Osiris - Searching for the Sound

The Low Impedance Single Coil Pickups in Osiris were custom wound by Rick Turner and included a Hum Cancelling Coil. The pickups utilized a preamp circuit similar to the Alembic Series 1&2 basses. Each pickups preamp had its own gain control as well as a hum balance control for the hum cancelling coil, wound out of phase of the single coil pickup, to provide the hum cancelling function. Similar to a Humbucker’s design, the difference is the hum cancelling coil doesn’t have a magnet. This allows for the hum cancelling function but with no output of the hum cancelling coil due to the lack of a magnet. This configuration can be adjusted with a preamp circuit added to the hum cancelling coil. The optimum hum cancelling setup procedure for the single coil pickup and hum cancelling coil was to adjust each set, pickup and hum cancelling coil, individually. Starting with one pickup and hum cancelling coil the user first sets the gain of an individual single coil pickup. Then physically moving the bass in the direction of the most noise the user then adjusts the hum cancelling pickups hum balance control to mitigate the least amount of hum. Once that pickups gain and hum cancelling balance is set, the second pickup could then be adjusted in the same manner with the firsts sets volume turned off. This is also a standard setup for Alembic basses with hum cancelling coils. The output of each pickups preamp was split and fed 2 signals, one to that particular pickups filter input and the second to its own unfiltered Direct Volume control.

The filters, per George Mundy who was responsible for all the electronic work with Osiris, were active Biquad Filters. Although Mundy added the filter design to Osiris, Ron Wickersham first added a similar version in Big Brown and looked over Mundy’s shoulder in Mundy’s filter design for Osiris. Like Big Brown, Osiris had four filter selections, High Pass, Bandpass, Low Pass and a Notch filter. These were controlled with a 4 way rotary switch, one for each pickups filter. Another control was the Frequency which set the center frequency for each of the filters. A frequency range of around 45 Hz up to 6 kHz was achievable with the Frequency control for each pickups filter. A fourth control was for the Filter Volume, again one for each pickups filter. The Filter Volume and the Direct Volume could be utilized at the same time. This allowed Phil to use the Direct Volume by itself with no filter, or use the Filter Volume by itself with no direct signal, or a mix of the two, allowing for deep low end tones or crispy high end tones or anything between depending on the setting of the Frequency control. The fifth control, again one for each filter, was the Q Control. It set the bandwidth of the center frequency selected. Lastly there was a Master Volume control that controlled the overall output of all, the direct signal, the filtered signal or any combination for both pickups. 11 knobs total, 5 for each pickup and 1 master volume!

There were 2 Quadraphonic Pickups built into Osiris. The Quad pickup on Osiris was located in the same location as Big Browns Quad, between the neck and bridge pickups, and was used with Phil’s rig when it was setup for its use. Neither Quad pickup went through the filters or the master volume control of the bass. Lesh has stated he did not use the Quad pickups all that much as he found that the effect was only heard close (about 50 ‘) to the speaker stacks, by the time it all traveled to the audience it all melted into one. He had also stated that the timing of the Quads individual pickups delivery through each of the speaker stacks from the bass was disorientating to the band when used. On Osiris, the 4 pickups of the Quad, one for each string, had their own preamps with individual gain controls. Similar to Big Browns internal individual trim pot gain control for each preamp of its Quad pickup, Osiris’s Quad preamp gain controls were individual trim pots located on the front of the bass with access for screwdriver adjustment for each string without the need to open the electronics cavity. The trim pots allowed for the individual outputs of each string to be balanced. Big Browns Quad pickup however had a master volume which is four stacked potentiometers on one shaft/one knob, while Osiris did not have a master volume control for its Quad pickup on the bass.

Osiris Quad Pickups

Phil had initially also wanted the bass to be a controller for an outboard synthesizer. The second smaller sized Quad pickup was designed into the bass and was inserted between the bridge pickup and the bridge for this potential synthesizer application. The Grateful Dead Newsletter #19 from December 1974 stated it was a Frequency-detector pickup. Its placement was due to its ideal note separation per Rick Turner. Also, Turner designed the frequency-detector Quad pickup with circular magnets versus the middle Quads oval magnets. The Osiris build started in 1972 and the Quad Frequency-detector pickup was seen in the bass in photos as early as 1973. Phil first plays Osiris onstage on June 16^th 1974. The first production guitar synthesizer, By Roland, and Hexaphonic pickup for a guitar doesn’t arrive until 1977. Unfortunately the Bass Synthesizer Phil had dreamed of with Osiris as the controller did not pan out and it was eventually abandoned. Never could reach it, just fades away, but I try…..

