TYPE AA Crossover Build

[henry4841]

https://critesspeakers.com/autotransformers.html

 

Data sheet for the 3636 autotransformer is at Bob Crites website.

[mboxler]

I'm definitely no expert, but...

 

Attached is a schematic of an adjustable Type A that I may build someday.  Ignore the 26uf cap on the output.  I changed the 3636 to show the taps in a clearer way.

In fact, you could put new labels on the 3636, changing...

 

5  to   +0 db

y  to   +1 db

x  to   +2 db

4  to   - 3 db

3  to   -6 db

2  to   -9 db

1  to  -12 db

 

The .2mh inductor and 10 ohm resistor should connect to a point on the board, not to the 3636.  You then need a wire with a quick disconnect.

Solder one end of the the wire to this point, and move the quick disconnect end  to +0 db, +1 db, or +2 db taps.

 

Run a wire from the positive side of the K-55 to another point on the board.  Again, you then need another wire with a quick disconnect.

Solder one end of the the wire to this point, and move the quick disconnect end  to -3db, -6db, -9db, or -12db taps.

 

Hopefully, this is a clear way to decrease the voltage to the K-55 in 1 db increments by "adding" the input tap to the output tap.

In the attached schematic, input is +0 db, output is -3 db, so the "sum" of the taps = -3 db.

 

I hope that was somewhat clear.

 

Mike

 

[Schu]

This is what happens when you change taps... and don't address cap values