John Curl's Blowtorch preamplifier part II

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The piano is both distorted and out of tune (oh those awfull harmonics !) to my ears.
So, i tend to prefer X, (More loaded, killing a little them, and bringing a little more body ?) (or less, allowing more dynamic on the fundamentals and not adding its owns ?)
I think Y is not loaded, but I need an other source to figure out what's from the recording and what's from the system.
Anyway, the difference is obvious.
btw: i listened throw a porta pro headphone just plugged in my computer: my hify is in a truck on the road to Portugal, not the good conditions.

There is audible distortion on the recording, on the leading edge of the piano... do you think that one vs the other handles that distortion differently ?

I tried with Foobar and doing an ABX and could fairly easily get 5/6 5/7 without to much effort and yet in absolute terms its hard to say one is obviously worse than the other.


You'll know soon enough.

Second try, i'm not so sure of the difference...
The time for *my* sound card to warm a little ?

:D

Its hard to concentrate on something so badly recorded, and sounding so disagreable, yes.
Mooly, if you are looking for a good piano jazz track, try, from Don Pullen album "Sacred Common Ground" -> "Common Ground".

If you can afford the sadness and the revolt of this pianist, improvising in the recording studio he was working in at this time, just back from the hospital where he was said that he had a cancer and few months left to live..

Thanks for the recommend. Jazz isn't really one of my favourite genres if I'm honest (although I have some Jacques Loussier that kicks things up a gear or two).

Its difficult finding short test tracks that are complete in themselves, which was one of the reasons I chose this one.
 
Yet 100% of the earths population likes music, sorry to say, but we have not done a very good job, Never has so many people listened to high-quality music through headphones, and yet we disappoint them badly when they enter at HiFi shop.
They listen to 30% of the content and still we fail to impress them with all our studidio XX-bits YYKHz recordings and 0.0000 to light of the stars amplifiers...!!

We really need to look in and be more critical in what we release to the streets.
 
Of course, audio is a 'niche' today, but look how it is still active around the world. Most of us have to do something else, and have audio as a hobby on the side, but so what? I was fortunate that I got my chance to make an 'all out' audio product, the Levinson JC-2, 40+ years ago. That is what gave me my start in home audio design. Before that I worked for military-industrial or the pro audio market. I was lucky, I guess, but it was not all just luck. I happened to design the circuits for an audio product that turned people toward it then, and it is still respectable today. It is true that hi fi has gone to be ultra expensive, with as much, or more, time and money invested in the 'fit and finish' in order to compete in the marketplace, and it would be OK with me if someone can design audio products that don't cost nearly as much, yet sound as good as the best. Of course, some here think that this is already true, but I have not found it so, yet. Often, the same designers who want to save money, also compromise the heart of the design with a number of tradeoffs, including cheaper IC's, passive parts, etc, as well as an inexpensive (usually plastic) case. This is where I try to encourage designers to keep their designs up to a high listening standard, rather than just rely on a set of 'specs' that look good enough in print, but hidden in the design is crossover distortion, distortion in passive parts, etc.
 
it's is MUCH harder to get people to agree on sound than on vision.
We can spend the time we want to complete our experience, while we analyse a photography. It is a static experience.

Sound is a continuously changing phenomena. When we recognize a kick drum, its sound is yet away. We rely on our memory, and, yes, blind or not, we can be fooled, because of this.

By example, because the mask effects, it is not always easy to pick the details of an instrument in a noisy environment (the other instruments).
One of the tricks we use in mixing, when we can, it to let an instrument in front as alone and loud as possible, long time enough for people can analyse its details. After that, you can push-it away more 'inside' in the scene, and let the other instruments cover-it. Listeners will continue to feel all the details and feel this instrument is more present than it is.
One of the tricks Earth wind and fire used to create their incredibly complex and rich arrangements, while you feel you can separate so easily each instruments in this crowd.
 
Curl- Hats off...

Money saved equals quality ost, sometimes in passive parts a better cap will make a profound difference, coils are the same, theres a hell of a difference in the perfomance of a vacuum impregnated "hard as a Rock" foil inductor and the same value much cheaper VAX impregnated, just where do you see that on the measurements..? or how do you see (measure) the minuscule noise improvement in changing resistors from melf's to bulkmetal foils..? How ever audible that change may be.

Or how do you justify spending 1000(s) euro on a midrange membrane just because it behaves better out of band.

Most companies makes products to fit a cost bracket, and for the leadership of most companies money saved=better earnings. and with the number of huge companies own and driven by capital funds small quality based operations tend to drown in the advertising powers of the bigger guns.
 
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it would be OK with me if someone can design audio products that don't cost nearly as much, yet sound as good as the best. Of course, some here think that this is already true, but I have not found it so, yet.
That is the way my system is build. But it is true, too, that, on each gear, i had to do some improvements.
By example, my 1981 Linear tracking arm Technics SL7 was not too expensive, and a wonder of engineering in all its details.
It suffered only from an issue, the plate was too thin, and so, too resonating. Just by replacing the original hard and thin rubber cover plate by a heavy silicon one, changed its 'sound' to the top...
 
