#1
is it any safer/unsafer running a 4 or 8 ohm cabinet of an amp. Was going to build 2x12 rated 8ohm but speakers were 250bucks each. Can get two for 199 each of ebay but there 8ohm each. so it would have to be a 4ohm rating. dont have a socket for 16ohm so thats out of the question.
#2
well if ur cab can get 16 ohms put into it, then ur OK running 4,8 or 16 ohms outta ur amp my MG puts out 8 ohms, and i have it hooked up to my behringer cab which accepts 16mom, and it works. Just make sure its not the otehr way around i.e. amp puts out 16 can takes in 8, thats a nono
#3
What? Learn some basic punctuation and grammer please. Unsafer isn't actually a word, for the record. I don't believe that it is safer or "unsafer" for either. I'm running 8ohms, but it depends on what kind of speakers your head is going to be played through.

Hey guys! I just started playing electric guitar should I get a Gabson Lay Pall or a Femdor Startokaster. I like the picks on the gabsons but i like how sweet femdors look. Beforre i get a gabson what company makes them?
#4
Depends on the rating of the amp. If it's 4ohm, then you need to use a 4ohm speaker, or 2 8ohm speakers in parallel. If it's 8ohm, the combined resistance also has to be 8ohms. So you could put 2 4ohms in series, or an 8ohm alone, or 2 sets of 2 8ohm speakers in parallel, the sets being in series.
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#5
actually, even if you miss match impedances, they'll generally be tolerant by a factor of 2.

It's "safe" to run a 2, 4, or 8 ohm cab on a 4 ohm amp, safe for a 4, 8 or 16 ohm cab on a 8 ohm amp, and 8, 16, 32 ohm cab on a 16 ohm amp.

Although, if you don't match impedances, you won't have maximum power transfer.
#6
its a combo amp with 1x4ohm line out and 1x8ohm line out. I can get two 16ohm speakers and wire them parrallel for an 8ohm rating but these speakers were 250bucks each. For 199 bucks each i can get 4ohm vintage 30s from ebay and wire them parralel for a 4ohm rating. Its cheaper this way, but what i want to know is does a 4ohm line out put your amp under more stress, or will it be just the same as with an 8ohm line out. Its just that the guy in the tutorial said 8ohms is best, but why.?
#7
Actually, if you run 2 4ohm speakers parallel, the load is 2ohms.
Posers are like punks, except they do it for fashion

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#8
sorry i meant in series. Just not having good day. Have two brocken fingers and wont be able to play guitar for 4-6weeks, really ****ed off about it. my minds not quite swithched on.
#9
Quote by Dyaxe666
well if ur cab can get 16 ohms put into it, then ur OK running 4,8 or 16 ohms outta ur amp my MG puts out 8 ohms, and i have it hooked up to my behringer cab which accepts 16mom, and it works. Just make sure its not the otehr way around i.e. amp puts out 16 can takes in 8, thats a nono


This isn't as applicable with solid state amps.

4 ohms will work fine with the applicable tap on your power transformer.
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#10
You want to best match your cabinet impedance to your amp's output impedance. 8ohm is probably the best because of the 3 most common amplifier output types, 4, 8, 16 ohm output impedance, 8 ohm will be tolerated by all 3. You still want to best match the impedance for your amp.
#11
so then a four ohm setup in a 4ohm outlet would be perfectly matched impedence way? does this also mean i will get the most out of the cab? Also has anyone built a 2x12 with 12" vintage 30's. If so any reccomendations as to the size of the cab.
#12
Well, it wouldn't be PERFECTLY matched. I mean, the impedance of a 4 ohm speaker isn't exactly 4 ohms, it's usually something like... say 3.9 ohms or whatever. The point is, the closer the match, the better the power transfer. If the speaker is lower than the rated/recommended impedance, then the power transfer will be much less, if the impedance is higher, than it'll essentially "bounce" back some of the signal. (which is why not connecting a speaker and turning on a tube amp is BAD, cause when a speaker isn't connected, the impedance appears to reach infinity [open loop], so it'll bunk up your output transformer, and maybe more)

Lesson of the story?
If you have to mismatch your speakers, try to get them as close as possible. But never run an amp without a speaker.

But yeah, a 4 ohm outlet and a 4 ohm setup would be matched pretty nicely.