Silvertone 1482: 4 ohm or 8 ohm OT?

[capnjuan]

A friend of mine (really!) is considering a Silvertone 1482 but putting an 8 ohm speaker on it. The public domain schematic shown below:

http://i142.photobucket.com/albums/r106/capnjuan/silvertone1482a.jpg

Suggests that there are 4 and 8 ohms taps however, as drawn, only the 4 ohm taps are 'connected'; am I reading this right? Will he go to tone jail if he hangs an 8 ohm speaker on 4 ohm taps? Assuming I have this right, anyone have any suggestions for a 4 ohm / 12" speaker?

Thank you.
John

[Old Tele man]

...most SEARS amps, like Fender amps, used 8-ohm speakers, so if single speaker then probably 8-ohms OT, if dual speakers (in parallel) then probably 4-ohms OT.

...also, remember the general "Rule-of-Thumb" for vacuum tube speaker ( Z ) loads, which is: "...anything between HALF-Z and TWICE-Z is usually OK..." with slight reduction (~15%) in output power from 'optimum'-Z.

[capnjuan]

... so if single speaker then probably 8-ohms OT, if dual speakers (in parallel) then probably 4-ohms OT. No; single speaker only.

...also, remember the general "Rule-of-Thumb" for vacuum tube speaker ( Z ) loads, which is: "...anything between HALF-Z and TWICE-Z is usually OK..." with slight reduction (~15%) in output power from 'optimum'-Z. Suggesting that even if 4 ohm taps only, not going over a cliff with an 8-ohm speaker?

Thank you Old Tele Man.
John

[hasserl]

I have a speaker from a 1482 hanging on the wall here. I just pulled it down and measured the DC resistance at 4.3ohms. FWIW, I installed an 8 ohm speaker into the amp this one came out of, and it sounded great. I don't know if it was a perfect load match, but it sounded damn good, which is what's important IMO.

[doctorx]

1482's came with a 4 ohm speaker attached to a 4 ohm tap.

The unused tap on the OT is an 8 ohm tap, use it if you have an 8 ohm speaker.

[capnjuan]

Thank you all very much for your replies. John