Scrounging up recording equipment

At the beginning of 1967, when Sonobeat co-founders Bill Josey Sr. and Rim Kelley“Rim Kelley” was the pseudonym used by Sonobeat co-founder Bill Josey Jr. as a radio deejay in Austin, Texas, during the 1960s and as a Sonobeat producer from 1967 to 1970. were planning the launch of their Austin, Texas-based record company, they were faced with a proverbial shoestring budget. Unable to afford recording equipment, they arranged to borrow professional ElectroVoice microphones and Ampex 350 and 354 tape decks from KAZZ-FMKAZZ-FM was the second FM station licensed to the Austin, Texas, market, commencing broadcast in October 1957 on 95.5 MHz. Sonobeat co-founders Bill Josey Sr. and Bill Josey Jr. both worked at KAZZ from fall 1964 to January 1968, Bill Sr. initially serving as commercial sales manager and then as station manager and Bill Jr., using the air name “Rim Kelley”, as a deejay and later as program director. KAZZ was sold to country station KOKE-AM in January 1968, its staff pink-slipped and its call letters changed to KOKE-FM. KAZZ’s frequency, 95.5 MHz, is now assigned to KKMJ-FM in Austin., where they both worked. Although KAZZ had a small monaural mixer in its production room, which was used to record local commercials, it wasn’t capable of mixing multiple microphone channels needed to record a musical act. And, as they were starting out, the Joseys couldn’t afford to buy a professional mixer, which cost tens of thousands of dollars, so they asked KAZZ chief engineer Bill Curtis, who had designed and assembled the station’s production room mixer, to design a compact, battery powered stereo mixer that could handle multiple inputs. Thus set in motion Sonobeat’s decision to build its own custom mixers rather than buy expensive commercially-available mixers (although Bill Sr. did purchase a professional mixer-in-an-attaché-case in 1968 to make tape deck-to-tape deck recording easier). In all, Sonobeat built progressively more complex mixers, culminating in 1970 with a sophisticated 3-section, 16-input, 4-bus console.

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The 6-input Curtis stereo mixer (1967)

Bill Curtis’ design for Sonobeat’s first mixer was clean and simple, using only metal-oxide semiconductor field-effect transistors (MOS-FET), capacitors, and resistors. Although field-effect transistors had been in use for several years, it was only in the mid-’60s that the metal-oxide variety was invented, and they were revolutionary. Curtis chose the MOS-FETs because they were inexpensive, needed no audio transformers, used very little voltage and current (so the mixer could be battery powered), and were easy to configure into both audio pre-amp and line driver circuits. And, this new type of transistor was the first to beat the “quietest” vacuum tubes, introducing no perceptible thermal or shot noise – hiss usually associated with transistorized audio amplifiers – into the audio chain. It was because Curtis used MOS-FETs for the mixer that Sonobeat decided to prominently feature the alliterative "“Solid • State • Stereo” – a reference to semiconductors, such as transistors, as distinguished from vacuum tubes – on Sonobeat’s record label.

Bill Curtis’ approach to assembling each input circuit was as simple as the circuits themselves: he just twisted the appropriate transistor, capacitor, and resistor leads together and added a drop of solder to each twist, creating a small open-air ball of components for style="margin-bottom: -2px;">Bill Sr. built a small wooden box – about eight inches high, six to seven inches deep, and 16 inches wide – to house the circuits and dressed it with a brushed aluminum faceplate into which he drilled two rows of six holes each to mount the volume and stereo pan controls. He mounted XLR microphone connectors and quarter-inch line input and output phone jacks on the back of the box. Curtis then soldered his preamp circuits into place, leaving the balls of transistors, capacitors, and resistors dangling inside the box. He was careful to separate the components so they didn’t short out. To make it easy for Curtis to tweak the circuits as needed, Bill Sr. left the bottom of the box open. Although we little mixer was long ago abandoned for a more sophisticated mixer, we haven’t found photos of it nor Bill Curtis’ schematic drawings in the Sonobeat archives; however, Rim recalls it was modeled on and looked similar to the KAZZ-FM production room mixer. In 2016, Rim recreated a set of elevation drawings from memory.

