March 8, 2014 3 Comments
Well, without time to finish new projects, it’s time to (once again) go digging in the “back catalogue” instead :D
Here is my first DIY multichannel amplifier. This is based on three Tripath boards from Sure Electronics that were “flavour of the month” some years ago. The boards are based on the TK2050 chipset with the output drivers in bridge mode (so up to around 100W output per channel according to the specs). The boards are stock except that I removed the clamping diodes on the input (which protects the ICs from excessive input voltages) and replaced the (small and horrible) ceramic input caps with (slightly better) Nichicon Muse ES bipolar electrolytics. The boards shown here are the first version that was passively cooled, all future versions I have seen are cooled by small fans. The heat sinks get fairly hot (around 50-55C) when the boards are running.
The PSU is a Mean Well USP-225-24. This is a little under-powered for five/six channels if driven at high levels, but I have a small room and even driving the relatively difficult 4 ohm Elac speakers I never had any issues with clipping. I actually have a spare USP-350 PSU that I have planned to put in instead for a bit more headroom. However, since I don’t use the amp at the moment, for now that is just one more point on a very long to-do list :D
I was originally not going to show this until after it’s been rebuilt with the more powerful PSU, but as I am not getting to that anytime soon here are some pictures anyway :)