brooks berdan in monrovia is superb. i purchaseed my preamp from him.
in san diego, you may want to check out stereo design. [bought my speakers there] they have several listening rooms. with a $20k budget, you will have a variety of excellent options, perhaps many that will get you closer to "neutral" than NAD, which is excellent in it's price range, but at 20K, you have the opportunity to purchase above where NAD shines brightest. i think much has changed in 20 years especially in terms of quality choices. i suggest going to a variety of showrooms with your favorite cd's, and start by listening, taking notes about what impresses you and what does not.note model numbers, not only brand names. keep in mind that system synergy is key. poor sounding speakers in one system may be wonderful in another, and since you are starting fresh, matched amp/preamp may be a good way to go, perhaps even an integrated component may offer you more $s for other aspects of the system, such as better quality cables and ICs, which can make a huge difference in obtaining the highest quality from specific componenets . maybe a power conditioner is needed in the budget too? if you decide that the system you purchase is going to stay put for 10+ years, as your last one did, then communicate this to the dealers. you need to approach the system as a cohesive whole from the start rather than compromise one part of the system with the intention of upgrading in a year or two, as many in audiogonland do. [different approaches to suit different goals - short and long term -- and the realities of budgets.] if you do not plan any major upgrades in the next few years, go for a system you will enjoy from the get-go, one that presents excellently all around as it is, not with one weak link. often a system with one component in a league far above the others does not create the best possible system for here and now enjoyment. [my system, for example, is one that will continue to evolve over the next few years. my "turntable system" is far below the other components. i can live with that presently because vinyl is not a key focus currently. if i required the system to be complete and more even-sounded at this time, i might have purchased different speakers and placed more money into the turntable section.]
cheers.
ps. listen to a wide variety first. initially, if you start your search with the thought to re-educate your EARS as much as your intelligence about the current audio choices, you will be in a much stronger position in a few months [yes, not weeks] to make choices for the long term.