Studio, broadcast, live sound, location
Single-channel; impedance matching, gain, phantom power, phase and low-cut filter switches; NOS Telefunken tubes; nickel alloy transformers
TAB-Funkenwerk | 785-697-2257 | www.tab-funkenwerk.com
- Sound quality
- Authentic classic German vacuum tube design mic preamp
- Versatile source matching
- Orignal Telefunken tubes and transformers
- Cosmetics take a back seat to functionality
One of the greatest mic preamps in history faithfully recreated
Thanks to Oliver Archut, much of the knowledge required to faithfully recreate some of the finest designs of German vintage vacuum tube audio has been preserved for posterity.
At his first job at AEG Telefunken as a young man of 21, Oliver was assigned to work with the scientists responsible for such classics as the M49 microphone and the preamp designed for it, the V72. These were the kind of men instrumental in the WWII design of U-boat SONAR and the guidance systems for the V-2 rocket. At the war’s end, the Allies barred German industry from all military development so many scientists and engineers moved to more peaceful pursuits, such as studio and broadcast audio.
As Oliver was just entering the field some 30 years later, these men were approaching retirement and were sent to run training centers as there was no place for them elsewhere in the company. This was a time when giants such as AEG Telefunken and Siemens were literally throwing out the past, filling dumpsters with thousands of pages of engineering details, metallurgical formulae, schematics and even complete working machinery for the manufacture of transformers, inductors and tubes, as German industry transitioned to miniaturization and solid state. Oliver began an avid vocation of rescuing and collecting whatever he could of the then-obsolete, but now-precious, technology: the essential knowledge that the great German audio alchemists had created for turning materials such as copper, glass and nickel alloy into the sound of gold. Had he not done so, much of it would have been lost forever.
Today, Oliver’s company — TAB-Funkenwerk — is engaged in the manufacture of transformers, inductors, exact replacement parts and complete designs faithful to the vintage originals. The V78M ($1,195) was conceived to be true to the historic V72S, the mic preamp that was a key component of the early Beatles sound that swept the world. The V78M is an authentic piece of superb vacuum tube audio engineering and available at a price well within the reach of the small or mid-level studio.Features
The V78M is a single-channel, 1U racked preamp designed for budget studios interested in a mic preamp of the highest quality. It is sonically identical to the V72S, the studio version of the famous V72, which in its day was the standard preamp for German broadcast. The V72 rolls off at 15 kHz and 40 Hz to meet the requirements of FM broadcast, while the “S,” or studio version, is full range at 20 Hz - 20 kHz. The V78M’s faithfulness to the original V72S requires a lot more than just lip service. The alloys needed for the transformer cores and plate inductors are no longer made, so TAB-Funkenwerk set up its own metallurgy shop where precise proportions of nickel, iron and cobalt are combined according to the original formulae. Original dyes are used to stamp the cores and a hydrogen atmosphere is utilized for proper annealing. The transformers are hand-wound and are identical to those in the historic V72S. The company has amassed a large collection of NOS Berlin and Ulm-made Telefunken tubes. These come standard in the preamp and are shock mounted. (Oliver maintains that modern Eastern European and Chinese-made tubes just don’t cut it.)
The preamp contains over 2.5 pounds of nickel alloy and mu-metal shielding at a raw materials cost in the hundreds of dollars! Resources have obviously been put where they contribute to the quality of sound. The cost cutting essential to meeting the low price point has been accomplished in benign ways such as through the use of a printed circuit board instead of point-to-point wiring and a no-frills silk-screening of the front panel.
Additional features have been added to enhance the preamp’s usefulness and versatility. German broadcast was all about standardization and modularity. The preamps then were all of fixed gain and fixed input impedance so they could be used anywhere in the network. This is not really a benefit in modern studio work where a wide variety of mics and gain structures are encountered.
