Want to upgrade my Adcom GFP 565 preamplifier


I want to upgrade to a better preamp that will not cost over $1200, used. I like my current system but can't help but feeling the GFP is the limiting factor, especially in the high's. Any suggestions for a solid state preamp?

System:
JMLab 806s
2 NHT 10 Passive subs
B&K 202+, High
Adcom 5500. Low
Marchand XM9 crossover
Arcam CD72
JVC 1100
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Here's another thought - PrimaLuna ProLogue three preamp - Smooth warm tube sound, but not syrupy. Also, the tubes are auto-biasing so you don't have to be a multimeter jocky to get it sounding right. Look for one used in your price range.

Or, Modwright SWL 9.0SE

In the solid state world, look at a used Classe, Nam NAC 112, Primare Pre30, or a budget fly in the ointment, the new NAD C-165BEE, which is really quite good.
Thank you all for all the comments. You have given me some things to think about for sure.
The Adcom 750 is a Stereophile Class A recommended component but I personally did not care for it. How much are you selling your 565 preamp for?