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6k pp OPT options

ceylon

ceylon

AK Subscriber
Subscriber
i may pick up a pair of fisher 500c OPTs, which, as best i can pick up from readin thru AK, are 6k->8 ohms pp.

with 6.6k bein dead on for cathode biased 6L6 pp,

what about 6K?

are there EL34 or 6L6 pp or 807/1626 output stages that just LUV 6K plate to plate?

thanks
fellas
 
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Yes, EL34 and 6L6 accept 6600 ohms or 6000 ohms PP in Ultra-Linear connection : it is mentioned in the tube's datasheets.

T
 
I think the 6.6k value for a 6L6 family tube is actually fixed bias. Most of the cathode bias ones ran higher impedance, somewhere in the 7.5-10k range when running UL mode.
 
ceylon said:
but the fisher 500c arent UL
Click to expand...

I get that. Just saying that a 6.6k in pentode mode is a good fit for fixed bias, but may not be optimal for cathode bias. With those datasheet conditions it should give you pretty close to 25 watts into a load. My own 6L6 amp runs 415 on the plates and 250 on the screen, fixed bias into 6.6k and it makes 23 watts.
 
Anything from 6K up will work very well with the 6L6. Technical types like to optimize the numbers, but really it's just not that critical. Basic transformer characteristics such as frequency response, phase shift and linearity are much more important and more audible than the minor difference you're asking about. My recent monoblock build used 4K Harman Kardon transformers with Sylvania 6L6GB outputs (pentode mode). I'm listening to them now, and sound quality is excellent.
:banana:

Jack
 
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