Special NASA grade parts, 18 pin Lemo jacks and plugs, were acquired by Mundy through his prior work at CERN and were utilized to accommodate all the outputs and power to and from the bass. A special rackmount enclosure was used to supply power to the bass and distribute all the outputs from it.

Rick Turner is credited with the making of the bass and pickups. However Doug Irwin pointed out he had made Osiris’s first triple pickup ring made of Koa with Abalone inlays. It was changed to a brass version with some custom decorative etchings on it. George Mundy was hired by Ron Wickersham for his synthesizer work the day he walked into Alembic in 1971 with the synthesizer he had brought and demonstrated that he had made from a kit bought at an electronics store in San Francisco. George’s synthesizer knowledge was the reason Wickersham assigned him to be responsible for the electronic work of Osiris from the start. A side note worth inserting, George Mundy was also the person who went to get Doug Irwin out of the shop in back the day Jerry Garcia walked into Alembic’s storefront and bought Irwin’s Eagle guitar and subsequently commissioned Wolf. Mundy ends up leaving Alembic’s employment to work directly for Phil and the bass, at Phil’s request, as part of the GD crew. Mundy‘s work on the crew ended when he was fired by the Grateful Dead just after his appearance in the Grateful Dead movie. However he would continue to perform work on Osiris when work was needed up until its last use by Lesh in 1979.

George Mundy – Grateful Dead Movie

Zig Zag #46 Sept 74

"The system that I was going to have built is not happening because the guy who was going to build it completely crapped out in the middle of the job. I have the bass with all the switching on it and I've got the frets for the console with all the tone modulation modules, and the foot pedals with all the switching on it and stuff, but that's it, and right now I'm using a ring modulator.”

"The instrument, as it was originally conceived, would have been at one end of the spectrum an electric bass with which you could play rock 'n' roll music but in entirely different tone colours, new tone colours. Like every note would have a change in it rather than just being a note that was attacked, sustained and then died away. During that period it would change internally, that was what I was after on one end of the spectrum. On the other end of the spectrum it would have been a synthesiser which would have been controlled by the strings of an electric bass, so that I could still use my hands to play the electric bass, which I've learned to do fairly well in ten years, and still have a synthesiser to modify the sounds and make a new kind of music with this relatively simple instrument. Unfortunately, that didn't happen so what I have now is a super electric bass which is real easy to play, and has all kinds of great tone colours just for the electric bass, but it doesn't have that synthesiser capability of being able to change or, like, play around and say every note have a different tone colour and that kind of thing. That's what I was really after and it just hasn't happened. It's possible that something like that could happen in the future, but with the present synthesiser technology it's just real difficult because everything is voltage controlled and you get voltage out of an electric bass but it's voltage according to amplitude — how loud you play, not what you play, and the hang up of the system that I was going to have built was that we couldn't get a frequency to voltage converter. That is something that will pick out what note you are playing in the audio spectrum and convert it to voltage, a certain amount of voltage, which would then cause your filters, or whatever else you wanted to use, to track along with what you were playing. So it's like still in the future but I do have a great electric bass, it's just a flash, it's just a trip to play. The people from Alembic built it essentially. Rick Turner built the wood, built the instrument itself and the pick-ups, and George Mundy who is an electronic technician, you might call him, he used to work for Alembic but now he's on his own, he's freelance."

Grateful Dead Newsletter #19 Dec 1974

Bass Player April 2008

Karl: Today’s bass technology owes a lot to the Alembic electronics you were involved in early on.

