diyAudio (
-   Tubes / Valves (
-   -   Passive Magnetic Preamp! (

Matthewong 2nd September 2007 03:19 PM

Passive Magnetic Preamp!
Does anyone listen before the passive magnetic preamp? How is the sound quaity? I would lke to build one and I don't know how. Can anyone give me sme idea and also the schematic as well, thanks.

sawreyrw 2nd September 2007 03:28 PM

If you are talking about a classical mag amp, I don't think it will be at all satisfactory for audio signals.

Brett 2nd September 2007 03:42 PM

If you mean a moving magnet cartridge / RIAA pre, then build Allen Wright's FVP5A from

planet10 3rd September 2007 07:00 AM

Passive magnetic preamp = TVC = Transformer Volume Control

There is at least 1 really good thread here.

You will need a pair of transformers (major expense) some switches to select taps, a switch for sources, some jacks for I/O and a box.

HNere is a good place to start


Steve Eddy 3rd September 2007 07:20 AM


Originally posted by planet10
Passive magnetic preamp = TVC = Transformer Volume Control
Could also = this:


Brett 3rd September 2007 11:55 AM

I've got some S&B TX102 laying about. Wanna buy them?

kevinkr 3rd September 2007 10:42 PM

I've heard a number of passive magnetic line stages over the years, and they all sounded very good.

I heard a transformer based line stage from hificollective and thought it sounded pretty good. (Andy Grove)

One thing to keep in mind if you use this approach is that the source impedance of the driving components should be pretty low for best results. Most solid state sources shouldn't have any problem driving one of these and sources like dacs using current tube designs with high transconductance, high current triodes like the 5842, triode connected 6688 or D3A should not have problems either.

stoolpigeon 4th September 2007 10:23 AM

Hi Brett, which version of the TX102 and how much?

dejanm 4th September 2007 05:12 PM

I have TVC based on S&B T102 MK3, silver wiring, WBT connectors, Shallco switches, ... Most of these parts I bought at:

I recommend it highly. It is very natural sounding pre-amp. But what astonishes the most when compared to EAR 864 or Pass Labs X2.5 (to name only a couple that I tested and compared in last 6 months) is the reproduction in the bass area. TVC is so superior in that respect that I was really tremendously surprised. I used different power amps there SS (Pass Labs X150.5) or tube (DIY SET 6C33, or let's say Jadis JA30).

I do not think you will be sorry if you proceed with this idea ...

By the way, on the Bent Audio site you have all necessary schematics for connecting S&B 102 trainnies ...

All times are GMT. The time now is 12:19 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio