FYI, for anybody that’s interested, some of the tweaks/mods I’m doing include replacing all the power rail decoupling resistors with new parts, replacing select 5% carbon film opamp feedback loop resistors with 1% metal film parts, adding just a couple HF bypass caps in the signal path on the EQ board, and replacing and socketing some of the opamps, and in those instances adding a small value cap across the power rails at each opamp as insurance against oscillation, though likely nothing I’m putting in would be unstable enough to oscillate. What I want to underscore here is, lest anybody go thinking they should just start replacing all 5% carbon film resistors with 1% metal film parts, or that changing opamps is “better”, everything I’m doing is supported by extensive analysis and testing, and with intended purpose…none of it is carte blanche. And none of it is wild stuff. The opamps I’m putting in are considered vintage at this point…I simply believe, after a lot of years of doing this sort of thing and listening and testing, they sound better, but without trying to turn the console into something it’s not. I don’t want to sterilize it, I just want it to sound more like itself if that makes sense. And all the resistor stuff is to 1. hopefully achieve an incremental improvement in the noise floor, even though the console is pretty quiet already…but there are a lot of amp stages…! And 2. maybe achieve some incremental improvement in channel-to-channel tracking, and stereo tracking when using a single input/output module as a stereo input module. Again, the opamps being used are not latest/greatest parts…just TI-branded 5532 and OPA2134 parts, in place of NJM2041 and TL072 parts. And there’s nothing wrong with a 2041 or a TL072…they are everywhere in lots of your favorite gear and even in some coveted gear. I just happen to be able to test and make sure different opamps are actually happy in a given circuit electronically, and then listen to identify if I can even hear a difference, and if I do, decide whether or not it’s a good difference or a bad difference. I generally like the sound of circuits that use the 5532, and where that doesn’t work as an upgrade I find the OPA2134 to be a very stable and good performing alternative to the 072 or the 2041. I’m sure plenty of people would call me a fool to go to the trouble of testing, disoldering, installing just to put in what many consider to be obsolete parts rather than the latest and greatest fastest chip. But often times those folks are going for input=output neutrality, and anything toward that goal is good, and anything otherwise is not good. Again, my goal is to just help the console sound more like itself. Changing opamps is no silver bullet, and there are lots of caveats. So I proceed conservatively and with an objective in mind, a pre-conceived answer to the questions “why am I doing the change, what’s the purpose, the desired outcome, and is it worth it?” Sometimes it’s just curiosity. Anyway, that’s what I’m working on, but just here and there, because the console is now almost back together and fully functional and I want to put it to some use and, while I’m at it produce some new videos that go into better detail as to the functions and operations of the console…something of a video manual in case it’s of interest to others, and, just as importantly, to help me when I forget some needed detail about a particular function. Like all the SOLO functions…there are 5 on each input/output module…where does each one tap the signal path? And which ones are in-place and which ones are not? I can’t remember. This will all become better as I use it more, but it would be nice to document a baseline for reference. Anyway, modules 1 & 2 are partially modified, module 9 will soon be fully modified. Then I can just use it for awhile and get used to it, and be able to identify if even the partial treatment is worth it, and if the full treatment brings any worthwhile benefit. I’m reasonably certain the partial treatment is worthwhile…we’ll see about the full treatment. But it will be nice to be able to just play with it and A/B the different versions.