Best place to demo small room setup in LA/SD metro

I have a small den off my kitchen that has housed a NAD 3200 integrated amp and KEF 104/2 speakers. We call it our party system, nice warm background music played at moderate volume. After 20 years, want to upgrade to similar neutral sounding system--great natural sound for small room. Can anyone recommend knowledgable dealers who have expertise in this in the LA and San Diego area. Also, any recommendations for optimizing a $20,000 budget. Open to tube versus solid state.