Interstage trans? Yes please!

[Gluca]

Ciao belli,

I am messing about with this PP idea. Any suggestion for the interstage trans?

Gianluca

 

[audiousername]

You will quite likely find it very difficult to match the 6C45Ps

EDIT : Have a look at this thread.

 

[Gluca]

That's very true. I'll give anyway a try. Should matching result impossible I'll revert to a single 6C45pi driver stage

Gluca

 

[Brett]

That's very true. I'll give anyway a try. Should matching result impossible I'll revert to a single 6C45pi driver stage

Gluca

Good luck. I'd go for the 6C45 parafeed running a CCS into an IT w/o a gap for lots of inductance. Works well.

 

[Peter Menting]

You might take a look at the "Seth" monoblocks on the Magnequest site. There is a detailed write up on them that can be downloaded from the site. I am currently rounding up parts to build the Ralph Powers PP amp using the 6C45PI and a pair of interstage trans. from Jack at Electraprint.

Hope this helps.

Pete

 

[Gluca]

@ Brett

something like this ???


@ Peter

what inter trans did you pick up from electraprint?


Any comment about the CCS/driver bias?

Gianluca

 

[Peter Menting]

I have two of the 35PPG's on order to go from the plate of the 6C45 to the grids of the output tubes. (Still undecided whether they will be 6B4G's or 2A3's.

Am not planning on a CCS but that's just my choice, no knowledge of how it might affect the sound.

Pete

 

[Brett]

@ Brett

something like this ???

No. Use the CCS as an anode load, cap couple the IT between the 6C45 plate and ground (or return it to the cathode). I have no way of drawing a cct for you, so here's Kurt Strains's 47PP prototype. Some of the component values were changed later, so just use it to see the topology.

 

[Gary P]

Originally posted by Gluca
Any comment about the CCS/driver bias?

A single ended stage will only work with the CCS on the plate. If you place a CCS on the cathode of a single ended stage it will force the plate current to be constant regardless of how much signal you drive into the grid. No change in current equals no gain.

The schematic above of Kurts variation of the 47P-P is the correct way to use a CCS in a single ended parafeed setup.

Gary

 

[Gluca]

mmm thanks for the clarifications. I believe I will start with a simpler topology/tube. What about E88CC PP + IT + 2A3 PP?

Gianluca

 

[Brett]

http://www.nutshellhifi.com/triode1.html

 

[Gluca]

Sweet. I knew that. I will try this one, w/o regulators on driver. thanx Brett