Well, Thorsten, I will see you out in the audio arena, when people across the world compare your best efforts to mine, as has been done for the last 35 years.
Audio Origami PU7 has few peers.
An externally hosted image should be here but it was not working when we last tested it.
It would probably work better if you attached those dangling wires to a cartridge.
The sheet (IF3601) I got was a little different (no graphs) but I see the 750mS is at Idss so the noise will be more at 5ma. They show almost constant gm on the first graph which would be strange unless the extrinsic rs is almost as large as gm, in fact none of the graphs look to represent exact data. The biggest difference I see though is in the capacitances listed.
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I don't even know enough to ask the question properly, but maybe you can read between the lines... : In vacuum valves the Childs power law is based on a lot of assumptions like infinite parallel planes, etc. and some very linear devices can be made by massaging the real world geometry. It seems to help to be larger too.
But is that the case with semicon field effect devices? Or is the extrinsic r_s a simpler issue of being only a result of 1/gm? And gm itself (and its variation with I_d) solely the result of geometry?
That's as clear as mud. Sorry, and if you can't make anything out of it I certainly understand.
Much thanks,
Chris
In fact I think I can find the exact place on a French curve where that noise plot fits 😉 In any case I consider it my duty to explore these devices further, ASAP.
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Well, other people buy cars for a million $ and i have my hobby. 🙂
The 103 can work with your MMT, but you have to add weight ( at least 10 gramms)on the headshell and a heavier counterweight to get correct LF res around 11Hz. Second do not tigthen hard the body to the headshell and use brass screws therefore.
And lift the arm base apx. 3mm to get correct angle of the stylus.
Track with 2, 4 gramms, this works best since you have a almost defined contact surface which is round and does not change with modulation.
Reduce antiscate force to the half.
Most people will not believe that vinyl have to played with spheric tips, since the like to believe liars and there selling crap skills.
Vinyl is anything than perfect, but well executed it sounds really good.
Cutting heads use Feedback and need ups to 600 Watt clean power to be driven! Cutting headtips must be heated to work. Cutting machines work almost with direct drive. Analog records must be compressed ( with analog compressors usually). Cutting heads have almost a strong resonance around 19 Khz and thus they need a notch filter there. Records have to be limited in bass below 30 Hz.Most records have been done with Dynagroove.
And it can sound so good.😎
Hi,
The funny thing is to see the people who normally present themselves as the debunkers of all silly things end immediately springing to the defence of line contact and elliptical stylii simply because the notion is advanced by someone they have already decided is somehow trying to sell something to everyone by making false statements... I am very amused.
Yes, I completely agree. In many cases vinyl as medium is not the limiting factor.
Not for DMM. When cutting DMM you need a very high frequency "bias" to be able to cut the audio signal into the copper layer... In many ways DMM was a dramatic advancement over cutting lacquer, but it came too late and was never fully developed to it's best performance...
In my day and age the "analogue compressor" was called "Tonmeister" and this "analogue compressor" used a technique called gain-riding while reading along with the orchestral score.
Even more funny perhaps, the "Tonmeister" usually used a Fader with build in level dependent bass lift (that is, with a correctly designed physiological level dependent frequency response - not the usual stupid loudness bass & treble boost)...
If most audiophiles knew how LP's are really made they would recoil in terror, as would most technocrats...
Only he who really knows and does not care about perception or beliefs can listen happily anyway, also to CD for that point, to transistors or tubes.
Ciao T
The funny thing is to see the people who normally present themselves as the debunkers of all silly things end immediately springing to the defence of line contact and elliptical stylii simply because the notion is advanced by someone they have already decided is somehow trying to sell something to everyone by making false statements... I am very amused.
Yes, I completely agree. In many cases vinyl as medium is not the limiting factor.
Not for DMM. When cutting DMM you need a very high frequency "bias" to be able to cut the audio signal into the copper layer... In many ways DMM was a dramatic advancement over cutting lacquer, but it came too late and was never fully developed to it's best performance...
In my day and age the "analogue compressor" was called "Tonmeister" and this "analogue compressor" used a technique called gain-riding while reading along with the orchestral score.
Even more funny perhaps, the "Tonmeister" usually used a Fader with build in level dependent bass lift (that is, with a correctly designed physiological level dependent frequency response - not the usual stupid loudness bass & treble boost)...
