I wanna mod my Parabees! with a magnequest interstage transformer and possibly change the driver tubes. Any advice/or ideas? I particularly like the feel of the RIT-5 and really appreciate Mike L. craftsmanship Is it just a simple to swap out, the coupling cap for the transformer, the bias in below 85 seems like it'll fit right in? The original 6N1P's are running in a srpp an early mod to the stock parabee which i like but maybe its time for a change. I have some nice other tubes that i have gathered including 417a and 801a which i think might make good simple driver circuits that could run off a CCS like the original Parabee schematic. I am in real need of sound advice, thanks for your help. David
Parabee modified for interstage transformer
- Thread starter anystereo
- Start date
No, the 5K load of that interstage transformer is not a good match or the driver in the Parabee. By the way, the RIT-5 is a parallel feed interstage transformer, so you'll need to feed them with a coupling cap if you do use them. You'll need a very different driver tube or a three stage amp to use these appropriately.anystereo said:
I would need some more clarification to determine what you might mean by this.anystereo said:
As a driver tube, you need a lot of gain (mu), which the 417A has. You'll have to figure out how to deal with the enormous voltage drop required (417A doesn't want more than 200V on the plate), then I would listen to the whole thing without the interstage transformers before temporarily installing them to have another listen.anystereo said:
You'll lose 11dB of gain by going to an 801A driver (you'll also have to figure out how to supply DC to the filaments). If you have the BeeQuiet, you could assess whether or not you can tolerate 11dB of loss (it has ultimately very little to do with the preamp, but a lot more to do with your speakers and sources).
-PB
-PB
