211 SET 40W output design and mfg.

[ja2dhc]

Hello from Japan !

I am now ordering a custom made 211 SET amp to
a Chinese garage manufacturer as the below responsibility
splits.

Myself: Circuit Design
Chinese Manufacturer: Mechanical Design and Mfg.
Transformer design for Power and OPT.

The circuit schematic is shown in the below URL.
I expect the output power is 40W which is verified by
TINA simulator.

http://userdisk.webry.biglobe.ne.jp/013/400/99/N000/000/000/128279164650116219848_211-ver5.gif

It is rare case that 211 SET ouputs 40W.

I expect the amp will come up one month later.

 

[Tubelab_com]

It is rare case that 211 SET ouputs 40W.

I have built an amp that uses 211 or 845. It puts out just over 40 watts. The tube must run in A2 to get this power, which is not a problem with a good driver. The secret is a good follower, you use a 6BQ5, I use a mosfet. You use 7K ohm load on 1000 volts, I use 10K ohm on 1100 volts. Both simulate to about 40 watts using Tubecad SE amp cad. It should work very well and sound nice.

 

[ja2dhc]

The secret is a good follower, you use a 6BQ5, I use a mosfet.

Yes, Power Drive is the essential key to get 40W. The attached table shows
comparison by each follower tubes. The same condition to all tubes is 10V
input to the grid and each column shows output voltage (cathode voltage
ie: driving voltage to the grid of power tube).

I obtained this table by TINA simulation for 805 A2 operation (sorry not
211 case). As you can see, 6BQ5 has stronger driving capability than EL34.