I'm trying to get a straight answer out of him about questions of fact. Instead of answering he is using every evasion tactic known to man including now claiming that I speak Russian.In the field of audio It does not make sense to question personal opinions.
In the manufacture of Audio devices . The laws of physics don 't work . For example, a capacitor with a dacron dielectric sounds different from paper -oil .or Teflon . The nominal value is the same 300B lamp manufactured in WE and China, the difference in sound is space.They are visually identical . I compared it myself. How can I explain this? What instruments can I use to measure ? and this is not a fairy tale "The Naked dress of the King " Do not try to get answers to your questions anymore. But I 'm sad , you don 't need them . everything sounds the same to you.ovoЯ пытаюсь добиться от него прямого ответа на фактические вопросы.
How to explain the difference in the sound of a Stradivarius violin and some kind of production of an underground artel . Aren 't they both nominally violins ?
LR correction networks (i. e. without capacitors) in RIAA stages I have never seen until now.
Which is rather surprising, the AN is perhaps obscure, but not noticing Van Den Hull's Grail?
Having played with both LR and LCR i decided the LCR provides more of the type of sound i am looking for. All experiments were done with Tango's inductors values, perhaps with others the conclusions may be different.
Why no cathode resistors? There is nothing to linearise the response.
How much lower distortion do you expect with cathode resistors? And have you compared the sound?
Counterpoint once went to the extent of adding an input capacitor just to avoid having a degeneration resistor...
I have a sad experience of using resistors. I made a discrete gain switch on resistors. and thought what a good fellow I was. Over time, I made a transformer with taps for this switch. The effect was like taking cotton wool out of my ears. After that, I try to get rid of cathode resistors, and do not use them in the audio path at all, sometimes I use LEDs. But please consider this my personal experience. And not something I read on the Internet.
I try to use wire resistors, palladium contacts to regulate gain. Military use is possible. They are better than Alps and other brands.
Изготовлен мной с минимальным количеством конденсаторов. Я считаю, что именно они негативно влияют на звучание. Устройство состоит из 2 блоков - блока питания и самого корректора.View attachment 1347220View attachment 1347222
I understand that the person simply does not hear distortions. Or he likes the sounds that create distortions of the unbiased grid)). And his religion does not allow him to take measurements).On the one hand, I am happy for you that you have your own opinion on this. On the other hand, I feel sorry for you that you find this a delusion. I have made several custom phono amplifiers using different designs and different components. And I have an idea of what the sound can be. I do not pretend to be an absolute statement. This is a forum, right? So there may be different opinions. I respect yours, although I know that you are wrong. I have been designing for a long time. More than 25 years. I will post several photos of correctors and an amplifier that I made earlier.
I don't understand the term in the topic "RIAA LR correction".
I know only RC resp. CR networks (usual in use) and LCR networks in RIAA stages.
if you mean such LCR networks ("RIAA LCR correction"), check out the URL's in post #8 under
https://www.analog-forum.de/wbboard...k-welche-prinzipiellen-unterschiede-existier/
LR correction networks (i. e. without capacitors) in RIAA stages I have never seen until now.
Quite an old story, Pete Millet, Stephie Bench or here:
https://forum.intactaudio.com/viewtopic.php?t=1242
https://forum.intactaudio.com/viewtopic.php?t=1254
What makes you think the grids are unbiased? Maybe not "reading' the schematic or just ignorance??Or he likes the sounds that create distortions of the unbiased grid.
The person said that there is no bias resistor in the cathodes. Is there an electronic circuit???
It's a great circuit, despite the ignorant hate spread on it. It's like telling Bob Ross that he's a moron for using a paint brush because you could just print the image with a printer.
The tubes are clearly biased from an external bias supply. Omitting the cathode resistors yields better performance usually.
There is a problem tho, it's hard to drive an RIAA EQ. Hence the Audio Note using a paralleled cathode follower.
It would be a great idea to add a cathode follower to your design too, before the RIAA EQ. Or some other circuit that gives low output impedance.
Perhaps the stage after the RIAA EQ in the Audio Note circuit... iirc that's called a "White follower"
Or if you're allergic to cathode followers, you could use an output tube to drive the RIAA EQ. Many iconic mic preamps and compressors used output tubes to drive seemingly trivial stuff.
If you want to get rid of other resistors (as well as get more gain, probably less THD too). You could use constant current sources.
Especially on the cathode follower. (Yes you can easily do that with tubes)
Wire wounds are inherently more inductive, so that might be a problem. It might also color the sound by mellowing out the transient response.
There are less-inductive wirewounds out there but I suspect those NOS soviet resistors aren't it.
