StewMac

Amplifiers that use adjustable fixed-bias should be checked and adjusted when changing power tubes. This will allow your amp's power section to function...

Installing new tubes may improve the performance of your amp, especially if it has been played a lot! Power tubes wear out with use, and they need changed o...

In most cases, any 12AX7 tube can replace any other 12AX7 preamp tube. Some brands of 12AX7 tubes have different frequency response, different constructio...

Our recommendation is to check the current tank, if possible, and compare any alpha-numeric labels to the model numbers listed on our website. You may also ...

StewMac tech, Tommy Stumpp, shows you step-by-step how to build our Tweed 5F1 amp kit. In this 5-part series you'll learn everything you need to know to...