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Marshall 2204 sounds ugly, tubes?

3/8/2000 10:49 PM
Stefan	Marshall 2204 sounds ugly, tubes? Hello, My Amp sounds bad, but here is the story: After biasing my 2204 to 36mA, before it was 45mA, the sound of this amp is still bad. I removed the low input jack network and go now from the frist stage out via .022uF to the preamp-pot. The bad sound dont´t change. The power-tubes where changed 4 months ago and running all the time with the bias of 45 mA. The pre-amp tubes are now at least 9 years old but I thing, that they are still the first tubes, means 19 years old. The amp was not played often, maybe 1200 hours all over. Now I try to discribe the sound. On low vol. the amp sounds like it has a broken guitar cable connected. No attack, different output vol and sound (sometimes with distortion) depending how hard I play the guit. I try different wires and guitars and also speakers, no change. On all vol there is nearly now bass and no pressure,like singing with a blocked nose. (It´s allway´s very difficult to discribe a sound). What I want to do is: I´m on the wright way? replace the preamp tubes because of there age. witch tubes are good? (12ax7) if no help replace the power tubes because of the high current for 4 months witch tubes are good? (EL34) if no help I will post again, I think. Thanks a lot for your statements Stefan

3/8/2000 10:49 PM

Stefan

Marshall 2204 sounds ugly, tubes?

Hello,

My Amp sounds bad, but here is the story:
After biasing my 2204 to 36mA, before it was 45mA, the sound of this amp
is still bad. I removed the low input jack network and go now from the
frist stage out via .022uF to the preamp-pot. The bad sound dont´t change.
The power-tubes where changed 4 months ago and running all the time with
the bias of 45 mA.
The pre-amp tubes are now at least 9 years old but I
thing, that they are still the first tubes,
means 19 years old.
The amp was not played often, maybe 1200 hours all
over.

Now I try to discribe the sound.
On low vol. the amp sounds like it has a broken guitar cable connected.
No attack, different output vol and sound
(sometimes with distortion) depending how
hard I play the guit. I try different wires and guitars and also speakers, no change.

On all vol there is nearly now bass
and no pressure,like singing with a blocked nose.
(It´s allway´s very difficult to discribe a sound).

What I want to do is:
I´m on the wright way?

replace the preamp tubes because of there age.
witch tubes are good? (12ax7)

if no help
replace the power tubes because of the high current for 4 months
witch tubes are good? (EL34)

if no help
I will post again, I think.

Thanks a lot for your statements

Stefan

Replies:

Marcus Schantz You could have a bad preamp tube. C... -- 3/9/2000 12:02 AM
Trace q{I removed the low input jack netw... -- 3/9/2000 12:53 AM
Dietmar Hi This is exactly ... -- 3/9/2000 7:14 AM
Stefan prbl is fixed, bad tubes -- 3/10/2000 12:04 AM