On My Old Gibson GA40T Amp.....

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zozoe
Posts: 249
Joined: Tue Dec 10, 2019 5:39 am

On My Old Gibson GA40T Amp.....

Post by zozoe »

Greetings... off of the OT are the speaker leads, one green, one black.....Does it not matter which is + or -, & it's just a matter of being in phase with any other amp I may simultaneously be using?
Thnx folks!!
TUBEDUDE
Posts: 1864
Joined: Thu Jan 04, 2007 5:23 pm
Location: Mastersville

Re: On My Old Gibson GA40T Amp.....

Post by TUBEDUDE »

No problem on this amp as there is no global feedback.
Tube junkie that aspires to become a tri-state bidirectional buss driver.
DenDanger
Posts: 63
Joined: Fri Mar 16, 2007 9:27 pm
Location: Cincinnati

Re: On My Old Gibson GA40T Amp.....

Post by DenDanger »

On my GA-20 RVT the green is +. As well as a Kalamazoo Mod. 2

Being in phase with another amp you connect along side depends on the number of preamp stages of each amp.
On a wet/dry rig I use a recycled s/s slave amp that I use for my wet amp. My dry amp is tube.
When I connected both amps in parallel the speakers were out of phase so I installed a polarity switch on the s/s speaker to be able to invert the polarity.
The reason I installed a switch rather than just switching the speaker wires is because I had a switch on hand (quicker to test).
After trying a few different configurations, presently I tap off the dry amp speaker with a 40 dB pad into the wet effects and wet amp. Polarity reversal not needed here, but it’s available at the flip of a switch.
You can typically tell when you are in phase where you get the most bass response(I play recorded music when I am testing)

Good luck,
Denny
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