Is 15W enough?

[Lt. Bob]

Many guitar players seem to think that their ears are either behind their knees, in their asses, or in a completely different part of the room. They will play with their amps on the floor behind them, next to the drum kit, or on the other side of it, or pointing at the bass player. And wonder why they can't hear it.

hahahaha

That's so true. I've always played with my amp on a stand or a chair so I can hear exactly what it's doing.
If nothing else, the directionality of highs means that if your amp is on the floor, you'll tend to set it brighter than you really want it.

 

[boingoman]

Outlaws-

Whoa. Those guys are nuts.


Blue whales can generate the equivalent of around 200db SPL in water. At 0.5hz. That's some bass.

 

[Keiffer]

For reference, speakers are rated based on Sound Pressure Level (SPL). A typical good speaker cabinet will produce about 100db with 1W. This link is a reference to common sound levels.

with do respect... that's an absolutely meaningless measurement wrt to actual use in a band setting. enclosure design, damping and a ton of other factors come into play... and especially in a heavy rock genre.

 

[bubbagump]

I never looked at guitar amp ratings as a measure of loudness. It takes 10 time the power to double the volume. So the way I have always looked at it is how much clean head room do you want? Get a 200 watt head when you want to really have to push the amp to get the power section to distort and get a low wattage amp to distort the power section sooner. At the end of the day it is all about tone. If you are playing some place that doesn't have a PA and is big enough for you to need a bigger amp, don't play there as we usually call those places dives. A 15 watt Class A with a single 12 can get really loud and handle most small to medium sized venues.

Additionally, most bands play with way too much stage volume. There is a point where the FOH can't turn you down any more and can't turn the vocals up any more. Singers can't hear the monitors. Guitar players can't hear the bass or vocals.... Keep your stage levels reasonable and you might actually hear what your bands mates are playing AND allow the FOH to actually give you a good mix.

As for our blue whale friends, I thought the theoreitcal max of sound was around 190db? Or is that only in air adn with the higher density of water it can push past that?

with do respect... that's an absolutely meaningless measurement wrt to actual use in a band setting. enclosure design, damping and a ton of other factors come into play... and especially in a heavy rock genre.

Yup, those are usually measure at 1khz. It ignores the rest of the spectrum and part of what makes a guitar speaker sound as it does is its inability to reproduce all frequencies evenly as we would want in a PA speaker. That is why all those old Peaveys with Black Widows sound so awful for everything but pedal steel. They were too accurate for a guitar speaker. OF course this ignores cabinet design. With no cabinet, your speaker is worthless, so i sure hope you measure 1w/1m with it in a cab.

EDIT: As he says below, it will tell you what to expect, but it is not the end all due to the fluctuation across the spectrum that is common in guitar speakers.

 

[Ed Dixon]

with do respect... that's an absolutely meaningless measurement wrt to actual use in a band setting. enclosure design, damping and a ton of other factors come into play.

Wrong again. Most SPL rating for what I describe are for cabinets. Go to any speaker firm like JBL and check out their cabinets. That's the way they are rated, and the figures are very useful in determineing what to expect.

Most users buy cabinets, not raw speakers, and that the way they are rated.

Ed

 

[boingoman]

with do respect... that's an absolutely meaningless measurement wrt to actual use in a band setting. enclosure design, damping and a ton of other factors come into play.

It isn't meaningless if you can double your volume just by using a more sensitive speaker. Tone comes first (IMO) but if I can find a louder speaker that I like, that's huge. More volume, same power.

 

[Ed Dixon]

EDIT: As he says below, it will tell you what to expect, but it is not the end all due to the fluctuation across the spectrum that is common in guitar speakers.

Very true. Speaker cabinet efficienty rating (SPL) give you an indication of efficiency as compared to other cabinets also being considered. The bottom line is how it sounds to the buyer.

The real point is that cabinet efficiency can make a world of difference in resulting volume. A 100W amp may produce considerably less volume than a 25W amp with more efficient speakers.

When I buy speakers I look at three things (beyond price and sound). One is weight, the second is effiiciency, and the third size. If I can't carry it or it's won't fit in the car, it won't do me much good.

Ed

 

[ggunn]

I totally agree about the soundman part ....... in local club type situations I, personally, prefer to get al my sound from the stage 'cause I don't like a soundman having control of how my git sounds. First, I don't see that many good soundmen ..... 2nd, the only person that really knows what I want is me.

In the first place, there's no way you can tell from the stage what the mix is out front. In the second place, the PA doesn't change your guitar tone, so the sound man doesn't change how your "git sounds". I would much rather get a good tone from my amp at a comfortable volume, where I can hear everything that is happening on stage, and let the FOH guy worry about the mix. If I'm playing for the room, I have to play so loud that all I can hear is me. YMMV of course, but IMO that is a silly 'tude.

 

[boingoman]

As for our blue whale friends, I thought the theoreitcal max of sound was around 190db? Or is that only in air adn with the higher density of water it can push past that?

