Hi folks, this is a strange problem I've never come across before. I stuffed a YJ tpa3116 ( black/blue) board in an enclosure with a 2 way input selector switch and a 10k tocos cosmos pot. I've used this setup before without problems but this time I'm getting quite a loud hiss from both channels that isn't coming from a source and dies away to almost nothing when the pot approaches max (nothing playing) in the max position the hiss can only be heard with my ear to the speakers but at normal listening positions I hear the hiss from my chair across the room. The same pot worked fine previously with a buffer so I'm kind of confused why it's not ok with the the amp board. I have a 20k miniature stepped attenuator I could try but I can't see how that would make any difference. Any ideas would be good to hear as this is both annoying and confusing.
Cheers D
Cheers D
Ok I got it sorted. I removed both the selector switch and the tocos pot. Its now got a single input and a 20k miniature dact stepped attenuator. I also replaced the twisted twin signal wires with screened mic cable. Its now almost silent even with my ear pressed against the tweeters and it's a more user friendly adjustment. The 10k tocos pot went too loud far to early in it's travel. Another gain is it's lost that annoying speaker pop it had on switch on. Think it might have gained slightly sonically too but I'll need to listen to more tunes before I can confirm that.
I still don't not know why it was behaving so strangely but I think it was probably that tocos pot at fault. It's in the bin now so I don't try using it again lol. D
I still don't not know why it was behaving so strangely but I think it was probably that tocos pot at fault. It's in the bin now so I don't try using it again lol. D