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Brauner VM1: Consequence of an Experience

by Rip Rowan, Editor, ProRec.com, April 1999

Most businesses these days are run with computers, marketing, and money. Even in the world of pro audio. Therefore it’s always refreshing when I find a company which is run by brains, engineering, and passion. Especially in the world of pro audio.

I was introduced to Brauner microphones by Brad Lunde of TransAudio Group. Brad had heard about ProRec at an AES show and wondered if ProRec would be interested in hearing the Brauner microphone. I was a little skeptical. Here at ProRec we’re interested in the cutting edge of recording equipment. My concept of Brauner was that of a company that built new versions of classic microphone designs. So, where’s the story? I decided to audition a Brauner VM1Brauner VM1 microphone, if only to justify my skepticism.

Overview

The VM1 is a large-diaphragm multipattern tube microphone. It has a utilitarian look and feel similar to that of the Groove Tube MD1 microphone, sort of a cylinder with a windscreen. The body of the mic is sturdy and heavy, with an engraved logo and unit number (I got unit 227).

The body of the mic is clean and lacks any switches or controls. It houses a hand-lathed, gold-sputtered diaphragm and the amplifier circuitry. All connections inside the microphone are hand-soldered and no connectors are used in the design of the mic, a key contributor to the mic’s extremely low self-noise which is as low as any tube mic at 13 dBA (IEC 651). Yes, Ma, the capsule is soldered right to the tube’s control grid. The tube is a vintage Telefunken EF 806S tube in a non-feedback class-A amplifier design. The power supply contains the pad switch and the pattern control. The pattern control is continuously variable from omni to figure-8 and everywhere in between. No filtering or bass rolloff is provided, resulting in a straighter signal path and eliminating other sources of noise and phase shift. A useful grounding switch offers "hard" ground, ground lift, and "soft" ground (through a capacitor). A toroidal transformer design provides high voltage power with low noise. A -10 dB pad switch is provided, along with a power light which changes color to indicate that the pad is engaged.

The VM1 shock mount is easy to set up. Two plastic rings tighten around the body of the mic to hold the mic in the shock mount. A quick-locking lever allows the user to easily change the angle of the mic. The six-point elastic suspension combines with the heavy (five-plus pounds) body to virtually eliminate vibration noise. A large, somewhat clumsy windscreen is included. This (optional) windscreen encircles the mic 360 degrees around with a fabric / wire mesh which is acoustically transparent. It does a good job of eliminating wind noise and consonant plosives, however, the mic’s built-in windscreen mesh does such a good job that I felt the optional windscreen unnecessary. It’s a great feature for group / ensemble vocals, where the performers can surround the mic. The mic is capable of great paper performance. Surprisingly for a mic with such a low noise floor, the VM1 offers excellent sensitivity (28mV/Pa). The high S/N level (81 dBA, 1Pa / 1KHz / Cardioid) and a high SPL rating (0.3% THD at 142 dB SPL) make the mic suitable for all kinds of instrumentation from the very quiet to the thunderous. The low noise floor and excellent sensitivity are particularly remarkable in a tube design and can only result from an obsessive attention to design. This is not a mass produced piece of gear. In fact all the manufacturing for the small company is carried out by hand in a small barn in the German countryside. Considerable hand-made craftsmanship goes into each microphone, and you can feel it when you set the mic up. The tight tolerances and solid feel are dead giveaways of a hand-made piece of gear. The sturdy carrying case neatly packages the mic, its shockmount and windscreen, the power supply, and all cables. The mic is as much a piece of art as the music it’s intended to record. All this craftsmanship comes at a price, and with a pricetag of five grand ($4995), you probably won’t be buying these by the dozen. VM1s have quickly established themselves as staples in many major studios. VM1s have been used (with great satisfaction) by engineers like Bruce Swieden and artists like Collective Soul, Mick Fleetwood, Joan Osborne, and Eddie Van Halen, who bought 5 VM1s (!!). In fact the VM1 review unit I received had a storied history – and future. It was fresh from a series of sessions at Todd-AO where Steven Kempster and Trevor Rabin had been using it to record tracks for major motion pictures like Twister, Armageddon, Enemy of the State, and the upcoming Disney release, Tarzan. I was informed that I couldn’t keep it for too long. Don Henley was going to evaluate it for inclusion in his new studio.

Gee, I hope I don’t drop it.

