John Curl's Blowtorch preamplifier part II

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Near Enough Can Be Good Enough....

.....able to 'forgive' some audio reproduction irregularities, so long as another part of the acoustic reproduction is preserved. Apparently, in your situation, the acoustic space, but correct me, if I am wrong.
SM, I agree with what you and John have to say.
Acoustic width and depth recreation/illusion (take your pick) is beautiful when the rest is right.
That said, many systems don't quite get there, and some sort of compromise is the order of the day.
If the system conveys feel, emotion AND groove, I can well ignore a bit of FR issues, and/or a bit of benign distortion, and/or a bit of noise etc..
High enders have all heard clinically correct systems that will just not groove, and leave the listener cold, even subtly irritated.
Same with a mixdown or live mix....everything seems to be right but the groove just ain't there.
I understand natural sound, and I also understand that it is not possible to fully recreate natural soundscapes....some listeners/designers will not accept that fact, and still fall flat in their quest.
My quest is clean, clear and happy sound that entertains and invigorates....this is possible.

Eric.
 
You HAVE IT, mrfeedback! At CES, I heard several playback systems that were BORING! Yes, accurate, but boring. They left you empty. One, had a very similar speaker system as I use, but more updated. I spoke about this to an audio dealer colleague and a very good listener, who also sold the SAME loudspeaker system. He was there, and agreed that it was boring, but ALSO inaccurate. He has very good 'ears', and an expert with these speakers, but I could not immediately hear any departure from clinical accuracy.
 
SM, I agree with what you and John have to say.
Acoustic width and depth recreation/illusion (take your pick) is beautiful when the rest is right.
That said, many systems don't quite get there, and some sort of compromise is the order of the day.
If the system conveys feel, emotion AND groove, I can well ignore a bit of FR issues, and/or a bit of benign distortion, and/or a bit of noise etc..
High enders have all heard clinically correct systems that will just not groove, and leave the listener cold, even subtly irritated.
Same with a mixdown or live mix....everything seems to be right but the groove just ain't there.
I understand natural sound, and I also understand that it is not possible to fully recreate natural soundscapes....some listeners/designers will not accept that fact, and still fall flat in their quest.
My quest is clean, clear and happy sound that entertains and invigorates....this is possible.

Eric.

A local audiophile friend of mine describes it as "making music": some systems "make music", while others do not. Vinyl records seem to "make music", while most CD players do not.
 
Shakin' That ***....

You HAVE IT, mrfeedback!
Haha, why thanks, but I do know that already. :p
My car system is 2 x 8" two ways and a PA plastic cabinet with a 15''.
The bottom end (150 Hz down) bass response is way too big to be called accurate, but it sure is fun, so much so that mates and I will take the long way to the pub bottleo just for the heck of it.
I know the live sounds of some of the bands that I play in the car (I have live mixed some of them) and this system goes the nearest to concert sound that I have found anywhere.
Music is all about FUN !.

Eric.

I have a couple 'Sensurround' vibrators to go under the front seats - these take things to the next level.
 
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John, i was on a busyness trip for some days and i could not follow the thread until today.
I think the first cartridge that made a paradigm shift ( after Ortofon, EMT etc.) was the Koetzu from Sugano San. He found that he could influence the sound by using exotic materials like rare earth magnets, high purity wiring and special cabinet constructions like precious stones or hard wood. Unfortunately i am afraid that many here will not beleave or apreciate this because it is nonsense but the sound the first Koetzu Black made really was a positive shock for me. There was a spaciousness and musicality without the usual rise in the treble that was adictive. Sugano San influenced a lot of designers in Japan also the team at Lyra. They experimented with 6N copper, samarium cobald magnets and cabinets made out of dur aluminum and later titan. Also a lot of diffent shapes of the cabinets have being tryed including "naked" or "nude" designs. Also they way the cantilever was attached to the body and how the rubber damper was made got attention. As you say, more later, if there is any interest.
 
I listened to Lyra MC cartridges after Jonathan Carr, the designer explained his approach to design in a number of posts on this forum. He has given us an inside view of the problems, and at all times proves his grip on the Design Principle of tradeoff, and measuring with good taste as well as instrumentation.

It's not easy to set up these MC cartridges to give their best; it takes a great deal of patience AND mechanical competance. But when you get it right, the reward is a taste of just how good the analogue recording of the 1960s-70s really were. And - how much of a backward step the digital 1980s proved to be, in hindsight, at least.

