Using PP output transformers for single ended amp

[SHiFTY]

What is the difference between PP and SE output transformers? I have a couple of PP ones but I am eying up a couple of SET projects....

Or, would it be possible to put a couple of transformers in series for a higher power rating in a mono amp? I am also thinking of using these for a PP subwoofer amp.... The trannies are rated at 10W, would I be able to rock 20W from a pair in series? Or would that cause "issues"?

So many options

[HDTVman]

Hi ShiFty

There is a big difference in the core of PP and single ended transformers. Single ended transformers have a controlled gap in the core to prevent core saturation caused by the DC current in the primary. PP trans. don't thave this gap. PP transformers are designed with a center taped primary and depend on equal and opposite curent flow in each half of the primary to null out the magnetic field of the idol current. This keeps the core from saturating.

For the sub project use then in parallel, not series. That should work OK.

Good luck; Bruce

[dice45]

ShiFtY,

HDTVman is right, PP-Xformers do not have air gaps. This means the trannie which can handle 50Watt PP maybe can handle 500mW SE, probably only 50mW.

My hint: keep the PP trannie for a future tube subwoofer amp project and buy a SE trannie suiting your needs.
Or build a fullrange PP amp.

[Tom S.]

You can use the PP transformer for a parafeed SE circuit. Going further, a PP transformer would be a better choice for the parafeed circuit when compared to using an airgapped SE transformer as the PP transformer will have a higher inductance.

Tom §.

[planet10]

Originally posted by ShiFtY
Or, would it be possible to put a couple of transformers in series for a higher power rating in a mono amp? I am also thinking of using these for a PP subwoofer amp.... The trannies are rated at 10W, would I be able to rock 20W from a pair in series? Or would that cause "issues"?

Bill Perkins has a paper on Twinning PP OPTs that might be helpful.

dave