Dorrough Electronics

Repair, Service, and Parts

Dorrough Electronics repair, service, and parts

Acme Revival is an independent repair network that operates separately from the manufacturers whose devices we service. Our independence enables a repair model that exists beyond manufacturer-controlled strategies, while preserving the ability to work with manufacturers where appropriate.

Woodland Hills, Los Angeles County, California, USA
Manuf. Location
≈ US $1.5M
Annual Revenue (est)
Broadcast Audio Monitoring
End Use Segment

Dorrough Electronics is a small U.S. professional electronics manufacturer best known for precision audio loudness and level-monitoring equipment used in broadcasting, recording studios, film/motion-picture production, and other professional audio environments. The company's signature technology is the Dorrough Loudness Meter, which simultaneously displays average program level and instantaneous peak information, providing engineers with a visual representation of both perceived loudness and transient peaks. Dorrough's product history also includes multiband audio processors, analog and digital loudness meters, video level/monitoring equipment, and related broadcast monitoring hardware. Its level-meter technology became particularly influential in professional broadcasting and recording, with Michael Dorrough receiving industry recognition for his work on multiband processing and the compound level meter. ProMusic

2 Most Seen Failures:

Power Supply Failure

Aging rectifiers, voltage regulators, pass transistors, filter capacitors, and related power-supply components can fail, producing a dead unit, unstable supply rails, excessive drift, overheating, or a burnt smell. DAP 310 and DAP 610 units are particularly associated with power-supply restoration work.

Failed Tantalum Capacitors

Older Dorrough processors can develop shorted or physically ruptured tantalum capacitors on their internal supply rails. These failures may pull down a voltage rail, prevent individual processing cards from operating, or cause complete loss of operation.

LED Display Segment Failure

Individual LEDs or portions of the characteristic Dorrough bargraph display can become dim, intermittent, or completely inoperative with age. Faults may originate in the LEDs themselves or in the associated dot/bar driver and display circuitry.

Meter Backlight Failure

Incandescent scale-illumination lamps used in models such as the 280-D commonly burn out after extended service. The meter may continue measuring correctly while its scale becomes partially or completely unilluminated.

Output Amplifier Failure

Transistors, op-amps, or associated components in the output amplifier can fail and cause missing output, severe distortion, abnormal level, or loss of one signal path. Some failures can cascade through multiple devices in the output stage.

Output Choke Failure

Inductors/chokes in the line-output amplifier can fail with age or electrical stress. This can result in impaired or missing audio output even when the processing and metering sections remain operational.

FET Processing Stage Failure

The FETs used in DAP 310 processing cards can deteriorate, fail, or be replaced with unsuitable substitutes, causing incorrect compression, nonlinear operation, distortion, or poor channel tracking. Correct replacement devices are increasingly difficult to source and normally require realignment.

Adjustment Potentiometer Failure

Internal calibration and adjustment potentiometers can become oxidized, intermittent, or unstable after decades of service. Symptoms include drifting calibration, inconsistent processing levels, erratic meter readings, and inability to maintain proper alignment.

Switch and Control Contact Failure

Mechanical switches and related controls can develop oxidized or worn contacts, resulting in intermittent modes, unreliable functions, or channels that appear to cut in and out. Older DAP processors may require replacement of multiple switches during a comprehensive restoration.

1 Acme Revival offers repair, service, and part rebuild opportunities for most Dorrough Electronics devices.

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  1. 1 Repairs are performed on a best-effort basis. Acme Revival utilizes a network of sophisticated technicians and engineers with diverse service offerings; despite this, factors that influence the repair outcome may ultimately prove unsuccessful. Acme Revival makes no claim that it can, guarantee a repair before your device is sent in for diagnostic evaluation; even then, repair and diagnostic work are not mutually exclusive. Despite well-intentioned quoting, repairs may still prove unsuccessful.
  2. 2 Per information known, researched and collected by Acme Revival and its systems at time of page publishing (September 25, 2026).
  3. *Information regarding this manufacturer/brand/organization is estimated with information collected and known to Acme Revival. This information is intended to provide insights into the spotlight entity, however may not be accurate— information is strictly of estimate nature only.
  4. **The model list shown here may not be an all-inclusive list of the EcoFlow product range. Model list has been derived per information known, researched and collected by Acme Revival and its systems for the US market.