input resistor v1a

grtamp · Post by **grtamp** » Fri Aug 20, 2010 11:44 am

Hi , in the schematic #124 the input grid res. is 33K , the layout show 22K there ,what is the right value?
Thanks

martin manning · Post by **martin manning** » Fri Aug 20, 2010 12:07 pm

I believe 33K is correct.

bluesfendermanblues · Fri Aug 20, 2010 12:41 pm

grtamp wrote:Hi , in the schematic #124 the input grid res. is 33K , the layout show 22K there ,what is the right value?
Thanks

22k for 50w
33k for 100w

bluesfendermanblues · Fri Aug 20, 2010 12:41 pm

grtamp wrote:Hi , in the schematic #124 the input grid res. is 33K , the layout show 22K there ,what is the right value?
Thanks

22k for 50w
33k for 100w

martin manning · Post by **martin manning** » Fri Aug 20, 2010 12:49 pm

bluesfendermanblues wrote: 22k for 50w
33k for 100w

This resistor is just setting the high-frequency roll-off point for the input stage. Why a different value for 50 vs. 100W?

ericlee · Post by **ericlee** » Fri Aug 20, 2010 1:28 pm

Try 10k

- you will be pleased !

Structo · Post by **Structo** » Fri Aug 20, 2010 4:21 pm

#124 used a 33K.
The layout shows a 22K.
I used a 33K.

gary sanders · Post by **gary sanders** » Fri Aug 20, 2010 4:48 pm

I have 33k in my 50 watt

odourboy · Post by **odourboy** » Fri Aug 20, 2010 6:34 pm

AFAIK 22K is the norm. The only ones I know of with 33k are #124 and the Sunnnyland BM (although I'm sure there are others lurking out there).

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