Originally Posted by robmil
Has anybody here listened
to various DIY discrete opamps?
I have made a clone JE990 and it is very good but wondered if there is anything A LOT better out there - soundwise?
I looked at the various Sam Groner opamps as well as the line-up modified 918 as well as the plenty on the net.
I suppose I am asking what shouldn't I bother with as a DIY experiment
OK, you have to compare apples to apples. First, the JE990 and their ilk have output current capability of some 250mA. As far as I know, there isn't a normal chip opamp that can do that on it's own. You have to add something like a BUF634 buffer inside the feedback loop to achieve that kind of output drive.
So, if you compared, say, an LME49710 + BUF634 (@ +/-15vdc supply) to a JE990 (@ +/-25vdc supply), I think it would be unlikely that you could hear the difference (unless you want to drive something to 35 volts!). They would also probably measure about the same, given the same gain, etc. The difference is that the chips are probably more consistent than the discrete, and far cheaper too.
Still, I have been fooling around with a hybrid discrete opamp, where the front end is discrete and the diamond buffer is provided by a BUF634 (or equivalent). I don't see the sense in having two diamond buffers, one in the LME49710 and one in the BUF634.
Last edited by dirkwright; 13th February 2014 at 03:04 PM.