Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Vlada on September 29, 2018, 02:39:36 pm

Title: Preamp tubes rattling
Post by: Vlada on September 29, 2018, 02:39:36 pm

Hi there guys, recently I have bought some NOS ecc83/12ax7 tubes in original boxes from closed radio repair shop. Got them cheap. I sold my last build, now I am waiting parts for 50 watt plexi to arrive and don't have an amp to test those tubes. Some of tubes have a strange sound when shake I or tap them gently like rattling or hitting loose spring. Does this mean tube is bad?

Title: Re: Preamp tubes rattling
Post by: davidwpack on September 29, 2018, 03:18:34 pm

I've got 3 different amps with rattley rectifier tubes. Don't know why it's always the rectifier. But anyways, they all work fine.

Title: Re: Preamp tubes rattling
Post by: PRR on September 29, 2018, 06:08:56 pm

Don't throw them out. Yet.

Title: Re: Preamp tubes rattling
Post by: shooter on September 29, 2018, 07:22:51 pm

also, look really, really close, the obvious chunks are easy, the little pieces...