Will a 2 or 4X12 cab make my combo louder?

[GCDEF]

I had been thinking that the another thread about whether or not a 335 could do metal had the dumbest posts in it. You have proven me wrong.

 

 

This particular topic, along with underpowering PA speakers, seems to generate the most misinformation and confusion among all the topics discussed.

[Yarbicus]

This particular topic, along with underpowering PA speakers, seems to generate the most misinformation and confusion among all the topics discussed.

 

 

Misinformation and confusion I can understand (as it were). It is the raw stupidity of a particular poster that has won today's award.

[GCDEF]

Misinformation and confusion I can understand (as it were). It is the raw stupidity of a particular poster that has won today's award.

 

 

I agree. I almost posted a response to that one too.

[Bubbluz]

To me a tube amp under 50 watts minimum has absolutely zero usefulness.

 

[Yarbicus]

Look, there are two things you need to know to answer the OP's question:

1. Match the impedance of the head to the cab. Doesn't matter how many speaker the cab has or how many watts the head puts out.

2. More speakers of the same size will make it easier to compete with the drums in a band.

Done.

[LARRY L]

More speakers move more air, so they will be bit louder than a single. Not all speakers are that efficient, some take more power to get the same output. An alnico speaker may need more watts to get a nice warm tone and do the flatting out trick. I do not like under driving speakers especially that are designed to handle a lot of watts. I own a couple Fender DRRI's modded and when I got rid of the C12k's, 100 watt Jensen and got a weber then to a p12n type Magnivox (1956) I had a huge appreciation for a lower watt, less stiff cone for my 22 tube watts. The old maggies blew away the other two in tone and were about 6 db softer.

[tech21man]

LYSOL guy...epic. You should already facepalm yourself.

 

Anyway, as far as the original question goes, the OP said exactly that the amp is a hair shy than giving him what he wants volume wise on stage.

 

That means that loud drummer or not, he needs more volume...

 

Dividing the power to two speakers, is like having two 10 watt (for the 20 watt astroverb) amps playing on stage. Doesn't matter if the one speaker is here and the other on the other set, or they both are in the same cab. They would get as loud as the 10 watt rating. That would be a wonderfull idea if and only if the amp shone to that area of performance (pushed close to 10 watts RMS). Unfortunately in tube amps halfing the impedance (which can be achieved by adding a second speaker in parallel) does not increase the watts at all. They remain the same. In solid state amps it does.

 

 

 

What I would do is find out exactly what the efficiency is of the built-in speaker. Then choose one with +3 or +6 db more. If it is to replace the built-in it should be one close enough sonically and good on open back cabinets...Else make a headshell, and drive a 112 closed or open back with the new speaker.

 

 

 

 

So to get the most out of the astroverb you need to maximize its efficiency as a system.

20 watts on the soldano with this speaker, is like 40 watts with a speaker with 3db more in efficiency and 80 watts like in case of a +6db more efficient speaker.

 

 

There are two buts though in this theory.

 

 

First, a new speaker will colour the tone two ways.

 

a) It might be different as an "eq filter" at the end of the chain as it is. So you will get a different result.

 

b) It might alter the whole way the amp reacts. If you love your amp exactly for that you might want to consider that making it louder will also mean not pushing the power stage so much. As a result the relationship between you pushing hard, negative feedback etc will change. Simply, your amps will reach the same decibels using less watts. Also consider the damping factor that is the current that the speaker's magnet makes by moving. It reacts to the power amp of your amp. Using a different speaker will change that somewhat although it also is a result of the amps initial design and how much the designer allowed for this to happen.

 

 

Another thing I noticed at my last gig.

 

I used a 6L6 40 watt peavey triple XXX combo (97 db rating for the internal 16 ohm speaker) with a brunetti 16 ohm extension cab (closed back) equipped with a V30 (16 ohm 100 db rating).

 

I would expect the V30 to dominate the mix eventhough it was beneath the combo. It didn't. At least for what I've heard on stage the high level placed combo speaker was always more audible. I really believe that the sensitivity though true isn't exactly linear. I pushed the amp (unmiced gig) and the two speakers weren't worlds apart in loudness...

 

 

As a result I wasn't considerably louder than my old mesa boogie f-30 with two EL84s and a V30 on stage. But the circuit allowed me more clean headroom and another sound with 6L6s.

 

 

So if I were in your position, I would just borrow a super sensitive 112 for a gig and see what happens. Take the amp to a higher level would help and also placing it in the left side of the stage as you face the crowd. Drummers tend to bury everything on the right side, says a soundman friend! Plus the closer to the drummer whichever side you play the less the sound will spread for him or you to hear and the easier the drums will bury guitars etc.

 

If you don't like the results of all of the above, mic it and get it over with!!! Or buy, unfortunately another amp.

[LARRY L]

 

Wow, there's a lot of wrong information in this thread. tlbonehead has it right. The concept is really simple. Power comes from amplifiers. Speakers are passive devices. Unless they are more efficient, or unless your existing speaker(s) are nearing their maximum output, adding speakers doesn't more more air and it doesn't add volume. Air movement comes from the excursion of the speaker, its in and out motion. When you add another speaker, you add more surface area, but you divide the power from the amp among all the speakers, which reduces each speaker's excursion and therefore its output and the amount of air that is moved. The water analogy is a pretty good one. Assuming you have a pump that can move a certain amount of water in a certain amount of time, it really doesn't matter if you hook 1 or 10 hoses up to it, it still moves the same amount of water. The principle is the same with amps and speakers. Those of you who say it's louder, where does the extra energy required to move the extra air come from since you're not actually adding any energy to the circuit? (That's a rhetorical question by the way. Just something to ask yourselves).

