Предусилители — Trafomatic Audio Tara 30A

The Tara 30A from Trafomatic Audio is a line-level valve preamplifier built as two separate chassis, a signal unit and an external power supply. Its name comes from the EML 30A triodes that form the output stage, and the design runs in Class A push-pull with custom output transformers wound by Trafomatic itself. The company lists it alongside the LARA among its line stages, and it is the heavier of the two - the two-box LARA also runs 6N30P valves in Class A but weighs 10 kg and quotes a response of 10 Hz to 67 kHz.

Key specs that matter

The selector handles three XLR inputs and a single RCA input, while two XLR and two RCA outputs per channel can drive a pair of power amplifiers or an amplifier plus a subwoofer at once. Both the XLR and RCA outputs have an impedance of 25 ohms. Total gain is 21 dB with 6N30P driver valves and 25 dB when 6N6P types are fitted instead. Frequency response runs from 5 Hz to 200 kHz at -1 dB, with a noise figure of 98 dB below signal. Each chassis measures 470 x 350 x 120 mm, and the pair together weighs 22 kg.

Engineering and use context

Its valve set consists of two 6N30P double triodes as drivers and four EML 30A output tubes, two per channel in push-pull. A feature Trafomatic calls Dynamic Balance lets the owner trim the operating conditions so that both EML 30A tubes in a channel work identically. The power supply unit uses a low-inductance toroidal transformer made in-house, custom chokes of high inductance and Mundorf MLytic HV capacitors. Mains can be switched between 230 V at 50 Hz and 115 V at 60 Hz, and consumption is 200 VA. Fusing is a 5 x 20 mm glass cartridge rated 3.15 A for 230 V operation or 4 A for 115 V. The front panel carries the input selector and volume control, and a receiver window accepts commands from the supplied remote. Volume should sit at minimum when the unit is switched on. Trafomatic rates the valves at around 10,000 hours and suggests replacing them after 36 months of use.

Pairing

The very low output impedance lets the Tara 30A drive long balanced runs to monoblocks placed near the speakers without trouble. With two outputs of each type per channel, a bi-amp setup using a pair of stereo amplifiers can be wired directly. A solid-state or valve power amplifier with balanced inputs makes the most of the XLR-based signal path, and the gain range suits sources of ordinary line level.

Alternatives

Trafomatic's Evolution Line One is a smaller single-chassis valve line preamplifier using one ECC88 per channel with five line inputs and a subwoofer output.