The Last Bass Outpost
Gear Discussion Forums => Bass Amps & Effects => Topic started by: SKATE RAT on January 28, 2010, 07:01:43 AM
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i just got an old Peavey 4X12 cab that runs at 4 Ohms. can i rewire it to run at 8 Ohms? that way i can run 2 8 Ohm cabs? or can i run a 4 and an 8 together?
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A friend sent me this link. It's pretty cool and might help you out.
http://www.bcae1.com/spkrmlti.htm
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ok,i got it. thanks for the link.
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or can i run a 4 and an 8 together?
That's 2.66 ohms and is usually OK for most tube amps that can handle 4 ohms. The fact that the speakers are hooked up in series/parallel internally in the cabinets means that the actual voltage drop will occur at differing frequencies. Going lower than rated for a tube amp is usually fine. In fact most of them short their output to ground when no speaker is connected as a safety measure because... if you present too high an output impedance to a tube amp (or output transformer coupled s/s amp) the transformer turns into a large feedback voltage generator and you get to kiss your output tubes, their sockets, and everything else in the immediate proximity goodbye.
An easy way to tell if your load is too low for a tube amp is if the amp starts distorting when you connect the lower than rated load, but sounds fine at a rated cabinet or the metal gray parts inside tubes start to change color and turn a shade of red or yellow. Going lower than rated does age the tubes much faster, but they live a hell of lot longer than most people give them credit for anyway. Usually if you're giving a tube amp too low a load and it's hurting it, the main fuse will pop before any major damage occurs.
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That's 2.66 ohms and is usually OK for most tube amps that can handle 4 ohms.
But not solid state amps, right?
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But not solid state amps, right?
Correct.
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It's not that they are solid state; it's that most solid state amplifiers don't have an output transformer to feed back. There ARE solid state amps with OT's, but they are mostly very old and not common, however, there are current examples, the Warwick Jonas Hellborg being one.