Lundahl LL1527 phase-splitter

[Klimon]

Is Lundahl LL1527 suited as input phase-splitter for a 'hifi' amp? Say 2V input signal and 6sn7 as load.

thanks!!

Simon

 

[KevinC]

The LL1527 will work, but there are other more suitable transformers in the Lundahl catalog. The LL1592 is the best choice with a mu metal core and the LL1690 is the best with a cobalt amorphous core. These can be used 1+1:1+1 and 1:1+1 (with the primary coils in parallel) for phase splitting.

 

[SY]

Whichever you use, do try to optimize the loading, taking into account the input and Miller capacitance of the 6SN7 and the source impedance of your preamp. Usually, diddling the value of the resistive load on the secondary and/or using a Zobel will greatly clean up the time domain behavior.

 

[KevinC]

But if you do endeavor to fiddle with loading, listen as you do it. Not all transformer loading networks that look good on the scope sound good to the ear.

 

[Klimon]

1527 suits my lack of budget best 😉
I'll keep the zobel idea in mind; thanks for the replies

Simon

 

[Shoog]

I would agree with SY, these babies can ring and overshoot like crazy. I have about 300K load on each of my secondaries, and that cleaned up the top end a load.

Shoog