It never ends ...No horns on one channel

[hermitcrab]

I am done with these piece meal fixes only to have another problem crop up a month or two later...playing music on the magnavox and I noticed the brightness was low... there is nothing out of the right channel as far as horns... the woofer is doing it all... the crossover caps test OK ...so I put a ohm meter on the horns.... open... both of them! ordered 4 new pyle horns from parts express ... plus new caps ... I am changing them on both channels ... no more fixing one side only to have the other side quit six months or a year down the road... people laugh at guys the shotgun caps into equipment... from now on that is going to be my mantra ...after all this stuff is going on 60 years old ...it is getting to the point where you almost need to strip the PC board and rebuild them completely with new components... these things are like old cars... they will nickel and dime you to death...

[maxidyne]

I always shotgun capacitors. If one is bad, they all are. Even then, it seems like there is always something wrong.

[electra225]

Could there be something amiss that is blowing both horns? I'd be interested in knowing more about what took the horns out. Do they just quit without warning?

[TC Chris]

HF speakers can be burned out by an amp that's overdriven into clipping. Clean power does it less often than underpowered amps. Or maybe there' some sort of HF oscillation, above the horns' actual response or beyond our hearing range?

I grin when I say "our" hearing range. I mean "normal humans," not "older males like me who have lost HF response."

Chris Campbell

[electra225]

One would think that if you were driving an amp in a console stereo to clipping, enough to blow horns, there would be some type of "marital discord" from running it so loud.....

Could leaky electrolytic caps someplace in the amp cause the horns to burn out?

[hermitcrab]

This console never goes past the half way point on volume ... you couldn't stand it...I wondered why both were reading open as well, only thing I could think of was if the low hum from the Bass couplet was the problem or not... it hummed for over a year before I figured out it was the couplet ...I rebuilt that to fix the hum... thinking maybe I should rebuild the other couplet on the treble as well ...like I said fix one problem another pops up...

[electra225]

I have never had an issue with a couplet, so I'm not sure I can help you much there. The only couplets I'm aware of being problematic are in Predicta TV sets, which your console ain't one of. You are more familiar with solid state devices than I am, but my understanding is that replacing the electrolytic caps in the audio section is often mentioned as the fix for such problems. Have you done this or considered it?

I have an RCA (Radio Shack) graphic equalizer I used with my Pioneer SX-1050 to process music to digital. You can clean up old scratchy records, mainly 78's, with a good equalizer. I lost the left channel to my stereo, blamed it on the SX-1050. Turns out, the equalizer was the problem. I opened the cabinet and found bulged low-voltage electrolytics actually in both channels. Two in the problem channel, one in the "good" channel.

I have always considered solid state equipment to be more reliable than tube. Perhaps age is catching up with the solid state stuff by now and they have issues like the tube stuff does. Contacts and connections seem to be the most prevalent problems with tube equipment, once you go through them thoroughly. Controls, function switches, speaker switches, balance controls, tube sockets.

[Motorola minion]

I use a set of Magnavox horns on my garage speakers. These are two Pyle 12" woofers and a crossover that I designed for using the Magnavox 580069 horns.

I have not blown one yet and suspect you may have a crossover network that could let too much low frequency through to the horn.

While your crossover may be stock and thus correct, crossover caps can leak just as easily as they open. I find some that read higher than stated value on my ESR tester, which indicates GOING leaky. Most have DC voltage ratings but that is not what is being applied. 100 volts is pretty standard. There are also resistors to limit current on many Magnavox crossover networks.