TDA-1 Mono Active Direct Box

The single-channel active TDA-1 phantom powered direct boxes utilize top quality components in a modern take on classic circuitry to deliver a full, rich sound that both complements and retains the natural tone and character of the instrument. By pairing discrete Class-A FET circuitry with a high quality, European-made transformer and a rugged metal enclosure, the TDA DI’s provide exemplary sound quality and reliable performance. The circuit boasts a frequency response of ± 2dB from 20 Hz to 70 kHz with extremely low distortion and self-noise, and each individual unit is manually tuned for the lowest possible distortion figure in TELEFUNKEN’s US facility. This careful attention to detail and high-quality component choices result in a harmonically rich low end and a detailed, open high-end. On the TDA-2, each channel features its own independent -15dB pad, ground lift, and +48V phantom power LED indicator. Every TDA unit is assembled, tuned and tested in Connecticut, USA.

Features

• Custom-wound OEP/Carnhill transformer, made in the UK• Phantom powered class-A discrete FET circuitry• Switchable -15 dB pad and ground lift• All metal construction• Recessed switches and connectors• 100% through-hole components• Assembled, tuned and tested in the USA

For audio professionals and enthusiasts seeking pristine sound quality and reliable signal integrity, the Telefunken TDA-1 Mono Active Direct Box offers an essential solution. When recording or performing live, maintaining a clean, noise-free audio signal is paramount, especially when connecting instruments or line-level sources to mixing consoles or audio interfaces. The TDA-1 ensures this by actively balancing and isolating signals, minimizing interference and preserving the original tonal characteristics of your audio source.

The core advantage of the Telefunken TDA-1 lies in its active design combined with a custom-wound OEP/Carnhill transformer. Unlike passive direct boxes that rely solely on transformers, the active circuitry provides a high input impedance of over 30 kΩ, ensuring minimal signal loss or loading from your instrument or audio source. This means your sound remains transparent and untouched, capturing every nuance with precision. The custom OEP/Carnhill transformer further enhances signal fidelity by providing excellent common-mode rejection and low distortion, which translates to a cleaner, warmer, and more natural tone in your recordings or live sound.

Frequency response is a critical factor in preserving audio quality, and the TDA-1 excels with a broad range spanning 20 Hz to 50 kHz with ±1 dB accuracy. This extended frequency range ensures that both sub-bass lows and ultra-high harmonics are faithfully transmitted, supporting the full spectrum of your instrument or line-level device. Whether you are recording a deep bass guitar or a shimmering acoustic guitar, the TDA-1 captures all the detail without coloration or loss.

Connectivity options on the TDA-1 meet professional studio and stage requirements. It features a 1/4″ jack input for easy connection to guitars, keyboards, or other line-level devices, alongside a balanced XLR output to interface seamlessly with mixing consoles and recording equipment. Additionally, the 1/4″ thru output allows you to simultaneously send the signal to an amplifier or monitor, offering flexibility during live performances or studio sessions. The output impedance is kept under 250 Ω, which ensures compatibility with most professional audio equipment without introducing noise or signal degradation.

Handling high sound pressure levels is crucial for an active direct box, and the TDA-1 comfortably manages up to +3.5 dBV without a pad and up to +18 dBV when the pad is engaged. This capability allows you to connect sources with varying output levels without fear of distortion or clipping, preserving clarity even at higher volumes. The device is powered by standard +48 V phantom power, simplifying setup by eliminating the need for batteries or external power supplies.

Compact yet robust, the Telefunken TDA-1 measures 100 mm in length, 100 mm in width, and 50 mm in height, weighing only 465 grams. This makes it portable and easy to integrate into any studio rack or live rig without taking up valuable space. Its durable construction ensures reliable operation even under the demands of frequent transport and stage use.

In practical terms, the TDA-1 excels in a variety of scenarios—whether you are a recording engineer capturing the pure tone of a bass guitar, a live sound technician needing a reliable DI box for stage instruments, or a musician aiming to preserve your instrument’s sonic character when connecting directly to a mixer. By delivering clean, balanced signals with minimal noise and distortion, this direct box significantly improves the quality of your audio chain.

The Telefunken TDA-1 Mono Active Direct Box is a professional-grade tool designed to meet the highest standards of audio fidelity and reliability. Its combination of active circuitry, custom transformer design, wide frequency response, and flexible connectivity ensures that your sound is captured and transmitted with uncompromising clarity. Investing in the TDA-1 means investing in the integrity of your audio signal—delivering confidence whether in the studio or on stage. With a price of ₹33,890, it represents a valuable addition to any serious audio setup, promising long-term performance and sonic excellence.