Steelaire combo amp with 2 TT-12 speakers

[Nick Holden]

Anybody using a Steelaire Combo amp Help!!! Can I use 2 separate cabs with TT-12 speakers one plugged into extension speaker 8ohms, and the other into internal speaker 4ohms and not hurt anything??? The TT-12s are 8ohms. Thanks for any info.

[Dave Diehl]

I talked with Pat Quilter about this and he told me that.. The Steelaire is intended for one or two 4-ohm speakers. A single speaker draws up to 200W and should be connected to “INT”. A second speaker should be connected to EXT. Dual 4-ohm speakers split the power evenly. If one of them is 8-ohms, it will draw 1/3 the power (66W) and the 4-ohm will draw 2/3 (133W). It won’t matter which jack each is in. When the second jack is used, a contact is lifted that reduces the optimum output impedance to drive the heavier load. The amp is quite “forgiving” about impedance, will generally deliver the same power over a wide range, and the only effect of mismatches will be minor changes in tone.