does replacing the tubes in an amp just improve the sound(if the tubes are really old) or does it raise the volume as well? is there anyway to modify an amp to make it louder? or would i be better off stashing away some money and buyu a better amp?

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i don't think it would affect the volume very much, if at all, but i'm not to sure.
how powerful is your amp(watts)?, and how many speakers are you pushing?

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only one, anbd its a shit box, i ocuslnt tell you how many watts, any way of figuring it out, i think id be better off just getting a new amp

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what brand? what model? i'm assuming its tube right?
more speakers will give you more volume, because they move more air.
higher wattage usually helps to acheive more volume. and whether or not the poweramp section of the amp is tube or ss will also have an effect on volume.

and it will prabably say somewhere on the back of it what the wattage is.
how loud do you need to be?

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More speakers wont always make it louder. It depends if your amp has enough power to even push more speakers. If you power a second speaker with a little combo amp the volume will probably actually decrease because its splitting the wattage 2 ways instead of one. Also, you cant really push a stock speaker beyond its power rating (which should be stamped on the back of the magnet). What size is the original speaker, what brand is the amp....? Need more info to help you out.

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get a 15w 8'' combo to push a 4x12 cab and you'll see what i mean.

more speakers will move more air, so a 4x12 will make it louder all together. but since the power is split, each individual speaker won't get as loud as that one 8" speaker with the whole 15w going to the one speaker. just the fact that there are 4, 12" speakers working together,pushing more air, and producing a certain amount of sound can make it quite a bit louder.
its very complicated, i understand what you're trying to say, but just because it's split power doesnt mean it wont be as loud.

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though, if you have too much speaker surface your amp can handle it'll still sound like shit.

same goes for old tubes. replace them with DESCENT tubes, not that chinese crap, get some Sovteks or JJ's!

but first... tell us more about the amp and which tubes it uses.

So your saying, for example, my jcm900 cab (4x75watt speakers) can be powered by a 15 watt amp? I dont think so. If you take electronics engineering for 3 years you might think differently too. You should probably try that one first.

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he didnt say that

and yes... YOUR JCM900 CAB can be powered by a 15w amp!

even better, my preamp can power a JCM900 cab! (1,5wx2 tube power hell yeh) and it sounds descent! (room volume)

ofcourse its not loud

you might not "think so", but i "know so".
personal expereince.
in an older band of mine our other guitarist had a 4x12 cab, and he was saving up for a head, until he got it, he used a 15w 8" crate combo amp to push it.
just because your cab can handle 300w doesnt mean you need 300w to power it,for example your head that you're currently using is probably only 100w, and it will push it just fine.
so if your "electronics engineering" class told you a 15w combo couldnt power a 4x12 cab, i'd go somewhere else for my education.
15w pushing a 4x12 might not be as loud as a 100w head, but it ---WILL--- power it. otherwise, what would be the point in putting a speaker jack on a little combo?

i wasnt and still am not trying to make a personal attack on you. facts are just facts.

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No i understand what your saying but from my personal experience it doesnt work.I agree completely that it WILL power it, but it wont be as loud as the original speaker is what im trying to say.
No offense taken, its a good discussion.



This is where the problem is i think.... You say that the 4x12 will make it louder altogether. But you say each speaker wont get as loud as the one 8". But i see what you mean now, that if you add up all 4 speakers, it could be louder.
That depends on the resistance and wattage (RMS and max.) of the speakers that your using too. This could go both ways depending on the equipment being used.

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that whole bit about how a 15w combo not being able to power your jcm 900 cab is what i had to argue with.
and then you tried to act like you had some super smart education that could prove it. whether or not you do have 3 years of electronic engineering, a simple "try it out for your self" job, could easily PROVE a 15w combo will power your jcm 900 cab.
its like if you have a 100w head pushing your 4x12 cab, then when you add another 4x12 cab, the head now has to split the power between more speakers. so its still only 100w, but instead of pushing 4 12" speakers, you have it pushing 8. and i garauntee that will be louder, not twice as loud or anything, but even if you had a 200w head pushing 2 4x12 cabs, it wouldnt be twice as loud as 100w pushing one 4x12 cab. but it would still be quite a bit louder.

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ahem, I agree with the small combo beeing able to push the cab.

but... more speaker surface doesn't actually mean its going to be a hell of a lot louder, your amp has to drive more speakers and is under a more heavy load simply because it lacks power, at high volume it'll break up (thats what I got from experience) however a 4x12 sounds louder like a 1x8 in perception because the 4x12 spreads the sound much better, its not allways louder, the perception is pretty important too. my preamp powering a 2x10 cab sounds ok, when powering a 4x12 it sounds thin but the sound is spread much better

This is not true in all heads, but it sure means something in poweramps, when you add another cabinet, it cuts the ohm load down to half which makes the the amp have to work harder, usually twice as hard. That's why you see 100w at 8ohms, 200w at 4 ohms, for example, on the back of amps. It will get louder but not twice as loud if you do this, usually about 3dB. One reason it will sound louder going from a 1x8 to a 4x12 is that more speakers means better frequency range, bigger speakers means more bass, bigger cabinet means more bass and low mids. If the ohms load is the same, it will not unnecessarily stress the amp just because it means more speakers. And I have proof that you can run a 4-12 on 1 watt! Go here and watch the demo video. By the way these are the coolest things on the planet.

http://www.smokeyamps.com/Smokey_Pages/smokey.html

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I said 4-12 but it looks like he is using a 2-12. But you'll just have to trust me on the 4-12, I've got 2 of these things and yes it will push a 4-12.

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