Here is a great example of a badly microphonic power tube. When the amp was played, this tube would vibrate and create a very annoying rattling noise through the speaker. This tube is BAD and must be replaced

NOTE: Touching a tube and leaving finger prints WILL NOT damage a tube. Finger prints, paint, grease, dirt, etc. on the glass WILL NOT cause the glass to fail. Power tubes are NOT like high vacuum light bulbs. Contamination on the glass surface WILL NOT cause a hot spot and ultimate failure of the glass.

свернуть