VÜN Audio Tech VÜN audio tech V72

V72 Microphone Preamplifier

The V72, already produced by countless German companies within the SIEMENS universe (Maihak, Telefunken, AEG, etc.), has gone down in history as one of the finest microphone preamplifiers ever built. Even today, its unmistakable sound can be recognized by listening to the famous EMI recordings; throughout the 1950s and 1960s, many of these studios were equipped with this famous preamplifier. The records that brought the Beatles fame and notoriety were recorded using the V72 (and that's history).

We at VÜN AUDIO TECH, having refurbished several of them over the years, realized how far this little German gem fell short of the parameters commonly defined as vintage sound. This definition, in fact, is associated with a very colorful and lacking dynamic sound. Undoubtedly, this definition is true for many similar products, but in the case of the V72, things are different: we are faced with a tube microphone preamplifier with exceptional linearity and silence. With a few small modifications to the power supply stage and careful engineering, we managed to obtain a frequency response of 20 Hz to 20 kHz +/- 0 dB, with a signal-to-noise ratio of -104 dB @ 1V input. No current reissue has achieved these specifications. Any designer knows how difficult it is to achieve these performances using "only" two tubes in a common single-ended configuration.

The changes introduced in our interpretation of the V72 concern an accurate regulation of the anode and filament voltage, a careful development of the Phanton power supply, as well as the use of a variable ratio microphone input transformer to better adapt to different gain needs. We have also added an additional HI-Z input to allow the preamplification of peck up based and digital instruments.

The gain stage was entrusted to two military-type Soviet 6Ж32П (6J32P-IV) pentodes with extraordinary acoustic and electrical characteristics to replace the unobtainable EF804s used in the original project. After countless comparisons between the different types of pentodes, as far as we are concerned, we find that the 6Ж32П is actually the exact replacement of the EF804.

A clever mechanical design that isolates the power transformer from the rest of the sensitive components, ensuring top performance, makes the VÜN AUDIO TECH V72 an indispensable tool for all engineers who wish to capture the magic of beautiful tube sound through recording without sacrificing any quality.

When considering the choice of materials—from the all-aluminum enclosure for greater isolation, to the input and output transformers (SOWTER), to the vacuum tubes, and the highest-quality polypropylene capacitors—we have no hesitation in stating that the VÜN AUDIO TECH V72 is, in terms of finish and construction, the finest tube preamplifier on the market.

Microphone input impedance : variable from 12 KOhm to 100 KOhm

HI-Z input impedance : 1 MOhm

Output impedance : ≤ 300 Ohm

Signal to noise RATIO : -106 dB (peak unwaighted) @ 1 Volt input

Band pass : 20 Hz – 20 KHz

                  +/- 0.3 dB RATIO 1:3

                  +/- 0.1 dB RATIO 1:5

                  +/- 0.8 dB RATIO 1:9 VINTAGE CHARACTER

Distortion : 0.07 % @ +4 dBu

Dimension : 90 x 130 x 300 cm 

Operating voltage : 230 V (45 Watt)