https://rpaudio.estranky.sk/fotoalbum/mbl-6010-preamplifier/
Fantastic preamplifier. Excellent sound. With LM6171
Fantastic preamplifier. Excellent sound. With LM6171
That's a difficult call to make because different ohmmeters will source different tests currents, and since junctions of transistors, rather than just resistances are involved, voltage drops will vary in a nonlinear fashion with applied test current. That will make for unpredictable and different readings amongst the different meters used to make them.To verify a genuine AD797 what is the approximate resistance that I should measure between pins 1 & 4 and between pins 4 & 5?
Is 1000 Ohms what we are looking for? (That was quoted above for AliExpress sourced parts in #134.)
Here it is by @scott wurcerNot a chance of a fake, there is not one IC op-amp you could rebrand with that pin out.
Great idea, but I've never heard about it....Douglas Self Preamp that you can find right here in DIYA...
Is was an LSK389. I used a similar scheme with the JFETs in this preamp (links will take you to the audioXpress article)Dennis Colin wrote an article in a construction-oriented audio magazine similar to The Audio Amateur, if not that magazine, about a phono stage he designed called the LP-797. It used a very low noise dual JFET with both transistors paralleled (LSK489 or some similar type-number; don't remember exactly) bootstrapped by an AD797 to remove miller effect and to linearize its performance. That stage implemented the HF roll-off of the RIAA curve passively. This drove another AD797 set up as a straight gain stage with a switch to select one of 3 possible gains, and that stage drove another AD797 that implemented the bass boost using feedback. I built one and can say that it is accurate as far as EQ conformance goes (better than 0.5dB everywhere), is dead silent, and it's just not there; you hear just the music, without a trace of the preamp's presence. Highly recommended!