Living sounds, did you happen to try On Semi 5534?
I don't hear any difference.I guess if there are, they are buried by the transformer's response and by the mp3 encoding (and by my aging ears).
It's funny. For years I've read and heard many going on at great length about specific versions of opamps and how desirable they are. I hear basically nothing in my vintage vs new 2520's. Or, nothing worth shaking a stick at...Anyway, I concur.
Interesting, keep it coming!I did more tests, this time with the CAPI 2-ACA on the summing bus. What I ended up with was again the TI NE5534 in the summing position, but with the GAR1731 in the booster slot. In the summing position the GAR1731 takes away low end as well as high end but adds a nice beef to the lower mids and a finished quality to the higher mids, but also some grain to the high end. Ultimately I again prefered the 5534 for summing, it's really full, open and neutral. Surprisingly, in the booster the 1731 had better low and high end and a more cohesive overall sound than the 5534, which sounded kind of worn out. Maybe a problem of marginal stability?
I've probably suggested this before, but with a console you can probably set up two channels in parallel and null them from each other to empirically isolate what the difference is. This won't tell you which one is different, but you can probably determine that from some additional comparisons. Or make bench measurements.JR
http://www.ka-electronics.com/images/pdf/valley_people_trans_amp_applications.pdfHere's a link to the app note over on Wayne's forum. Lots of pearls like this over there. (Look at AN-2 for the VE summer)
Try my gar918BC in the summing position. My favorite. Also Hairball's 990 is great there too!Both DOAs are open and neutral and not quite as thin as the 5534.GARY
Okay, finally got them (from the customs office ), built them, tried them - love them! The gar918BC is now officially my favourite op amp for the summing position (still have to try it for anything else). The difference to the 5534 (BB2521 DOA) is very obvious and I expected a lot less. A veil is lifted from the high- and midrange, a fast low end punch is added (or not taken away). Clarity is all there, unlike all the other DOAs I've tried there's no midrange clutter, hyped top end, added "texture"(=grain), transient restriction etc. noticeable. Very nice!Thank you for this great projec, Gary!Any other recommended uses? I will try preamp and fader buffer next. BTW, I used BD139/BD140 instead of the MJE172/182 in my built.