I've got a guy who's telling me I can disconnect the internal speaker from my combo's power amp and it won't hurt the output transformer as long as I have a cab running out of the extension speaker jack. Is this true ? It's an old tube amp.
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Quick Extension Cab Question
- Thread starter LevinFan
- Start date
Which old tube amp? It would be possible, but you'd need to match the impedance of the combo's driver to the output transformer.
It also depends on how the speaker connections are wired. Bottom line is that , yes, you can run the combo with an external speaker instead of the internal one. The caveat is that you gotta know how the amp is wired so you can present the correct load to it. If the external speaker jack is wired in parallel with the internal speaker you should be OK to just unhook the internal one and hook up an external load of the correct impedance.
But,if it's like some Fenders where the external speaker jack is a switching jack that selects different transformer taps, then you'll have to be careful of how you do that.
John
But,if it's like some Fenders where the external speaker jack is a switching jack that selects different transformer taps, then you'll have to be careful of how you do that.
John
ok, fair enough. RB, it's an old Sano amp.
I just got it back from a tech last week, and I asked him to determine all of this, and I couldn't get a straight answer from him. The amp has a 15" in it, 8 ohms, and it once had two 8's as well. I know the 8's ran off the 15, but don't know if they were wired series or parallel, or what ohms they were. There is a large cap still there with remnants of the wiring.
Best I could get out of him was the amp could be run with an 8 or 4 ohm load, but that doesn't answer my questions in regard to using the extension cab jack.
So, I'll guess I'll just remove the wiring from the internal speaker and solder a phone jack on it and run the extension cab that way.
The amp sounds great with the 15, but the cab resonance is beating the tubes to death at higher volumes, and the springs in the reverb tank rattle. That's why I want to run extension cabs only.
I don't know if the questions can be answered by looking at a schematic, but here it is.
http://www.schematicheaven.com/bargainbin/sano_30_50_WRT.pdf
I just got it back from a tech last week, and I asked him to determine all of this, and I couldn't get a straight answer from him. The amp has a 15" in it, 8 ohms, and it once had two 8's as well. I know the 8's ran off the 15, but don't know if they were wired series or parallel, or what ohms they were. There is a large cap still there with remnants of the wiring.
Best I could get out of him was the amp could be run with an 8 or 4 ohm load, but that doesn't answer my questions in regard to using the extension cab jack.
So, I'll guess I'll just remove the wiring from the internal speaker and solder a phone jack on it and run the extension cab that way.
The amp sounds great with the 15, but the cab resonance is beating the tubes to death at higher volumes, and the springs in the reverb tank rattle. That's why I want to run extension cabs only.
I don't know if the questions can be answered by looking at a schematic, but here it is.
http://www.schematicheaven.com/bargainbin/sano_30_50_WRT.pdf