Usage

I used the VM1 in several different recording situations. To begin with I used the mic in my home rig, using the onboard preamps of my Mackie mixer running directly into the 20 bit converters of an Aardvark 20/20 system. Obviously, a Mackie mixer is not the ideal preamp for auditioning the delicate nuances of a high-end microphone. Nevertheless, I have a lot of experience with this mixer in this room and have heard a lot of different microphones through the Mackie preamps, so it’s a good point of reference for me. The first track I recorded with the Brauner was a jazz-feel drum track for a set of loops I’m creating. The drum feel we’re going for here is a mono, single-overhead feel, using only snare, kick, and ride. The Brauner was an excellent choice. I set up the VM1 in onmi mode about three feet over the snare, just over the drummer’s right shoulder in sight of the snare and the beater side of the kick. The first thing I noticed when soloing the microphone was its impressive focus. The wide dynamic range and high headroom of the mic was evident, with a detailed cymbal sound, a full-range snare sound, and a snappy kick. Often, snare drums suffer in this kind of miking arrangement, but the Brauner is so flat, with just a slight amount of smooth high-end rise, that the snare sounded perfect with no EQ needed. The snare had an excellent "snap" and the cymbals were smooth and not ringy, indicating great transient response and good amplifier performance. The kick was punchy and I could distinctly hear the low end going down towards 20 Hz, though the distance miking kept the sound tight and powerful. The result was that each drum was in its proper place in the blend, and the sound coming out of the speakers sounded like the listener was sitting right there with the drummer. The focused sound was easy to place in the mix and had a great feel.

I was really impressed with the sound of the ride cymbal. Few, if any, large-diaphragm tube mics have a high end this clear. The attack was extremely crisp and dynamic without being overemphasized. The un-EQ’ed sound of the ride coming through the Vifa tweeters in my monitoring system was tonally identical to the sound of the cymbal in the room. That’s a real feat for a large diaphragm multipattern tube mic. The inescapable conclusion, which was borne out in further testing, is that this mic has virtually no phase-shift problems. Next I recorded male and female vocals with the VM1. The female vocalist, Martha Schottman, is a Christian artist with a uniquely excellent voice. She has the kind of voice that would sound good recorded with a jambox, so I couldn’t wait to hear her voice through the Brauner. We tried a few different positions and mic patterns. I started with the mic in its onmi mode for the flattest frequency response and slowly dialed it towards a cardioid setting. I was very surprised to discover that the VM1 has only the slightest proximity effect. It was a proximity effect different from any mic I’ve ever heard, shifted about an octave or so up from the more common 150 Hz-ish boom of most cardioid mics. The effect was more of a low-mid or upperbass boost than the beefy sound I’d expected to hear from this big mic. If any sound can be called "warm" it’s the close-miked sound of a voice through the VM1 in cardioid setting. The rise in low-midrange adds a thickness that’s hard to find with EQ or other mics. On Martha’s voice it sounded great, although during mixdown we cut a little ~300 Hz. We probably should have backed off the mic a little. At any rate, the sound of the VM1 as a vocal mic can definitely add warmth to the mix.

And now another word about the treble response of the mic. Now, let’s get one thing perfectly clear — I’m a fan of the sound of the "good" harmonic distortion produced by vintage U47s and C12s, and newer mics like the Rode Classic IIRode Classic Valve. The shiny brightness created by these mics is the trademark sound of many classic recordings. Well, if you like that sound, then you might not like the VM1. The combination of the non-feedback amp design, the lack of bass filters, and the pristine design creates a cleanliness that really sounds a lot more like the treble-end of a small diaphragm mic than a large diaphragm mic. There was no audible treble harmonics produced by the mic. Well, after all, that’s why the cymbals sounded so good. Naturally I reached for a good EQ, and dialed in a little treble boost on the Waves Renaissance EQ, about 1 dB of high shelf at approximately 8 KHz. Things changed quickly. Oooh, that sounds GOOD. The smooth, undistorted treble of this mic allows you to dial in as much treble as you can stand. The outstanding transient response provides the smoothest sibilant performance I’ve heard from any large diaphragm mic. So when I dialed in the extra treble, the vocal acquired the magic sheen I wanted to hear – only smoother and clearer than that of other classic mics – with smooth consonants that required no de-essing. Male vocals, same story. The sound was warm, with a smooth, flat high-end response that asked for just a little EQ to help them sit perfectly in the mix. This time, by backing off a little more, we got just the right proximity effect that needed no mid-cut at all. End result: this mic requires less EQ than any mic I’ve ever used on vocals. We used the VM1 as a room mic on electric guitars. The amps were set up in a large 20x20x9 room with hardwood floors, and the mic was placed about 10 feet away from the amps about 3 feet off the ground. Again, the mic’s ability to focus sound was apparent, and in its omni mode it sounded almost as close and focused as the SM57 pointed right into the cabinet. Since we were using this track as an "ambient" sort of effect, we instead put the mic into its figure-8 mode and rejected the direct sound. The mic showed an exceptionally good ability to reject sounds, and the result was that the ambient track was big and roomy. The low noise floor and smooth top end really captured the room sound of the large, hardwood-floored room we were using to track the guitars, and when the amp went quiet, you could really hear the reflections happening in the room.

