Project PRO2021 - A Pro-One keyboard synth

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Altitude909
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Altitude909 » Wed Feb 12, 2020 4:35 pm

Kevin Mitchell wrote:
Wed Feb 12, 2020 2:28 pm
:lol: :lol: :lol: perfect.

I'm going to hit the hardware store. If they stock the thinnest walled 1/4 brass tubing I should be in business 👍

-KM
dont bother, i've looked at all available stock sizes and there isnt anything there, you either have to have it custom drawn or ream it out (I did that for a bit, it sucked). Youre talking about something with a wall thickness of 0.006", even if you could find a tube that size, good luck cutting it.

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Kevin Mitchell
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Wed Feb 12, 2020 6:38 pm

Edit; never mind lol
Last edited by Kevin Mitchell on Wed Feb 12, 2020 7:02 pm, edited 1 time in total.

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Altitude909
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Altitude909 » Wed Feb 12, 2020 6:51 pm

Once you make up the diameter difference, thats pretty much it, you dont have to deal with the D portion of it

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Kevin Mitchell
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Wed Feb 12, 2020 6:58 pm

Altitude909 wrote:
Wed Feb 12, 2020 6:51 pm
Once you make up the diameter difference, thats pretty much it, you dont have to deal with the D portion of it
Duh :hmm:

The pot shafts have a little play I thought it was still not centered.

The straw method is verified lol. Though not perfect - it's much better. Great tip! Also - rotaries don’t seem to need them.

-KM
Last edited by Kevin Mitchell on Thu Feb 13, 2020 12:00 pm, edited 1 time in total.

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Thu Feb 13, 2020 11:59 am

Unintentional post...

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by synthcube » Fri Feb 14, 2020 1:39 pm

we have these awesome little brass bushings that adapt a 6mm shaft to 6.35mm -- mostly used for people who have knurled shaft 6mm pots and want to use round shaft 6.35mm knobs
facebook: https://www.facebook.com/2SynthCube

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MOTM DIY Analog Synthesizers: www.motmsynthesizers.com
music from outer space euro smt: www.mfoseuro.com

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by gslug » Fri Feb 21, 2020 9:33 am

Mine has arrived. Looks great, but sadly USPS/Parcelforce don't seem to have treated it well - keybed and top case damaged, despite good packaging. :waah:
One day I'll get an avatar!

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Fri Feb 21, 2020 5:23 pm

Received the rest of the hardware today. All seems good!

Not sure if SC acknowledged my note on the keybed cable length. 8” will not reach and needs to be much longer to have it connected while the chassis is open for calibration.
No need to send me one.

Thanks for all the work on getting this thing situated.

-KM

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Sat Feb 22, 2020 5:53 pm

Awesome news on the hardware!

Re: the keyboard cable, i'll have to see where this 8" came from. I'm not sure I ever specifified a length on that, because on the 2 prototypes I built I used keybeds purchased from TechMechs synth and they came with the longer cable, which I believe is 50cm (~19"). I think there are only a couple or few choices of preterminated cables from Fatar though, so it will just be a matter of Synthcube getting the right ones next time.

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by gslug » Sat Feb 22, 2020 10:31 pm

Managed to bend back the deformed part of my top case (one of the end flanges), and Synthcube are sending me a new keybed, so all good! Haven't had a chance to check the hardware, but I think everything is there. My keyboard cable is short though.
One day I'll get an avatar!

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Mon Feb 24, 2020 10:09 am

Twas a long weekend :sb:
Current status - added more zip ties, eyed out keybed cable length. About 2' is perfect for how I have the chassis held open - it's being held up by the lower chassis, propped up by a book and leaning against the parts drawer/back wall.

First start up seems good! Power supply is golden. Though somehow I wired/soldered the power LED leads backwards. The micromatch connectors for the keybed cable should be in on Wednesday. In the meantime I think I'll hook up my keystep and see if this thing makes any noises.

YES I'M ON STEP ONE OF CALIBRATION :hail:

A couple minor correction for the build guide; Sent Devin a PM.

Updated with some build notes;
Other than a philips you'll need a T15 driver (for keybed screws) and a 3/32" hex driver (for end cheeks)

A crimping tool is necessary.
Even though the shielded cable is 26AWG the wires were a bit small and my crimping tool couldn't do it even though it can do 28-24AWG. I had to solder each wire to the terminals to ensure a good connection. Maybe my tool just sucks :lol:

I've found it best to not use the dust covers. SC was nice enough to send some plastic ones (4 short however) but the 3 position switches on the left tend to get stuck and push against each other rather than lap over each other. I already had the felt ones on hand and they seem to stretch and distort. The switches feel and operate better without them.

