zillion others have protected their hearing when they had the hearing protectors to use. Zillions in the militay dont use them and are thus loosing their hearing at an early age.


THx-RNMarsh
 
Any combinations of methods might allow sufficient quality to get convincing sound - there is no exclusive, "right way". The key thing to be aware of, is that for any recording that you have satisfying playback can be achieved if enough effort goes into creating a sufficiently well behaved, electrical replay chain ...
 
Don't forget the earlier experiment showing how vision effects how or what we hear. When you are wearing hearing protection you can see the other persons mouth movements and this may have much to do with the fact we can still understand what someone is saying even with very high attenuation hard shell hearing protection?
 
signal to noise on the line to the amps by lowering the gain amp you run a much hotter signal improving the snr and reducing the problem of hum and emf problem by uping the line voltage to 10 volts or more rather than less than 1 volt . As well as line loss becomes less of a problem .

At the expense of increased distortion in the line stage and increased NFB in power amp, all else being equal.
There is no such thing as a free lunch ;)
 
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I understand fas42 and agree -- do what you can with what you have, is another good idea. I am going for the highst of HiEnd, though. Why? Because I hear a big gap still between live acoustic sounds and recorded/playback. And, I learned that digital can be better than it is and it started with 24/96K and HD downloads for me to know digital can be better than it has been. So, while I share your idea and do it also to what ever i have.... get the most out of it.... the potential has not been realised from what I hear and measure with 16b/44.1K. Now JC is also interested in only the HiEnd mostly and what it takes in analog is more than one would think to push it further. Same Same with digital.


THx-RNMarsh
 
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At the expense of increased distortion in the line stage and increased NFB in power amp, all else being equal.
There is no such thing as a free lunch ;)

Maybe. Maybe not. I think it can be done... if it hasnt already. Without increased distortion (that anyone could hear).
Not that it is easy, however. But do-able with the right people.


THx-RNMarsh
 
The interesting aspect, for me, is that I know I haven't achieved, heard the full potential of many of my CD recordings - I focus on total "listenability", that the sound just captures you and takes you away into the space that the musicians inhabited when making the recording - but I have also heard some "technical" quality being superior in another system, even though the listenability wasn't so great in some aspects. An example being, the 'purity' of a Spanish guitar's single note hanging in the air.

So, plenty of space to explore still ...
 
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But as I said you can wear hearing protection and still hear someone talking to you even at the gun range with crazies shooting there 50 caliber hand guns, really mini cannons.

I own two over the ear and several in ear plugs. I can hear people talk also.

You cant get much more than about 30dB atten because of bone conduction/bypassing the ear canal and thru the Eustachian tube to the ear. It will knock that 140dB impulsive .223 cal. sound blast to a level which is still not the healthiest on a repeated basis.

I had a SLM with me to get the high level at Carnegie.....that little bell was at a musical pause so it was the only sound at that moment. The level was too low to register on the SLM (<30) .... All-in-All, an easy 105dB dynamic range change was played that night, I estimated. If I had a recorder, I would want at least that much range for that particular performance. I can get that range in my home (22dB noise floor). The recording electronics etal would have to be better than that range to prevent peak clipping.

And, I mean not 90dB dithering away little sounds, like a small bell a hundred feet away in a large space. That music performance dynamic range I heard is withOut dither. And, to hear that bell as clearly as in live performance, will mean a lot more bits down low in level.


THx-RNMarsh
 
Okay, folks - that "undone" version of Californication is here, https://www.dropbox.com/s/i5vwb73drisct1c/Californ.wav?dl=0 - sequence is original, then fiddled, repeated 3 times.

Caveats: a relatively big WAV file, so could do single sequence, convert to FLAC, still big though ... original is an MP3 source, I don't have the album, so don't get hung up on those quality issues ... this was an early exercise, probably could have been tuned a bit more - but gives one an idea ...

The first 30 seconds is awful noise with pieces of music in the background. Then 30 seconds of music. Then 30 seconds of awful noise again. I didn't check the remaining seconds. I downloaded it twice to make sure the file wasn't corrupted.
 
Richard, a little bell sound like that is not a problem for 16 bits, I have a number of classical recordings that have that type of content, and it is beautifully conveyed - that quality of tome you speak of is fully there.

I have some ambient recordings here, which would challenge the title for the most laid back, "insipid" recordings one can find - "crystal shop" type of background music. But, wind the volume right up, to near maximum - and way, way in the distance you can hear little things happening - tiny, quite intricate sound escapades occurring, percussive miniatures. 99.9% of listeners would completely miss these happening, they would be inaudible.

Appears musicians can't stop themselves, they will always add little Easter Eggs of sound if they feel that the required content is too boring, just to amuse themselves ... ;)
 
The first 30 seconds is awful noise with pieces of music in the background. Then 30 seconds of music. Then 30 seconds of awful noise again. I didn't check the remaining seconds. I downloaded it twice to make sure the file wasn't corrupted.
Keantoken, thanks for the feedback, and my apologies!!! Yes, badly corrupted - comes from a burnt CD, and it played perfectly correctly from there; so ripped to my hard drive and uploaded from there. The ripping software seems to have done something very bizarre, performed an inverted sort of clipping; I've never experienced this before, so didn't check the rip! The download is gone - so I'll go through the whole exercise again, and double check, before posting a new link!

Sorry about that ... :eek: :eek: :eek:
 
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