#1
I'm replacing the tubes is my 6505+ for a warmer creamier tone. All the kits I've looked at include 6 tubes, when I look in the back of my 6505+ I only see 4. I assume the 2 others are under those big box things on the left and right.

(realise that is a 6505, but it has the two "box" things I'm talking about)

How do I get into the boxes to replace the tubes?
Mesa Single Rectifier
Marshall 1960A vintage
Rg3exfm1 w/ EMG 85/81
Big Baby Taylor Acoustic
Ibanez TS808
#3
then where the junk do the other 2 tubes go?

"Peavey 5150 II - 6505+ KT66-6L6GC Option
Description: We finally got around to an Integrated quad for the 5150II or 6505+ amps! This kit uses a pair of JJ KT66's for the outside two sockets and a pair of 6L6GC's for the inside two sockets. The KT66's have a big fat tone with a very creamy high end and a smooth breakup so the mixture is pretty cool. This kit uses a standard front end with five ECC83S's and a balanced ECC83S for the phase inverter."
Mesa Single Rectifier
Marshall 1960A vintage
Rg3exfm1 w/ EMG 85/81
Big Baby Taylor Acoustic
Ibanez TS808
#4
lol at the "two boxes" those are the power and output transformers.


100 watt amps use 4 power amp tubes.


It uses 6 preamp tubes. They might be under the chassis, I wouldn't advise you go in there yourself, especially considering you didn't know what the transformers are. There are lethal voltages inside the amp that can and most likely will kill you if you touch at the wrong places.
Last edited by al112987 at Oct 22, 2008,
#5
the ECC83** are the preamp tubes, they are 9 pin and much smaller than the power tubes in the picture. the ones in the pic are bob's integrated quad of powertubes. There is a cover on the right side, looking at the back of the amp, that you unscrew, and you can then see the preamp tubes.

you can see the cover off on this pic of the back



btw, you might want to research some more on those integrated quads. Those KT88 are going to be running way way cold in those amps unless it's been modded like the one in your pic. I can see 2 pots sticking up next to the tubes, which I assume are for biasing the pairs.
"The fool doth think he is wise, but the wiseman knows himself to be a fool." - W.S.
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#6
Ya, I planned on having a professional do the bias
Mesa Single Rectifier
Marshall 1960A vintage
Rg3exfm1 w/ EMG 85/81
Big Baby Taylor Acoustic
Ibanez TS808
#7
They're KT66s, not KT88s.


edit: nvm, they are KT88s my bad.


KT66s should work fine though, I always thought they were pretty mcuh interchangeable with 6L6s.
#8
Quote by al112987
They're KT66s, not KT88s.


edit: nvm, they are KT88s my bad.


KT66s should work fine though, I always thought they were pretty mcuh interchangeable with 6L6s.


Oh.. so i wouldn't need a bias adjustment?
Mesa Single Rectifier
Marshall 1960A vintage
Rg3exfm1 w/ EMG 85/81
Big Baby Taylor Acoustic
Ibanez TS808
#9
Quote by al112987
They're KT66s, not KT88s.


edit: nvm, they are KT88s my bad.


KT66s should work fine though, I always thought they were pretty mcuh interchangeable with 6L6s.

yeah, his kit for the 6505+ uses the KT66, the 5150 in his pic though has the 6L6 + KT88 integrated quad. The KT66 are drop in replacements afaik, not sure what kind of plate current they draw to be biased correctly though.

Quote by touji-za-nai
Oh.. so i wouldn't need a bias adjustment?

you should still have it biased.
"The fool doth think he is wise, but the wiseman knows himself to be a fool." - W.S.
amp clips
amp vids
Last edited by Erock503 at Oct 22, 2008,