Phil: Yes—the Grateful Dead was driving that. I wanted more tone out of the bass; I wanted to be able to boost any area of the frequency spectrum. But most of all, I wanted the tone to be consistent across the instrument’s whole range. We talked about having tracking filters, where the frets were wired—so every time you fretted a note it would close a circuit, the instrument would know what note it was, and it would send a signal to an outboard filter, which would then shift so the filter’s center point was the root. The tracking-filter idea never caught on, though. Neither did the quad bass we developed, where I had one amp system for each string—although that was amazing the few times I tried it with the Wall of Sound. I had two bass speaker columns, each 30 feet high. I think there were 16 speakers in each column. So I had eight speakers for the E string, eight for the A, and so on. But it never went far enough; I should have had footpedals to change the configurations. It was also impractical: In order for it to work, the speaker sets needed to be separated—but in that case the pattern wouldn’t make sense to any one musician onstage. It would make sense only to someone standing 50 feet in front of the stage.

What Happened to Osiris?

(Excerpts from Forum Post’s found online)

Fred Hammon:

"I'm told these are the original pickups out of Phil's Alembic Osage bass. Phil had given it to somebody in his road crew who was a machinist for some R&D work.. These pickups were apparently just in the way....

(the photos of the pickups that the thread author posted)

He traded them for a set of Dimarzios to our Pitter friend sometime back in '79 or so.

I took some measurements. The DCR measured in at 2.93K ohms on both. Exactly the same within 10 ohms. Good Job RT (Rick Turner, a member of the forum) ! The magnets measure approx 380 Gauss at the surface (DSs measure 450 average) and the polarity is north on both. Not RWRP. There apparently was another coil (dummy coil?- dark color) that was with the set but our friend couldn't get it. I understand that the bass originally came with a quad pickup in the center so there are some missing parts to the puzzle. He knows that these came from/with the Osage because he saw it. These are definitely very early hand made Turner pickups. Look at the brass mounting lugs. Definitely a prototype vibe.

The tech's name was Tom Smith, otherwise known as "Turbo Tom" who was also working on race cars or something in Detroit at the time and experimenting with bridge designs at night. The Osage was going through some major modifications, as in body routing etc. Anybody seen it lately? They're safe and sound at Hammon Engineering now. Maybe Rick Turner will want them...or even Phil? I've asked for a detailed account of how these came to be in our friend's possession so maybe he'll feel like posting it for anybody who's interested. Looking at the pickups on Phil's bass in the photo and these pickups, I see a slight difference maybe. The pickups I have look more rounded at the edges especially in the corners. Possibly they were part of a collection of different pickups that were used in the bass over time. Where's RT? Answers, please!"

Pitter:

" Hi guys, I'm the "silent" pitter who Fred was talking about. I'm not all that silent, I've just never posted in the Guild forum before. I just finished the little essay about my experiences way back when with the Osage Orange bass. He suggested that I post it here, so here it is: (Please excuse the goofed up format. It's late and I just pasted the text into the reply)

One Saturday morning in early 1981 I got a call from a guitarist friend, Leon Chalnick, who told me that he’d had an interesting conversation with a guy at the bar where his band was playing. He said the guy told him that he was from the Detroit area, but had moved to California and was a part time roadie for the Grateful Dead. He was back in town for a few weeks doing some freelance machining work during the day and he needed a pickup for a bass he was working on at night. Leon told him that he knew someone who played bass and did some work on guitars and basses (me) and that I might have something that would work. I asked him more about what the guy needed and he said that he was meeting him for lunch and asked me to come along. When we got to the restaurant, Leon introduced me to Tom Smith and we sat down to eat and talk. He explained that he used to work at McLaren Racing Engines there in Livonia, Michigan, building custom turbo charging systems for BMW racing engines and got the nickname “Turbo Tom”. He was back at McLaren for a few weeks doing some custom fabricating of parts for a helicopter that the one of the top guys at McLaren was restoring, and at night he had free use of the machine shop to do development work on some bass bridges for Phil Lesh. He said that he had been loaned one of Phil’s old basses to use as a test bed but didn’t want to deal with all the electronics that were in it and just wanted to put a passive pickup in the bass for testing the bridge designs. Well, being somewhat of an Alembic fan, that certainly got me intrigued and I told Tom that I could certainly find a pickup for him.

