ARP Avatar

A groundbreaking pitch-to-audio device designed by ARP.

Pete Townshend's ARP Avatar

When it first arrived, the Avatar was not in working order.

Here is a look inside from that first inspection, where it looked like a voltage regulator had blown. The full restoration is below.

ARP Avatar Service ManualDownload

From the workbench

Restoration videos

Pete’s ARP Avatar, serial number 0001, came to the bench not working, with what looked like a blown voltage regulator. After a thorough clean, the seven-part restoration works through the whole instrument: Part 3 repairs a broken E gate, Part 4 traces the power supply faults and Part 5 rebuilds the PSU. Part 6 is a deep service that also fixes oscillator 1’s square wave, and Part 7 brings it all together. It finishes with the first jam after restoration, plus new replacement slider caps.

ARP Avatar s/n 0001 Repair Part 1

Chapters 14

  1. Intro – meet the ARP Avatar
  2. Missing knobs & the guitar input
  3. Outputs, CV & gate
  4. Opening it up
  5. The boards & bus panel
  6. A short on the positive rail
  7. Running from bench supplies
  8. First sounds
  9. Cleaning the pots
  10. Oscillator 1 test
  11. Oscillator 2 & the filter
  12. High-pass filter & VCA
  13. ADSR problems
  14. Plans for the power supply
Part 2

Chapters 9

  1. Intro – the GR-500 guitar
  2. Powering up with the guitar
  3. Low E not triggering
  4. Swapping the faulty pickup
  5. Cleaning the contacts
  6. String test
  7. The pots come back to life
  8. Serial number 0001!
  9. Plan: remaking the PSU PCB
Part 3 – Repairing the Broken E Gate

Chapters 8

  1. Intro – the burnt power supply
  2. Monitoring current draw
  3. The E gate detection circuit
  4. Replacing the faulty parts
  5. Swapping the bypass tantalums
  6. Power-on test
  7. The E string works!
  8. Remaining issues & next steps
Part 4 – The PSU

Chapters 9

  1. Intro – burnt tantalum & resistor
  2. Cleaning the factory flux
  3. Why the fuse didn’t blow
  4. Isolating the damaged area
  5. Power-on test
  6. Originally 110V or 240V?
  7. Why the PCB needs remaking
  8. Recreating the PCB from the service manual
  9. KiCad & ordering from PCBWay
Part 5 – PSU Rebuild

Chapters 7

  1. Intro – the new PSU PCB arrives
  2. Checking the fit
  3. Transplanting the parts
  4. The finished board
  5. Moment of truth
  6. Adjusting the voltage rails
  7. Next: recapping the Avatar
Part 6 – Deep Service & OSC 1 Square Wave Fix

Chapters 11

  1. Intro – faders & the quiet square wave
  2. Replacing the tantalums
  3. Three boards done
  4. Removing the bus board
  5. Getting to the filter board
  6. The worn fader
  7. Replacing the faders
  8. Tracing the square wave fault
  9. Faulty CA3086 found
  10. New chips fitted – all working
  11. Plans for the original parts
Part 7 – The Finale

Chapters 6

  1. Reassembly
  2. New slider caps
  3. Fitting the new power supply
  4. Moment of truth
  5. The PSU PCB on PCBWay
  6. Final jam
First jam after restoration
Replacement slider caps
Avatar restoration playlist on YouTube

More from the collection in the London College of Music playlist on the Really Nice Audio channel.