problem with jsx/412 also

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dartvader
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problem with jsx/412 also

Post by dartvader »

Ok so i have a peavy jsx and its 412 cab and for some reason the 3 speakers sound kind of muffled (like you would put a blanket it over it) but for some reason the bottom left speaker sounds fine so i hook up another known good amp and i plug it in and it sounds fine through it. so i was wondering if i were too hook up a 212 cab up too it would it work ok? (as in not muffled sounding) btw the preamp tubes are pretty old so it might be the culprit on why it sounds muffled thanks!

also the crunch channel on the amp sounds a bit low forgot too mention that
Stevem
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Re: problem with jsx/412 also

Post by Stevem »

There is no sane logical reason for only one speaker to sound normal with your JSX , and as you proved out the issue lies with that amp, and it could be due to the preamp tubes, power tubes, a poor connecting tube socket or even a bad / poor connection at the Amps speaker Jack!
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dartvader
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Re: problem with jsx/412 also

Post by dartvader »

Stevem wrote:There is no sane logical reason for only one speaker to sound normal with your JSX , and as you proved out the issue lies with that amp, and it could be due to the preamp tubes, power tubes, a poor connecting tube socket or even a bad / poor connection at the Amps speaker Jack!
yeah its really odd that the bottom left speaker if i were too use my jsx that it would work fine just the top left top right and bottom right would sound kind of muffled if i put a microphone in front of them its just i have a gig Saturday band rehearsal tonight and i was going to see how if it would sound okay with my 212 cab :)
vibratoking
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Re: problem with jsx/412 also

Post by vibratoking »

dartvader wrote:
Stevem wrote:There is no sane logical reason for only one speaker to sound normal with your JSX , and as you proved out the issue lies with that amp, and it could be due to the preamp tubes, power tubes, a poor connecting tube socket or even a bad / poor connection at the Amps speaker Jack!
yeah its really odd that the bottom left speaker if i were too use my jsx that it would work fine just the top left top right and bottom right would sound kind of muffled if i put a microphone in front of them its just i have a gig Saturday band rehearsal tonight and i was going to see how if it would sound okay with my 212 cab :)
I don't think you need anyone to tell you if it's going to sound OK with your 2x12 cab. You tell us.

I think there is a sane, logical reason, you just haven't found it yet. :P I would focus on the wiring difference between the working and not working case. I can't think of a sane, logical reason for this to occur IF all the wiring inside the cab is doing it's job. The wiring must be bad.
Last edited by vibratoking on Thu Apr 09, 2015 4:47 pm, edited 1 time in total.
Electronic equipment is designed using facts and mathematics, not opinion and dogma.
dartvader
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Joined: Thu Apr 09, 2015 4:36 am

Re: problem with jsx/412 also

Post by dartvader »

well the main reason i would use the 212 over the 412 for Saturday is i was thinking it would not make my amp run as hard? and maybe it would make both speakers work instead of just 1? just too get me threw for my gig
vibratoking
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Re: problem with jsx/412 also

Post by vibratoking »

3 speakers blanketed and 1 sounds good? I seriously doubt the amp can do that. How is the cab wired? What should the load be? What do you measure?
Electronic equipment is designed using facts and mathematics, not opinion and dogma.
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Structo
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Re: problem with jsx/412 also

Post by Structo »

I agree, sounds more like a speaker or cab problem.
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dartvader
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Re: problem with jsx/412 also

Post by dartvader »

it just dosent make sense that i could use a different amplifier and my cab would sound fine :/
vibratoking
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Re: problem with jsx/412 also

Post by vibratoking »

dartvader wrote:it just dosent make sense that i could use a different amplifier and my cab would sound fine :/
I agree. Please refer to my earlier post. What are the differences in the wiring? And what do expect and what do you measure in each configuration?
Electronic equipment is designed using facts and mathematics, not opinion and dogma.
dartvader
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Re: problem with jsx/412 also

Post by dartvader »

vibratoking wrote:
dartvader wrote:it just dosent make sense that i could use a different amplifier and my cab would sound fine :/
I agree. Please refer to my earlier post. What are the differences in the wiring? And what do expect and what do you measure in each configuration?
im not sure how to measure that well how exactly would i do that? i do have a multimeter but im not very familiar with electronics lol but i can solder a little bit.
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M Fowler
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Re: problem with jsx/412 also

Post by M Fowler »

I suspect the 3 speakers are bad or the wiring inside that 412 has come loose/someone was in there and messed things up maybe.

Hookup the 212 cab and give it a try by selecting the proper impedance load of the 212 cabinet on the back of your JSX head the slide switch 4/8/16.

If the 212 cabinet is not marked then insert speaker cord into the 212 cab jack and measure ohms off the 1/4 plug on the other end of that speaker cord. Ohms is not correct for impedance but will give you a ball park total impedance of that 212 cab.
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