Amplifier speaker relay problems.

I'm not familiar with the circuitry of your amp but I suggest checking more deeply arround the ciruit board for the following possible failures:

This relay faliure can be on more reasons than you might think of. Relay can also block an input stage thus blocking any signal that is about to enter the blown output stage.

I'd suggest checking output devices since often fuses can act too late to protect and Relay is acting only after the output stage is blown. Please note that relay in this case shunts the signal(and/or power supply to the output stage) through the load resistor and depending on time of such task can also be blown along with load resistor.

To check your output devices remove relay to connect directly and use dummy load 50W/10Ohms resustor to MEASURE DC from the binding posts. You can end upto 30V that can blow the speaker in the flash even after you replace relay wihtout checking out all possible failures.

Possible reasons for output stage failures:
--Bad trim pots that adjust the emitter(or channel) bias.
--Surge or voltage jump(s).

Thank You for your reply, I did not realize that this relay also may offer protection, Though I am sure it is a mechanicle/contact problem with the relay itself do to the fact that if I tap the relay on top the chanel restores.
Thanks again, Guycom

You can do much better without these relays and opt for smaller output fuses i.e. .5A instead of 2A. Thus you will increase resistance on the signal path but along with that elimintate the switch that impacts synergy much larger.
You can get high quality ceramic fuses from www.mouser.com for pennies.

So Just let me know if I have this correct. Remove the relay and run the two normally open swich legs thrue a 1/2 amp fuse.
Thank You,
Guycom

Guy this is so easily fixed. All you need to do is burnish the relay's normally open contacts, which are now dirty & degraded from the years of use. Go to Radio Shack or check their website for a relay contact burnishing tool. These are like a very fine nail file, but are coated with diamond dust on both sides. You simply insert the spatula end in between the contacts, then apply finger pressure to the relay armature to hold the contacts against the tool, then file with an in/out motion. If both sides of the tool aren't abrasive (some are / some aren't) then turn it over & do the opposite contact. Spray or hand apply some good oilfree contact cleaner afterwards. Crocus cloth (a very fine abrasive) found in better hardware stores will also do a good job, & is cheaper too.