How hot should speakers get?

[rcole_sooner]

I am wondering, 'cuz the back of mine are warm enough to be uncomfortable to touch. I've never felt of the them in the past, but I was pokin' around tryin' to stop some rattles, and noticed they were warm (kinda actually hot).

[Drew224]

If you push them, I think that's normal. The coil will definitely get hot as the speakers break up.

[speakrsrfun]

We are talking guitar speaker right.....It shouldn't get that hot, if it gets too hot the enamel on the VC wire will start to melt and the coil will separate and short in the gap, that's if it gets too hot. Now I've had some get to nearly 90 degrees Celsius but the application wasn't set up and the drivers were definitely not high quality, and input power was substantially higher than the rated Max wattage. With that being said even at 90 degrees the back plate never reached "uncomfortable" touching temps... How are you using these? I usually define damage when I smell the lovely smell of enamel burning and reduce the volume if that happens...

[River]

I've never heard of speakers getting hot. I'm no guitar-amp expert, but in my pre-guitar days I used to run a PA micing everything and running loud. Never felt a hot speaker.

[rcole_sooner]

It is not a high-quality speaker. It is a Celestion Seventy 80, rated 80 watts at 8 ohms. I was pushing it with my Marshall 50 watt head at 6 pre-amp and 5 volume. I jammed pretty hard for a little over an hour, using OD and boost pedals.

[speakrsrfun]

I've been designing and building Home Audio gear for 25+yrs as a hobby and I've had some Subs run very hot but never ever to the point of the back plate being too hot to touch. And temps of the coil were taken with FLIR after several thousand watts run to them at very low frequencies.

[speakrsrfun]

Have you had your amp serviced lately? or played it with any other combo?

[rcole_sooner]

It is a used amp, that I just bought off ebay. I have only played it with my cabinet(s). The coils (back of the magnets) were not too hot to touch, but they were very warm.

[hipofutura]

I would be suspicious that you have an impedance mismatch between the speaker and the amp. You should test the speaker DCR. Perhaps the VC is pooching on you. Push the cone in gently (and evenly), then release. Is there any scraping noise?

High powered speakers can run extremely hot, but I wouldn't expect it with a guitar amp. It's common to see speakers with holes in the dust cap or the back of the magnet to allow cooling of the voice coil. Typical of JBL, Altec, and most modern woofs.

[HOT-BRIT]

I would take it in and have it checked out, the speakers should not get hot like that

[rcole_sooner]

Originally Posted by hipofutura

I would be suspicious that you have an impedance mismatch between the speaker and the amp. You should test the speaker DCR. Perhaps the VC is pooching on you. Push the cone in gently (and evenly), then release. Is there any scraping noise?

High powered speakers can run extremely hot, but I wouldn't expect it with a guitar amp. It's common to see speakers with holes in the dust cap or the back of the magnet to allow cooling of the voice coil. Typical of JBL, Altec, and most modern woofs.

Well the amp is set at 8 and the speaker is labeled 8, for what that is worth.

There was some buzzing I was trying to track down. I never considered a speakers voice coil making such a sound. Is pooching where the coil swells and rubs on some parts of the cone? I will try to manually move it and see if I hear anything.

Originally Posted by HOT-BRIT

I would take it in and have it checked out, the speakers should not get hot like that

The amp or the speaker? Prolly, both, eh. The speaker is a cheap sucker, so I won't worry about it, except I don't want it to blow and hurt the amp.


Thanks, guys, this may have been a problem with these speakers all along, and I just never noticed. I have another speaker on order, a G12t-75, that will hopefully produce some better results. In the end, one speaker may not be enough, for that Marshall head. I'll have to make me a 2x12 cab, or get an attenuator.

Maybe it is the amp, but I hope not. I hate takin' stuff to techs. That is why I've resorted to doing most of my own tech work, but I don't know beans about amps.

[aneas fool]

Originally Posted by hipofutura

I would be suspicious that you have an impedance mismatch between the speaker and the amp. You should test the speaker DCR. Perhaps the VC is pooching on you. Push the cone in gently (and evenly), then release. Is there any scraping noise?

High powered speakers can run extremely hot, but I wouldn't expect it with a guitar amp. It's common to see speakers with holes in the dust cap or the back of the magnet to allow cooling of the voice coil. Typical of JBL, Altec, and most modern woofs.

I used altec speakers when I was a DJ running them full out for 4 hours straight non stop...the never got hot in any way just slightly warm ...for a speaker to get hot to touch there would have to be a mismatch in power rating

[SteveGangi]

There is a slim chance there is a mismatch. That should be unlikely though. Your Marshall may be rated at 50 Watts, but that rating is stated at a clean sound level. You will see something like 50Watts @ 1% THD or something like that. This means you are not overderiving (crunch) and this is a "just cruising along" rating. When you start to kick it harder, you do pump out a bit more power. The general rule of thumb is, take the amp power rating and double it. Either get a speaker that is rated higher, or use two speakers. Two speakers will generally sound better also.

Now having said all that... No, your speaker should not get so hot it is uncomfortable to touch. As with all electronics, heat is the enemy.

[rcole_sooner]

Well, I tried the "hot" speaker tonight with my Peavey C30.

I put another switched jack in the C30, so it would disconnect the internal speaker. I also put a dummy plug in the original external speaker jack, to switch the amp to 8ohm mode.

I actually forgot the dummy plug, at first, and was running the 8ohm speaker at what should have been 16ohms. I noticed some buzzing and popping, very similar to the Marshall amp. I quickly realized my fubar, and shutdown the C30, and put the dummy plug in place.

The result was that the speaker was free of buzzes and pops.

After my short set, I checked, and the speaker was warm, but not hot to the touch. Albeit my short set of Black Crowes stuff tonight, was much tamer than last nights C# and drop C# set.

I think once I get the 16ohm speaker in place, things will match-up and work much better.