The Tandberg TCD 3034 is a stereo cassette deck introduced in 1981 as part of Tandberg’s Series 3000 range of separate hi-fi components. Designed during the rapid development of high-coercivity and metal cassette tape formulations, the Tandberg TCD 3034 combined the company’s DYNEQ® dynamic recording equalisation system and ACTILINEAR® recording circuitry with a Multicore Senalloy record/playback head. Together, these systems were intended to address the increased recording and bias currents required by metal tape while reducing intermodulation distortion and maintaining linear recording performance at high frequencies.
The arrival of metal tape presented cassette deck designers with significant technical challenges, particularly when using a combined record/playback head. Metal formulations required much stronger recording and bias currents, increasing the possibility of saturating the recording head before the tape itself reached saturation. Rather than abandoning the combined-head arrangement, Tandberg developed several complementary technologies for the Tandberg TCD 3034 to accommodate these demands.
Central to the design was Tandberg’s DYNEQ® dynamic recording equalisation system. Conventional recording amplifiers employed progressively increasing gain at high frequencies to provide the necessary recording equalisation. Although appropriate at normal recording levels, this rising high-frequency gain could become problematic during loud passages containing substantial high-frequency energy, potentially overloading the tape and increasing intermodulation distortion.
DYNEQ® approached the problem dynamically. Instead of maintaining a fixed amount of high-frequency gain, its self-regulating amplifier adjusted high-frequency gain according to the signal level at its input. This allowed the Tandberg TCD 3034 to reduce the effect of high-frequency energy peaks during demanding programme material while retaining the equalisation required under normal recording conditions. Tandberg developed the system specifically to reduce intermodulation distortion and improve recording performance with complex, high-level high-frequency signals.
Working alongside DYNEQ® was Tandberg’s ACTILINEAR® recording system. Developed in response to the greater demands imposed by high-coercivity tapes, ACTILINEAR® used active semiconductor circuitry within the recording amplifier. Tandberg stated that the design reduced intermodulation and interference between the recording signal and oscillator while providing a 15 dB overload margin.
That additional overload capacity was particularly important when recording onto metal tape. The ACTILINEAR® system was designed to accommodate the higher recording requirements of these formulations while providing more linear recording performance, particularly at high frequencies.
The Tandberg TCD 3034 also incorporated a diamond-cut Multicore Senalloy record/playback head. Ordinary recording heads could reach magnetic saturation under the stronger recording and bias currents required for metal tape, producing excessive harmonic distortion before the tape itself was saturated. Tandberg selected Senalloy for its substantially higher saturation limit, allowing the head to operate with the greater currents required for metal tape. The Senalloy cores were also intended to provide significantly increased head life.
The Tandberg TCD 3034 operated at the standard cassette tape speed of 4.76 cm/s and specified a frequency response of 20 Hz to 20 kHz within ±3 dB. With metal tape, its signal-to-noise ratio was specified at 66 dB using the IEC A-curve and 58 dB using IEC Linear RMS measurement. Record/playback speed variations were specified at 0.12% weighted RMS, while total harmonic distortion from tape at a 0 dB recording level was less than 2%.
Connectivity was straightforward, with left and right inputs rated at 80 mV into 15 kohms and left and right outputs providing 1.0 V from a 100 ohm source impedance. A headphone output was also provided, rated at 1.5 V into 8 ohms.
Tandberg also offered several optional accessories for integrating the Tandberg TCD 3034 into different installations. These included side walls, rack handles, a dust cover for the cassette compartment and a professional mounting kit for installation in a 19-inch IES/DIN standard rack.
Features
- DYNEQ® dynamic recording equalisation system
- ACTILINEAR® recording system
- Diamond-cut Multicore Senalloy record/playback head
- Designed for high-coercivity and metal cassette tapes
- Self-regulating high-frequency recording equalisation
- Reduced intermodulation in the recording system
- Reduced interference between the recording signal and oscillator
- 15 dB recording-amplifier overload margin
- More linear recording performance at high frequencies
- Optional side walls, rack handles, cassette compartment dust cover and professional rack mounting kit