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Old 02-10-2018, 06:47 PM   #1
grousehunter49
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Default Peavey Classic 30

Classic 30 exturnal speaker says 16 ohm minimum.I have a 4x12 8 ohm..can I use this 4x12 8 ohm cab.
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Old 02-10-2018, 06:52 PM   #2
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I wouldn't! that's gonna suck double the current then, could blow your amp.
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Old 02-10-2018, 07:25 PM   #3
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I'm pretty sure that Peavey has a website that will allow you to contact them about technical matters. Try that first. You'd be surprised at what kind of speaker configurations will work. With that said, the previous post is dead on when they tell you that the amp will try to deliver twice the power if you connect half the load. I once got away with hooking a Fender Frontman 25 watter up to two 12 " speakers. It sounded great but I never allowed the master volume to go above 12 o'clock. If I had turned it up to full volume, it would have tried to deliver 50 watts and that would have caused the transistors to over saturate and that would have caused thermal runaway and that would be nuclear meltdown to the amp and then I wouldn't be able to turn it back down and then I'd have to jerk the cord out of the wall socket to turn it off, and then the smoke would fill the room, and then I wouldn't be able to see and couldn't find my phone to call the fire department, and then I'd be overcome by the smoke and die. But I digress.
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Old 02-10-2018, 07:26 PM   #4
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hahha wow that's quite the story there LOL
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Old 02-10-2018, 09:03 PM   #5
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Quote:
Originally Posted by grousehunter49 View Post
Classic 30 exturnal speaker says 16 ohm minimum.I have a 4x12 8 ohm..can I use this 4x12 8 ohm cab.
Amplifiers should not be driven into a load that has a lower resistance than their rating.

Step 1: Grab a screw driver, open the back of your 4x12 and see what the speakers list as their resistance. Draw a quick diagram of how they are wired (series/parallel) and take a pic so you don't have to remember where everything goes.

Step 2: Now that you know the resistance of each individual speaker, change the wiring so that the result is 16 Ohm...

Series for cumulative:



Parallel for division:



Note: Speaker impedance is measured in AC resistance. You cannot simply hook up a DC multi-meter and get an accurate impedance measurement.
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Old 02-10-2018, 09:52 PM   #6
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hey weird I did a post similar to the one above, now it's gone, freaky!
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Old 02-10-2018, 09:55 PM   #7
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Running a 16 ohm load alongside an 8 ohm load will present the amp with about a 5.35 ohm load, and that will toast your output section real quick.

You will need a second 16 Ohm loaded cab to present the amp with an 8 Ohm load that the power section will tolerate.
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Old 02-10-2018, 10:10 PM   #8
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Just checked a C30 schem...

You can use your 8-ohm cab standalone without modification, but must unplug the internal speaker in your C30 first.
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Old 02-10-2018, 10:59 PM   #9
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Default Peavey Classic 30

Ok.you mean pull the two clips of the speaker...also. my Orange micro terror says min 4 ohm can I use the 8 ohm cab? I am,,should I?
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Old 02-10-2018, 11:14 PM   #10
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Yes, you can use an 8 Ohm cab on the Micro. I used one on mine.
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