960 Sequencer reissue

System 55 • System 35 • Model 15
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ProspectHillMusic
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Joined: Mon Jan 09, 2023 4:47 pm

960 Sequencer reissue

Post by ProspectHillMusic » Sun Feb 12, 2023 12:04 pm

I recently bought a new Sequencer Complement B. Others have posted on this forum on the build quality of Moog's current modular products and I thought that I'd add a few comments of my own here.

With the exception of the use of panel pots that were made by Alpha I think the overall construction is quite good. I have seen previous comments on the use of Alpha pots and I tend to agree that unsealed pots are maybe not the best choice but it is possible that the legacy sealed panel pots such as those that were made by Allen Bradley, Ohmite, and Clarostat are no longer available and Alpha is now the only choice. I did a quick search and found that sealed pots are still being made but there are far less options for ohmic values and more importantly, taper. For example, I found 1 megohm pots but only with a linear taper, I couldn't find audio taper pots in that value. This would be a major issue if these were used in a 911 envelope generator for example, use of a linear taper instead of an audio taper would throw off the front panel markings for rise and decay time.

Before receiving the 960 I had wondered what Moog had done about the long obsolete RTL logic chips that were used in the original 1960s design. I remember reading about how Gene Stopp had scrounged around to find enough RTL chips for the building of the Emerson modular clones in 2014 and I was curious if Moog had continued to use RTL in the current products but I was glad to see that they didn't do so. The main logic board in the 960 has been completely redesigned using 4000 series CMOS running at 5 volts supplied by a 7805 voltage regulator. This is exactly what I would have done had I been in charge of this product at Moog. The 961 and 962 were done differently though, the original PCB layouts were reused without modification, 4000 series CMOS was again used but the different pinouts were accommodated by the use of small daughter boards that each held a CMOS chip and in turn plugged into the socket where the RTL chip would have been. I'm not sure why this was done, it would seem to me that altering the original board layouts for CMOS pinouts wouldn't have been any more difficult than making a bunch of daughter boards but that's what they did.

The walnut cabinet looks good and matches the appearance and construction of my '70s vintage cabinets well.Image
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analogmonster
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Re: 960 Sequencer reissue

Post by analogmonster » Mon Feb 13, 2023 6:11 am

ProspectHillMusic wrote: Sun Feb 12, 2023 12:04 pm I recently bought a new Sequencer Complement B.
... it would seem to me that altering the original board layouts for CMOS pinouts wouldn't have been any more difficult than making a bunch of daughter boards but that's what they did.
That is a very good question. Which lets pop up some more philosophical questions in my opinion.
If you cut a Moog Modular into generic heaps or slices there are aspects which make sense to be reissued and aspects which absolutely don't make any sense.

I understood that there was a reissue of every technology forming the sound, meaning VCOs (the waveshaper sections) and filters (which are responsible for the Moog sound), and for the purists the passive mixer / control panel circuits with the original noise affected transistors.

But reissuing control logic???

A friend cloned the original 960. He bought original boards. It took him tons of money and time to obtain the original ICs for these boards, to do some logical operations which do not have any influence on any sound like AND, OR, NOT, FLIP FLOP, MONOFLOP etc. He built two of them, but can use only one at a time, as one important IC is still missing. And as he used the original TTLs, these 960 have a current consumption like a garage or car repair shop. The power supply of my Moog System 55 Clone decided to retire when I added only one of the 960 to my system for test purposes.

Anyway, (I know I get on people's nerves with that) I decided to create an own clone of the 960 and replaced the IC grave of the original circuit with a µcontroller solution, so I developed a much simpler board with a fractional amount of current consumption and much more sequencer functionality (ratcheting, 16 x 1, 24 x 1, MIDI capabilities, a complete overview and YouTube demos can be found at http://www.analog-monster.de/mmt960_en.html):
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I compared the haptics / human interface of my clone and the original (clone) in its behavior and could not find any difference, so consumer market oriented product policy is fine of course, but selling expensive invisible old fashioned technology in the background without any sound influence or benefit at all I really don't understand.

ProspectHillMusic
Posts: 12
Joined: Mon Jan 09, 2023 4:47 pm

Re: 960 Sequencer reissue

Post by ProspectHillMusic » Mon Feb 13, 2023 1:32 pm

I completely agree on your thoughts regarding the reissue of control voltage circuitry. An argument can be made about keeping the design of signal generating and signal processing circuity exactly the same as the original as it could theoretically affect the sound of the instrument, but control circuitry, assuming that it functions the same as the original design, will not affect the sound in any way. A while back I needed another envelope generator and so I built one, but rather than using the '60s vintage all discrete design that Moog used for the 911, I designed and built a functionally equivalent envelope generator that used CMOS analog gates and digital logic chips instead. That design used far fewer parts and consumed less power but works exactly the same as the original.

Your microcontroller based 960 clone looks like an elegant solution that has greater functionality than the original did.

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