Yeah, that's an equivalent SPL in air. The denser the material, the higher possible spl.

Max SPL is determined by the limits of the medium. In 1 atmosphere of pressure (earth's surface), 0 atmospheres (vacuum) and 2 atmospheres form the limits of possible clean SPL. Supposed to be around 195db or so. After that, the sound starts to clip. Like a rocket launch or bomb explosion. At that point they call it an overpressure. A Saturn rocket used to put out something like 50 million watts of acoustic power.

Some stuff I've seen says air starts to get non-linear around 150db- shit starts to sound wrong and all kinds of odd frequencies develop.

On a planet with high ambient pressure, like say 10 atmospheres, the possible SPLs in air ar larger, because the pressure is farther above zero to start with. Same for water.

 

[ggunn]

I offer no position on one amp over another for any particular user. Each has to make up their own mind up as to what works for them. However my comments on the physics of sound are fact, not opinion. For the record, I've been playing for 42 years and I have three degrees including one in EE.

My, aren't we an educated bunch? I have a BSEE and a BSCHEM, myself. I've been playing for 43 years, neener neener.

I've seen all the equations and worked all the math, but I have a 15 watt Blues Jr and a 50 watt Marshall. If I crank the Jr all the way up I can stand a few feet from it and play. If I crank the Marshall, I cannot stand to be in the same room with it. Maybe that is just a couple of dB more, but I can tell you that it is a couple of dB that make a HUGE difference.

 

[boingoman]

When I buy speakers I look at three things (beyond price and sound). One is weight, the second is effiiciency, and the third size. If I can't carry it or it's won't fit in the car, it won't do me much good.

Ed

At some point common sense and reality take over. Lugging a half stack up three flights of stairs to play for 30 minutes on a five-band hardcore bill eventually breaks through to the most determined volume hound. Usually during a 3 a.m. load-out sometime after the age of 30.

 

[notCardio]

Some years ago I got involved in a yearly town festival that involved a “loudest car stereo” contest. The first year I just showed up to judge. The day after the contest I purchased a sound pressure meter.

In following years, being somewhat wiser to what to expect, I arrived with sound meter and ear blocking head phones. The last year the winner was a guy with a Chevy Vega with a number of 18” speakers mounted where the rear seat used to have been. When music played, and the doors were closed, the sheet metal on the car moved in and out.

Ed

Jeez, I wouldn't have thought there'd be any sheet metal left on a Chevy Vega in existence! They should all be little rust colored piles of dust by now, with an aluminum block sitting in the front of the pile.

 

[Lt. Bob]

In the first place, there's no way you can tell from the stage what the mix is out front. In the second place, the PA doesn't change your guitar tone, so the sound man doesn't change how your "git sounds". I would much rather get a good tone from my amp at a comfortable volume, where I can hear everything that is happening on stage, and let the FOH guy worry about the mix. If I'm playing for the room, I have to play so loud that all I can hear is me. YMMV of course, but IMO that is a silly 'tude.

Bullshit ..... first off, I've been playing pro for 42 years 5 to 7 gigs a week every single week year after year. I can tell exactly what the mix is out front from stage after all those years of mixing sound from the stage. If you can't that's fine ..... but I can.
Secondly ..... for the vast majority of clubs , a comfortable volume on stage is also enough volume for the room ..... sometimes you might put a little small amount in the PA to 'spread ' the sound but most rooms my stage sound is enough. Third, I use a Mesa Blue Angel and usually have it set at the 18 watt setting which is nowhere near loud enough even wide open (which I never use but still) so that I can't hear the drums and bass.
Fourth ...... PA can and do change the tone of your git if the sound,man changes it. Let's say he doesn't like a bright git but you do, (I don't but just for the sake of an example) so he rolls of the highs ...... there's your tone change right there.

Now, as you said, YMMV and I have plenty of respect to each and every different style and way of playing. For example, for me ... something like the POD XT Live doesn't sound good in my hands .... but I've heard it sound good for other people. What works for you is fine so don';t characterize my attitude as 'silly' when I probably have way more experience and make way more money at this than very many people you know.
And note: I'm not saying your way is wrong ..... I was just saying what my personal preferences are that I've arrived at for me based on years and years of playing every single night.

 

[Ed Dixon]

Bullshit ..... first off, I've been playing pro for 42 years 5 to 7 gigs a week every single week year after year. I can tell exactly what the mix is out front from stage after all those years of mixing sound from the stage. If you can't that's fine ..... but I can.

You may be able to guess well, but that's what it is. Few can do this, but it sounds like you can. For small clubs this stands a greater chance of success. However it fails in many live cases. Playing a large room, no one on stage can tell how it sounds at the other end a gym distance away. Only the sound person can. You can guess, and perhaps guess well, but they can hear.

In small clubs, PA use is very different than in large rooms. Stage volume may play a big part in instruement sound for the audience. The PA may contain mostly vocals. However play a room with 2500 people, and stage volume is useless. Only what comes through the PA is what they're going to hear.

