Telefunken TDA-1 Active Mono DI
The Telefunken TDA-1 Active Mono DI is a high-performance direct input box designed for professional studio and live applications where clarity, headroom, and low noise are essential. Built around a custom-designed circuit and housed in a rugged steel chassis, the TDA-1 delivers the renowned Telefunken sound with the added benefits of active circuitry.
Unlike passive DI boxes, the TDA-1 features an active Class A FET amplifier that provides a clean, linear signal path with minimal distortion and high headroom. This makes it ideal for instruments with lower output levels such as passive electric guitars and basses, as well as vintage keyboards and acoustic instruments with pickups. The circuit is powered via standard 48V phantom power, making it easy to integrate with mixers, audio interfaces, or preamps.
At the core of the TDA-1 is a custom-wound OEP/Carnhill transformer that imparts rich harmonic content and analog depth. This transformer, combined with the FET-based circuit, results in a signal that is both transparent and musical, preserving every nuance of your performance while subtly enhancing warmth and definition.
The unit is built to withstand the demands of both the studio and the stage. Premium Neutrik connectors ensure long-term reliability, while the black powder-coated steel housing offers superior durability. A ground lift switch is included to eliminate hum and buzz caused by ground loops, and the intuitive layout makes it easy to set up quickly in any signal chain.
Key Features:
- Active Class A FET DI with custom Carnhill transformer
- Wide dynamic range and ultra-low noise floor
- Ideal for passive instruments and line-level sources
- Requires 48V phantom power
- Ground lift switch to resolve grounding issues
- High-quality Neutrik XLR and 1/4” connectors
- Rugged steel chassis with black powder-coated finish
- Hand-assembled in the USA
Ideal Applications:
- Passive electric guitars and basses
- Vintage keyboards and electric pianos
- Acoustic instruments with pickups
- Line-level signals from synths, samplers, and audio interfaces
- Studio recording and live sound reinforcement
Technical Specifications:
- Type: Active Mono Direct Injection (DI) Box
- Circuitry: Class A FET amplifier with custom Carnhill transformer
- Power Requirement: 48V phantom power
- Frequency Response: 20 Hz – 20 kHz, ±1 dB
- Input Impedance: 1 MΩ (typical)
- Output Impedance: 150 Ω (typical)
- Maximum Input Level: +22 dBu
- Input: 1x 1/4” TS jack
- Thru: 1x 1/4” TS jack (parallel)
- Output: 1x balanced XLR male
- Ground Lift: Yes
- Chassis: Steel with black powder coat
- Dimensions: 4.88” x 3.1” x 1.9” (124mm x 79mm x 48mm)
- Weight: 1.1 lbs (0.5 kg)
- Manufactured in: USA
With its powerful active circuitry and analog transformer warmth, the Telefunken TDA-1 Active Mono DI delivers best-in-class performance for musicians and engineers seeking pristine signal quality and professional-grade reliability. Whether you’re recording in a high-end studio or performing on stage, the TDA-1 ensures your instrument’s tone is captured accurately and musically.
