The 47 labs IC-based amplifiers launched an entire fleet of hobbyists and commercial endeavors to build similar amplifiers, mostly based on the LM1875, LM3875 and LM3886 devices. Thousands were made, and thousands of people had (and still do) a wonderful time building and listening to these amplifiers.
Gaincard, Gainclone, Chipamp, call them what you will, this hobby is forever in their debt and I wholeheartedly feel that everybody should build one. Fantastic devices.
As for sound, in my opinion they all have a distinct character (which is very nice) and if properly built, no hum, good PSU, etc… will deliver that beautiful character easily to your music. So yes, I suspect the above amplifiers that you are asking about sound very similar.
Gaincard, Gainclone, Chipamp, call them what you will, this hobby is forever in their debt and I wholeheartedly feel that everybody should build one. Fantastic devices.
As for sound, in my opinion they all have a distinct character (which is very nice) and if properly built, no hum, good PSU, etc… will deliver that beautiful character easily to your music. So yes, I suspect the above amplifiers that you are asking about sound very similar.