-90 dBA (see attached screenshot). But input shorted noise is absolutely meaningless and inadequate for ММ cartridge with an inductance of 500 mH and a resistivity of 1 kOhm.
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Dear guys, we are living in XXIth century and anyone can use translate.google.com to understand my russian works. I have also made english subtitles to some my videos about both this phonopreamp, about my HiestFi Power amp (also first published back in 1989 in Radio #6\1989 magazine, but updated last years), my patented modifications of Dolby HX and Dolby HX Pro, PB preamp for open reels and cassets etc. You can also translate almost 100 issues of my Radiohobby magazine - I was an Editor-in-Chief and founder of it in 1998-2014.
Are you sure L-02 with 3 dozens of transistors per channel and 2SK240 input from 1980s is the same as 6-transistors KA9100 and 2SK68 from 1970s ?
How many examples would you like. I've yet to find one WITH that resonance. However always interested in looking at how people approach different cartridge loading schemes. Sadly the trouble makers have already started to mark their territory here...
Well I' m curious what is your complete russian name and the first published article in Radio on dynamic tape bias.
And automatic translation on this site doesn't work properly for many...
My full name in russian is Николай Евгеньевич Сухов or Nikolai Yevgenjevich Sukhov transliterated. My first article on Dynamic Tape Bias System called in russian "СДП" is in Radio magazine archive #5/1983 pages 36-40 http://archive.radio.ru/web/1983/05/040/ but more effective and simple "СДП-2" was published in 1987 http://archive.radio.ru/web/1987/01/044/ . My most perfect Adaptive Dynamic Bias System was a patented modification of Dolby HX Pro and published in 1991 http://archive.radio.ru/web/1991/06/054/ . The Patents are here https://uapatents.com/patents/sukhov-mikola-ehvgenovich https://patents.su/3-1448357-sposob-magnitnojj-zapisi-s-adaptivnym-podmagnichivaniem.html If you have any trouble with translation, ask me a questions and I will help in English.
my cartridge loading scheme (I call it Aperiodic) with 150 kohm and 25 pF input is indifferent to cartridge inductance and resistance. You can test my model in Microcap XII circuit simulator [ the circiut file is here https://www.patreon.com/posts/68010671 ] , - the maximum peaking is no more than 1.5 dB @ 35 kHz - see attached screenshot
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Thank you! I have read only some articles reffering to 1986-1987 magazines collections.I just wanted to know more as I'm a big fan of using tapes.
I think you could talk with Ian Didden here and send your articles translated in english to be published in Linear Audio or maybe translate it and have it in any other english publication of your choice.I've seen some really interesting schematics in some Radio magazines, but other than that they are photocopied and I don't know how to transfer photocopied content to Google translate plus we don't normally use russian alphabet while our keybords are filled with roman alphabet characters so again...language barrier.
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You need to couple the preamp straight at tonearm's terminals to get 25 pF.We just have a big problem with the aforementioned resonance at 14-16khz which is nowhere to be found in cartridges with normal loading.Is that range of resonance caused by the unusual light loading and then corrected by your unusual feedback network so that we can say you changed the usual mm cartridge resonance range then damped with overall results being the higher SNR? I can believe something like that , but then we can't use your preamplifier in a normal setup using cables between the tonearm and the preamplifier as 1m of the best cables cables present well over 50pF of capacitance.
I have read a romanian article refferencing to 1987 Radio article, even bought 2 cassette players having those bias chips yet never used them.
Also found a Karat MP_202C double deck which i was impressed of,(i know there are better decks than this...) but it's defective (probably thr regulator section ...and wjo knows what rlse?) and I couldn't find a schematic for it.Could you help me with that so that i can give it a new life? It has these chips whic look like some sort of dolby processing but no clear ideea: https://kiloom.ru/spravochnik-radiodetalej/microsxema/k157xp3-ka157xp3.html
Also found a Karat MP_202C double deck which i was impressed of,(i know there are better decks than this...) but it's defective (probably thr regulator section ...and wjo knows what rlse?) and I couldn't find a schematic for it.Could you help me with that so that i can give it a new life? It has these chips whic look like some sort of dolby processing but no clear ideea: https://kiloom.ru/spravochnik-radiodetalej/microsxema/k157xp3-ka157xp3.html
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What model have you used for the cartridge generator? I have found that manufacturer specs are woefully inadequate (and commercial MM designers don't seem to have considered loading properly for about 30 years
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Any MM head has an inductance, isn’t it? Any preamp has an input capacitance, right? They make up a circuit tuned to this resonance frequency of a particular head
May be I will do that in near future, but at a time I hardly work on a lot of my new projects (you can see most of them here: patreon.com/nick_sukhov ) and it is very difficult for me to find time for a rather laborious literary activity
Yes I know the problem. You can use so called Optical Character Recognition (OCR) program, best of all FineReader (for russian texts even if your PC have not russian), to convert photocopied jpg to Word text or pdf, and after that freely send it to Google translate. At a time I am living in a smaiil village on west Ukraine and have only a cheap netbook here, but when the war is over, I will return to Kyiv, and there I have a powerful computer and I will help you with my Finereader