 

 

The output volume is not linear to the power input. So you will get more volume driving more speakers with the same power.

[Belva]

What I would do is find out exactly what the efficiency is of the built-in speaker. Then choose one with +3 or +6 db more. If it is to replace the built-in it should be one close enough sonically and good on open back cabinets...Else make a headshell, and drive a 112 closed or open back with the new speaker.

 

I said that back on page one. And again on the last page.:poke:

[LARRY L]

 

says a soundman friend! Plus the closer to the drummer whichever side you play the less the sound will spread for him or you to hear and the easier the drums will bury guitars etc. If you don't like the results of all of the above, mic it and get it over with!!! Or buy, unfortunately another amp.

 

 

I play on the opposite side about 40 ft away for that reason.

[Flogger59]

I used a 6L6 40 watt peavey triple XXX combo (97 db rating for the internal 16 ohm speaker) with a brunetti 16 ohm extension cab (closed back) equipped with a V30 (16 ohm 100 db rating). I would expect the V30 to dominate the mix eventhough it was beneath the combo. It didn't. At least for what I've heard on stage the high level placed combo speaker was always more audible. I really believe that the sensitivity though true isn't exactly linear. I pushed the amp (unmiced gig) and the two speakers weren't worlds apart in loudness...

 

 

How close were you to the stack? If your ears are 6' off the floor, and the combo speaker (for argument's sake) is 3' off the floor, and you were standing within a foot or so of the amp, then the bottom cab would be twice the distance to your ear compared to the combo speaker. Inverse square says that the bottom speaker will be 6db lower to your ear.

[CrackerD]

Lysol was right about one thing though:

 

A 50watt amp is not 1/2 as loud as a 100watt amp. A ten watt amp is 1/2 as loud as a 100w, through the same cabinet.

 

So, a 50w is like 85% as loud as a 100w.

 

 

 

 

 

But yeah, I have driven a 4x12 with a 1/2 watt head. And, it was considerably louder than a 1x8 for example.

[tlbonehead]

How close were you to the stack? If your ears are 6' off the floor, and the combo speaker (for argument's sake) is 3' off the floor, and you were standing within a foot or so of the amp, then the bottom cab would be twice the distance to your ear compared to the combo speaker. Inverse square says that the bottom speaker will be 6db lower to your ear.

 

 

precisely. Even mores-so when you consider that you are mainly just hearing the lower frequencies of the bottom speaker(if this is the scenerio) because highs are far more directional. And low frequencies don't create the same sense of loudness.

[tlbonehead]

Lysol was right about one thing though: A 50watt amp is not 1/2 as loud as a 100watt amp. A ten watt amp is 1/2 as loud as a 100w, through the same cabinet. So, a 50w is like 85% as loud as a 100w. But yeah, I have driven a 4x12 with a 1/2 watt head. And, it was considerably louder than a 1x8 for example.

most 8"s aren't very efficient, especially below 150hz or so.

[LARRY L]

 

How close were you to the stack? If your ears are 6' off the floor, and the combo speaker (for argument's sake) is 3' off the floor, and you were standing within a foot or so of the amp, then the bottom cab would be twice the distance to your ear compared to the combo speaker. Inverse square says that the bottom speaker will be 6db lower to your ear.

 

 

To make things even more complicated, your ears is more sensitive to the high frequencies but they do not radiate evenly from the speaker they tunnel out from the center perhaps 20 degrees or so. So the speaker needs to be aimed at you to get the full sound.

 

I was also thinking to get more volume you can personally hear, you could cheat a little by turning down the lows a bit, even low powered amps can scream out the upper mids and highs.

[Flogger59]

When I gig with a 20w amp I'll set it out front by the PA.Not having to tunnel through my ass makes a huge difference, AND the singers bitch less. Don't make for a happy drummer, though.

[tlbonehead]

When I gig with a 20w amp I'll set it out front by the PA.Not having to tunnel through my ass makes a huge difference, AND the singers bitch less. Don't make for a happy drummer, though.

that must create a dreadful onstage and FOH mix.

[GCDEF]

But yeah, I have driven a 4x12 with a 1/2 watt head. And, it was considerably louder than a 1x8 for example.

 

 

The difference would have been due to differences in efficiency and frequency response, not the number of speakers.

[Flogger59]

that must create a dreadful onstage and FOH mix.

 

 

Not at all, for a place where only vocals go through the system in a small room. I might angle it to bounce off a side wall to help dispersion and avoid ice picks, but it works quite nicely. Open backed cabs push almost as much out the back as they do the front.

[LYSOL]

I have found 100 watt amp to have in usefulness over a 50 watt is headroom .

 

Exactly!

[Belva]

Tilt steering wheels are good for increased head room too!
Oh wait. This ain't HCAF. sorry, my bad.

[Flogger59]

Tilt steering wheels are good for increased head room too! Oh wait. This ain't HCAF. sorry, my bad.

A true gentleman would offer to sit in the passenger's seat.

[IamBurnout]

A true gentleman would offer to sit in the passenger's seat.

 

 

I'd be willing to steer from that side, but I'm not working the shifter too.

[LYSOL]

Subjective bunch of cunts aren't we?!?!?!

[groovmongrel]

20 watts are not enough to hang with an acoustic drum kit.