John Curl's Blowtorch preamplifier part II

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Ah, we're all doomed! Those poor fools, listening to LP's, convincing themselves that the atrocious sound is vaguely worth listening to are in the same boat - if they could only see the measurements that point out how dreadful the technical performances of their beloved cartridges are, then they could dispense with this absurd delusion that they are listening to something worth hearing ... ;)
 
Just pointing out, John, that there's distortion, and then there's distortion. Of course vinyl playback can create magic sound, I've heard this on many occasions; just, no matter how "hopeless" something is in some technical areas, like the 741 chip, or a cartridge, if enough of everything else works well enough then a very satisfying listening experience can still result.

I believe that audio playback is capable of truly astounding sound if the system works sufficiently well; from my POV, not enough care is usually taken with the seemingly less important aspects, which is what cripples the potential much of the time ...
 
listening to LP's,



just bought a mid-fi turntable at goodwill last week.

had the cartridge, and the needle.

less than $15us.

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random pic section -

sssssun bathing neighbor,

and

smoke from the so called 'spring fire' -
 

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John, the problem is that what the ears are picking up, but what conventional measurements are not, needs to be quantified, converted to a standardised testing regime.

The problem here is that what people report is not what their ears pick up, but what they perceive. It's not difficult to measure what the ears pick up, but what then happens with that signal until at some point the listeners says 'I hear...' is such a convoluted, unreliable and constantly changing process that it is almost impossible to make sense of it.

Compare it to looking at a painting. What the eyes pick up are maybe millions of various colored pixels, and after the processing in the head this leads to 'I like it...'.
Funny enough, the guy next to you, picking up the very same pixels, says 'It's too green for my taste...'. Go figure.

jan
 
Well, what I hear in a lot of replay is a type of distortion which is unpleasant, offputting or at least dulls or deadens the sound. I'm certain this can be measured by some of more considered methods put forward, by many people, but so far this hasn't been done, as far as I can see ..
 
presumably the faceless fortune 500 audio corporations and lazy, boring, deaf, artless, clueless engineers will stop drooling long enough to stumble upon a proper test regime for vaguely described non-issues and hundreds of solutions to all those problems that have been staring them in the face, will simply fall out of the sky...
 
Something like that ... :D

The key word there was "non-issues" - most people with access to the resources needed to do the job don't believe anything needs to be done, so why should they bother themselves ...

In other words, the sound quality in the clip I mentioned just before is "as good as it gets" ...
 
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Well, what I hear in a lot of replay is a type of distortion which is unpleasant, offputting or at least dulls or deadens the sound. I'm certain this can be measured by some of more considered methods put forward, by many people, but so far this hasn't been done, as far as I can see ..

I have a reasonably well equipped lab, but I have no idea how to measure 'unpleasant, offputting or at least dulls or deadens the sound'. I even have no idea whether the effect is heard by others, or whether it is just your personal perception.
But I'd be happy to send you my hourly rates ;)

jan
 
Compare it to looking at a painting. What the eyes pick up are maybe millions of various colored pixels, and after the processing in the head this leads to 'I like it...'.
Funny enough, the guy next to you, picking up the very same pixels, says 'It's too green for my taste...'. Go figure.

jan

Sorry for OT, but I wonder if in about 20-30 years, we are going to see that this assembling process that our brains are going through with HiDef TV's is having a detrimental effect. I have read a few articles here and there that suggest that this new style of viewing is a great deal more taxing on the visual part of our brains than the "analogue" of old. This is especially true when compared to our daily view, the real world. Wonder if the ear is as sensitive to these micro pixels, as the eye. Of course many will say that it is a ridiculious notion that digital audio is the different, but i look at it like the TV. It is still an assembled group of blocks. BTW, I rarely listen to vinyl, not setup for it, but moving that way, for some reason.
 
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Well, I don't know, I remember that half a century ago the same was said about the then emerging TV. That it would damage our brain because it was such a bad picture, resolution-wise. One thing I know - it's much easier to read a hi-res pdf than a roughly scanned jpg, and it's much easier to talk to the guy next to me than through a distorting cell phone connection.
But time will tell I guess.

jan
 
thats ridiculous, the day you accurately describe an issue instead of just arbitrary words that are so general as to be meaningless and give no hint whatsoever about where to look, i'm sure someone will do something about it. until then, despite your years of studying such phenomena, by playing the most horrid badly produced music you can find to hilight said issues, instead of listening to music you enjoy, it remains a non-issue.

Given your claims of how clear it is, i'm surprized you dont have any idea what the cause is ... :confused: it seems youve spent a great deal of time examining somewhat random collections of equipment to get to the bottom of it, yet have come up empty-handed. how do you expect someone to be interested enough to spend money on it?

Something like that ... :D

The key word there was "non-issues" - most people with access to the resources needed to do the job don't believe anything needs to be done, so why should they bother themselves ...

In other words, the sound quality in the clip I mentioned just before is "as good as it gets" ...
 
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I have a reasonably well equipped lab, but I have no idea how to measure 'unpleasant, offputting or at least dulls or deadens the sound'. I even have no idea whether the effect is heard by others, or whether it is just your personal perception.
But I'd be happy to send you my hourly rates ;)

jan
As a favour to a good buddy, you could do it like this, one of a myriad of a number of ideas, ;): create test tracks, of say firstly just two high audio frequencies at medium volume, there will be some IMD; then in successive versions keep those two signals static and mix in successively higher levels of, say, a couple of bass frequencies carefully chosen so no IMD products clash with the those resulting from the two high frequency tones alone; right up to maximum possible levels of the bass notes.

Then, in testing, all you monitor are those high frequency IMD frequencies. This is testing how capable the amplifier is in sustaining the high frequency distortion performance, as the power supply and output stages are placed under greater and greater stress.

No invoices, no pack-drill ... :D
 
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