Head Wattage >>> Can Speakers Take It?

[danswon]

I have a 2x10 cab with some rare early 80s celestions (which, incidentally, used to belong to Mick Ronson) and I'm thinking of trying 150 watt head through it. Is this a bad idea? I'm guessing the cab should probably have more like 50 watts running into it. I really don't know anything about this stuff. Would it be ok if i just didn't turn it up REALLY REALLY loud?

[Brewski]

what are the speakers rated to handle? it's written on the back of the speakers - multiply it by two and that the MAX wattage you should throw at your cabinet - otherwise bad things might happen.

[danswon]

I will check. But I'm wondering if, in this case, the wattage just means volume - in which case it would be fine if i just play at a reasonable volume. Or does it mean the current going to the speakers? I was terrible at physics in school

[Belva]

Brewski is on the right track. If your head is 150 watts continuous and your speakers each say 150 watts, you're good. Because this will give you 300 watts max which is about what the speakers would handle (150 watts max X2 = 300 watts). I'd bet these speakers are rated at 50 watts max for a total of 100 wats max. If the head is 150 watts max you're pushing the envelope. Frinstance, say you have a 50 watt continuous (rms) head and you have a speaker rated at, say 35 watts max, even at very low volume the speaker isn't long for this world.

[DaleH]

Keep the volume down and as long as the ohms match you should be fine.

[guitarman3001]

 

Brewski is on the right track. If your head is 150 watts continuous and your speakers each say 150 watts, you're good. Because this will give you 300 watts max which is about what the speakers would handle (150 watts max X2 = 300 watts). I'd bet these speakers are rated at 50 watts max for a total of 100 wats max. If the head is 150 watts max you're pushing the envelope. Frinstance, say you have a 50 watt continuous (rms) head and you have a speaker rated at, say 35 watts max, even at very low volume the speaker isn't long for this world.

 

 

 

I don't believe this is the case. RMS is basically the amp's maximum sustained output, not what it puts out at every volume. If you have a 100 watt head but run it at low volumes, you can run it into a lower wattage speaker with no problems. You'll start having problems when you start pushing the amp, then you'll be driving the speakers with more wattage than they are rated for.

[ashasha]

Keep the volume down and as long as the ohms match you should be fine.

Yep. Unless you're close to diming the thing you aren't pushing anywhere near that 150W. And most times (not everytime) you can tell when the speakers on the threshold of stupidity and just coming apart.

 

Apply common sense liberally. If you pull a Back to the Future move you may be impaled by voice coils. If you raise the volume slowly until it sounds right you're probably more than fine.

[danswon]

ok thanks guys i think it's good to push speakers but like you say, not past the point of stupidity. unfortunately I am very frequently way past the point of stupidity. what are voice coils?

[mrbrown49]

Also keep in mind that 150 watts isn't the max output of the amp. It's the output before power section breakup, so you need to keep your volume well below that point. For example a "50 watt amp" may have a max output of 75 watts but that will vary depending on the amp design. Typically you add 50% when picking speakers for an amp to keep things in check. A 50 watt amp will generally be paired with speakers rated at 75 watts or more.

[DaleH]

 

ok thanks guys i think it's good to push speakers but like you say, not past the point of stupidity. unfortunately I am very frequently way past the point of stupidity. what are voice coils?

 

 

http://www.guitarsite.com/news/features/guitar_speaker_power_handling/

[Wyatt]

There is some bad advice in here.

 

First of all, it would help to know the amp.

 

Second it would help to know the speaker.

 

Vintage Celestions were rated for PEAK wattage. Original Greenbacks would blow if feed more than 25 watts, that's why Marshall paired their 50-watt heads with 4x12 cabinets (and 100-watt head with TWO 4x12 cabs) back in the day. A 50-watt Marshall JMP will usually start to exceed 50 watts shortly after 3 on the Volume knob...not 9 or 7 or 5...but 3 (marhsall was a little conservative on their output measurements

 

So, it's naive to assume you can, by ear or by math, keep an amp dialed down to the safe level. If the amp is a 150-watt tube head, it may well exceed 50 watts by 1 or 2 on the Volume dial depending on how the amp is designed and the taper of the volume pot.

 

If the cab is 50 watts, it would be sheer stupidity to hook it to a 150-watt head at all.

 

Note, it is a 150 watt output rating and not a 150 watt consumption rating, correct?

