I have a blown Ampeg ba210 v2 that I pulled the head out of and rewired so that the wires that come from the speakers go to what used to be the external speaker jack. I hope to use this as a 2x10 extension cab for my rumble500 combo. I have an old multimeter and I cannot get a reading off the ampeg to make sure it's still wired correctly at 8ohms. I didn't change anything at the speakers and I can't think of any reason it wouldn't be 8ohms. I hooked it up to the fender for a quick test run and it works and sounds pretty good I just don't want to risk blowing up the fender if something is wired wrong in the ampeg. Just looking for some confirmation that I should be good to go.
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Turning combo amp into extension cabinet.
- Thread starter Scott Janas
- Start date
Be 100% sure there is absolutely no connection whatsoever to the Ampeg circuitry except the speakers. I would reccomend physically removing the amp and adding a connector to the cab.
What is the impedance of each speaker and how are they connected to each other?
What is the impedance of each speaker and how are they connected to each other?
The head is completely removed. I left only the rear panel with the jack on it.. The original setup was 2 16ohm speakers wired in parallel. I did nothing to this other than clip the wires from the harness where they went into the head and attach them to the speaker jack.
It will read a little below 8 ohms on a DMM. Impedance isn't resistance even though they use the same unit of measure. Sounds like you've got it squared away. Pics?
My multimeter isn't giving me any reading at all but its also from 1975. Pics aren't great but red and black coming up from speakers into the space where the head was spliced to the wires coming from what was the external speaker out.
Are you sure those red/black wires weren't power to the amplifier?
If each speaker is 16 ohm confirmed, and the amp is gone; you really aren't too much at risk. The possible wrongs are either out of phase (which you would notice as a reduction in low end response most likely) or series, which would result in a 32 ohm extension cab. Seems to me you should be ok.
Edit
Of course it still depends on the Fender and Ampeg speakers and box tuning playing nice with each other's tone and voice.
Edit
Of course it still depends on the Fender and Ampeg speakers and box tuning playing nice with each other's tone and voice.
if you never touched the wires like you said inside the cabinet.
should be good. its basically red to red and black to black splice.
for the most part that doesnt matter either. unless used with another cab someday.
or like you are with the combo.
just check both have forward motion
id say most speakers are wired for forward motion on the positive.
but if you ever needed to change polarity obviously you just reverse the connections you made.
hope that is not confusing
for the most part you are good, and a 2x10 8 ohm is very nice.
as for the dead ampeg, you used to be able to get new boards easily. now im not sure
the switch mode power supply dies on these things often.
and the whole board gets replaced
should be good. its basically red to red and black to black splice.
for the most part that doesnt matter either. unless used with another cab someday.
or like you are with the combo.
just check both have forward motion
id say most speakers are wired for forward motion on the positive.
but if you ever needed to change polarity obviously you just reverse the connections you made.
hope that is not confusing
for the most part you are good, and a 2x10 8 ohm is very nice.
as for the dead ampeg, you used to be able to get new boards easily. now im not sure
the switch mode power supply dies on these things often.
and the whole board gets replaced
Yeah, I had it fixed once and it died again so I thought I'd try this. Running it as an extension cab with the Fender gives me the full 500w from the rumble. I haven't cranked it too much yet but they seem to be playing nice.
Oh dang.
Yeah, id be done with that amp for sure then. And the most valuable portion is the parts working. a Straight forward 2x10 8 ohm cab
sweet
come on now, crank it up and rattle the windows, you know you want to...
Great! Not only that, you have a built in two space rack where the head was. Rackmount gear is cheap these days, have some fun. Aphex Aural Exciter and a multi effects unit would be nice.
I did the same thing with an old Yorkville BM200 15" combo amp. The head died so I removed it, added a jack plate, and gigged it as an extension cab until I blew the 200W driver. I replaced the driver with a 1000W eminence and now it's unkillable! +1 on keeping ahs using the parts that still work.
I wish I had looked at the drivers to see what they were rated at. I don't feel like gutting it again and I can't find any info other than they use eminence though maybe slightly underpowered compared to after market. The head was rated at 450w so I feel like the speakers should survive the 500w from the fender. I suppose at this point it's not much of a loss if they blow down the road.