If most audiophiles knew how LP's are really made they would recoil in terror, as would most technocrats...
Only he who really knows and does not care about perception or beliefs can listen happily anyway, also to CD for that point, to transistors or tubes.
Ciao T
Yes, DMM is different. They used apx. 70 Khz Bias, right?
And had sometimes burn out on the cutting heads when not carefully level controlled.
Its also amusing that Audiophile People can hear different low bass from L and R, altough their records are almost mono in this area . 🙂
I would like to now what specs. are declared today from record pressing plants to the guys with mastertapes. Somebody told me, they have to be mono in the bass, nothing below 30 Hz and nothing real above 15Khz, but i dont know if this true.
And some people use Shibata tips for stereo records. And wonder why their system is noisy and has 6 dB lesser in level than other cartridges. :-/
And had sometimes burn out on the cutting heads when not carefully level controlled.
Its also amusing that Audiophile People can hear different low bass from L and R, altough their records are almost mono in this area . 🙂
I would like to now what specs. are declared today from record pressing plants to the guys with mastertapes. Somebody told me, they have to be mono in the bass, nothing below 30 Hz and nothing real above 15Khz, but i dont know if this true.
And some people use Shibata tips for stereo records. And wonder why their system is noisy and has 6 dB lesser in level than other cartridges. :-/
I think that you two engineers, Groove-T and Thorsten have very strong opinions. They barely make sense to me. For example, Why 19KHz? Most cutters have a higher self resonance and are flat at 19KHz, due to the droop in HF pre-emphasis due to a 40KHz shelf, balanced against a slight boost from the resonance that will develop between 25K and 30KHz. What about 1/2 speed cutting? Perhaps I am 40 years behind, but then that's when most of the 'interesting' records were made, as well, at least in my collection.
Thanks, that is in general agreement with what Thorsten said about non-rigid headshell contact, and I see my golfers club weighting tape will come in handy 🙂, last I checked my usual Grado is at exactly 10Hz. BTW the table and arm are the same ones TAS used in their 1984 review, I bought them from the reviewer. Another project for the new year.
I think this vinyl revisionism is fun, some of the best stuff I've seen here in a long time. Where was this input when folks like HP were doing up thieir super disk lists?
One cannot make a photo free of reflections with the dust cover down in the closed position 😉
Hi,
Around 70K sounds more or less right. I seem to remember the frequency had to do with avoiding producing in band IM products with the sample rate of the digital delay in the forward signal path used for automated variable groove spacing.
Of course, when cutting "serious music" the cutting engineers I knew would disable this and control by hand, using "feed-forward" based on the musical score (kind of their equivalent to my gain-riding where I would slowly boost the levels as the orchestra segued into a ppp passage and slowly attenuated as they headed for fff, from my relative "0dB" point...
I do not know about now, but while not quite Mono-bass, you where not allowed much difference. I'm not sure about the 15Khz, I do not remember it being specced, but you could not have very high levels above around 3Khz, equally, you could have bass below 30Hz, but not at high levels...
The fun part, similar requirements are still applied to CD's, in order to ensure radio play compatibility, where Mono-compatibility is still often king (I suspect mainly due to the US being one of the biggest markets and being backwards enough to still have medium wave AM Radio as mainstream radio)...
Ciao T
Around 70K sounds more or less right. I seem to remember the frequency had to do with avoiding producing in band IM products with the sample rate of the digital delay in the forward signal path used for automated variable groove spacing.
Of course, when cutting "serious music" the cutting engineers I knew would disable this and control by hand, using "feed-forward" based on the musical score (kind of their equivalent to my gain-riding where I would slowly boost the levels as the orchestra segued into a ppp passage and slowly attenuated as they headed for fff, from my relative "0dB" point...
I do not know about now, but while not quite Mono-bass, you where not allowed much difference. I'm not sure about the 15Khz, I do not remember it being specced, but you could not have very high levels above around 3Khz, equally, you could have bass below 30Hz, but not at high levels...
The fun part, similar requirements are still applied to CD's, in order to ensure radio play compatibility, where Mono-compatibility is still often king (I suspect mainly due to the US being one of the biggest markets and being backwards enough to still have medium wave AM Radio as mainstream radio)...
Ciao T
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