5150 - Removing half the power amp tubes ???

[lepard]

I know people sometimes remove 2 of the power amp tubes on 100W Marshalls to turn them into 50-watters so they can push the amp harder and have it not be as loud. Can I do this on a Peavey 5150 head ? I get a better low volume tone out of my 60-watt 5150 Combos than I do with my 120W 5150 head. You have to turn the head up to where it's too loud for bedroom use.

Excuse me if I've stated anything wrong here, I'm not an amp guru. Feel free to edjumacate me.

[Electric]

I believe you can safely run a 5150 by pulling the outer 2 or inner 2 6L6's, but you won't see much of a volume drop. You will get into power amp distortion more quickly, but any volume differences will most likely be negligible. If you do this you will need to change the impedance (if you have an 8 ohm cab, you would need to select 4 ohm on the back of the amp).

[charvelguy]

3db difference. You might be better off by getting an attenuator, a load box or running tube convertors. I have good luck with GT's 928PR. If you pull two, you should rebias the plate voltage as pulling two power tubes will effect the overall pv and it also alters the output impedance - it doubles it. So you'll use the amp with the impedance out switched to 8ohm out into a 16 ohm cab or 4 ohm out into an 8 ohm cab. You can run two outer pair or two inner pair.

[Hellbat]

I think attenuator is the way to go like charvelguy said. Pulling the tubes will give a volume drop but 50 watts will still kill the neighbors kids at anything over 5. Plus any time you want to go back and forth between 2 and 4 tubes you will need to adjust the amp. It's not plug and play like an attenuator.

[lepard]

OK, thanks guys. I just recently biased the thing up to 38mA and don't want to screw with that again. Any recommendations on an attenuator ?

[Hellbat]

I'm sure more experienced people will chime in, the only one I'm really familiar with is the THD Hotplate. I don't know how it stacks up to the competition though.

http://www.thdelectronics.com/product_page_hotplate.html

[horns666]

I had FIVE 5150s and played a shit-ton since.

I tweaked my kid's 6505+ 60w 1'12 combo..

with that said...would you take one ball outta your sack...pull a couple plugs from your Vette...take one titty off....poke one eye out.? Huh...didn't you see what happened to Black Mamba..???

[DonP]

I agree with Horns. In order to cut the volume in half, you need to reduce the power by 10 times. A 10 watt amp is 1/2 as loud as a 100 watt amp. 50 watts is only slightly different than 100.