Repeat the measurements and calculation from primary to secondary like I said . 5K vs 4K is not such a big mismatch to explain a massive loss of power . Maybe 10W less or so .
In the AB1 region, (when one tube is cut off) negative feedback reduces the 'effective rp' of the single tube that is on.
That one factor, causes more output power before the amplifier starts to clip.
That is what I have been trying to communicate.
That one factor, causes more output power before the amplifier starts to clip.
That is what I have been trying to communicate.
Matt Rowland,
With the 44 Posts so far, I do not remember . . .
Did you ever listen to the amplifier at moderate volume (staying in the Class A region)?
I would be surprised if it did not sound real good at that volume.
And I would bet even in AB1, it sounds OK, instead of some of the solid state amps that have real sharp clipping characteristics.
With the 44 Posts so far, I do not remember . . .
Did you ever listen to the amplifier at moderate volume (staying in the Class A region)?
I would be surprised if it did not sound real good at that volume.
And I would bet even in AB1, it sounds OK, instead of some of the solid state amps that have real sharp clipping characteristics.
No, I haven't listened to it yet! I wanted to get things working properly before trying it out. With all the comments, I've learned a lot so far. Cheers. Matt
Here is Thd% report of various OT impedance (7k 6k 5k 4k), best around 6K:8.
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tikiroo. Yes, those secondary resistances are a mistake, I was misreading previous notes. They are around 0.1R per secondary.
Koonw. Thank you for the sims. Useful references.
Koonw. Thank you for the sims. Useful references.