Next, we tried the mic in a voice-over application for a taco commercial. The mic was used in a 16-bit ProTools rig, running through a Drawmer 1960 preamp / compressor. The tracking engineer on the project was a little disappointed with the mic. It turns out that when recording voice-over for radio and TV, this engineer really looks for a big, bottomy proximity effect, and a sizzly, "excited" treble – which the VM1 was unable to produce. A/Bed against the studio’s Microtech Gefell tube mic, the VM1 did not have the exciting (though certainly distorted) sound of the Gefell. Alas, the VM1 was simply too accurate to please the tracking engineer, who decided to use the Gefell rather than to get deep into EQing the Brauner. Finally, I really wanted to hear the mic on a string instrument, so I took it over to Planet Dallas Studios where engineer Rick Rooney was cutting Milo Deering’s fiddle tracks for an upcoming Gene Tobin release. The mic was recorded through a vintage Neve preamp directly to the studio’s MCI 2" analog deck. The sound was incredible and required no EQ at all. The VM1 added real warmth and weight to the track, while it’s high-end performance captured every nuance of the instrument’s timbre. Rick really liked the high-end of the VM1, calling it "fluffy, not harsh." Needless to say, the track was a keeper.

The Man Behind the Mic

After tracking with the VM1 for a couple of weeks (and becoming suitably impressed), I was really interested in getting to know more about the man behind the mic. Dirk Brauner generously arranged to give me a half-hour of his time to talk about his history and the origin of the VM1. I found Dirk to be "the real deal." He’s polite, congenial, and utterly infected with a love of good sound. It turns out that he’s no Neumann expatriate. He’s a "regular guy" who had a religious experience with a tube mic that forever changed his life. And thus the title: Consequence of an Experience.

Tell me about yourself. What did you do before getting into the microphone business?

I am a sound engineer. I own a recording studio. I also have a great passion for electronics, and from an early age I was building radios, amplifiers, etc.. I’ve always had this passion for music and electronics, so engineering was an obvious choice.

Where did the love of tubes come from?

You could say it was destiny. I never had anything to do with tubes. All my equipment was discrete, solid-state gear. It was totally random that I came into contact with tubes. I was designing a new recording studio for a high school. They had some old recording equipment they needed to get rid of: old Telefunken tape machines, a Neumann U 47Neumann U 47, a TAB V76 amplifier, all this old stuff. They didn’t know what to do with it, so I said I’d take it, and they gave it to me.

(Incredulously) Gave you a U47?

(Laughs) Yeah, and an Neumann M 49M 49. Of course a mint condition M49 goes for about $8000 these days, but I didn’t know that at the time. They didn’t think it was worth anything, and I had no idea that it was worth anything. I just thought it was old and beautiful, and I didn’t want it to get thrown away, so I packed it all into my van and unloaded it into my garage and left it there. I had no use for it. At the time I liked the new phantom powered mics that didn’t have the large power supplies.

That was 1988. About a year later, I was doing some recording when my C414 microphone went dead. I remembered the old microphone (U47) packed away in my garage, and brought it out and used it. The sound was beautiful, it practically made me cry. I thought, “if this mic sounds this good, I wonder about all that other tube equipment.” All that wonderful tube gear just sounded so good. Sources started to really come alive. So from that moment I started collecting and studying tube designs. I got hold of everything I could that had tubes in it. I remember in 1993 I had a partnership located next door to a company that made construction equipment. They had this old jukebox — a Rock-ola – that they were throwing out, and they asked me if I wanted it. It had a tube amplifier in it, and I took the amplifier out. That amplifier is still my home stereo amplifier. It sounds so good.

What made you decide to build a microphone?

I was using that U47 microphone all the time, and I loved it. I wanted another one, so that I could have a matched pair. That’s when I found out what a good quality U47 costs!I didn’t want to spend the money on another U47, and started to think that the U47 could be improved. I wanted a mic with a lower noise floor than a U47. And a variable pattern control, so that I could fine-tune the frequency response of the mic. A dream came to me that I would build the mic I wanted.

