Kramer
Well-known member
I changed out a bad speaker(16 ohm) in a combo amp of mine and replaced it with a spare "15 ohm" Celestion.Will the one ohm difference do any harm to the amp?
Thanks,
Kramer
Thanks,
Kramer
dragonworks
Banned
Kramer said:
I have never seen a 15 ohm speaker.
Kramer
Well-known member
Re: Re: Guitar Amp Speaker Question
me neither until now.LOL...it's actually one out of a quad set of celestion greenbacks that were in an ampeg 4x12 cabinet.....15 ohm printed right on the back of the speaker....new one to me too.
dragonworks said:
me neither until now.LOL...it's actually one out of a quad set of celestion greenbacks that were in an ampeg 4x12 cabinet.....15 ohm printed right on the back of the speaker....new one to me too.
hixmix
Halibut, North Dakota
When the amp and speaker don't match ohm's the sound quality suffers. You'll get a thinner, tinny sound. I'm not sure about what damage it may do though. That extra or missing ohm has to go somewhere. Perhaps it might fry a circuit? Get yourself a 16 ohm speaker.
JMarcomb
New member
hmm.. its printed 15 ohm.
If you have a multimeter. hook the leads up and see what it reads.
I have a set of greensbacks and a set of vintage 30's and they show ~15.7 ohms.
compare the resistance to your others speakers... it might be the same.
If you have a multimeter. hook the leads up and see what it reads.
I have a set of greensbacks and a set of vintage 30's and they show ~15.7 ohms.
compare the resistance to your others speakers... it might be the same.
jake-owa
Banned
Kramer, I really don't think it will hurt anything. i recently got a replacement tweeter for my Alesis monitors and it was a 6 ohm instead of the 8 ohm that it replaced. It actually sounds a bit better and pipeline said it would be fine.
Come back to the cave Kramer.
Come back to the cave Kramer.
hixmix
Halibut, North Dakota
jake-owa said:
With tweeters, perhaps, mismatching ohms could be beneficial.
Kramer
Well-known member
Hixmix, JMarcomb, Jake-owa,
Thanks dudes!
I feel a little better now even though Hix thinks it might fry something.
Jeff,
I'll stick a multimeter on it and see what it reads.Im guessing it'll be a little over the 15 ohms that it says it is.
jake-owa,
I was thinking that it wouldnt harm it(I was hoping),but I wanted to make sure before I put very much more playing time into it.If pipeline said it would be ok for you to put a 6 ohm speaker in place of a 8 ohm then I'll trust his judgement.I should be ok with this speaker.
P.S.The cave is too hectic for me man.I dont agree with all the anti-this-and-that and I end up telling somebody to shut the Fu** up and thats not good for anybody including me.Im not a raging fu** this and Fu** that offline so I dont see any good in doing that online.LOL...I might drop in and post in some non political/religous stuff every now and then but thats about it.I've only posted one time in 3 weeks in the cave and that was in getuhgrips thread.Thats some sad shit.
Above ground I can even post to hixmix without getting into a pissing match.
Thanks for the help guys!
Thanks dudes!
I feel a little better now even though Hix thinks it might fry something.
Jeff,
I'll stick a multimeter on it and see what it reads.Im guessing it'll be a little over the 15 ohms that it says it is.
jake-owa,
I was thinking that it wouldnt harm it(I was hoping),but I wanted to make sure before I put very much more playing time into it.If pipeline said it would be ok for you to put a 6 ohm speaker in place of a 8 ohm then I'll trust his judgement.I should be ok with this speaker.
P.S.The cave is too hectic for me man.I dont agree with all the anti-this-and-that and I end up telling somebody to shut the Fu** up and thats not good for anybody including me.Im not a raging fu** this and Fu** that offline so I dont see any good in doing that online.LOL...I might drop in and post in some non political/religous stuff every now and then but thats about it.I've only posted one time in 3 weeks in the cave and that was in getuhgrips thread.Thats some sad shit.
Above ground I can even post to hixmix without getting into a pissing match.
Thanks for the help guys!
Kramer
Well-known member
hixmix said:
You have a point there hixmix.Im gonna put a multimeter on it and see what it reads.Im guessing it's gonna be a little more than 15 ohms.I hope so!
Sonixx
New member
it's not going to make any difference. 15... 16... 17...
also, when you test it with a multimeter you're only testing the DC resistance of the coil. the impedance the amp sees varies with frequencey. it can be all the way from < 6 ohms to > 30, based on frequency. the 15 ohms is a nominal ohms. don't worry.
the bigger concern is the power rating. Greenbacks usually come in 25 watt ratings. make sure it's not less than the amps rated output. for a single speaker setup, twice the amps rated output is pretty safe if you drive the amp hard a lot for long periods.
also, when you test it with a multimeter you're only testing the DC resistance of the coil. the impedance the amp sees varies with frequencey. it can be all the way from < 6 ohms to > 30, based on frequency. the 15 ohms is a nominal ohms. don't worry.
the bigger concern is the power rating. Greenbacks usually come in 25 watt ratings. make sure it's not less than the amps rated output. for a single speaker setup, twice the amps rated output is pretty safe if you drive the amp hard a lot for long periods.
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dragonworks
Banned
I would have to assume that no matter what a speaker is rated, if you actually test it, it wont test what it is rated.
There are tolerances in electronics, all resistors have tolerances, some +-10 %, +-5 %, +- two %, I would think this would apply to speakers also.
There are tolerances in electronics, all resistors have tolerances, some +-10 %, +-5 %, +- two %, I would think this would apply to speakers also.
Kramer
Well-known member
Thanks for the info sonixx.The amp is a 30 watt tube amp and the speaker is a Celestion G 12-65.Thats 65 watts so I should be ok.Im an idiot when it comes to this technical stuff.I've always plugged in and let it rip.
Thanks for the good info!
p.s. Dragonworks,
I looked up the Celestion G 12-65 on the net and sure enough,it is a 15 ohm speaker.
Thanks for the good info!
p.s. Dragonworks,
I looked up the Celestion G 12-65 on the net and sure enough,it is a 15 ohm speaker.
D
DJL
Self Banned
Kramer said:
I bet it's safe, but ask the amp manufacture to make sure.
Doug H
I'll be there
How did you know that the speaker was bad? I ask because I'm suspicious of the speaker in my combo. I can't see any tears in it through the grill but I haven't removed it to check. I don't know what would ever make a celestion go bad, but I'm getting a flat buzzing white noise sound in dynamic spikes and am wondering how to check the speaker out.
Mark7
Well-known member
Re: Re: Guitar Amp Speaker Question
That's because you've never seen a Vox Defiant (U.K. version), which is specifically set up to drive a 15 ohm speaker cabinet.
dragonworks said:
That's because you've never seen a Vox Defiant (U.K. version), which is specifically set up to drive a 15 ohm speaker cabinet.
pchorman
New member
15 ohms is within 6.25% of the desired loading, well within the tolerance of most speakers and other resistive loads.
An ohmeter across its terminals only yields the DC value, called resistance, not its impedance at audio frequencies. But if the resistance is slightly greater than 15 ohms, so will be its impedance!
Don't worry about it. The mismatch is slight.
An ohmeter across its terminals only yields the DC value, called resistance, not its impedance at audio frequencies. But if the resistance is slightly greater than 15 ohms, so will be its impedance!
Don't worry about it. The mismatch is slight.