I highly recommend the following:
Watt Hifi - Makati Cinema Square
- I can spend the whole day here with it's numerous choices and wala silang sawa ipa-audition sa iyo lahat. For Amps it carries, Yamaha, NAD, Onkyo, Rotel, Rega, Cambridge Audio, Musical Fidelity, Cayin etc. sobrang dami. For speakers it has PSB, KEF, Paradigm, Monitor Audio, Aurum Cantus, Mission, Sonus Faber, B&W, Atlantic Technology, Wharfedale etc.
MLY Enterprise - Along Kalayaan Avenue, QC
Sobrang maasikaso and will let you audition everything from Monitor Audio, B&W, Acoustic Energy, Polk Audio, JBL, Infinity, Klipsch etc.
AVDI - Shangrila Mall
Highend shop pero ang babait ng mga salesmen. They are even willing for you to home audition their gears
Never had a bad experience with any those shops.