Knoppson Tube HiFi

Lundahl Output Transformers, LL1663 and LL1691B

Data [drawings]:

LL1663: 300B Push-Pull Class A Amplifier
Uin<450V RMS@30Hz
LL1691B: 845 Push-Pull Class A Amplifier
Uin<1830V RMS@30Hz

LL1663 also works for KT88/6550 UL taps (33%)

These fantastic C-core transformers are the best in the world and they are made in Sweden by Lundahl. Both of the
above transformers are intended for Push-Pull use only, this while they have no or a too small an air-gap for use
in other configurations. I only build Push-Pull amplifiers so for me this is no problem but it should be pointed
out. I will probably never use any of these transformers so if anyone want to buy a couple, feel free to ask.
The reason for this that I love the transformers I've already designed by my own. These are far worse than Lundahl
of course but they suit my needs.