[danswon]

Well I'm looking at buying the new Fender Mustang V which is 150 watts. I haven't got the speaker cab right now to check, all I can remember is it has 2 obscure early 80s 10" celestions (I've tried to find info on them previously with no luck, even Celestion couldn't help me out)

[danswon]

I just saw this http://www.peavey.com/products/instamplifiers/guitaramps/vypyr/index.cfm/item/117520/Vypyr®%2030.html

Could be the answer to my problem

Anyone used one?

[ashasha]

There is some bad advice in here. First of all, it would help to know the amp. Second it would help to know the speaker. Vintage Celestions were rated for PEAK wattage. Original Greenbacks would blow if feed more than 25 watts, that's why Marshall paired their 50-watt heads with 4x12 cabinets (and 100-watt head with TWO 4x12 cabs) back in the day. A 50-watt Marshall JMP will usually start to exceed 50 watts shortly after 3 on the Volume knob...not 9 or 7 or 5...but 3 (marhsall was a little conservative on their output measurements So, it's naive to assume you can, by ear or by math, keep an amp dialed down to the safe level. If the amp is a 150-watt tube head, it may well exceed 50 watts by 1 or 2 on the Volume dial depending on how the amp is designed and the taper of the volume pot. If the cab is 50 watts, it would be sheer stupidity to hook it to a 150-watt head at all. Note, it is a 150 watt output rating and not a 150 watt consumption rating, correct?

One thing that I know on this place (and this is purely my opinion) is that if Wyatt says it's so than it's so. That's not my typical sarcastic, tongue in cheek dig, I take what he says as gospel so my deepest apologies for providing what could have been disastrous information.

 

You didn't do it yet did you?

[GCDEF]

 

Frinstance, say you have a 50 watt continuous (rms) head and you have a speaker rated at, say 35 watts max, even at very low volume the speaker isn't long for this world.

 

 

That's just not correct. At very low volumes the amp would be putting out way less than its maximum 50 watts. "Continuous" doesn't mean that it continuously puts out 50 watts, it means that's the maximum output it can sustain if you turn it all the way up.

 

To the OP, you should be okay at bedroom or low performance volumes, and you should hear the speakers breaking up before they blow, in which case you should turn it down. But without knowing more about what you have, it's impossible to say for sure.

[GilmourD]

 

There is some bad advice in here. First of all, it would help to know the amp. Second it would help to know the speaker. Vintage Celestions were rated for PEAK wattage. Original Greenbacks would blow if feed more than 25 watts, that's why Marshall paired their 50-watt heads with 4x12 cabinets (and 100-watt head with TWO 4x12 cabs) back in the day. A 50-watt Marshall JMP will usually start to exceed 50 watts shortly after 3 on the Volume knob...not 9 or 7 or 5...but 3 (marhsall was a little conservative on their output measurements So, it's naive to assume you can, by ear or by math, keep an amp dialed down to the safe level. If the amp is a 150-watt tube head, it may well exceed 50 watts by 1 or 2 on the Volume dial depending on how the amp is designed and the taper of the volume pot. If the cab is 50 watts, it would be sheer stupidity to hook it to a 150-watt head at all. Note, it is a 150 watt output rating and not a 150 watt consumption rating, correct?

 

 

I was going to say this but Wyatt beat me to it.

 

Beyond that, what if your dog/cat/kid/clumsy wife/evil brother happened to saunter over and knock the volume up and you didn't realize it. BOOM! Dead speakers.

[cratz2]

Basically what Wyatt said is what I would recommend.

 

What DaleH said is what I'd personally do, but I don't tend to crank 150W amps all the way up.

 

It would definitely help to know the exact amp we're talking about. It might be significantly over-rated at 150W.

[GCDEF]

Basically what Wyatt said is what I would recommend. What DaleH said is what I'd personally do, but I don't tend to crank 150W amps all the way up. It would definitely help to know the exact amp we're talking about. It might be significantly over-rated at 150W.

 

He already said the head he's talking about.

http://www.fender.com/products/mustang/models.php?prodNo=230005

[curseoftruth]

So why does Orange sell their cabs (2x12 and 4x12) year after year for their 30 to 120 watt heads with V30s? Sounds like a lot of bull{censored} science in this thread. I've run my 100 watt head with Celeston Vintage 30s for years at massive volume for hours on end and it sounds amazing. The other guitarist in my band has a cool old Marshall cab with V30s (from the 80s, so not that old) that gets routinely thrashed with 100 to 120 watt non master volume heads and they sound amazing and loud. By all of your logic here, we should have blown the speakers years ago.

