Adding another "ohmage" to an amp.

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Adding another "ohmage" to an amp.

Post by Timi »

Say I had an amp that can only be run at 2 or 4 ohms, how hard would it be to change the transformer and any other parts to also make it work at 8 ohms?

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Re: Adding another "ohmage" to an amp.

Post by GrantB »

Timi wrote:Say I had an amp that can only be run at 2 or 4 ohms, how hard would it be to change the transformer and any other parts to also make it work at 8 ohms?
What amp? The O/T might have an 8ohm tap tucked up it's arse maybe?
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Post by Timi »

Marshall VBA400.

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Post by DC4 »

You could put an 8 ohm speaker on a 2 or 4 ohm output, you'd loose a little power, well about half, but not hugely noticeable volume wise.
Or simpler, put 2 x 8 ohm speakers on (in parallel) and voila! there's yer 4 ohms...
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Post by Timi »

I've heard lots of mixed opinions on running an amp on 4 ohms with an 8 ohm cab, most people seem to think its a bad idea and puts strain on the transformer.

I have a 4 ohm cab too, which is what I would use it with most of the time. Sometimes I want to use my smaller cab or I play at shows where I am using someone elses cab, usually 8 ohms.

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Post by chrls »

I'd say most amp transformers are built to handle things like running 8 ohm cabs off a 4 ohm head. It really depends how you thrash it.

It's just like tools...they're built with the expectation that idiots are going to misuse them. I assume some amps are built that way.
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Post by Kristie »

chrls wrote: It's just like tools...they're built with the expectation that idiots are going to misuse them. I assume some amps are built that way.
I sure hope mine is :lol:

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Post by ash »

Timi wrote:I've heard lots of mixed opinions on running an amp on 4 ohms with an 8 ohm cab, most people seem to think its a bad idea and puts strain on the transformer.
I'd be hesitant too. Definetly a fatal idea to run too low an impedance cab, but too high an impedance, while not fatal isn't what the designers had in mind. It will sound different too, since it forces the power tubes into a different part of their operating range.
It's just like tools...they're built with the expectation that idiots are going to misuse them. I assume some amps are built that way.
Thats a dangerous assumption. Most consumer products are designed to make it through their warranty period for the lowest cost possible. They're generally not doing anyone any free favours for the sake of a few boneheads who want to thrash it to death.
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Post by Timi »

It doesn't really matter now, I've come to my senses and realised a 400 watt amp is just silly.

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Post by thehenderson »

Timi wrote:It doesn't really matter now, I've come to my senses and realised that having a moustach entitles me to mismatch ohmage whenever I see fit
That's the kind of power it gives you

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Post by Rog »

It doesn't really matter now, I've come to my senses and realised a 400 watt amp is just silly.
Heresy! Wash yer dang mouff out!! :)

I so want to remove this thread, 'cos I choke everytime I see the word 'ohmage', its as offensive to me as 'amperage' or 'light bulb'.
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Post by stark »

Rog - I know that that "ohmage" = impedance - what's the correct term for "amperage"?

you're still good with watts > wattage, volts > voltage, garb > garbage? :)
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Post by Timi »

Rog wrote:I so want to remove this thread, 'cos I choke everytime I see the word 'ohmage', its as offensive to me as 'amperage' or 'light bulb'.
Note these happy little fellows around the bad word ""

I will not take offence if you change it to "ohm setting" or "impedance". 8)

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Post by Rog »

LOL- don't worry about it, mate. I just like to have fun.

amperage => current in my world, but what the hell would I know, I'm old!!

'ohmage' is more fun anyway.
No its not - I hates it, I does
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Last edited by Rog on Fri Sep 15, 2006 10:16 am, edited 1 time in total.
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Post by stark »

"leveage" used as a verb annoys me. :x (it's in the dictionary as such, though)
Rog wrote:what the hell would I know, I'm old!!
Exactly :wink: .

Employ teenagers while they know everything!! :lol:
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