#56 tube line stage

[Burnedfingers]

I did a search on a #56 tube line stage and nothing came up so I will ask if anyone has built or listened to one and if they have what their impression of it is.

 

[The-Planet]

Search for 76 based circuits - electrically indentical, just 6.3 vs 2.5v filament.

27's are also fairly similar for some ideas.

Berman did a nice 76 linestage in Sound Practices at one point, I could did out a copy...

- Gary

 

[Burnedfingers]

Gary,

I did a search and came up with a line stage design from Gary Primm that uses I believe a CCS. It uses a MJE350, 2N2907, several resistors and 2) leds. I don't know if I am allowed to post the schematic of it or not.

I also found what I thought was an interesting idea in Morgan Jones second edition of Valve amplifier page 97. This shows the basic concept for the design of a fixed bias cathode follower.

I am wondering if anyone has built/listened to either concept and if so their views.

 

[mcs]

I would probably make something similar to the Berman design - it's on my (much too long) to-do list. It uses a 76 grounded cathode stage direct coupled to a 6J5/6SN7 cathode follower.

Here's my own simplified schematic:
http://stiftsbogtrykkeriet.dk/~mcs/BB76.gif

Best regards,

Mikkel C. Simonsen

 

[Burnedfingers]

Mikkel

Your schematic looks interesting so I believe I will try it.

Now to find some good #76's

 

[mcs]

Now to find some good #76's

If you already have some #56s, then why not use those?

Best regards,

Mikkel C. Simonsen