Wally Heider’s First 3M 8-track

Wally’s First 3M 8-Track

3M 8 track Front

Wally Heider was always willing to play a hunch. If he thought something new could be successful, he was willing to be the first one on the block with the new toy. One of his hunches was to buy the first 3M Isoloop 8-track recorder ever delivered. That hunch paid off immediately.

Wally’s 8-track was among the first 3 machines to be hand-built by the design team at 3M Mincom. The other two machines consisted of a 1/2″ 2-channel Dynatrack-only machine delivered to Ross Ritchie at the Marine Band in Washington, and a 1/2″/1″ 4-track shipped to Rolf Epstein at the Film Board of Canada.

Wally’s machine was unique. During the design process for the second-generation NAB/Dynatrack machine, a design company, Ford and Earl Associates of Troy, Michigan, was commissioned to come up with the industrial design of the machine and mounting cabinet. One of their first questions was “Can’t we get rid of that terrible buff color on those meters?” Well, they certainly lost that battle, but the console design was very impressive. The machine was mounted in a walnut grained cabinet using contoured sheetmetal and Heliarced wraparounds. The cabinet was mounted on a bird-foot pedestal with 4 casters – similar to a desk chair.

Unfortunately, after the first two prototypes of the console were built, that technique was way too expensive. The compound rolled corners and Heliarced aluminum were completely overbudget. The console was redesigned with flat sheetmetal pieces and a deeper (horizontally) wooden box that brought the lower electronics modules forward for better viewing and access.

The redesign changed the transport from what had been a standard 19″ rack-mountable transport surrounded by a border of metal to a single 24″ wide unit. Since Wally had also ordered a set of 3 Halliburton portable/shipping cases for his machine, we offered to give Wally one of the two prototype sets of console sheetmetal so that his transport would be the 19″ configuration that could be easily transplanted into the portable cases for field use. (I have the other prototype transport pan on a 4-track machine in my collection. Somewhere along the line I gave away the prototype upper support for the signal electronics.)

Wally’s machine (ignoring the special sheetmetal) was probably the first standard production 8-track 1″ machine to be delivered. Ampex had built some custom 8-tracks using various types of Ampex electronics modules. By comparison, Wally’s machine was “stock”, straight out of the catalog. Part of this was due to the anticipated need for 4-channel Dynatrack, which would have required 8 tracks on 1″ tape. As a result, everything was designed for 1/4″ through 1″ operation.

After Wally took delivery of the machine, he began renting the recorder at a pretty hefty rental rate. I think the price of the machine was about $12,500, and Wally was renting it for something like $1,250 a week. Needless to say, it didn’t take long to recover his investment.

One of the first rental customers was Sunset Sound, and a lot of Herb Alpert’s recordings were done on this first 8-track. But Wally had even more ways to make money. The normal rental week at Sunset Sound was Monday through Friday. Wally quickly figured out that he could pull the machine out on Friday night and use it for weekend remote recordings!

At the time, I was living on the beach at Oxnard. One Saturday morning I got a call from Wally. He was down in San Diego with the machine, recording a remote at Mickey Finn’s. Mickey and her husband Fred had become popular as a summer replacement TV show, and Wally was there to record an album. The music was Dixieland piano and there was lots of beer to drink and peanut shells on the floor. Wally invited me to hop on a plane and fly down to San Diego for the Saturday night recording.

Now the truth was that Wally and his boys were intimidated by their new 3M machine. If it broke, they didn’t have a clue of how to fix it! Wally wanted me as insurance.

When I arrived, someone picked me up at the airport and they took me to the restaurant. Wally casually mentioned that maybe I could give the machine a quick check to see that everything was OK. Once that was completed, I just drank beer, ate peanuts and enjoyed the show. Nothing happened to require my services, but I was cheap insurance.

I remember driving back to L.A. with Wally and the fellow who wrote the “Gunsmoke” theme. That was back in the days when they were still building the freeway from San Diego to replace the old “Blood Alley” highway, known for its high fatality rate.

Wally was eager to promote the new 3M machine, including the Dynatrack feature. He had an Open House at his studio to demonstrate Dynatrack to everyone. He asked his friend Anita Kerr to provide live music for the demos – a capella singing. Our 3M team was there to provide technical support and answer questions.

Perhaps a small digression to explain Dynatrack would be in order. In the early ’60’s things were fairly stagnant in the tape recorder world. Ampex was selling minor re-dos of the 300 and 350 transports, and 3M was still selling Scotch 111 recording tape. Apparently 3M was getting some heat that they were stifling the market by not offering a new tape.

At this time Jack Mullin had a lab, and their primary effort was connected with an electron beam recorder being developed to record video. The electron beam was used to scan a moving film of thermoplastic media, writing a modulated signal onto the film by thermal deformation. The playback device used Schleren optics to read back the signal. Dr. Dick Dubbe was in charge of the recorder, and Jack was building the playback device.

Dubbe was behind schedule with his development. As a result, Jack and his group were in a holding pattern waiting for media so that they could test their playback system. Jack spoke with Dr. Wetzel, the big honcho in St. Paul for the entire group, about using the available time to create an innovative audio master recorder that would provide significantly better performance with Scotch 111 tape.

There were two aspects to the new design. First, the transport would employ some of the advanced technology that had been developed for wideband instrumentation and video recording. Features such as greatly reduced flutter, dynamic breaking and “intelligent” logic to prevent tape breakage were at the top of the list. Ken Clunis and Don Kahn were responsible for adapting the 3M Isoloop tape path to an audio-format machine that provided easy editing. Ken also developed circuitry to implement Jack’s improvements in audio performance described below.

