Our Quad 22 repair/service/socket upgrade normally includes: • Fault, diagnosis and rectification. • Replacement of all cathode bypass electrolytics. •  Replacement of all signal coupling capacitors with high quality polypropylene types. • The triple smoothing capacitor will either be left in situ and electrically reformed ( only if it is in good physical condition and reading a low ESR and correct values), or it will be replaced by 3 individual capacitors. • All out of tolerance resistors are replaced with high stability, low noise, high tolerance metal film types. •  The push button switch contacts and rotary controls are cleaned to remove noise inducing dust and dirt. • The four valves are tested on an AVO valve tester and the individual mutual conductance and anode current performance is labelled on each. If your valves are faulty, we can add them at cost if required. •  The full set of phono connectors are stripped out and fitted with gold plated connectors on hand assembled PCB strips. • We remove the 2 pin mains connector and fit a conformal earthed  IEC connector. • Finally after carefully checking the bias, and dc operating points, we carrying out a full performance check (frequency response/distortion), and a listening test followed by a 24 hour soak test and Portable Appliance safety Test (PAT).  NOTE 1: Our service price does not include replacement concentric volume/balance control, faulty knobs or push button switches. These items are no longer available except as spare parts taken from another Quad 22. If you think your switch bank or pots are faulty but the rest of your Q22 looks clean, you may be able to acquire another Quad 22 for spare parts.  In which case if you send both, we may be able to make one good one out of the pair. If these controls are beyond use we will inform you before proceeding with the service. NOTE 2: It is highly recommended that you send your Quad 22 and Quad IIs together if you are using this combination. We can then electrically test them and make good any issues found.  The image above shows a Quad 22 fully serviced with phono and mains socket upgrade.