#1
Is it possible to change a 100 watt amp to a 50 watt amp? I found a great deal on a 100 watt JCM 900, but I don't need something that loud. My plan was to convert a 100 watt head to a 50watt and install a half power switch. Is this possible? If so can someone explain how to do it?
#3
ive heard that if you take half of the power tubes out then the wattage will be half..but i have not a clue honestly since i have never tried it
Well, Jesus Christ, I'm not scared to die,

I'm a little bit scared of what comes after

Do I get the gold chariot?

Do I float through the ceiling?
#5
Yep. Yank two power tubes and cut the ohmage in half.
I'm putting my GAS on hold
for a couple months in order to pimp my ride.


Don't judge me.
#6
It will only be 3dB quieter than a 100W amp at the same setting. Really the wattage it doesn't matter for volume. If you want more power amp distortion, the lower wattage is great, but you'll still get plenty of preamp distortion at 100W. Pulling the tubes works, but some people say it ruins the tone of the amp. Unless you know that poweramp distortion is what you want, I would just leave the tubes in and run it at 100W.
#7
Attenuator would be the idea instead of modding a JCM, I'd say go for the deal and if you find it bad somewhere in the long run, sell it for a profit if you can get it for a deal.
#10
No, don't go on Musicians Friend. Go on weberspeakers.com. His are much, much better than a THD Hotplate, which is probably what you'll come upon on MF.

Quote by roshjosh
Would the removing of power tubes work for my 2x12 Crate V33?


Sure you can. Just remember that you have to adjust ohms accordingly. I wouldn't recommend it in a 2x12 Combo.
I'm putting my GAS on hold
for a couple months in order to pimp my ride.


Don't judge me.
#12
Quote by forsaknazrael
^I'm not so sure it would work. It's not for every amp. I would research it.

It would certainly reduce power, but you wouldn't be able to get the sound into the speakers anymore.
I'm putting my GAS on hold
for a couple months in order to pimp my ride.


Don't judge me.
#13
Quote by theoreticmusic
It would certainly reduce power, but you wouldn't be able to get the sound into the speakers anymore.
...That makes no sense.

If it's possible, you have to double the applied ohmage.

However, if your amp uses a shared cathode resistor which I imagine is likely, then pulling the tubes will double the current in the remaining tubes and burn them out rather quickly.

You need to find a schematic ideally.
The Laney Thread are big and clever. No exceptions.
#14
Quote by MrCarrot
...That makes no sense.

If it's possible, you have to double the applied ohmage.

However, if your amp uses a shared cathode resistor which I imagine is likely, then pulling the tubes will double the current in the remaining tubes and burn them out rather quickly.

You need to find a schematic ideally.

That's what I meant. I worded poorly. Adjusting the ohmage in that particular 2X12 combo would be tough/impossible.
I'm putting my GAS on hold
for a couple months in order to pimp my ride.


Don't judge me.
#15
Quote by theoreticmusic
That's what I meant. I worded poorly. Adjusting the ohmage in that particular 2X12 combo would be tough/impossible.
Yeah, so what you do is double what the amp thinks it's seeing.

For example on my Laney, usually you'd use 8 ohm with 8 ohm. But instead, with half the power tubes, you switch the ohm switch on the amp to 4 ohm and still use the 8 ohm load, which is the same as using a speaker with twice the impedance load.
The Laney Thread are big and clever. No exceptions.
#16
Ohmage isn't a word. Impedance is the word you are lookin for.

Edit: it is a word, but according to Matt Bruck, it shouldn't be used when talking about speakers.
Last edited by MAYNARD at Oct 2, 2008,
#17
Quote by MAYNARD
Ohmage isn't a word. Impedance is the word you are lookin for.

Edit: it is a word, but according to Matt Bruck, it shouldn't be used when talking about speakers.
Meh, pedantic much
The Laney Thread are big and clever. No exceptions.
#18
Quote by MrCarrot
Yeah, so what you do is double what the amp thinks it's seeing.

For example on my Laney, usually you'd use 8 ohm with 8 ohm. But instead, with half the power tubes, you switch the ohm switch on the amp to 4 ohm and still use the 8 ohm load, which is the same as using a speaker with twice the impedance load.

Right, but I'm pretty sure the Crate doesn't have an impedance switch. I double-checked, and didn't see one. Could be wrong though.

Oh, and to the gentleman who said that ohmage isnt a word, screw you. I wrote the dictionary.
I'm putting my GAS on hold
for a couple months in order to pimp my ride.


Don't judge me.