John, some good things are happening, but we don't always know about them.

Sometimes, models appear we have no feedback on. I think my own case is rather illustrating. I never much liked NAD. to me they were just another me-too company. They had one mega seller, the old 3020 integrated amp, which was truly speacial at the time, but that was it. So, I made the expected mistake, I never bothered to look at NAD again. Wrong!

A year ago, I decided it was time for a new CD player. I mention this, totally by the way, to a friend of mine, a man whose hearing and evaluation cašabilities I have nothing but respect for. He says - don't buy anything until you've heard NAD's C 565 BEE. So, I make my rounds, armed with CDs, and listen to the latest crop from Marantz, Denon, Rotel and NAD, all in the €400-600 (app. $ 520-780) price bracket. And, to my great surprise, indeed trhe said NAD model literally wiped the floor with everything else for the money, and added insult to injury by cleanly beating the crop of the next price class upwards.

If somebody told me it could ever be like this, I wouldn't have believed him, I admit it. From NAD? Who are you kidding, buddy? But NAD it was. I didn't believe such sound was possible from this price class, just 10 years ago one had to pay ten times the price and still wasn't guaranteed that quality. But times move on, and if we just drop our shields a little, we can be surprised from the most unlikely source. Obviously, somebody in NAD decided to give the competition a lesson.

The best for last - internally, build quality has to be seen to be believed. I am not one bit easily impressed, I'm pretty good in that myself, but I loved it. True, I have seen better yet, but at prices out of this world.

Of course, none of us here researches the market day in and day out, but it does pay to keep your eyes, ears and especially mind wide open.
 
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If anyone wants to check up on me and my views, just buy a second hand Harman/Kardon 6550 integrated amp. Change its caps for the same value using ordinary decent quality parts, no boutique caps, and make sure you swap its volume pot for an ALPS blue.

Then, switch it on and be prepared to be amazed. Truly amazed. Sound quality like you wouldn't believe to be possible in that price class. It sounds WAY better than its elder bretheren from the same line, which BTW already have that ALPS Blue pot factory installed. I should know, I own the biggest brother of them all, the HK 680.
 
I have seen better yet, but at prices out of this world.
And i'm sure that, if one day or an other you decide to change the little details witch can be improved, by examples some OPAs in the audio stages, or adding a driver to the ouput, removing some lytics, ( if you use analog outs ), you can bring-it at a level that no'out of the world' priced gear can beat ;-)
That i had done on my old CD payer.
 
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And i'm sure that, if one day or an other you decide to change the little details witch can be improved, by examples some OPAs in the audio stages, or adding a driver to the ouput, removing some lytics, ( if you use analog outs ), you can bring-it at a level that no'out of the world' priced gear can beat ;-)
That i had done on my old CD payer.

I still don't know about that, I got hold of its service manual just a few days ago and haven't had an opportunity to examine it in detail.

But I did that on my old Yamaha CDX-993. Out went NJR op amps acting as I/V converters, in came fast AD 826 op amps. The difference was immediately recognizable, it kept its warm and cuddly analog sound, but now had added detail ironed out.

In general, you can always improve anything ever made, it's just a question of how much trouble you want to undertake for how much sonic gain.
 
What's Beranek's Law, SY?
Wikipedia does not recognize it.
"It has been remarked that if one selects his own components, builds his own enclosure, and is convinced he has made a wise choice of design, then his own loudspeaker sounds better to him than does anyone else's loudspeaker. In this case, the frequency response of the loudspeaker seems to play only a minor part in forming a person's opinion."
Funny, but often wrong, as all the generalizations.

The only one i found impossible to never contradict is the Murphy one.
But it because it is only when your amp oscillate that you remember-it. ;-)
 
Oops, comes a time when one is unable to differentiate 1/4 dioptre up/down with a classic manual phoropter.
It becomes a guessing game with 50/50 odds.
It's not what one sees, but what one Thinks to see.
Thanks for all that, Jacco, appreciate it. Where I still disagree is that you use terms like "guessing", and "fooling", implying that there's a fudge going on - no, there's not: the optometrist could have a sophisticated reading chart where the sequence of letters is constantly being varied, purely randomly - yes, the brain will use every scrap of information, and prior knowledge to try and work out what each character is, but the only thing that matters is how many you get correct. If you get them all right, you win, simple as that. Which corresponds to there being enough information around, sufficiently uncontaminated, to fully "reassemble" what the reality is.

And that exactly corresponds to the audio situation is about - your ear/brain has to get hold of enough information to properly reconstruct the item of interest, the recording. The latter you want as correct as possible, and all the blurring and distortion artifacts due to what the playback mechanism is adding to the situation have to be reduced as much as you possibly can - the remarkable thing I found, as have others, is that the internally perceived reconstruction can be amazingly "solid", in spite of everything - there's no 'fooling' going on, just that the glasses, contact lenses you're using are absolutely optimised to give your "internal reality recognition apparatus" a good run at it ...
 
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