Hi ! It's not difficult at all; just tedious work; after reading over and over...

Posted by Interstage Tranny (A) on February 26, 2011 at 18:00:00

In Reply to: Hi Interstage Tranny posted by lovetube on February 26, 2011 at 17:37:20:

It can take a long time for the light bulb to be fully lit concerning electronics. Sometimes, the technical theory simply requires memory to "move on" and understand further. As a great example, current flow theory is often taught as passing from positive to negative, or vice versa. In order to work with high current carrying voltages safely, understanding the flow is much less important than remembering not to get any part of your body in the way of any possible current flow, in order to reduce shocks...
You are very welcome !

With EQ circuits, only via studying and rereading, again and again, will the filtering/boosting be comprehended. Seeing a wide variety of circuits, they actually start looking similar. While many peers might believe tweaking cap and R values is confusing, I believe that if you can trust your ears, simple value changing is extremely enlightening. In fact, simply changing the type of EQ capacitor can be ear opening; say ceramic to silver mica or polystyrene.

You are correct that the second 330K to ground is the 6CG7 grid leak R. In many passive preamps, this grid leak value is even higher. For instant satisfaction, simply install a 3300 pf across that 33K R in each channel's EQ pole. Then, later you can upgrade or change at will, after a bit of research. I assure you that the many circuits really do start appearing similar. Remember that the type of EQ cap installed or reinstalled will probably startle your ears. After a bit of break-in time for new parts, your ears will easily tell you whether that circuit prefers silver mica or polystyrene caps. Enjoy the ride and happy listening...

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Follow Ups Full Thread

Topic - phono stage RIAA question. - lovetube 20:24:13 02/25/11 (30)

Google: "Jeremy Epstein 6C45P Phono Preamp page" - kurt s 20:36:09 02/26/11 (13)

RE: Google: "Jeremy Epstein 6C45P Phono Preamp page" - J Epstein 13:00:15 02/18/17 (0)

Thanks Kurt but i use the KAB compute for RIAA value - lovetube 20:42:31 02/26/11 (11)

RE: Thanks Kurt but i use the KAB compute for RIAA value - Stephen R 11:22:33 02/27/11 (5)

Hi Stephen can you help me sim my circuit please - lovetube 15:26:36 02/27/11 (4)

There you go - Stephen R 05:38:03 02/28/11 (3)

RE: There you go...Thanks for your work and Sim... - Minussss3db 20:22:31 02/28/11 (0)

Thanks Stephen - lovetube 05:58:31 02/28/11 (1)

RE: Thanks Stephen - Stephen R 07:26:10 02/28/11 (0)

KAB Lipschitz RIAA calulator - kurt s 23:48:59 02/26/11 (3)

RE: KAB Lipschitz RIAA calulator - lovetube 00:45:17 02/27/11 (2)

I can't do math anymore, maybe :-) - kurt s 01:58:16 02/27/11 (1)

not to worry kurt , we all do that some time - lovetube 20:50:04 02/27/11 (0)

RE: Thanks Kurt but i use the KAB compute for RIAA value - kurt s 23:14:10 02/26/11 (0)

Passive EQ phono stage RIAA question. - Interstage Tranny 17:21:24 02/26/11 (4)

Hi Interstage Tranny - lovetube 17:37:20 02/26/11 (2)

Hi ! It's not difficult at all; just tedious work; after reading over and over... - Interstage Tranny 18:00:00 02/26/11 (1)

RE: Hi ! It's not difficult at all; just tedious work; after reading over and over... - lovetube 20:45:01 02/26/11 (0)

Thanks IT and other who response . - lovetube 17:30:31 02/26/11 (0)

RE: phono stage RIAA question. - Mike C 08:11:01 02/26/11 (0)

RE: phono stage RIAA question. - grhughes 07:27:52 02/26/11 (0)

RE: phono stage RIAA question. - Thomas Mayer 03:37:19 02/26/11 (0)

RE: phono stage RIAA question. - Stephen R 02:36:56 02/26/11 (0)

RE: phono stage RIAA question. - Triode_Kingdom 22:21:11 02/25/11 (6)

The 2122 Hz pole cap is missing. But junk this schematic. nt - kurt s 03:23:20 02/26/11 (1)

Harsh but I would agree. - Stephen R 05:32:39 02/26/11 (0)

RE: phono stage RIAA question. - lovetube 22:24:21 02/25/11 (3)

RE: phono stage RIAA question. - Triode_Kingdom 22:53:31 02/25/11 (2)

RE: phono stage RIAA question. - lovetube 23:28:57 02/25/11 (1)

Passive EQ phono stage RIAA question... - Interstage Tranny 09:05:21 02/26/11 (0)

Follow Ups

Hi ! It's not difficult at all; just tedious work; after reading over and over... - Interstage Tranny 18:00:00 02/26/11 (1)

RE: Hi ! It's not difficult at all; just tedious work; after reading over and over... - lovetube 20:45:01 02/26/11 (0)

Hi ! It's not difficult at all; just tedious work; after reading over and over...

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