Interesting project Jeff. Can you tell if it sounds like you remembered it or if it's any different?
Does it sound different? Well, it's been two years since i've heard it, and the expensive NOS tubes that were in it have mysteriously gone MIA. I stuck a spare pair of regular Electro Harmonix 6922's that are not matched in it, and all I can say is that it sounds marvelous!
I've never had issue with the sound of that preamp. Before I got the SHA Gold, most preamps lasted around here a year or two, at most. I ran the SHA Gold daily for 16 years before the Pho-Tentiometer broke, and never thought about getting a different preamp. There are some pieces of gear that I regretted getting rid of over the years, but there was never a preamp on that list. (Well, OK, the Apt Holman did have a pretty sweet phono section!) The magic of the Melos SHA Gold was the delicate Pho-Tentiometer, and your devices are the modern heir to that legacy, except that you've figured out how to make them rugged and affordable! When I fired the Melos back up, it was like reuniting with an old friend.
Yes, it does sound like I remember, it sounds wonderful. The tonal balance does not change with volume changes, it simply gets louder or softer. I did notice that you can turn the LDR3X all the way down. Even at minimum, the Melos Pho-Tentiometer would send some signal through. The Melos has an old school warmth to it, but yes, I can tell that the LDR3X is not adding or taking anything away from the gain stage behind it.
I can also tell that when the warranty on my Preamp that recently came back home expires, I would love to have one of your LDR units inside!