So there is a JC-120 on eBay going used for £250. Only thing is the right celestion speaker has been replaced with a Marshall speaker that the seller claims has better specs anyway. Is this something that will significantly change the sound of the amp and would it make the amp worth more or less in your opinion?
jc-120 is known for its amazing clean sound. putting a marshall speaker in there may make the sound less clean but it might make a unique sound and for £250, its a bit of a bargin
Perhaps I should ask for a sound demo. It's just the speaker for the power amp so I would have thought the sound wouldn't have been affected much.

But with it being modded, fewer ppl r gonna want it I guess, which means I wouldn't be able to sell it on if I don't like it.

(for once a question nobody can answer with "try before u buy" :P)
"Marshall Celestion speaker" could mean anything from a seventy 80 to a G12K100. The former would make the amp worth less the latter would make it worth more - and there's everything in between.
Gilchrist custom
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i have the stock roland speakers that were modeled after the JBL 75s (i believe) in my jc120, and i like them a lot. i thought about switching them out before but i don't really think it would be worth it right now. i really don't think Marshall speakers would do a jc any good, i would hear it first.
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Roland JC120

Quote by CaptainAmerican
I would recommend the marshal MG100

Very versatile and quality sound. It should treat you well