You also need load resistors across the transformer secondaries to get a proper response. And for the input STU you'd need that for a proper load on the cartridge
Something like this perhaps.

The tubes are clearly biased from an external bias supply. Omitting the cathode resistors yields better performance usually.
There is a problem tho, it's hard to drive an RIAA EQ. Hence the Audio Note using a paralleled cathode follower.
It would be a great idea to add a cathode follower to your design too, before the RIAA EQ. Or some other circuit that gives low output impedance.
Perhaps the stage after the RIAA EQ in the Audio Note circuit... iirc that's called a "White follower"
Or if you're allergic to cathode followers, you could use an output tube to drive the RIAA EQ. Many iconic mic preamps and compressors used output tubes to drive seemingly trivial stuff.
If you want to get rid of other resistors (as well as get more gain, probably less THD too). You could use constant current sources.
Especially on the cathode follower. (Yes you can easily do that with tubes)
Wire wounds are inherently more inductive, so that might be a problem. It might also color the sound by mellowing out the transient response.
There are less-inductive wirewounds out there but I suspect those NOS soviet resistors aren't it.
You also need load resistors across the transformer secondaries to get a proper response. And for the input STU you'd need that for a proper load on the cartridge
Something like this perhaps.

Thank you! I looked at the schematic... Why so complicated??? It's just a frequency response corrector... Why use very bad-sounding Soviet resistors with parasitic inductances? Why a transition capacitor after the first stage? It definitely spoils the sound. Guaranteed. Why not use interstage decoupling transformers, if such a concept has already been chosen. In short, the man is not in control of himself yet). He presented his diagram too early. It is raw and excessively complex. I won't even mention the choice of vacuum tubes).Did you check the schematics in post #1 - #5?
The tubes are biased with negative grid voltage; in tube terms we call that fixed bias.
Fixed bias is supposed to give lower distortion than cathode bias.
The man is enough in control of himself to know that the high Rp of the input tube will not allow interstage coupling.
The "transition capacitor" is there to block DC.
May I advice you to apply some self-control by first learning instead of posting? You seem to lack the basic knowledge.
The "transition capacitor" is there to block DC.
May I advice you to apply some self-control by first learning instead of posting? You seem to lack the basic knowledge.
It seems to me that you need to learn yourself, since you do not understand what an interstage transformer is))) If a person has adopted such a concept for this circuit and he cares about the sound quality)) and does not want to put shunt capacitors (for example, the excellent-sounding Black Gate F for bias resistors of electronic tubes), but uses a fixed bias that is quite unstable for low-current circuits. Do you understand my maxim?
You are wrong, the Soviet resistors in the photo are wound bifilarly, without induction and are not used for household purposes, but in precision measuring devices 0.5% and elsewhere. The capacitor after the first stage is installed because of the high Ri of the 12SC7 lamp. It will not be possible to wind a transformer for it.Thank you! I looked at the schematic... Why so complicated??? It's just a frequency response corrector... Why use very bad-sounding Soviet resistors with parasitic inductances? Why a transition capacitor after the first stage? It definitely spoils the sound. Guaranteed. Why not use interstage decoupling transformers, if such a concept has already been chosen. In short, the man is not in control of himself yet). He presented his diagram too early. It is raw and excessively complex. I won't even mention the choice of vacuum tubes).
Yeah it would. TFK used chokes as the plate load in their preamps with high Ri tubes. In the >100H range
But directly coupled designs also exist. You could just pair it with a CF and negate that problem. But you haven't said what you want from the preamp. maybe it's just a show and tell thread.
But directly coupled designs also exist. You could just pair it with a CF and negate that problem. But you haven't said what you want from the preamp. maybe it's just a show and tell thread.
Just a small remark: you drive the LR equalising network from high source impedance of the first tube anode.
However in the Audio Note circuit the LR is driven from low source impedance of the first tube cathode.
I suppose it alters the frequency response of the RIAA network. It should be simulated and changed accordingly.
Otherwise a nice circuit and build quality, congratulations!
However in the Audio Note circuit the LR is driven from low source impedance of the first tube cathode.
I suppose it alters the frequency response of the RIAA network. It should be simulated and changed accordingly.
Otherwise a nice circuit and build quality, congratulations!
Hello, you want to go with a 12SC7 into an LR network? This tube has a plate resistance >50kOhm! Have you ever simulated your schematics with an inverse RIAA at the inputs? The AN M10 uses a cathode follower with low output impedance. Using the cascode as driving element would not work. You could check the links I provided how to do such simulations using LTSpice.
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