Plexi 100: crackling and hiss, small booms...

[Twistingcrow]

How do you know the tubes are good? This has tube written all over it. I'd start there.

When the cap failed many other parts were also stressed. Dont take anything as good until prove it. Culd be hard to troubleshoot, but you'll find it.

Those CE caps tested better than JJ's on my cap tester. First time I've seen one blow up. Sorry for that.

George

Well, I swapped the four JJs that were provided with the kit for 4 Shughang EL34s provided by tube tramp. Plus I swapped one preamp tube after one preamp tube for a stock EH 12AX7...

I'll keep trying but I can't figure this out. Booms have disappeared but I still get too much hiss. When I don't touch the amp it's relatively quiet, but it's hiss nightmare when I turn either the bass or treble pots...

[Twistingcrow]

I found this thread at last!
http://forum.metroamp.com/viewtopic.php ... TS#p284258" onclick="window.open(this.href);return false;

So I changed the 500pF black SM treble cap. Problem solved. I took the 500pF volume I cap out as well. I like the sound better.
The amp is repared and back to great sound and low noise! Rock'n'roll time!

Thanks!

[toner]

Didn't someone suggest checking for DC on the treble pot? Who was that? Oh yeah, me. Just kidding. Glad you found it!

[Twistingcrow]

Didn't someone suggest checking for DC on the treble pot? Who was that? Oh yeah, me. Just kidding. Glad you found it!

Yeah, thanks a lot toner... I listened to you but I tried that with the amp OFF... It was obviously to try with the amp full ON... Oh well, you never stop learning... But thanks a lot toner!

[syscokid]

Didn't someone suggest checking for DC on the treble pot? Who was that? Oh yeah, me. Just kidding. Glad you found it!

I think, in another thread, novosibir had a preference over one brand of SM's compared to another due to durability issues. I can't remember which brands he was comparing...
Maybe someone can add to this response?

[JimiJames]

I found this thread at last!
http://forum.metroamp.com/viewtopic.php ... TS#p284258" onclick="window.open(this.href);return false;

So I changed the 500pF black SM treble cap. Problem solved. I took the 500pF volume I cap out as well. I like the sound better.
The amp is repared and back to great sound and low noise! Rock'n'roll time!

Thanks!

Awesome ! Let'er rip !