The HT-5 is Fragile. CAUTION!

[RollTide05]

Ok, I just have to post my experiences to warn other HT-5 owners about how fragile this amp is. Let me just say that I absolutely love (loved) my 2 amps, yes thats right, 2 so far and I am expecting my third unless they will only repair my amp head.

First, do not try to swap the tubes yourself! I will admit that I have had issues with my Marshall when swapping out the tubes, but this amp broke when I attempted to change the pre amp tube. I started pulling on it to replace the stock 12ax7 with a Tung-Sol and it was in there very tight. I actually got a bit scared and decided to just leave it alone because of my past experiences with tube swaps. I then pushed the tube back in firmly to re seat it, even though it didn't really move to begin with. When I turned the amp back on it squealed like a stuck pig on the o/d channel at all volumes. It is unplayable with a constant, loud feedback and when I began to play the tone sucked and was fizzy. What the heck? I never even unplugged the tube! The exact same thing happened to me when I changed the pre amp tube in my Marshall AVT20XT...twice. Am I an idiot, am I unplugging the freaking tubes wrong? I think I am forever doomed with tube swaps and tube amps in general. I know about microphonic tubes, how to test for them etc. and that has never been the case in these situations. I think by unplugging the tubes I have broken a solder joint or somehow broken the board. Why are tube amps so damn fragile?

Second, the speaker plugs on the back of the amp do not hold the speaker cables firmly. Be warned! On my first HT-5, the cable had come unplugged without my knowledge, I turned the amp on , got no sound then turned the volume up and down. I then plucked the strings and then turned it off. I realized that the cable had come unplugged and when I played the amp it sounded like total crap. It had become fuzzy and noisy with no compression. I think it messed up the output transformer.

Just wanted to warn everyone about these amps and how fragile they are. I hope this post will help others to not have the same experiences as me.

[ffooxx]

Sorry to hear that, but is quite odd, I have the amp for more then year now and no problems at all, change the preamp tubes back and forth as well as the power tubes without any issues.
The amp goes with me everywhere so it is constantly in transport nothing is loose everything works just fine.
Maybe you just had a really bad luck and those amps slipped trough the QA

[sleepeatplay]

I have 2 Ht-5-H heads. Swapped out preamp tubes with no problem. I also make sure the power supply is unplugged from the outlet. Any amp has a tendency to vibrate things loose. Also try being delicate replacing the tubes. Been doing tube swaps on amps for over 30 years without a problem.

[RollTide05]

See, this is what I am talking about. Everyone swaps tubes out on their amps...you eventually have to when they wear out anyways. I just absolutely don't get it man. Literally everytime I have touched a tube in any of my amps, it has broken the amp. I agree with ffooxx's comment man, it has to be some weird bad luck. I have learned my lesson this time. I will never touch one myself again. Anyways I hope this post is helpful to others who are prone to bad luck.