I started looking into the mics that I loved. The M49 has a variable pattern control, but I didn’t like the proximity effect, or the transient response. I thought the U47 sounded better, but it didn’t have the variable pattern control, or the noise floor. I wanted a mic that wasn’t linear, but didn’t sound EQ’ed. I wanted a mic that was fast and had could handle transients like a small-diaphragm, but it needed to be smooth and warm like a large-diaphragm. I wanted to have a variable pattern control so that I could sit in the control room and fine-tune the response of the mic. So I decided to build my own mic. I started out with an M7 capsule like the one in my U47. I called Neumann and ordered an M7 replacement capsule. It didn’t sound like my U47 at all. You see the M7 has a PVC diaphragm, and what happens to the old capsules is that the capsule gets old and rigid, and that introduces harmonic distortion and a slight compression effect.

It softens the peaks.

Right, it compresses because it can’t move like it’s supposed to, and that also adds this harmonic distortion. Sometimes it sounds good, like my U47. Sometimes it sounds bad. But the new capsule didn’t have that sound at all. I didn’t like it.

There were other problems with trying to get the sound I wanted to hear. All kinds of things happen to tube gear when it ages. The capacitors dry out and lose their capacitance. The resistors wear, and the resistance increases. This can be beautiful. Or bad. So I also tried a U67 capsule. That one sounded closer to what I wanted but wasn’t quite right. See, the M7 has holes directly through the electrode, which is responsible for the kind of proximity effect it has, which tends to be a little boomy. The U67 was made to lower the proximity effect. I felt that the M7 had too much proximity effect and the U67 didn’t have enough. It was a trial and error process. It took three years to get the capsule design right. The end result is the VM1 capsule. It has good bass response, but it also goes very high. If you have the equipment to measure it, you will find that the top end goes well above 24 KHz. I hand wound the first output transformer for the VM1. It sounded very bad (laughs). Maybe you can hand-wind a guitar pickup. It doesn’t make a good output transformer. So we found the manufacturer of the original output transformer used by Neumann, and they now make the VM1 transformer.

I noticed that the mic has a very fast transient response and very smooth, silky high end. The sibilants in particular are always smooth. How did you achieve that with a large diaphragm?

That’s another thing that’s different about the VM1. I wanted my mic to be very fast. Most amplifiers use negative feedback in their designs to stabilize the amplifier against oscillation, to improve impulse response, and to make the amplifier more linear. The problem with negative feedback is that there’s no way to inject truly 180-degree out-of-phase feedback. When you sweep the frequencies you feed into the amplifier you will always find some phase distortion, which blurs the transients.

The VM1 uses no negative feedback. The amplifier is made linear and stable by finding the exact LC working resistance to exactly match the impedance requirement of the tube. It’s a lot more difficult. We have to exactly tune the resistor network to the tube.

How has the business been?

My friends said I was crazy to build a microphone. They said, “You will never sell that microphone!” But it was just a dream for me. If you hang onto a dream, then you don’t care about all these people (laughs).I couldn’t have done it without my wife (Gabi). She helped me when I was starting out. There were several years where she worked to make a living while I built the microphone. She is also a sculptor. And, she designed my logo.I built the first prototype VM1 in 1994, and I sold my first microphone in 1995. Since then I continue to learn more about microphones. I have found new components, new cables, new ideas. You would not believe the difference even a different cable can make in the sound. So I am still learning. The sound will continue to improve.

Conclusions

The Brauner VM1 offers a unique combination of large-diaphragm warmth and small-diaphragm accuracy. The fact that it brings the best of both large and small diaphragm sounds together makes it unusually useful and flexible. I do not know of another large diaphragm mic that offers its low noise and detailed accuracy, and surely no small-diaphragm mic competes with its richness and warmth. The low noise floor, the excellent high-end frequency response, the wide dynamic range, the high headroom, and the excellent transient response combine to create a fantastic and original sound. The sound is clear, uncovered, and present. On all performances, it sounds like the performer is right with you in the room. It is a no-compromise mic that would be at home in virtually any recording situation from classical to jazz to country to rock.If you are looking to add a high-end mic to your collection, and you are considering a vintage mic like the U47 or C12, you really owe it to yourself to take a listen to the VM1. It will do real justice to your vocals and dynamic sounds like percussion and horns, as well as offering a viable alternative to a small-diaphragm mic on detailed acoustic sounds like cymbals, acoustic guitars, and violins. The Brauner VM1 is certainly destined to become a prized collectible microphone.

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