Getting to see what a new OT will or wont do

[pjd3]

Hello,

Hopefully better late than never. I personally do not carry a high intuition to carry out a relevant comparison but, here are comparisons between the new MPS "oversized Deluxe Reverb" output transformer and the Shuang Meei that was replaced. I just did Primary inductance alone, then with the secondary shorted.

Straight primary inductance (no shorting of other windings) (LCR bridge settings @ 1Khz/1.00V)

1. Primary Inductance measured, alone:
MPS OT22PP Chuang Meei

Brown/Blue - 5.6H Brown/Blue - 6.413H
Brown/Red - 2.69H Brown/Red - 1.66H
Blue/Red - 3.00H Blue/Red - 1.65H


And here is applying the LCR bridge to Brown/Blue primary while shorting out each individual secondary tap with respect to secondary black common: (LCR bridge settings @ 1Khz/1.00V)

MPS OT22PP Chuang Meei
Primary measurement(with sec shorted)
(4 ohm tap) - 13.418mH (4 ohm tap) - 3.8mH
(8 ohm tap) - 11.12mH (8 ohm tap) - 7.7mH
(16 ohm tap) - 8.64mH (16 ohm tap) - 13.4mH

So, it appears that that there is an inverse increase/decrease relationship in leakage inductance between the new MPS OT22PP and the Chuang Meei. I wonder if that could be dictated by the "phase" relation between primary and secondary of the two OT's. Also, its very obvious that the leakage currents for my new OT are greater than the Chuang Meei by an order of 2-3 generally speaking. I cant know yet if this is actually indicative of the old Chuang Meei being a better transformer or, the amount of coils in each making that difference. (The LCR bridge was always set to 1Khz @ 1V). Perhaps someone who is more versed in transformers could answer that. Its probably helpful to remind that the new MPS OT22PP is toted as an Oversized deluxe reverb OT (25-30VA @ 6.6K ohms) and the Chuang Meei was chosen for a 40-50 watt 6L6GC PP Pair in a Bogner Alchemist. That was a very loud amp!

Thanks for bearing with me. Nothing really sticks out to inform me of anything I can assess, but, perhaps it will tell you something I can't see. The new transformer seems to have a little bit of a different EQ, and maybe a tad softer, but, then again. The whole NFB loop is configured very differently which probably negates any relevant comparison of tone/volume. On the new configuration with the new MPS OT, I put in a 3 position switch with 22K, 15K and No NFB. The 22K ohm setting I believe is what is hard wired in Sluckeys 6V6 plexi as that is the schematic I used as a guide.

Again, thanks for taking a look at this, I sure was curious if anything could be found.
Best,
Phil D