[JoeBoy]

Contact these guys if you want to be sure. Also check out the FAQs. They are very helpful even if you don't buy from them.

http://www.avatarspeakers.com/

[GilmourD]

 

So why does Orange sell their cabs (2x12 and 4x12) year after year for their 30 to 120 watt heads with V30s? Sounds like a lot of bull{censored} science in this thread. I've run my 100 watt head with Celeston Vintage 30s for years at massive volume for hours on end and it sounds amazing. The other guitarist in my band has a cool old Marshall cab with V30s (from the 80s, so not that old) that gets routinely thrashed with 100 to 120 watt non master volume heads and they sound amazing and loud. By all of your logic here, we should have blown the speakers years ago.

 

 

The Vintage 30 actually has a power rating of 60W, so a 2x12 could handle 120 watts and a 4x12 could take 240.

 

http://professional.celestion.com/guitar/products/classic/spec.asp?ID=4

[cratz2]

So why does Orange sell their cabs (2x12 and 4x12) year after year for their 30 to 120 watt heads with V30s? Sounds like a lot of bull{censored} science in this thread. I've run my 100 watt head with Celeston Vintage 30s for years at massive volume for hours on end and it sounds amazing. The other guitarist in my band has a cool old Marshall cab with V30s (from the 80s, so not that old) that gets routinely thrashed with 100 to 120 watt non master volume heads and they sound amazing and loud. By all of your logic here, we should have blown the speakers years ago.

 

I don't think I quite follow your logic... An Orange 4x12 with Vintage 30s would be rated to handle 240 watts max. Running a 100 to 120 watt head into it would be a textbook example of what Wyatt suggested.

 

Same thing with running a 50W Marshall into a 4x12 loaded with 4 25W Greenbacks.

 

 

And even a 2x12 with Vintage 30s is still rated at 120 watts... Running a 100w or 120w amp into a 2x12 with Vintage 30s would probably last quite a while.

[Belva]

 

That's just not correct. At very low volumes the amp would be putting out way less than its maximum 50 watts. "Continuous" doesn't mean that it continuously puts out 50 watts, it means that's the maximum output it can sustain if you turn it all the way up. To the OP, you should be okay at bedroom or low performance volumes, and you should hear the speakers breaking up before they blow, in which case you should turn it down. But without knowing more about what you have, it's impossible to say for sure.

 

RMS = root/mean/squared or continuous output. At least that's what they taught me when I went to school. No you wouldn't blow 35w speakers with a 50w rms head right away. But the first time you get carried away and crank it (none of us here do dat!) Buh bye speaker.

The rule of thumb stated to have a 50% cushion is good advice.

Something else to keep in mind is the fact that you just can't trust amp makers when it comes to power output. None of us mortals have the ability to check what they're saying is true. Kinda like the horsepower wars with cars. That's why speaker makers recommend the 50% cushion.

[GCDEF]

 

RMS = root/mean/squared or continuous output. At least that's what they taught me when I went to school. No you wouldn't blow 35w speakers with a 50w rms head right away. But the first time you get carried away and crank it (none of us here do dat!) Buh bye speaker. The rule of thumb stated to have a 50% cushion is good advice. Something else to keep in mind is the fact that you just can't trust amp makers when it comes to power output. None of us mortals have the ability to check what they're saying is true. Kinda like the horsepower wars with cars. That's why speaker makers recommend the 50% cushion.

 

 

You said "even at very low volume the speaker isn't long for this world.", and that is inaccurate.

[Belva]

 

You said "even at very low volume the speaker isn't long for this world.", and that is inaccurate.

 

Lack of clarification on my part:facepalm:. Usually, a 50W max speaker will handle about half of that continuously, or 25W. Go feeding that a steady diet of 35W and it won't be long before it cries uncle. Turn it up a little and watch it go up in smoke.

So getting back to the OP's question. Chances are these are greenbacks rated at 25W max each. Total is 50W. I wouldn't even try running a 150W head into these.

This is rock & roll. Y'ever know someone with an electric guitar who can resist crankin' it? Me niether.