Audio troubleshooting

[HighTekRedNeck]

Hello,
I'm obviously a noob here, but I enjoy fixing almost anything.
I have an active speaker with high end hum. I know , because I've isolated the noise to my inputs on my circuit board. I cannot find any obvious bad joints or capacitors.
The mfgr doesn't make or sell boards for this model. RS415 (Gemini)
I'd rather not trash the whole thing or start randomly replacing Capacitors yet.
Thanks for the help!

 

[duke37]

What is high end hum?
If it is mains frequency hum, then the reservoir capacitors (the big ones) have probably "gone off".
You can test this by putting a good capacitor in parallel with an existing capacitor, If there is an improvement, then replace the old capacitor.

Can you get a schematic?

 

[HighTekRedNeck]

What is high end hum?
If it is mains frequency hum, then the reservoir capacitors (the big ones) have probably "gone off".
You can test this by putting a good capacitor in parallel with an existing capacitor, If there is an improvement, then replace the old capacitor.

Can you get a schematic?

Thanks for the reply. The hum is only from the tweeter. Goes away when I unplug the tweeter. Yes I have a schematic.

 

[shrtrnd]

I'd check the grounding. Any grounds to the speaker housing, or possible short inside the tweeter?

 

[HighTekRedNeck]

Good points. I forgot to mention I did have a ground junction to the heat sink that had continuity. The tweeter is new since I blew the last one.

 

[Wayne Phillips]

Remove the leads to the tweeter and check if there is any dc volts as this will damage it.

 

[Audioguru]

Hum is a low frequency. Buzz is a higher frequency and hiss is a very high frequency. A tweeter does not produce low frequency hum.

 

[Wayne Phillips]

High tek red neck..

Do you have a scope to check the circuit out.

Also just replacing parts here and there will waste time.