How much do I need to spend to get a preamp that sounds better than no preamp?


Hello all.
I'm using an Audible Illusions L1 preamp and I think my system sounds better when I remove it from the signal path. Oppo BD105 directly to SMC Audio DNA1 Gold power amp. I have read that there is level of quality you need to hit before there will be an improvement in sound. I can't seem to find what that level is. Any ideas?
Thanks in advance,
Ben
honashagen
@honashagen 
you should consider any specific recommendation of equipment as anecdotal as it may not sound nearly as impressive in your system. 

Although unlikely, it’s absolutely possible that a $3k tube preamp won’t impress you as much as a $1k solid state preamp. 

Best to stick your toe in the water, buy something returnable and find out what works for you in your system in your room with your music.... all while realizing it may take a few tweaks to get it right. 
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browndt ... what Amperex tube are you using ? I'm using NOS Mullards and like it.. Try Sophia Tube 274B in the power supply.. I think you'll like it better than the Phillips.. I do