I have a Goliath II that I got cheap because the fuse (light bulb) was blown, and the guy didn't know if the horn was good or not 'cause he'd never replaced the fuse. Got it a few months ago, played it as-is since then. My hartke 7000 puts out a pretty crispy tone, so I didn't miss the horn. I finally located a replacement for the fuse in question, popped it in, and Volia! Nothing. - If I smack a 9v against the terminals of the horn I get some static, so I know the horn isn't totally dead. - If I wire the horn directly to the inputs it just puts out lots of fuzz. - If I wire the horn behind the first electronic bit (big yellow barrel, doesn't look like a cap, possibly resistor) I get nothing. - The circuit goes about like this: Input splits, half wired directly to woofers (4x10, 4 ohms), other half goes into treble crossover for horn. -> two yellow barrels (series) -> wire inductor coil -> big 'ole level knob (pot) -> horn 1. Inductor coil wired in series, would give us a 1st order band-pass filter. 2. If inductor is wired in parallel as a high-pass, yellow barrels must be caps a-la a second order high-pass. (http://www.termpro.com/articles/xover2.html) This cab lives at my practice space, so I'm taking my multimeter and some test leads with me next time I go over there, but I'd LOVE any info you guys can give me. I have no idea what those yellow barrels are (I'll get photos), and I can't figure out why the horn wired directly to the inputs was fuzzing so badly when the woofers were chillin quietly.