Amp wattage vs cab wattage

[kdj771]

I think i know the answer to this but here goes:

I have an f30 combo plugged into a 4x12 lonestar cab. The f30 only puts out 30 watts, but my cab is 320 watts. A 30 watt amp is gonna drive the cab as much as say a 100 watt head is it? My gut tells me no. Will i get more juice out out of my cab with a higher wattage amp?

Let the record state that i feel very stupid asking this as i know quite a bit about this technical stuff.

 

[Mordimer]

Generally, the amp power should be from ~1 to even 2.5 times more than speaker power, so if connect your cab to more powerful amplifier you'll get more juice But remember that too powerful amplifier may destroy the speakers.

There's one more thing - 320W doesn't mean, that the cabinet needs such power. This is the power of all 4 speakers, so every single speaker is only 80W. This is why a 100W head is accurate for 4x12 cab

 

[Spudmurphy]

When I started out the rule was 50 watt amp = at least half again =75 watts of speakers so invariably you ended up with a 100 wat speaker cab. You need to drive the speakers move the air - get the "flame" of the speaker to project. - remember in Chemistry class the teacher showing you the hotest part of the flame - well a speaker has one too.

 

[Jimmyb]

Well, in an ideal world, the 100W amp would be around 1/3 'louder' than the 30W amp.

Because you're running a 4x12, you have a greater conal area, meaning that you're shifting more air than you would be in a small combo. This has a greater effect on the perceived volume than the wattage of your amplifier.

Where are you thinking about playing?

 

[ScreaminFloyd]

Anything over 50W is a waste. Unless you plan on playing in a stadium!
Too much head room in a 100W and will take too much volume to break it up nicely. Sometimes I remove my Marshall JVM205H and power my vintage 4x10 cab with a Marshal 5W A class combo. Sweat, loud, musical. I use string attack and guitar volume to control the cleans and crunchy mids. Some players really get hung up on the 100W thing and are dissapointed because they cant find a tone. 30W is plenty!

 

[jakedawgwhite88]

yep all responses are right on the money .... my mesa boogie mark 3 (on half power) never goes above 2 in a club ... at the moment ...(I want an attenuator) and mesavox's dc3 30 watt boogie is about there too. We've played some stadium venues and the 30 watt mesa can handle it with ease.

 

[jmmp]

Anything over 50W is a waste. Unless you plan on playing in a stadium!
Too much head room in a 100W and will take too much volume to break it up nicely. Sometimes I remove my Marshall JVM205H and power my vintage 4x10 cab with a Marshal 5W A class combo. Sweat, loud, musical. I use string attack and guitar volume to control the cleans and crunchy mids. Some players really get hung up on the 100W thing and are dissapointed because they cant find a tone. 30W is plenty!

I respectfully disagree with this statement. Not everyone is looking to get power tube distortion. I use all preamp distortion, and use the power amp to do just that, make it all louder. Yes it is a little loud to get it to the tube sweet spot (on my amp at around 10:30 on the master volume) but that is completely doable, because when there is no micing and PA present (such as at band practice) then I still have to turn it up to get into the mix with the band. Live I just get it to that sweet spot, and it's the perfect volume. Also I need the features my amp offers to just function in my band, and I have yet to see any amp with the same a mount of features with anything less than 50 watts, and even that 50 is a stretch because that is on a half power switch.

But yes, For that dynamic, power tube distortion sound, 100 watts is overkill.

Also, to the OP, Volume wise, its the sensitivity of the speaker that determines volume. I don't remember all the math behind it, but A higher sensitivity rating means it will be a noticeable amount louder than the same speaker with a lower sensitivity. Wattage on a speaker just shows how much that one speaker can handle.

 

[kdj771]

thanks for the replys guys, all good and valid responses. as was mentioned, im not really keen on getting my power amp break up, its not that i dont want it to, its just that im not looking to that as a crucial part of my tone.

im not asking this for the purpose of determining the age old question of how the amp size should relate to venue size, i just want to know if a larger power amp is gonna help me get more out of my cab, which has been answered.

Thanks again everyone

 

[littlephil]

Having an amp that outputs significantly less than the cab is rated for isn't a problem at all.
Cabs are rated for power handling, meaning your cab can take up to 320 watts before you'll start to damage the speakers.