amptech question: tubing a fireball - please help

hoehlentroll · June 4th, 2012, 05:27 AM

I read that the "grading" systems makes retubing a piece of cake. I opened the amp and found this:

I bought the amp new in local store and the tubes where stock. the tubes are about 5 years old

*i know, I know*

1. what does the different tubing do to the sound?
2. could this by any means be NO fault?
3. what should I do now? a. buying grade 22 or 27 or b. take the amp to a tech which means LOADS of money. I live near Tube Amp Doctor (TAD-tubes).

I have no fucking idea of how to bias a tube amp!

EDIT: funny thing: http://www.urbandictionary.com/define.php?term=tubing

TheWinterSnow · June 4th, 2012, 09:18 AM

The grading number is simply the amount of idle current that the tube will conduct when the tube is placed in a typical amp. Higher numbers means that the tube will run a little warmer. You should pick up a matched set, meaning that they are the same or one number off, just buy a set of matched tubes, put em in and be done with it.

June 4th, 2012, 05:27 AM	#1 (permalink)
hoehlentroll Senior Member Join Date: Mar 2007 Location: Mannheim, Germany Posts: 1,715	amptech question: tubing a fireball - please help I read that the "grading" systems makes retubing a piece of cake. I opened the amp and found this: I bought the amp new in local store and the tubes where stock. the tubes are about 5 years old i know, I know 1. what does the different tubing do to the sound? 2. could this by any means be NO fault? 3. what should I do now? a. buying grade 22 or 27 or b. take the amp to a tech which means LOADS of money. I live near Tube Amp Doctor (TAD-tubes). I have no fucking idea of how to bias a tube amp! EDIT: funny thing: http://www.urbandictionary.com/define.php?term=tubing __________________ Free Kick Sample (HoehlentrollDAKick) My band's debut album as digital copy on bandcamp. 13 tracks old school death/thrash/grind. Compulsive Slaughter - Breed Out The Bastards Last edited by hoehlentroll : June 4th, 2012 at 05:39 AM.

June 4th, 2012, 09:18 AM	#2 (permalink)
TheWinterSnow Den Mørke Natt Join Date: Oct 2008 Location: Sacramento, CA Posts: 2,884	The grading number is simply the amount of idle current that the tube will conduct when the tube is placed in a typical amp. Higher numbers means that the tube will run a little warmer. You should pick up a matched set, meaning that they are the same or one number off, just buy a set of matched tubes, put em in and be done with it. __________________ Corvus Audio -Now Available: Loadboxes w/ active line out -Now Available: 5150/6505 Bias Mod Kits -In the works: DI + Reamp box -In the works: Cabinet Impulses and Reactive Load Impulses -For custom electronics, mods and repair, email: CorvusEngineering@gmail.com My band's Facebook Download our EP