I hear a difference. It's subtle. There are more mids in the EZ1073 version, and more aggressive low end. Not more low end itself, just a sense of aggressiveness in it. It sounds alive and a little less glued. The bounce sounds glued and more cohesive. Etc. It's subtle but there are differences...
I'm not sure what you're complaining about really. If you want a specific color or affected sound -- by definition something that would be something that alters the original audio -- then you are looking at a processor by definition, not a clean pre and line amp. I'm sure the Neve co. were trying to make their designs and products as clean and transparent as possible at the time, and not a processor.
I've worked on Neve boards -- they all sound different. Even among the same models. Who knows why. Beyond all the talk of caps and transformers and terminations… we won't ever know 100%. It's a little art, besides the understood science. Rupert has talked a lot about using ears and not graphs and test gear. In that sense I think your search for sweeps is not going to answer your apparent anguish.
EVERYTHING changes or effects or plays a minor role in audio, even wire, more or less depending on context. I think to settle this discussion you need to sit down with an AMS or original Neve and your EZ1073 and run tests with A/B comparisons. Closely inspect terminations, not just output transformer terminations but everything on the secondary of all THREE transformers. Look at everything and compare every component. Listen. Test with your ears and do some blind listening tests. You may be surprised what you find out.
I haven't build my EZ1073 yet, but if it sounds like yours I won't be complaining. Really. It works. It's quiet, it does its job. If you want a processor to color your sound then you may want to deliberately build it differently next time, deliberately mess with the circuit. Just my 2 cents, please don't get angry or aggressive.
