Dumb question about cab wattage handling

[GAWA]

I need help with this. I'm looking at getting a Spider II head. It's 150 watts and I'm wondering what cab I can use with it. I was reading online that the Line 6 Spider II mkII 4x12 cab can handle 150 watts but I'm not sure if it would be able to be used with the head. Even though it says it can handle 150W I'm just worried that the 150W head would be too much for it? Would I need to get the Line 6 4x12 that can handle 300W? But its so much more expensive!

I know its a stupid question but I just want to be sure about this before I make a purchase. Cheers

[RW James]

Re: Dumb question about cab wattage handling

I would think a 150 watt cab would be just about right for a 150 watt head. Am I missing something here?

[GAWA]

Re: Dumb question about cab wattage handling

I would think a 150 watt cab would be just about right for a 150 watt head. Am I missing something here?

lol I know. I just thought that maybe 150watt handling meant that the cab could take UP TO 150 watts, and that a 150 watt head might be too much for it? Because when I was reading online it said the cab was suitable for the 75watt Spider II head.

I know it's a stupid question but it confused me and I want to make sure about it before I spend my money

[anewdefguitarist]

Re: Dumb question about cab wattage handling

dont worry, i've wondered that myself. i have marshall 2x12 that says it can handle 150 watts, and i asked one guy at a guitar store about a 120 watt head, and he said right away, "no no, it'd blow your cab." ...i don't understand why it would but apparenlty he thinks it will...i dont understand why it would though....???

[ShredFetus]

Re: Dumb question about cab wattage handling

The Watts that a solid state amp is rated for aren't consistant... a 150watt head might output 150 watts most of the time... but is capable of a higher peak output spike... I'm not sure how much but maybe up to around 180watts. I always though it was good practice to have a cab that was capable of twice the watts of the head.

Hopefuly some of the other guys will chime in & add a bit more detail for you.

*EDIT* ignore all this, I have no idea what I'm on about!

[SlyFoxx]

Re: Dumb question about cab wattage handling

150 watts into a 4x12 will produce enough volume to make your pants flap. Don't worry. You're good. ShredFetus has it wrong here. Short peaks over your cabs rating are of no worry. (99% of the time) It's average watts that tend to cook the goose....ummm errr speakers.

[ShredFetus]

Re: Dumb question about cab wattage handling

cool thanks for clearing that up

[krankguitarist]

Re: Dumb question about cab wattage handling

With a solid state amp you should be fine. I read somewhere that It's best to have a cab pretty evenly matched, or even rated under your amp's wattage rating, when using a solid state amp. Somthing about how the speakers will start to break up before you start overdriving your amp, so ya turn down till your speakers aren't being overdriven anymore. Which, then, prevents you from overdriving the power section of your amp, and overdriving the power section on a SS amp can cause square waves that wreak havoc on your speakers, blah blah blah blah blah blah blah *insert technical mumbo-jumbo here*. That could be pretty apocryphal though. Don't take my word for it.

If it was a tube amp, that'd be a different matter. Back when I was runnin my old JCM800 100w head through a marshall 2X12 rated for 150 watts, I'd start overdriving the speakers around 5 on the master volume.

[RW James]

Re: Dumb question about cab wattage handling

Someone (with doubtful veracity) once told me that if you have a speaker rated too much higher than the amp, the amp has a harder time driving the speakers and you actually lose volume. He went on to say that if you have speakers rated slightly below the amps rating you can actually get more volume at a lower setting.

Like I said, I'm not sure he knows what he is talking about all the time - but it kind of makes sense.

[devastone]

Re: Dumb question about cab wattage handling

You'll be fine with the Spider head and the 150W cabinet.

Someone (with doubtful veracity) once told me that if you have a speaker rated too much higher than the amp, the amp has a harder time driving the speakers and you actually lose volume. He went on to say that if you have speakers rated slightly below the amps rating you can actually get more volume at a lower setting.

Like I said, I'm not sure he knows what he is talking about all the time - but it kind of makes sense.

Sorry Rick, but he doesn't. It's the load (impedance) that makes the amp "work". As far as volume, or power out vs power in to the speaker, that's the efficiency or "sensitivity" as listed on most speaker spec sheets. For example the Eminence Wizard's sensitivity is listed at 103dB while a Celestion G12T-75's sensitivity is listed as 97dB. This measurement is listed on Eminence spec sheets as: "The average output across the usable frequency range when applying 1W/1M into the nominal impedance." Meaning they put 1W of power into the speaker, sweeping through the speaker's frequency range, and average the output of the speaker across that range as measured by a sound meter placed a 1 meter from the speaker.

[RW James]

Re: Dumb question about cab wattage handling

Sorry Rick, but he doesn't. It's the load (impedance) that makes the amp "work"...

I knew that... I really did... just kind of forgot it for a minute. Thanks for affirming that this guy is an idiot. He owns a local music store and I shutter to think about the crap he is telling people around here.

[GAWA]

Re: Dumb question about cab wattage handling

You'll be fine with the Spider head and the 150W cabinet.

Cheers dude just wanted that confirmed. Thanks everyone!