The Bill Curtis portable mixer got its acid test in May ’67 in a series of practice recording sessions with Austin rock band Leo and the Prophets. Those sessions led to circuit tweaks before the first “formal” recording sessions Sonobeat held, in July 1967, initially “redo” sessions with Leo and the Prophets followed by sessions with the Lee Arlano Trio, an acoustic instrument jazz combo, and, a week later, the Sweetarts, a definitely amplified rock band. If there was one serious failing of the little mixer, it was that it lacked volume unit (VU) meters to gauge when a microphone input was set too high and, therefore, Rim couldn’t tell when the mixer’s circuits were overloading and distorting during recording sessions. By the time Sonobeat held the Sweetarts session, Curtis had worked out a clever calibration method using a small portable audio frequency generator set to 1000 Hz that he ran through one input of the mixer and from its stereo outputs into the Ampex 350 and 354 inputs. After the calibration, Rim could monitor input and output levels during recording sessions using the VU meters on the Ampex tape decks. Although a good solution, it wasn’t perfect, and many of Sonobeat’s early recordings indeed were distorted from circuit overload. Nonetheless, Sonobeat continued to use the Curtis 6-input mixer until March 1968, when Bill Sr. and Rim built a new 10-input mixer.

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The 10-input suitcase stereo mixer (1968)

By the end of 1967, Sonobeat was rapidly outgrowing the 6-input Curtis mixer, although it provided yeoman service in recording the first group of 45 RPM singles and first album that Sonobeat released. But by 1968 Sonobeat wanted to use more sophisticated microphone techniques as well as “direct injection for bass guitar and electronic keyboard recording ” – plugging guitars directly into the mixer, bypassing the guitar amp and speaker box altogether –, so adding more inputs became the number one priority for a new mixer. Rim began researching audio amplifier circuits early in 1968. Using plans sourced from articles in Popular Electronics and Radio Electronics magazines, he laid out printed circuit board matrices that Miller Blueprint in downtown Austin turned into high-contrast negatives. The negatives were then used with Radio Shack printed circuit board etching kits to create the actual copper-clad epoxy boards onto which all the components were mounted. Bill Curtis’ 6-input mixer used field effect transistors, but for the new mixer Rim chose Motorola audio integrated circuits that offered more powerful features. Other components rounding out the circuits included standard transistors, capacitors, resistors, and audio transformers. This mixer also was battery powered, but took a bigger battery pack than the Curtis mixer.

Now, how to house the new printed circuits boards and control surface? Another wooden box, but bigger than the Curtis mixer? Bill Sr. saw a TV commercial for luggage that could withstand being run over by a truck. That triggered an idea: since Sonobeat had no studio facility and generally recorded at a variety of rented locations around Austin, such as Swingers Club and The Vulcan Gas Company, the Joseys had to cart their equipment everywhere they recorded. So, Bill Sr. decided to mount the new mixer in a small suitcase with a detachable lid. He cut a piece of black acrylic plexiglass to precisely fit flush at the surface of the bottom half of the suitcase, then drilled holes into the acrylic for the volume and pan controls. This time, he added VU meters to more accurately gauge and control input and output levels. He installed XLR connectors and quarter-inch phone jack inputs on each side of the suitcase and mounted suction cups on the bottom to hold the mixer in place when in use. Meanwhile, Rim assembled ten identical sets of the printed circuit boards, each containing a microphone pre-amp, line input, and line-level output, plus one printed circuit board that combined the outputs of the ten input circuits to feed the VU meters and the Ampex 350 and 354 tape decks.

Somewhat surprisingly, when the printed circuit boards were assembled and mounted under the plexiglass control surface and mikes and tape decks were all plugged in, everything worked. The new 10-input mixer was in service by the time Sonobeat recorded Lavender Hill Express’ single Watch Out! and Country Music’s Here to Stay in March ’68. This mixer stayed in service until Bill Sr. and Rim built an even more powerful and sophisticated mixing console early in 1970.

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The 16-input 3-piece mixing console (1970)

In late summer 1968, Sonobeat acquired a high-end Scully half-inch 4-track recorder, which gave the Joseys the ability to undertake more elaborate, layered recordings. Although the 10-input suitcase mixer was serviceable throughout 1968 and into 1969, it eventually couldn’t handle ever more complex recording sessions. As 1969 came to a close, Rim began researching a modular approach to combining audio circuits that could provide an array of functions – including compression, equalization, and reverb – separately for each microphone and line-level input channel. He turned to db: The Sound Engineering Magazine, which featured scholarly articles on recording console circuitry, but he also bought a book filled with audio circuit designs that he found in the Electrical Engineering section of The University of Texas bookstore. Armed with an array of potential circuits, in January 1970, he began laying out circuit designs for each input channel and eventually created larger and more sophisticated printed circuit boards using the same process he had used for the printed circuit boards in the 10-input suitcase mixer.

