Problem Speaker Cabinet?

[bassman134]

Hi,

I have a potential issue maybe someone can offer advice on.

Rig: Hartke HA3500, bottom is a Schroeder 1210, the kind with the folder back 10" and the variable control for the tweeter. I use a standard 12 or 14AWG speaker cable 1/4 inch ends.

Problem:My Hartke HA3500 started blowing the main fuse, its about 7 years old. About a week before it died, I turned it on and when I went to play, it sounded like a had a blown speaker, kind of distorted low sound, like if you tried pushing the signal through an instrument cable. I swapped out the speaker wire, no fix. I turned the amp on/off and the issue went away. About a week later, the fuse thing started.

I am now using my 20yo Peavey backup, and I had the same issue. I got very low distorted volume. I quickly shut everything down. I checked the cable, no shorts. I ohmed out the end of the cable with it connected and it came up around 4.6 ohms (4ohm cab). (edit) It didn't happen right away with this amp either, was working fine for a few days and then happened.

I turned the amp back on, and it was fine. With it hanging on the wall, banged out a note and proceeded to wiggle the speaker wire and turn and wiggle the control on the cabinet. All worked fine.

Can I have an intermittent problem in the cabinet? I just ordered a new Portflex 500 to replace the Hartke (Yay!) but am worried there is something up with my cabinet. I would imagine speakers are either good or bad, correct? What should I look for other than a loose wire (gonna open up the back tonight).

Also, Initially with the Hartke swapped out the instrument cable and Bass.

Thanks

[will33]

Yes, check the little easy stuff first, intermittent connections, cracked plastic jacks, etc.

[bassman134]

Well, I think I found it. The pot for the tweeter is really large, and was loose. I noticed it a while ago, but never thought it could be a problem. The terminals on the pot could easily come in contact with the speaker terminals. Not sure if this would cause a short but it can't be good. I spun it around, tightened it up so the terminals are opposite the input jack. I also taped over the terminals just in case it comes loose again. I'm going to get some lock-tight and put it on the control nut. Some heat shrink would have been a good idea on these terminals.



That control has been loose for a while, just too lazy to look into it, I guess I learned my lesson this time. In the picture I had already turned it, when I opened it up it was turned so all three of the terminals were over the input jacks.