Hi guys.
I took apart a rubbish Power Dynamics amp and put the bare bones parts in a nice small chassis. I have a song by John Foxx of Ultravox which I use for testing. The track Metal Beat from his 1980 album Metamatic.
His lyrics travel from channel to channel back and forth. Please forgive my lack of knowledge. This is my third amp build, and the only one I'm struggling with.
Basically half the lyrics are missing. From 40 seconds on it's very clearly wrong.
I'm hoping from the following photos of the layout someone with the right knowledge will be kind enough to help me.
I ripped out this tacky input board, and installed silver plated RCA posts.
The top wire is some sort of muting path as the amp won't turn on with sound unless this wire is soldered to one pf the input wires.
(please ignore the terrible sight of the RCA soldering, it's just because of so many hours of soldering and unsoldering to try and get it working!)
The amp sounds good even with this missing music issue. Both speakers play I should clarify, its just that music is missing from songs.
Thank you for any help!
I took apart a rubbish Power Dynamics amp and put the bare bones parts in a nice small chassis. I have a song by John Foxx of Ultravox which I use for testing. The track Metal Beat from his 1980 album Metamatic.
His lyrics travel from channel to channel back and forth. Please forgive my lack of knowledge. This is my third amp build, and the only one I'm struggling with.
Basically half the lyrics are missing. From 40 seconds on it's very clearly wrong.
I'm hoping from the following photos of the layout someone with the right knowledge will be kind enough to help me.
I ripped out this tacky input board, and installed silver plated RCA posts.
The top wire is some sort of muting path as the amp won't turn on with sound unless this wire is soldered to one pf the input wires.
(please ignore the terrible sight of the RCA soldering, it's just because of so many hours of soldering and unsoldering to try and get it working!)
The amp sounds good even with this missing music issue. Both speakers play I should clarify, its just that music is missing from songs.
Thank you for any help!
Thanks for replying, I think you helped me with my first mosfet build 😊
That's what I'd like to know, the wires are so confusing I've not attempted any projects with a TDA before. The amp was one of these horrible Power Dynamics PDM mixer amps.
Could I hardwire straight to the pins and just bypass what the board is doing for the input paths?
Thank you so much! 😊
Listening to it now and is perfect.
This must have been painfully obvious to you and others with the experience so I'm so grateful for your help. I can finish putting the chassis together next.
Well thank you for doing that! 😊 It's so refreshing to meet a fellow enthusiast who isn't obnoxious or nasty. I learn in leaps and bounds and the passion for our hobby is what drives me to keep experimenting. Next up is a PTP wired LM3886T! Have seen some fantastic designs on the forums.
Did I do the right thing by connecting that top wire to the input? It stopped the muting and I haven't noticed anything bad.
The chassis used is an old Bang & Olufsen BeoLink Passive. These are perfect for gainclone projects as the whole chassis base is the heatsink. If the pre-existing holes had lined up I would have implemented that design. I've just been getting the layout in order and installed some binding posts on one side which I had to insulate with heat tubing. I'm testing it currently on Mission M71's with Wharfedale Diamond 9.1 tweeters and I'm surprised and pleased with the sound. It's silent too! No hum, hiss or ground issues.