OK, more please, Joachim.
 
Yes, Joachim, I agree the Koetzu Black was an OUTSTANDING cartridge. It had LIFE!
The Lyra that I now have, will put more of that back into my vinyl playback, which, while using the Blowtorch electronics, is 'missing' just a little bit. Just enough to be annoying with the less exotic cartridge that I now have. I might compare the cartridge that I have to a middle to high quality classical or folk guitar. Good, but NOT a 'keeper'. Yet, for economic reasons, I have kept it for years.
Sometimes, there are 'tradeoffs' in phono cartridge reproduction. Once, decades ago, I listened to the sound of 2 phono cartridges from different manufacturers. One was a Koetzu, the other something else. We used the WAMM's and the JC-80 with a Vendetta front end for the preamp electronics. Dave preferred one cartridge, I preferred the other. I preferred the Koetzu (sp?) because it was more ROMANTIC sounding on human female voice. Dave preferred the other, because it was slightly more revealing of inner detail, that I also heard. I did not, and could not have owned either cartridge because of their great cost at the time, but I had my preference, and Dave had his. So much for 'salesmanship'. Dave and I both agreed that the WAMM at the time, 'took on all comers'. Those were the days!
 
The best sound i heard from a Koetzu was in a system with Oracle turntable, a magnetic bearing tonearm from Germany, a Krell Bi-Wiring system and a pair of Duetta ribbon speakers. The 3- dimensionality, focus and dynamics where amasing and i sat at least 5m from the speakers so this setup was the oposite ( near-medium field ) of i what i normally do. I think that had to do with the line source behaviour of the speakers.
Thinking about why you are not 100% satisfield with the Helicon SL on your Linn, John, it could be that the Azimuth is slightly of. The Linn arm does not allow for Azimuth correction so what could be done is to use a sheet of slightly compressible material like lead or teflon between the cartridge and the arm and use different tension on the screws to put the needle straight. To arive at the optimum position a mono record could be played and a scope fed with a left - right channel signal in antiphase could show the position of minimal crosstalk. VTA is critical too with a fine line diamond so the needle should look straight into the record from the side. Mishima told me that the optimum position is not when the needle looks straight fom the side but when the edge of the micro ridge is straight to the record because the grinded edge is not straight to the diamond. It has a slight angle. In total we have to do 7 adjustments to the cartridge : Downpreasure, Azimuth, Zenith, VTA, Overhang, Crop Angle and Anti Scating.The effective mass has to fit to the cartridge and the turntable needs to be horizontal and decoupled from footfalls and sound from the speakers. All this adjustments influence one another and sometimes i repeat the adjustments in a circle until i get the optimum result. As you see a lot can go wrong here but when it playes, it is a very rewarding experience having done something successfully that is so complicated. I understand why most people like CD better and just listen to the music. I myself get a kick out of analog, despite the difficulties.
 
As far as i know you use a Technics cartridge and at the time it came out there where a lot of innovations like Shibata needles ( for Quatro sound ) and coils on a PCB instead of winding the coils by hand. I had a Yamaha cartridge with this innovations and was happy with what i heard but it is a too long time ago to say how such a cartridge compares to current High End MC´s. I saw a Technics somewhere at 100,-$, so i should buy one.
Technics also made strain gauges and Iverson made a high end version with the Technics element. There was the Stax electrostatic. I only heard the Stax, again a long time ago. There is the Soundsmith strain gauge that i know quite well. It is excellent i think but nedds a special preamplifier and is very expensive too. I have no hope that technology like that comes back into more affordable regions anytime soon although i think a strain gauge cartridge with peamp could be made that is not too expensive.
 
Maybe i can catch a Technics strain gauge and make a preamp.
Moving on to answer John question what makes a great modern MC cart i have already mentioned the cabinet ( body ) of the cartridge. In the case of the Titan I i use, it is from Titanium. Why ? Titanium is very dense and strong, actually a bit heavier then Aluminum. The desgner, Jonathan Carr made the experience that the cartridge should be rigidly coupled to the tonearm and the elements in the cartridge should have very good dimensional stability so that relative movement of the cantilever and magnet system should only contain information picked up from the groove and not overlayed with resonances that come from poor mechanical design like weak plastic parts. Going to Titanium is a bit extreme but the resulting sound was a success. Titanium is hard to mill so the Titan bodies are made " by old guys on traditional mashinery". That explains part of the enormous cost of that cartridge. One other detail is the diamond coated boron cantilever. In fact it is an artificial amorphous diamond coating. It contains carbon and hydrogen and was developed by the late Dr.Enke for long lasting surface treatment for example on the pistons of Renault Formular 1 motors. The company i was working for did the PSU´s for Dr.Enkes vacuum process so i got to know him back in the late 80th. I told Stig Björge of Lyra that we can coat cantilevers with artificial diamond to raise stiffness and damping. So Mishima San made a tool of not more then 1.5 x 1.5cm that can hold 100 cantilevers in the vacuum chamber. You have to see that delicate thing in real to apreciate it. So again, one more expensive process with shipping back and forth between Germany and Japan.
 
