Hello UG.
Here's hoping someone here can help me; I am having a problem with a hissing tweeter - I have used the search bar and found a couple threads that relate, but none with an answer or a good explaination of the problem.

I recently bought a Yamaha BBT500H bass head with a matching 4 x 10 cab. The only problem I am having is that even with the tweeter on the cab at a mere level 1, there is a continuous hissing sound, even with every eq and knob turned down to 0 - on the head and my bass, as well as unplugging my pedals and bass completely.

Any help would be greatly appreciated, as I really do enjoy the color of my tone with this tweeter active. Thanks in advance!