The V78M includes an input sensitivity rotary switch that varies the load impedance seen by the microphone from 1 kohms to 20 kohms. The switch legend is given in nominal dB to avoid patent infringement with another company that managed to patent the notion of a microphone impedance selector. The precise dB changes will depend on the source impedance of the mic in use. The sensitivity selector allows for a wider range of mics to be matched to the preamp, from low-output ribbon designs to modern high-output transformerless types. A rotary makeup gain switch is also implemented for the purpose of level matching, or for the intentional effect of overdriving the preamp’s final stage. The overall gain range is 22 dB - 60 dB, sufficient for all but the lowest output ribbon types. (TAB-Funkenwerk is planning a future model with a 40:1 input transfer, similar to that in the V77, with 18 dB of additional gain.) Phantom power is onboard with the added nicety of ramping up slowly to avoid damaging sensitive ribbon mics that might be inadvertently plugged in when phantom is turned on. TRS jacks are also available in addition to the usual XLR connections. Finally, there are switches for polarity reverse, 120 Hz high-pass filtering, and 100-ohm ground resistance to minimize hum.In Use
My first trials were of acoustic guitar and voice. A Neumann M 49 tube mic was connected to a transformer splitter box feeding the V78M, an original V72 racked by TAB-Funkenwerk and an Amek Neve 9098. The signal outputs of the three preamps were captured with a Mytek 8X96 converter running at 96 kHz direct into Sequoia for precise final level matching and blind comparisons. The 9098 is a pretty good mid-level preamp — maybe not in the same league as a John Hardy or Millennia Media preamp, but quite decent — and it is roughly the same price as the TAB-Funkenwerk unit. Unfortunately, in this comparison, it was eliminated rather quickly. Its sound seemed artificial and inhibited in comparison with the V72 group. The V78M and the original V72, however, were very close in character. A little HF shelving EQ could make one sound like the other by compensating for the roll-off in the original V72 design. The V78M did, however, sound more energetic and unrestrained then my older V72. This is likely the result of the i
nevitable drift in the component tolerances of the vintage unit over time. The V78 had that instantly recognizable “live in the room” effect/characteristic of a great audio design.
The V78M was then sent to Max Illidge, a talented young producer/engineer and artist previously signed to London Sire and Warner. Max has one of the best sets of ears I’ve encountered lately; he was able to score 100 percent on a blind test to identify different software algorithms for upsampling from 88.2 kHz PCM to DSD — a test that a few of my tonemeister friends did not do as well on. Max was producing a number of rock bands at the time and seemed like an ideal candidate for testing TAB-Funkwerk’s claims of the V78’s versatility. The initial report came in regarding a classic set up: an SM57 on snare. Max said it was the first time he could really hear all the aspects of the drum – the snap, the ring, the shell and depth — and he did not need to EQ the snare in the mix. “All the frequencies and transients cut though the mix,” he commented. “The highs and lows were all there.”He described the sound on vocals with a U 47 as “creamy, rich, and not too sibilant with all the vocal tones and enunciations clear as a bell.” Then finally, a few days later, he called with the defining comment, “I can’t live without it.”
Max begrudgingly did return the unit for my use on a series of vocal sessions with Judy Collins and Rufus Wainwright at Sear Sound in Manhattan. Engineers expect their gear to be capable of capturing both the power and nuance of a performance. In this regard, the V78 excelled. The signal chain for the overdubs consisted of a choice Neumann M 49 mic, a Pultec EQP-1A program equalizer, and a Tube Tech CL-1B compressor. This combination has never worked so well for me as it did with the V78M at the front end. The character and emotion of these great and unique voices came though as big as life and sounded absolutely stellar. Summary
The V78M makes a compelling argument for properly implemented, faithful recreations of classic audio designs. An original V72S is exceedingly rare today since only 300 or so were ever produced, and the V78M is a product functionally identical to a V72S as new in the mid-1960s. Clearly, such an endeavor as building a recreation requires the utmost commitment to accuracy on the part of the manufacturer to be successful. You have to admire a tiny company that makes its own nickel alloys, hand-winds transformers, and makes available one of the best sounding preamps on the planet — not to mention an authentic piece of audio history — all at a price that nearly every working engineer can afford. The V78M is fantastic.Review SetUp
M49, U67 and SM57 mics; vintage V72 preamp, Neve 9098 preamp; Pultec EQP-1A equalizer; Tube Tech CL-1B compressor; Lipinski Sound L-707 monitors