15 an 8 ohm speaker in same cab?

[Oddvar]

Hi.  Is it possible to have a 15 ohm and a 8 ohm 25w speaker in the same cab in a Bassman 59?  I hav an old Greenback Pre Rola, 15 ohm, that I wanted to test?

[sluckey]

Sure. Just connect to your 5.2Ω or 23Ω OT tap for maximum output power. 

[Oddvar]

  ok, I'll rewind the transformer right away.  But seriously, would it be ok?

[PRR]

For test, sure. 4 Ohms is close for 16||8.

However the 8 Ohm job will take more power and be louder than the 16. Not sure what you are trying to test.

For the original purpose of a 2-speaker cabinet, THROWing across a large club, you want the two speakers identical and working in unison. Even if same brand/model, a 16 and an 8 won't take the same power and give equal output.

Many people do use mixed pairs for a different sound.

[Oddvar]

I just want to test it. I have to Scumbacks in the cab now, they sound a bit thin.  And since I have this old Greenback on the shelf, thought I try, just checking, not for permanent use.

[12AX7]

However the 8 Ohm job will take more power and be louder than the 16.

This^^^

I tried it once and the lower one was louder to the point the other one wasn't really heard. Sounded like the one speaker alone.