Because the new console included an ambitious professional-level feature set, Rim created separate printed circuit modules for the various functions, including a board that allowed each of the mixer’s 16 individual input channels to be assigned to any of the sub-mix busses feeding the Scully 280 and newly-acquired Stemco 450 half-inch 4-track tape decks. Bill Sr. decided the console itself also should be modular and built three separate units that neatly fit together to form an “L”. The main unit was five feet wide and housed the 16 side-by-side individual input channel “strips”. Each vertical strip featured a linear slider volume control, knobs for microphone trim, high and low equalization, reverb and effects send and receive, compression functions, and headphone send, along with switches to assign the strip’s output to any of the sub-mix busses. On the right side of the mixing surface were 16 linear sliders mounted horizontally but stacked vertically; each provided stereo pan for its corresponding input strip. Running the full length at the top rear of the main unit was a panel housing a VU meter for each channel strip. All printed circuit boards and electronic components were mounted inside each respective console unit. Although all three units were framed and covered in wood, the surfaces, onto which all the controls were mounted, were made of black acrylic plexiglass. The back of the main unit included XLR microphone jacks and quarter-inch phone jacks (for line level inputs) for the 16 input channels. Each of the two side units was about 30 inches wide. One housed the four-channel mixing busses, with a VU meter for each of the four channels. The other housed a patch bay that assigned output channels to the half-inch 4-track Scully 280 tape deck, half-inch 4-track Stemco 450 tape deck, or Ampex AG-350 quarter-inch 2-track tape deck as well as to and from outboard processing equipment, including Sonobeat’s Blonder-Tongue Audio Baton 9-channel equalizer and Fairchild Lumiten stereo optical compressor. Eventually, because it took up too much space in the small studio, Bill Sr. abandoned use of the unit housing the patch bay, which was largely superflous since there also was a patch bay on the equipment rack that held the tape decks.

The 16-channel main console unit was completed just in time for the complex Mariani Perpetuum Mobile album recording sessions in March 1970, initially recorded in open-air at a 100 acre ranch near Austin, where Bill Sr. and Rim hauled their Scully 280 4-track tape deck, the main mixing console unit, and microphones and cables.

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The quad modifications (1972)

At the end of 1969, Rim saw an article on “tetraphonic” sound in db: The Sound Engineering Magazine. Consumer electronics companies already had begun touting this as the next “big thing” in consumer audio but decided to use a friendlier term to describe it: “quadraphonic”, in which the listener is surrounded by four speakers – front left, front right, rear left, and rear right – to deliver an encircling sonic experience. It's almost like being in the middle of an orchestra or band. Although Rim put the magazine away, a year or two later Bill Sr. recalled it, anticipating quadraphonic recordings would become a big consumer trend. In 1972, about a year after Sonobeat had relocated its studios to 705 North Lamar in Austin, Rim designed a new set of sub-mixing printed circuit boards that made it easier for Bill Sr. to create quad mixes that literally surrounded the listener in 360°. These new printed circuit boards were designed to connect to joysticks that would position the instruments and vocals anywhere in the quad audio spectrum, but Bill elected to use two pan pots for each quad module: one moved the audio image from left to right and the other from front to rear, which accomplished the same feat as the joystick but at significantly less cost. Bill began experimenting with quad recording techniques, initially using Austin musicians he brought together into a studio session group he called Base. His first commercial attempt at quad recording, in early 1973, was with Austin band Vita, but the quad fad fizzled out quickly because there were multiple, incompatible competing systems that confused consumers and made marketing quad recordings too challenging for record companies.

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Disappearing act (1976)

In August 1973, the 3-piece 16-input console moved from Sonobeat's North Lamar studio to Bill Sr.'s new Blue Hole Sounds studio in Liberty Hill, Texas. The console remained serviceable into 1976, when Blue Hole Sounds shuttered just before Bill's death in September. Within weeks after Bill's death, his son visited Blue Hole Sounds to recover his dad's belongings, only to find cardboard boxes filled with Sonobeat's master tapes crammed into Bill's station wagon. But all the recording equipment, including the mixing console, was missing from the studio. Where the equipment went remains a mystery to this day.