DLA-2A: Leveling Amplifier
A Studio Legend at Your Feet
The Doc Lloyd DLA-2A Leveling Amplifier is a meticulous recreation of an iconic studio compressor, now directly compatible with guitar and bass input signals. Less than 25% the size and cost of the original with 100% authentic tone. It took multiple years of dedication to make this ambitious goal a reality, but finally it is here.
The design includes Lundahl input/output transformers, 12AX7/12BH7 tubes, and a Kenetek T4B optical attenuator module. These components are expensive, but absolutely necessary to replicate this classic compressor's unsurpassed audio qualities. Two sidechain tubes are replaced with high voltage solid-state circuitry to significantly reduce size while leaving the original audio path fully intact. The line audio audio path is an exact match of the original schematic with a custom 275VDC low-noise internal power supply providing high voltage to the audio circuitry from a standard 12VDC input. This machine is the real deal.
Typical studio compressors require line level signals from low impedance sources. The DLA-2A has the standard transformer balanced line input as well as a high impedance input with a balanced gain stage, providing direct compatibility with guitar and bass.
The compressed output signal is passed to a transformer balanced line output that can be connected to a mixing console or headphones as well as an instrument level output that can be connected to a pedalboard or amplifier.
DC power is applied to the tube heater filaments and does not generate 60 Hz hum, resulting in lower noise than the classic reference design.
COMPONENTS
- Lundahl 1922 Input Transformer
- Lundahl 5402 Output Transformer
- Kenetek T4B Classic Optical Attenuator Module
- Tung-Sol 12AX7 Vacuum Tube
- JJ 12BH7-A Vacuum Tube
- Calibrated VU Meter with Backlight
- Vishay Beyschlag Thin Film Professional Resistors
- Non-piezoelectric Class 1 Ceramic and Film Capacitors
- Daka-Ware Bakelite Knobs
ACCESSORIES
- Power Adapter (100-240VAC Input, 12VDC 1.5A Output)
- Input and Output XLR Adapters
- Inline Power Switch
CIRCUIT BLOCK DIAGRAM