[pickslide]

If you have 2 amp heads, both the same model, but one is 30 watts and one is 100 watts, what is the difference? Is the 100 just a lot louder than the 30?

 

[nine]

Theoretically, yeah. It'll just have a lot more clean headroom, provided they didn't change anything else in the design. There might be other slight tonal changes due to the difference in power running through the amp, but to be honest, that's just a guess on my part.

 

[TimH]

If you have 2 amp heads, both the same model, but one is 30 watts and one is 100 watts, what is the difference? Is the 100 just a lot louder than the 30?

Here are some differences:

More Headroom - The 30 watt amps distorts in the power section faster than the 100 watt amp

Different Feel - Higher Headroom amps don't squish as much as their lower counterparts

Difference Frequency Response - Generally the more wattage an amp has the more bottom end it puts out

Difference Tubes - there is a good chance the 100 watt amp is using el34's or 6L6's where as the 20 watt amp is using el84's (not for sure but it's an educated guess)

More volume - yes but maybe not as much as you'd think.

 

[nine]

Damn, I should've been a scientist or engineer. TimH just totally backed up my guess with some pretty official sounding facts. :food-smiley-004:

 

[EL34POWER]

But surprisingly. The 100 watter will not be 3.5 times louder. It'l be 3.25 db's louder. you need to double the power to gain 3db's.
That's why a Vox AC30 is so damn loud.

 

[pickslide]

Great info..thanks!!!! I am looking at possibly purchasing a Roccaforte and they offer the same model in 30w and 100w. I will mostly use it for around the house and playing in a band with some friends. I know this is a performing amp, but I figure if I am going to get something great, no point in holding back.

Thanks

 

[nine]

Unless you guys play at punishingly loud volumes, or gigantic venues, I bet the 30 watter will do ya. Test them both out and make sure to crank them up in the store. The guys that work there love that! Haha.

You might end up liking the 30 watter better because you'll be able to get a nice crunch going at band levels, whereas the 100 watter will probably be way too loud before you get crunch.

 

[EL34POWER]

Great info..thanks!!!! I am looking at possibly purchasing a Roccaforte and they offer the same model in 30w and 100w. I will mostly use it for around the house and playing in a band with some friends. I know this is a performing amp, but I figure if I am going to get something great, no point in holding back.

Thanks

ooooooh Witch Rocca are you looking at? New or used? The new Jennelle is bugging meNone

 

[pickslide]

Im looking at the HG 30 Head. I would look at getting one used, but I have no idea were to find used Roccas.

 

[pickslide]

What about 18 watts? How does that compare to 30w?

 

[washburned]

Consider

Volume is affected by a lot of things: Speaker efficiency and area can be a big factor; more efficient speakers use more of the power to produce sound energy than heat energy, and the more area the more air gets moved. Listen to the difference in a small combo with the built in speakers and then plugged into a two or four speaker cabinet.

I once saw a famous metal band in the '70s and noticed that the guitarist was using three and a half Marshall stacks. there was also a small "box" on top of the half stack. During the intermission I asked the sound engineer what the small box was: he told me it was a Fender Deluxe reverb, it was mic'd for the FOH, a signal was taken out to the Marshall half stack for live stage sound and the three full stacks were empty cabs/heads with pilot lights! Bass player similarly had four Ampeg SVTs, only one was loaded.

 

[nine]

During the intermission I asked the sound engineer what the small box was: he told me it was a Fender Deluxe reverb, it was mic'd for the FOH, a signal was taken out to the Marshall half stack for live stage sound and the three full stacks were empty cabs/heads with pilot lights! Bass player similarly had four Ampeg SVTs, only one was loaded.

That's pretty common. You've gotta put something on that huge stage and if you don't have a Stonehenge set with midgets dancing around it, a bunch of dummy speaker cabs work just fine.

 

[Emohawk]

Keep in mind too that voicing has a lot to do with it. You hear a lot of people say a 100w Marshall will blow away a 100w Mesa Recto. That's probably true, but only due to perception. The Marshall is voiced more in the upper mids which the human ear is more sensitive to. The Mesa with it's lower mid "scooped" focus doesn't seem as loud, even though in reality it's pushing just as much power and probably even working harder because it's driving more bottom end (which requires more power to drive effectively than mids or highs).

Also, wattage is a very misleading term - even more so in terms of tube instrument amplifiers. For example, Orange rates their amps at "clean" power (much like a hi-fi audio amplifier would be). I've heard that the new Tiny Terror actually drives around 28 watts at full song.

And, on the perception issue, guitar amps are generally driving midrange frequencies for the most part. Again, these are the frequencies the humar ear is most sensitive to. That means the 30w you're hearing from a guitar amp seems a lot louder than you might hear from your home stereo driving the same power, because you're home stereo is driving a wider range of frequencies and it's more about peak power than continuous power.

Also, 30w is actually pretty damn loud. When you consider that speaker sensitivity is generally measured at 1 watt 1 meter from the speaker using a constant tone (usually 1khz), and most speakers run in the 95db range (some industrials coming in at well over 100db - JBL's tend to be hyper-efficient for example), and then you take into account that you're pretty much more than doubling the sheer volume with a 30w amp (in SPL terms - roughly 10x power is required to double SPL level, all things being equal), that's pretty freakin loud!

 

[thegame]

You might end up liking the 30 watter better because you'll be able to get a nice crunch going at band levels, whereas the 100 watter will probably be way too loud before you get crunch.

IMO Master Volume circuits have improved dramatically over the last 10 - 15 years. You won't need to crank it too much to get good sounds with a GOOD Master Volume design. Therefore a 100w amp is just as usefull. Tonally I prefer them as they have much more bottom and authority, but the high end has more harmonics to it as well with the higher wattage, all else being the same.