To complement this improved transport, Jack had an idea to use two tracks for each channel of audio to extend the dynamic range of recording. Jack probably wasn’t the first person to try this method, but he was the first to produce a system that caused no undesirable artifacts. Many people were working with various compression/expansion systems, including EMI, who had invested a lot of effort into companders.

First Jack tried simply offsetting the record levels by 10 dB. A trigger circuit monitored the playback output of the boosted track, and when that track started to approach a level that created excessive distortion, the circuit switched over to playing back the unboosted signal on the other track. The boosted track offered lower noise (thanks to the signal being boosted above the noise due to the increased input level), and the normal track offered lower distortion on peaks. All switching was done on playback, which meant that there wasn’t any need to critically synchronize the playback switching operation with something that might have happened during the recording process.

Well, it didn’t work well. If you recorded a piano or a guitar, a low frequency note would cause the playback selector to trigger, but there wasn’t any music signal out around 3 kHz to mask the increase in tape noise when the unboosted track was selected. Jack attacked this problem by using an equalizer to boost just the higher frequencies for both the boosted track and the trigger circuit. Now the system ignored signals that didn’t have enough masking energy to hide the rise in tape hiss. The equalizer was a simple double RC circuit that started at about 400 Hz, rising about 15 dB at a maximum (ideal) slope of 12 dB/octave. A complementary RC rolloff circuit was used on the output of the boosted track on playback to maintain overall flat response.

This circuit worked much better, but a few refinements were added. The trigger circuit needed to have a “hold time” (like the release time of a compressor) that avoided trigger on just the peaks of low frequency information. To assure undetectable switching, the output switcher was configured as a crossfader. The boosted signal was fed to the output through a high value resistor. The unboosted signal was fed to the same point via a photoresistor. When the photocell was not illuminated, the cell’s resistance rose to over 10 Megohms, effectively removing that branch from the output. When the cell turned on to just a few hundred ohms, this low impedance path essential shorted out the boosted track’s feed. Since essentially the same signal was arriving from both sources, the crossfade was undetectable.

The noise reduction system was named Dynatrack. The main advantages were a 10+ dB improvement in weighted signal-to-noise ratio, no nonlinear processing (compression/expansion), and no critical synchronization or tracking required between input and output processing.

The new machine sounded great! The extended dynamic range was complemented by a major reduction in FM artifacts produced by scrape flutter. For the first time many recording engineer realized just how good a tape recording could be. Up until that point they had never heard a tape recording that wasn’t contaminated by noise and scrape flutter. In some cases the results were almost unbelievable. At least the EMI engineers didn’t believe that a demo recording at Capitol Records had ever gone through a tape recorder. When they received pressed disk copies of a Dynatrack demo recording, they swore up and down that there couldn’t have been a tape recorder in the signal chain. They knew everything there was to know about noise reduction, and this just couldn’t be true!

The disadvantage of Dynatrack was the requirement to have twice the number of tracks. Trying to cheat by reducing the track widths to squeeze more tracks onto a give tape width was not the solution due to the degradation created by the narrower tracks. Another factor was the introduction of Dolby A noise reduction not long after Dynatrack hit the market. Although the Dolby processor was a compander, the use of multiple bands minimized the pumping of the background hiss on unmasked low frequency signals.

The biggest factor, however, was the arrival of true multitrack recording and overdubbing for rock and roll. When Dynatrack was developed, 3 channels were used for master recording – left, right and the vocals. This format provided enough versatility to produce stereo and mono mixes from the same master tape. The 3-track format evolved into 4-track 1/2″, but the next big step was 8-track with overdubbing. From then on, there could never be enough tracks on a tape recorder, including 8, 16, 24, 32, 40 and 48 track machines.

It is ironic that the same company that sponsored this revolutionary machine torpedoed part of the original mission of the Dynatrack. Just as the machine was being introduced, 3M brought out Scotch 200 Series low-noise tape. Now, with no change at all to an old tape recorder, the weighted signal-to-noise ratio could be improved substantially. Of course this made Dynatrack even better, too, but many studios settled for just changing tapes. And of course there was also the problem of a new incompatible format that wouldn’t play on existing machines.

Dynatrack was used by a few of the major labels for symphonic recording, and Capitol released some very quiet disks of George Shearing, Nancy Wilson and Nat King Cole. Then Dynatrack slowly faded into the sunset…. Now back to the story of Wally’s demonstration of Dynatrack with Anita Kerr.

The test provided 3-way monitoring – live, Ampex 351 record/playback and 3M Dynatrack record/playback. There was no difference between the live bus and the 3M playback, but the Ampex had lots of tape hiss and other artifacts, such as scrape flutter. The demo was very convincing.

Wally sent the machine to United/Western for a Dynatrack demo during the recording of Frank Sinatra’s “That’s Life” album. Wally arranged for me to attend the second day of recording. This was my first studio recording session ever. If you have to start somewhere, why not at the top with Sinatra.

I guess they had done some Dynatrack playback the previous day, but they didn’t do any while I was there. I stood like a church mouse in the back of the control room while Mr. Sinatra recorded “I’ll Wait for You”, “You’re Gonna Hear from Me”, “Sand and Sea”, and 25 tries of “The Impossible Dream”. They finally stopped when Frank’s voice gave out. His then wife, Mia Farrow, had wanted him to record “The Impossible Dream” for her.

A few years later, Wally found the 4-track B Masters of that album in some used tape stock he acquired when United was cleaning out their tape storage area. Wally gave me a 1/2″ 4-track copy of the 2 reels done while I was in the control room – quite a souvenir!

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