Marshall JCM 800 2203 RI - reduce power?

[MicSlut666]

Is it possible to pull two power tubes at the Marshall JCM 800 2203 Reissue to reduce the power from 100 Watt to 50 Watt. Will this work without any adjustments regarding Bias... ? If possible should the inner or outer tubes pulled out? Thanks!

 

[Wolfeman]

Pull opposing pairs, and remember that the output transformer changes when you pull them.

 

[VH100R]

pull the two inner tubes or the two outer tubes.

when running @ 50 watts you will have to adjust the impedance.

so:

amp @ 100W with 8 ohm cab -> use 8 ohm speaker out (no tubes pulled)
amp @ 50W with 8 ohm cab -> use 4 ohm speaker out (2 tubes pulled)

amp @ 100W with 16 ohm cab -> use 16 ohm speaker out (no tubes pulled)
amp @ 50W with 16 ohm cab -> use 8 ohm speaker out (2 tubes pulled)

 

[Metaltastic]

WAIT, really? I thought it was the other way around (amp @ 50W with 8 ohm cab -> use 16 ohm speaker out (2 tubes pulled))

 

[VH100R]

mnemonic:

half the power, half the impedance.

 

[mick thompson]

if your trying to drop your volume but keep your kranked tube sound without having to fork out on a hotplate try putting a passive volume control into your effect send/return - thats what i do to my peavey 6505+ and it works perfect

 

[VH100R]

if your trying to drop your volume but keep your kranked tube sound without having to fork out on a hotplate try putting a passive volume control into your effect send/return - thats what i do to my peavey 6505+ and it works perfect

since the FX loop is before the power amp stage, that does nothing to get the power amp juice we all love on a cranked amp.

But if it works for you, do it!

 

[MicSlut666]

Thanks for the great feedback so far