Louder speakers

Fatfingers

I've just built an Ampmaker P1800 and although I'm delighted with the noise it makes, I'm a little disappointed that it's not louder. I built an SE5 a few years ago and love the noise that makes too, but having tried it at a rehearsal it just wasn't quite loud enough to keep up with a band. I was really hoping the P1800 would be, but it's barely any louder. I've played both through a Celestion Greenback. The cab I'm planning on fitting the P1800 into is this old Selmer (once the speaker of a Selmer Lead 30). It has two old cheap Celestions in it (not sure what but nothing exotic, even by Celestion's standards). 

My question is, what 12in speakers can I use that will give me a noticeable volume gain. In other words, which guitar speakers are really efficient?

ThorpyFX

The Db rating has a massive effect on the volume a speaker outputs. For instance i had a 100dB efficiency speaker in my Plexi 7, it was just too damned loud for home use. so i chose a 10" greenback which is 95dB efficient, its now roughly half as loud (and sounds epic but thats by the by). The dB scale is logarithmic, approximately a 3dB increase in volume doubles the output your ears receive.

In short, look at the dB rating of the speakers in there, raise it up to 100dB or more (if they are lower) and watch the output rise.

ICBM

Fatfingers said:

My question is, what 12in speakers can I use that will give me a noticeable volume gain. In other words, which guitar speakers are really efficient?

Celestion Alnico Blue, Alnico Gold, or V30.

Slightly less so - G12H-30. It's also rated at 100dB, but doesn't sound quite as loud because it has a cleaner and less middy tone. Greenbacks aren't much quieter either despite the slightly lower rating, because they're also middy and slightly dirty-sounding.

Take other manufacturer's ratings of more than 100dB, or supposedly comparative models to Celestion with higher ratings, with a large pinch of salt - most or all of them are optimistic. I don't know of any speaker which is genuinely louder than a V30 or a Gold in terms of perceived volume.

Are you sure that cab isn't a 2x10" by the way?! I had a Lead 30 a few years ago and it was. It doesn't look big enough in comparison to the T'n'B head to be a 2x12".

If you need 10s, Celestion G10 Vintage and G10 Gold are the equivalents. The G10N-40 and G10 Greenback are not too bad either, and a lot cheaper than the Gold.

Fatfingers

Thanks guys. The Greenback is 97db, so switching to a pair of 100db Alnico Blues should, in theory, double the volume, shouldn't it?

It's only an 18w amp, so a pair of Vintage 30s seems a bit over the top.

ICBM

Fatfingers said:

The Greenback is 97db, so switching to a pair of 100db Alnico Blues should, in theory, double the volume, shouldn't it?

It won't double the volume, but it will double the effective power of the amp, which will make it noticeably louder. You need 10dB more to double the perceived volume, by most measures.

Fatfingers said:

It's only an 18w amp, so a pair of Vintage 30s seems a bit over the top.

Yes and no. The actual rating is irrelevant, as long as they sound great at the power you're using. There are probably better-sounding speakers for a typical 18W amp though, I tend to find they work better with more powerful amps with more bass and treble content.

Blues should work great though, if you can afford them!

ecc83

If raw volume boost is your aim, multiple speakers are quite a help.

18W into a V30 is not pushing it that far into thermal compression but tis a bit so two of them could give you another couple of dBs.

Dave. 

MtB

I run my P1800 into a 1 x 12 Matamp cab fitted with a Celestion Gold, and it's plenty loud enough - hence my sig ; )

Fatfingers

ICBM said:

Blues should work great though, if you can afford them!

Yes. I've just looked at the price of them. A pair would cost me more than the amp! Still, I reckon they're spot on for what I need, so I best start saving.

ICBM

An option is to use one Blue and one other cheaper speaker that complements it well, like a G12H-30.

Fatfingers

Thanks for the idea. But would that give as much volume as two Blues?

Fatfingers

ICBM said:

Are you sure that cab isn't a 2x10" by the way?! I had a Lead 30 a few years ago and it was. It doesn't look big enough in comparison to the T'n'B head to be a 2x12".

Sorry - missed this earlier. Yes - it was a 2x10 cab. But when I got it it was empty, so I rejigged it for a pair of 12s.

Fatfingers

I'm thinking a pair of G12H-30s might be a more realistic option. Those Blues are just silly money. Unless anyone thinks they're really worth twice the money.

ICBM

Fatfingers said:

Thanks for the idea. But would that give as much volume as two Blues?

Yes - maybe even slightly more, perceptively. Both are 100dB speakers, although the Blue sounds louder on its own because it has much more upper-mid and that slight harmonic distortion, whereas the H30 is cleaner. But the Blue lacks bass a bit. So if you add them together you get the cutting upper-mid of the Blue but reinforced with more bottom-end from the H30, and it might even sound louder than two the same of either type.

Fatfingers

That sounds like just the ticket.

Thanks again, ICBM. 

ThePrettyDamned

ICBM said:

Fatfingers said:

Thanks for the idea. But would that give as much volume as two Blues?

Yes - maybe even slightly more, perceptively. Both are 100dB speakers, although the Blue sounds louder on its own because it has much more upper-mid and that slight harmonic distortion, whereas the H30 is cleaner. But the Blue lacks bass a bit. So if you add them together you get the cutting upper-mid of the Blue but reinforced with more bottom-end from the H30, and it might even sound louder than two the same of either type.

Slightly off topic, but what would the effect power rating be of this pairing?

It was what I was thinking of going for. 

ICBM

ThePrettyDamned said:

Slightly off topic, but what would the effect power rating be of this pairing?

It was what I was thinking of going for. 

30W. It's always the same as twice the lower-rated speaker, if the impedances are the same.

ThePrettyDamned

ICBM said:

ThePrettyDamned said:

Slightly off topic, but what would the effect power rating be of this pairing?

It was what I was thinking of going for. 

30W. It's always the same as twice the lower-rated speaker, if the impedances are the same.

Okay, cheers.

Fatfingers

I won a pair of used Vintage 30s on eBay for 100 quid. Hopefully they'll do the trick, for a lot less than Blues.