.:.:.:.:RTTP.Mobile:.:.:.:.
[<--back] [Home][Pics][News][Ads][Events][Forum][Band][Search]
full forum | bottom

---

Reply
[login ]
SPAM Filter: re-type this (values are 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E, or F)
you are quoting a heck of a lot there.
[QUOTE]blah blah blah[/QUOTE] to reply to brian_dc.
Please remove excess text as not to re-post tons
message
[QUOTE="brian_dc:491851"]something I found...granted just a music board post, but this should back up the idea of taking it someone. "Unless you are experienced with electronics and high voltages, this is something you should not do yourself or you might die. Take the amp to a tech to have it done. Biasing is making sure the correct voltage is applied to the power tubes (preamp tubes don't require biasing). Different tubes have different bias points. Unless you are replacing tubes with the same tubes from a supplier who measures their tubes for consistency (like Groove Tubes), you need to rebias every time you put in new power tubes. An underbiased amp will sound thin and weak. An overbiased amp will sound muddy. If too much voltage is applied to the plates, the tubes will burn out (and quite possibly take parts of the amp with them). On most modern amps, theres a potentiometer somewhere in the circuit that regulates the bias voltage. Depending on the method used (in the amp geek world there's a lot of controversy surrounding the best way to bias an amp), the amp is hooked up to an oscilliscope and signal generator or a multimeter and the pot is turned until the desired bias point is reached. Some amps (Mesa/Boogies, a lot of Fenders) don't have a bias adjustment pot. They have a resistor that must be replaced with one of a different value. If you are good with electronics and have worked with high voltage, this is something you can do yourself as long as you are VERY, VERY CAREFUL. There are numerous resources on the net that describe the various methods. I prefer the transformer shunt method." [/QUOTE]

top [Vers. 0.12][ 0.005 secs/8 queries][refresh][