Ed

 

[ggunn]

Bullshit ..... first off, I've been playing pro for 42 years 5 to 7 gigs a week every single week year after year. I can tell exactly what the mix is out front from stage after all those years of mixing sound from the stage. If you can't that's fine ..... but I can.
Secondly ..... for the vast majority of clubs , a comfortable volume on stage is also enough volume for the room ..... sometimes you might put a little small amount in the PA to 'spread ' the sound but most rooms my stage sound is enough. Third, I use a Mesa Blue Angel and usually have it set at the 18 watt setting which is nowhere near loud enough even wide open (which I never use but still) so that I can't hear the drums and bass.
Fourth ...... PA can and do change the tone of your git if the sound,man changes it. Let's say he doesn't like a bright git but you do, (I don't but just for the sake of an example) so he rolls of the highs ...... there's your tone change right there.

Now, as you said, YMMV and I have plenty of respect to each and every different style and way of playing. For example, for me ... something like the POD XT Live doesn't sound good in my hands .... but I've heard it sound good for other people. What works for you is fine so don';t characterize my attitude as 'silly' when I probably have way more experience and make way more money at this than very many people you know.
And note: I'm not saying your way is wrong ..... I was just saying what my personal preferences are that I've arrived at for me based on years and years of playing every single night.

Sorry if I offended you, but I assure you I am no neophyte at this stuff, either. IMO, if a sound man needs to roll off some of your high end to make room for the vocals, then that's what needs to happen irrespective of what you'd like. As for the rest of it, well, if we disagree, then we disagree.

Peace.

 

[Keiffer]

it really boils down to this... is 15W, 18W, 20W, ... enough to cover Metal or very Hard Core often in very different venues Big, Small, Inside, Outside.

the answer is NO. I would never depend on an amp that low in wattage as my main giggin amp. if it's a secondary amp, then that's another matter.

with the larger wattage amp, one can always turn the amp down, turn it around, put a blanket halfway over the cab, load half the cab and so on... but if you don't have enough power and you need it, you're sunk.

get at least 50W with the option of loading two or four speakers. it'll work for virtually every place you want to play, be it inside or outside.

 

[notCardio]

And Ed, I'll bet those 18's were Cerwins, right? Get it?

Sorry. I'm just amusing myself today.

(insert audio clip here of 'Let's Make a Deal' horns going Wah-wah-wah-waaaaa.)

 

[GONZO-X]

i've been on both sides of the gigging situation....
times when the stage, club and audience required something along the lines of a 100 watt half stack..
and other places where 5 watts would have been plenty!!
LOL

here's what i did, for whatever it's worth..

i got a 60 watt mesa boogie mark2b head.

i downsized my 4x12 into (2) 1x12 closed back cabs, easy to carry, light weight, but easy to spread out, stack, tilt one backwards, any way you can imagine to either get the volume off the stage, or on it.....

this was enough power for about any venue, but with the master volume, i could easily turn down for the few gigs where it had to be really quiet.
i added a hotplate somewhere along the line, to crank the amp and still get good overdrive from the output section, when i need/wanted.

if you have an effects processor, that has 'stereo' ouputs, here's another trick you can do....

if you decide on a 15 watt amp (plenty loud enough for typical small-medium clubs), you can take a feed out of the effects loop or slave out (most decent amps have this option) and feed it to the effects unit... split the signal coming out of that, and send one back to the amp the other off to a second amp and speaker (could be a combo, could be a rackmount deal, a tube power amp into another identical speaker(s) would be ideal) and then you can dial THAT amp in to double the strength of your onstage sound, as well as give the sound man two signals to work with (you could get real creative with this, use a mixer, 3 cabinets, a stereo power amp ala EVH- split the signal 3 ways- dry center cab, wet left and right cabs in stereo) with the center being the raw amp signal unaffected...soundman can blend the effects into the raw sound at will.

in other words, if you got a 15 watter, later decided it wasn't beefy enough, there are ways to add on, or piggyback..

there's just nothing worse than having a 100 watt rig, sitting on 0.5 (idle)

tube amps like to work, and sound best when pushed close to the limit.

headroom and your tone, decides on the watts ultimately.
you can't get SRV tones with a 15 watt amp, at stage volume.
you need extra watts for all that clean headroom........

 

[GONZO-X]

i've seen 15 watt THD univalves used this way.....

pushing the center cab, then the slave out to a stereo processor and onto a stereo power amp driving 2 more cabs, left and right.


that REALLY sounded cool.

 

[Ed Dixon]

And Ed, I'll bet those 18's were Cerwins, right? Get it?

Sorry. I'm just amusing myself today.

(insert audio clip here of 'Let's Make a Deal' horns going Wah-wah-wah-waaaaa.)

They might have been, but I'd have to 'Contact' those from the past and see if they could 'Foster" an answer to this alien sounding question...

Ed