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jackrhein
02-27-2007, 07:45 AM
I want to use one d130 to replace the two 12" Jensens in my 1965 silvertone 1484 piggyback guitar amp. (It has two 6L6's in a push pull circuit, but I don't know how many ohms the amp is looking for) I don't know if I should use a 16 ,8 or 4 ohm speaker. The problem is that the amp is a little too loud for my requirements. I am running it on "1" which does not allow the amp to run at a level where the amp gets it best tone. Would a 16 ohm speaker allow me to run the amp at a higher gain (say 2 or 3) without blowing me out of the room? wil the higher ohm speaker change the tone, will it hurt the amp?

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Zilch
02-27-2007, 11:36 AM
What is the stated impedence of the Jensens?

Are they connected in series or parallel?

What's the manual say?

jackrhein
02-27-2007, 02:26 PM
the amp is looking for two 12" jensens wired in parallel for 4 ohm load

Zilch
02-27-2007, 02:50 PM
There's your answer, then. Tube amp experts may jump in here with more comprehensive intelligence, but in my experience, the output transformer wants that specific load.

Unless other taps from the transformer are available as options, that's what I'd use. I don't know that you're going to find a 4-Ohm D130, though....

subwoof
02-27-2007, 03:36 PM
the impedance mis-match going *up* in the load will not hurt the amp and will give you the volume "control" you want but be advised that the '130 family is VERY efficient and may be just as loud.

This mismatch was a favorite studio trick with large tube marshall amps that have a selector switch on the back.

Any frequency deviation will be magnitudes lower than the normal coloration the tube amp does to the signal anyways.

Remember that a guitar amp / speaker is a "producer" Most posters here are dedicated to the "reproducer" speaker systems....

sub