Strictly ARP Centaur

gfriden · Post by **gfriden** » Fri Dec 07, 2007 3:53 am

OK, this is my attempt to create a thread that focuses solely on the technical history of the ARP Centaur VI. Please contribute any information that you feel is missing, and I hope Psy_Free and Micke would consider re-posting their Centaur VI photos in this thread. Please limit your input to the strictly technical side of things though. History is fine, as long as it records the R&D part of it, not the ideological struggles within ARP concerning this or other projects. You can read about that elsewhere and discuss it in the ‘Off Topic’ section of this forum. Below is a summary of what I have learned by googling the ARP Centaur VI.

The ARP Centaur VI

The Centaur VI was designed to become the world's 'ultimate' polyphonic synthesizer. With two polyphonic sections, a dual-oscillator lead synth a single-oscillator bass synth and a polyphonic pitch/CV section to make it controllable from a guitar. It had a projected end-user price of $20,000 (around £50,000 at today's prices). Just two prototypes were built, and Philip Dodds, Vice-President of Engineering at ARP, has since gone on record stating that Pearlman's failure analysis showed these units had a mean time between failures of just two hours.
By 1977 the company was developing two different Centaurs: the original Centaur VI, and a simplified keyboard-based version proposed by Dodds. The keyboard version side-stepped the apparently unsolvable technical nightmare the pitch/CV conversion had become, and seemed to have a better chance of appearing as a commercial product. Eventually, the development of the keyboard version was cancelled, and the company re-focused its efforts on the guitar synth. However, ARP still proved unable to solve the problems plaguing it, so some of the Centaur's concepts were split off to develop the Avatar.
In a sense the Quadra, like the Avatar, can be seen as an attempt to recycle ideas from the stranded Centaur project as the concept of "many synths in a box" seems to have been derived from the Centaur polyphonic/lead/bass synth project.

Miscellaneous

One French site referred to the synth as ‘un polyphonique modulaire’, but judging from the photos I’ve seen, this does not seem likely (anyone have additional info on this?)
By most accounts, there were only two prototypes made of the Centaur VI. Since the two photos posted on the previous Centaur thread showed two distinctly different designs, I think it is safe to presume that one of them was Dodds’ Keyboard version, and the other Friend’s guitar synth version.
I also found this little snippet of information about the filter used in the Centaur VI: ‘The 4109 is the filter used in the Centaur prototype. It is a VC state variable filter with low pass, high pass, bandpass and notch outputs, It uses the same basic filter section as the 4075 and 4072 filters and has voltage controlled resonance too.’
According to Philip Dodds there were 115 printed circuit boards in the Centaur VI. (Hence the outrageous projected production costs I take it)

I also found a page where, for a small sum of money, you can download the PDF version of a lecture on ‘An Integrated Guitar Synthesizer for Live Performance’ (that’s the Avatar, folks) given by David Friend in 1977:

http://www.aes.org/e-lib/browse.cfm?elib=3065

Someone asked about the whereabouts of the gentleman leaning against the keyboard version of the Centaur VI. Here’s a link to his homepage:

http://www.syntronics.us/

Apparently the photo is a tongue-in-cheek parody of the famous photo of Pete Townshend leaning against a 2600!

That’s all I have at the moment.

Jexus · Post by **Jexus** » Sat Dec 08, 2007 1:02 pm

once a Mod locks up a thread, it dies

gfriden · Post by **gfriden** » Sun Dec 09, 2007 12:21 am

Well, dead thread or not, here's the links to a couple of cool pics of the guitar-synth version of the Centaur VI (I think that was the main purpose behind the original thread, no?):

http://www.alt-mode.com/AHNE2004/image003.htm

http://www.alt-mode.com/AHNE2004/image004.htm

http://www.alt-mode.com/AHNE2004/image005.htm

http://www.alt-mode.com/AHNE2004/ARP_Guitar_synth.JPG

http://www.alt-mode.com/AHNE2004/ARP_Gu ... h_rear.JPG

Enjoy! 8)

JJQ · Post by **JJQ** » Mon Dec 10, 2007 1:06 pm

It looks so cool. And the name and rarity gives it an mythological feeling.

Has therer ever been any sound or music recorded with it?? Who owns the one in the pictures?

Mvh
Jesper

gfriden · Post by **gfriden** » Mon Dec 10, 2007 1:58 pm

In the previous thread on the Centaur, maindeglorie said he knew the owner of the sole prototype guitar-synth version of the Centaur and that this person might also be the owner of the only keyboard prototype. I have no idea at all if either worked well enough for any recordings to take place, but if they had, they would have been test recordings only, hardly intended for a commercial release. As far as I know, no famous musician ever owned one of these prototypes, unlike (for instance) Keith Emerson in the case of the Moog Apollo.

pricklyrobot · Post by **pricklyrobot** » Tue Dec 11, 2007 5:16 am

I wonder if ARP had survived and this project had been a success, would there have been other mythological monster named synths? I'd love to have seen the ARP Manticore, or the ARP Chimera, ARP Kraken, ARP Basilisk...

maindeglorie · Post by **maindeglorie** » Tue Dec 11, 2007 6:29 am

Yep, that "guitar synthesizer" prototype that I know of resides in Massachusetts, the home of ARP. I should mention to him that there's a thread about this. Actually, he should let me borrow it, since he has my CS-40M!

Will never happen.

Also, the ARP Kraken and Basilisk would be freakin' awesome!