I recently got a Quad 306 off eBay replace my NAD c320bee (after adding a MiniDSP and a Yamaha streamer/preamp into my setup, only the NAD's power section was being used anyway).
Visually it looks fine inside, no issues with the caps, but it's probably still pushing 25 years old so I was thinking about a service/overhaul.
Quad would be the obvious place to send it, but from reading various threads on there, they only change the binding posts as standard, and anything else is only replaced if it's outside of spec.
Then there's Fidele and Redhill, who offer service and upgrade packages. Their services seem to be fairly well regarded across various forums.
I live fairly close to Fidele so could drop my amp there - their 'stage one' service and upgrade is:
Some people seem to think the amps could benefit from a bit of modernising, whereas others say the only thing you should change be the caps otherwise you start drifting away from the Quad sound.Replace all electrolytic capacitors with Nichicon Audio grade capacitors
Replace Op Amp with selected low offset version of same type.
Upgrade power supply to the Op Amps
Full bench test
Replace binding posts
Adjust input sensitivity to match your pre-amplifier if required
Has anyone done the upgrades with Fidele or Redhill, and would you consider them to improve the sound quality? Or is it better to keep the amp as 'Quad' intended?