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Converting Solid State to Tube Rectification on a Preamp

I am looking to convert my Preamp from a Bridge Rectifier to a Tube Rectifier.  Any members have done or knows how to do this. Your help are much appreciated!


128x128zipost
imhififan's avatar
imhififan
652 posts
 
@zipost
Do you have the schematics of your Blue Circle 21 preamp? and what is the B+ voltage?
BTW, I also found a BC21.1 with outboard power supply on usaudiomart.
http://www.usaudiomart.com/details/649027319-blue_circle_211_tube_preamp_with_bcg31_power_supply_fre...
imhififan's avatar
imhififan
652 posts
 
...so you need to check all 4 tubes in tube rectifier bridge if operational?
So, it can be done, the question is why you want to do that!
czarivey
4,494 posts
 
So, it can be done, the question is why you want to do that!

Well, if it's to me, than perhaps I can assume some degree of masochism as tubes get blown over 10 times faster than diode.

 I think the best bridge approach with vacuum tubes can actually be done with 2 triodes as each triode can be represented with equivalent 2 diodes.


larryi
1,972 posts
 

czarivey,

Do you think your two triode ideal approach might explain why the manufacturer of my phonostage utilizes two 300b (or two 2a3s) as rectifiers in the power supply section?

zipost's avatar
zipost OP
112 posts
 
Imhififan... the voltage on the secondary power transformer is around say 350v.   As an option on this preamp; Blue circle website do sell a separate power supply, pretty sure it will work with my preamp.  But i do not want to take that route.  

why would i change a solid state rect. to tube??? I am curious to see if a tube rect will outperform a solid states in my preamp.  All members feeback are much appreciated!  
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