I use the CODA 07x preamp with the LSA Voyager 350 GAN amp. It works great sonically. Though the 07x has some operational gremlins and design choices that annoy me. The sound is mostly a winner though. A little bit of whisper quiet hiss also bugs me.
I have also tried the Topping pre90 preamp with the Voyager, CODA #8, and Benchmark AHB2 amps. On the LSA Voyager the volume on the preamp had almost 0 useable steps. On the CODA #8 it sounded flat, likely impendence mismatch. On the AHB2 it sounds great.
The preamp I sold to replace it with the cheaper Topping pre90 was the Benchmark HPA4 (or LA4). In retrospect I wish I did not sell it because I think it would have worked with all 3 amps. I am going to bring it back in the house to see how it works with the Voyager and CODA #8. I am thinking of ditching the Topping pre90 and moving the Coda 07x with my AHB2 mono amps on a second system, which is an awesome pairing.
I am thinking of getting the Benchmark LA4 preamp with the Voyager or CODA #8 (not sure which stays) since I use this system the most and do not want to get annoyed so much. Benchmark has the 30 day home trial which I will use.
The CODA 07x has some warmth to it and although the Voyager is also a little warm it is not a bad combo. The Topping pre90 and Benchmark HPA4/LA4 do not add much sonically. You will hear your sources and amps.