SCIENCE Street Sweeper MkII User Manual page 8

Tip: If you think you have a microphonic tube, you can very gently tap on each tube with a pencil's
eraser to see if the sound becomes worse, stops, or changes. All tubes will amplify the sound of a
tap little, especially preamp tubes, but for example, if you hear an intermittent ringing sound and
tap each tube to find V7 (for example) is causing the ringing to start/stop, you can be sure it's the
problematic tube!
•
•
•
•
•
6