I was listening to my Class A amps and needed a nice Class AB chip amp to compare, and so dusted off my glued-on-a-plank Folsom TDA7297 amp. I upgraded the cheap no-name MKT input caps to Wima 2.2uF 100v MKP's, shored up the connections from the amp to the banana jacks with solder joints, soldered on a PCB mount RCA jack, and soldered on a 5.5mm coaxial barrel jack for a 24v 5A SMPS. Listening to it now on my 10F/RS225 FAST speakers. It's a very nice sounding amp! I think the TDA7297 internal topology is a quasi-complementary output stage, which helps impart it with, I am guessing some nice H2 dominant harmonic profile.
Here are some photos of the revisted amp with some improvements. I put on a fresh TIP42 BJT for the cap Mx. The heatsink there may be a little small, and will be upgraded to a larger one soon. I am using a little fan-cooled GPU cooler fed by a 7812 with a resistor to get the speed way down for silent operation. One way to do this is to run flying leads on the cap Mx BJT and mount it on the GPU cooler heatsink as well - plenty of capacity left as it is not even warm with the fan running. Keeps the amp nice and compact. Amp is absolutely silent with ears pressed to speaker cone.
Running a SMSL Sanskrit 10 DAC from Win10 PC and playing tunes from a playlist on Amazon Prime HD.
Here are some photos of the revisted amp with some improvements. I put on a fresh TIP42 BJT for the cap Mx. The heatsink there may be a little small, and will be upgraded to a larger one soon. I am using a little fan-cooled GPU cooler fed by a 7812 with a resistor to get the speed way down for silent operation. One way to do this is to run flying leads on the cap Mx BJT and mount it on the GPU cooler heatsink as well - plenty of capacity left as it is not even warm with the fan running. Keeps the amp nice and compact. Amp is absolutely silent with ears pressed to speaker cone.
Running a SMSL Sanskrit 10 DAC from Win10 PC and playing tunes from a playlist on Amazon Prime HD.
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Because there may be a small influx of curious people from a YouTube video, there are some boards available. But for more advanced people the new one is available.
hi all,
i bought a set of boards to build two amps a while back and i must accept the fact that i won't ever do this build. i paid $90 shipped; $90 or nearest offer, and they're yours. they're still in the box, never untaped...
thanks,
doug s.
i bought a set of boards to build two amps a while back and i must accept the fact that i won't ever do this build. i paid $90 shipped; $90 or nearest offer, and they're yours. they're still in the box, never untaped...
An externally hosted image should be here but it was not working when we last tested it.
thanks,
doug s.
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