Joachim, thanks for sharing YOUR experience with us. At the beginning of this topic, I mentioned that I only knew that you would be able to contribute significantly here. I am glad that some others also have real experience with the better cartridges.
First, I must clarify the situation:
It is the DORIAN that I have used for the last 5+ years that I am NOT completely satisfied with. I have NOT yet tried the SL in my tonearm, because I have been busy, very busy in fact, working on a phono stage, and my bench is full up.
Just changing the cartridge, without adjustment, as your concern shows, might well be a mistake, and certainly not optimum.
Now what about other, more exotic designs? My associates and I have tried most of them. Their biggest problem seems to be in the cost and complexity of the approaches. We have tried: Strain gage, variable capacitance, laser pickup, off the top of my memory. ALL had problems, took special electronics, usually inferior to the best efforts of tubes or solid state, and cost big money. They did do INTERESTING variations on what we got from the record, and this was interesting, but usually everybody, even with deep pockets, went back to the Moving Coil playback.
 
Yet Panasonic, Weathers, Win, et al managed to bring them in at a competitive price. And these were some of the best cartridges ever made.

I suspect the old, "We've always done it this way" constraints, along with "We're already tooled up to make MCs, we don't have the right capital equipment to do other technologies." It's an opportunity for someone creative and daring enough to jump into that niche. Probably not you, John, your space is in the more tradition-bound markets, but maybe someone like Joachim...
 
SY, as I tried to explain, a reproduce stage that must go along with an exotic playback system is STUFFED with op amps. Why don't you, in your spare time, make a strain gage, etc playback with tubes? Don't have the time, don't have the room? '-)
The PROBLEM is in the COMPLEXITY of the reproduction, and many amazing designs have fallen by the way-side as being too expensive, too impractical, too narrow in function, and often, mediocre overall sound.
If everyone will just read the latest of Joachim's responses, you will find the SECRET to refinement, (and extra cost) is in the cartridge mechanics itself, not the method of transduction, which can be interesting, and maybe important, but not so important as to be worth the time and effort.
It is true, that I will stick to MC and MM cartridges. Why not? I am older, well established in a niche, and THEY DON'T PAY ME TO DO HEAVY RESEARCH. If someone did, then OK!
 
Yet Panasonic, Weathers, Win, et al managed to bring them in at a competitive price. And these were some of the best cartridges ever made.

...

MEMS? One wafer would be a lifetime suipply. GE makes silicon strain guage pressure sensors.

BTW Vishay or BLH could certainly duplicate anything done 30yr. ago . Any detailed references?

I've heard the best is simply high res imaging of the entire groove with lots of computing horsepower.
 
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I have had experience with both Win and Iverson's strain gauge and with the Stax. The strain gauge cartridges that were made all suffered from a serious design challenge. The stylus was coupled to the strain gauges with a rubber "T" connection. Part of the eq was in the compliance of the rubber. It changed considerably with temperature and time. A modern design could be made with real strain gauges bonded to a stylus across the flex point but it would not be simple and the output may be very low.

I worked with Stax a generation ago on trying to improve the FM cartridge. At the time getting a low enough noise oscillator at a high enough frequency to get serious signal to noise wasn't possible. We were trying to make an early mmic that would be part of the body. I think we were almost a generation ahead of the curve. It would be quite possible today and could be cost competitive with current premium cartridges.

Other novel options were the vacuum tube cartridge (the grid was connected to the stylus) and optical cartridges. The optical approach is used in real state of the art transducers: Atomic force microscopy - Wikipedia, the free encyclopedia and could work for a phono cartridge if someone has a million or so to devote to the problem.

There is also this: http://en.wikipedia.org/wiki/Laser_turntable which has had a very checkered history. I know one guy who had one and really liked it except the inner groove distortion became too irritating for him and he sold it.
 
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