#1
So I was playing a moment ago, and then my volume just started decreasing until there was none, and theres a burning rubber smell from my amp. But I turned it off and on straight after and it worked...(I only played it for a few seconds because I was worried). But the tubes were red hot and so was the casing at the back. Whats wrong? I have an 8Ohm V30 as the speaker and it's rated at 16Ohms, that's the only thing that's modded. I know that it's wrong, but I e-mailed the technical department at Peavey and they said it would just run hotter than normal and that there would be slightly decreased tube life. It's a Peavey VK112, Please Help!
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#2
maybe it overheated, or the tubes died. but if it works again then the tubes are okay i would guess.

i would say it overheated. maybe aim a fan at the back of the amp?
Does anyone remember laughter?

Manuel, please try to understand before one of us DIES.

my gear:

Gibson LP Standard
Epiphone SG
Classical guitar
Peavey ValveKing 112
Marshall MG15
BOSS ME-50
#5
I'm not really an expert, but I'd say no (by the looks at least, maybe they're starting to go but you can't see it from the outside?). It's normal to have some browness/darkness at the end, don't know about the middle. At least sometimes when they blow there's white at the tip I believe.
Quote by Lunchbox362
This thread if fail in almost every way imaniganable.
#6
Quote by forsaknazrael
Wait, what's the deal with the speaker? It's an 8 ohm speaker, but your amp needs 16 ohms??


Yeah. I e-mailed Peavey because I had bought and installed it accidentally. Here's the E-mail:

Quote by PeaveyTechnicalGuy
Hello Lee,

The amp is designed to use a 16 ohm speaker, and that is what is
recommended.
You can use an 8 ohm speaker, but the amp will run a little hotter and
your
headroom will be reduced, along with slightly reduced tube life.


Regards,
Roger Crimm
Regional Service Manager
Peavey Electronics


And that's what he said.
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#8
Are you sure? My dad's an electrician and he said you can run them the way round I had it, but NOT the other way round.
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#9
Quote by forsaknazrael
Well, he's wrong. You can't mismatch speakers like that at all.

Wow! That' terrible advice. You can potentially fry the amp's transformers like that. You can use an 8 ohm amp with a 16 ohm speaker, but not the other way around.

Never mismatch impedence in a tube amp.
#10
I found this site...http://wolfstone.halloweenhost.com/Audio/spkimp_SpeakerImpedanceMatching.html#CanYouSurviveImpedanceMismatch

Can you survive impedance mismatch?
I am convinced that the most common question is not "how can I properly match amplifier and speaker impedance?", but "how much of an impedance mismatch can I get away with before something explodes?"

According to legend and conventional wisdom, solid state (transistor) amplifiers can drive higher impedances than their rating demands. So a transistor amp with a label saying "4-ohm" will drive 4, 8, and 16 ohms with no troubles. You can go up but not down. Don't try 2 ohms.

Older legends say that tube amplifiers can drive lower impedances than their rating demands. So a tube amp with a label saying "8-ohm" may drive 4 and 8 ohms. You can go down but not up. Don't try 16 ohms. And never run a tube amplifier without speakers attached. Other legends of the tube age say that any attempt to use a tube amp with speakers of different impedance may cause damage to the amplifier.

I have not tried either of these combinations, so don't blame me if it causes problems.

Honestly, you are better off with a proper match. Just because your tube amp with 8-ohm output survives driving a 4-ohm speaker doesn't mean that it likes driving that load. You are probably reducing the life time of the amp.


This worries me.
This comforts me.
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#12
I have no absolute knowledge on this issue (impedance thing I mean), but I've read about possibly using close impedances (don't remember if it was up or down). However, I remember someone mentioning something about best not mismatching impedances with tube amps - something to with the somewhat irregular nature of tubes or something.
Quote by Lunchbox362
This thread if fail in almost every way imaniganable.
#13
Quote by forsaknazrael
^Get the right speaker. Does the amp still work right now? I mean, don't turn it on...but..


Agreed. But you can do it to some degree.


Well, yeah it does. Exactly as the Peavey Guy told me it would. I think Peavey made their Transformer forgiving enough that it could run an 8Ohm speaker if it had to, or so someone from my first thread on this said. I think it must have just overheated because it's running hotter, I was playing for a long time and its right next to a radiator (I've moved it now though). Isn't there any way I can make it run on 8Ohms? I really don't want to change the speaker again, I paid £40 for this one. Someone mentioned plugging a dud jack into the External cab socket so that the speakers are put to series mode, except there isn't another speaker. I don't think that this would work though because when you plug an external cab in it turns off the speaker I already have in the combo.
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#14
I don't think you can change the impedance of the speaker (or do anything about that), sorry.
Quote by Lunchbox362
This thread if fail in almost every way imaniganable.
#15
go to a guitar shop and ask a pro, or get them to fix it for you.
Does anyone remember laughter?

Manuel, please try to understand before one of us DIES.

my gear:

Gibson LP Standard
Epiphone SG
Classical guitar
Peavey ValveKing 112
Marshall MG15
BOSS ME-50