After lunch, Tom invited us to come over to the McLaren machine shop to see the bass and get a tour of the facilities there. After showing us around the machine shop and the engine testing dynamometers, he took us back to his work area and pulled out a road case and set it on the table. He told me to go ahead and have a look so I went over and opened the case. I couldn’t believe my eyes! I recognized the bass as the one that Phil Lesh played in the Grateful Dead Movie that I’d seen a few years prior. I remembered the scene where he was sitting on stage before a sound check, fiddling with some of the controls on the bass when he started picking up some noise. When he realized that it was motor noise from the film camera, he motioned the camera operator to come closer and started manipulating the motor noise with the electronics in the bass. Here was the same bass, right in front of me! I distinctly remember several touch switches on the face of the bass, the fingerboard inlays, and if I remember correctly, five pointed stars in pearl or abalone with 5 controls around each of them. (Bear in mind that that was about 24 years ago, and we all know what can happen to our minds in that amount of time…) I was amazed that such a beautiful instrument was going to be used as a test bed for bass hardware and asked Tom why they were using it. He told me that it had been sitting in a closet for the past several years because it had intonation problems due to incorrect placement of the first three or four frets. He said that Phil Lesh told him to make use of it and that once he removed the electronics he was going to mill out the face to install a magnesium plate to mount various bridge designs and pickups on. I figured it wasn’t my place to question what they’d decided to do so I didn’t, but in hindsight, I wish I’d asked more about it. Tom asked if I had a cheap pickup that he could buy to use for testing. He said he didn’t have much to spend and I didn’t have any spares to donate, so I offered to buy a pickup for him if he’d be willing to trade the pickups in the bass for it. He said that he was supposed to return the electronics pretty much intact, including the middle pickup, but since the other two pickups weren’t anything special he could trade those. We arranged to meet there again in a couple of days and I promised that I’d have a pickup for him then. I asked if I could at least take a look at the electronics and he said that was fine, grabbed a screw driver and proceeded to remove most of the back of the instrument. As I recall, the center neck section was solid, but pretty much the entire back half of each body wing came off and it seemed like each half was filled with at least two layers of high quality circuit boards. Tom said that he’d have the pickups out of the bass when we returned.

Two days later Leon and I went back to the McLaren machine shop and Tom led us back to his work area. He pointed to the case and said to check it out. I opened the case and there was the bass, minus all the electronics, and there was a metal plate, about 6 inches wide that extended from the end of the fingerboard to almost the end of the body. It broke my heart to see that! Tom handed me a box containing the two pickups and I gave him a crème colored DiMarzio bass humbucker that I’d bought the day before. We hung out for a while and talked, then left. That was the last time I saw Tom or the bass.

A year or so later I decided to see what I could do with the pickups. I was working as an electronics tech and thought that maybe I could come up with some sort of preamp circuit to work with the pickups. I knew that the pickups were probably single coils wrapped on a magnetic structure and that Alembic typically used a dummy coil for hum canceling, but that’s as much as I knew. I figured that I’d at least try the pickups through a simple opamp circuit, but when I did I found that they were very microphonic with low output, so I put them back in the box and back on the shelf. I figured that there were probably impedance matching issues and that without a dummy coil there’d be hum problems, so I set the project aside for a while.

24 years of parenthood and life later I was reading about Dark Star pickups and Guild basses in the Dudepit forums, which led me to the Hammon Engineering and Turner Guitars web sites and Rick Turner’s Guild of American Luthiers interview. Somewhere in all that reading it dawned on me that I’ve got an old pair of Alembic pickups, supposedly from one of Phil Lesh’s early basses and that Fred or Rick might be interested in seeing them. They were just collecting dust in my basement and I felt that if they were of any historical significance I should get them into the hands of the people that are documenting that stuff. I emailed Fred to see if he was interested in them, we talked and I sent them off to him a couple of days later. So there’s my story. Do with it what you will. All I ask that is that you let me know if it’s of any use.

In my "essay" I forgot to mention that the pickups originally had some cool micro coax connectors on the leads that pushed on to corresponding jacks on one of the circuit boards in the bass. I was never able to find the jacks anywhere and so I removed the coax connectors and hard wired the leads for my "experiments". A couple of decades later I came across the same kind of connectors used in some studio quality video gear. The connectors that had been on the pickups were long gone so I didn't pursue it any farther.

In our conversations, Fred asked about a black quad output pickup that was known to be mounted between the two regular pickups at some point. There was in fact a third black pickup mounted in the middle when I saw the bass, but I assumed that it was the dummy coil that was used for hum cancellation and never got to check it any detail."