I'd screw on the keybed last (after end cheeks) since you may need room to hand adjust the clip-on nuts for the end cheeks. They can be a PITA and get pushed open if they aren't aligned correct. If they bend open you'll have to remove them and pinch them back snug with pliers.

-KM
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Last edited by Kevin Mitchell on Tue Feb 25, 2020 8:21 am, edited 12 times in total.

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Mon Feb 24, 2020 11:28 am

Awesome!

Hey Kevin, yes please send me the bugs in the build documentation and I'll get it fixed up!

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Mon Feb 24, 2020 3:09 pm

PM sent.
Also - in case MTG ever wonders where the smiley turbo CPU landed :lol:
Appreciate the small things.

Be back later in the week with a finished build. Or... you know :hmm:

-KM
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Tue Feb 25, 2020 11:26 am

Haha.. nice!

Grant is the man! The Turbo is great and without it I wouldn't have been able to pull off the project!

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Fri Feb 28, 2020 8:53 am

All calibrated and put together!!! Was probably one of the least painful tuning jobs I've had with a synth. This thing is mean 8-)

Maybe it's because I've been in the assembly game for a while or due to premeditating this build for months but I had no issues with this other than wiring the power LED backwards :hihi:
I'll call that a benchmark. Definitely a fun build. The most tedious part was the cable assemblies but with the build doc being so great every bit was a cake walk.

Demo soon :sb:

-KM

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Fri Feb 28, 2020 11:27 am

Hellllll yeah!

So glad you got her up and running. It really is a fun synth to play. You can get some straight nasty tones out of it, and the Fatar board has just the perfect feel for a synth IMO! :sb:

I do agree the chassis wiring is the biggest PITA. I've toyed with the idea of making a long, thin connector PCB that has the MIDIs, Audio, and CV jacks all on that board and then it would just connect up to the A&B boards with some ribbon cables.

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Tue Mar 10, 2020 7:10 am

Edit:
Was complaining about the filter attack not being responsive - could have just been that the sustain and cutoff needed to be dialed down.

Isn't learning fun :lol:

-KM

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Wed Mar 11, 2020 10:58 am

The settings lattitude on the CEM envelopes as used in the Pro-One are pretty large! Definitely if you're coming from a Moog or Arp, IMO, you have to be a little more thoughtful about adjusting them, but that is part of what makes some more interesting sounds possible! Have fun!

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by needspeed » Mon Mar 16, 2020 8:23 pm

I got a very large box from my dear friends as Synthcube. I got a Cloney just started I am so conflicted.......AHHHHHHHHH
To a never ending journey of exploring all noise that may or may not be music to someone or anyone.

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Tue Mar 17, 2020 12:07 pm

It's like Christmas over at your house eh!? :sb: :sb:

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by amonti » Sat Apr 18, 2020 5:24 am

It great to see Devin’s Pro2021 available at SynthCube - definitely the best kit I’ve ever made!

Now that I have some extra time at home, I’m trying to tackle something that’s always eluded me on my build - the “Noise” knob does not introduce any noise, but it does work somewhat when I patch in an external audio source (it’s not super-clear, but I do hear what I’m patching in). I just finished the following with to no avail: swapping input and output cables, making sure the TRS tip is shorted when there’s not input, tracing through all components around U107 and U108, re-seating the chips, reflowing the soldier around these areas, testing the resistors, caps, and diodes ensuring the proper voltages are flowing to the chips and components. Short of ordering new ICs, I’m not sure what the best approach should be at this point. I turned on my scope, but thought I’d check here first to see if anyone had the same issue.

Thanks in advance!

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by amonti » Sat Apr 18, 2020 10:24 pm

amonti wrote:
Sat Apr 18, 2020 5:24 am
It great to see Devin’s Pro2021 available at SynthCube - definitely the best kit I’ve ever made!

Now that I have some extra time at home, I’m trying to tackle something that’s always eluded me on my build - the “Noise” knob does not introduce any noise, but it does work somewhat when I patch in an external audio source (it’s not super-clear, but I do hear what I’m patching in). I just finished the following with to no avail: swapping input and output cables, making sure the TRS tip is shorted when there’s not input, tracing through all components around U107 and U108, re-seating the chips, reflowing the soldier around these areas, testing the resistors, caps, and diodes ensuring the proper voltages are flowing to the chips and components. Short of ordering new ICs, I’m not sure what the best approach should be at this point. I turned on my scope, but thought I’d check here first to see if anyone had the same issue.

Thanks in advance!
Never mind - found the i18n problem; I somehow managed to wire both the audio Molex connectors with crossed pinouts. Surprisingly, the output jack worked fine, but the input section wasn’t pleased. It’s nice to have noise, but (and a I may be imagining this) even at 0, I still think I hear a tiny bit of white that becomes far more apparent as you turn up the knob. May have to run a few tests and post what I find.

Thanks again

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by musicorchard » Thu Apr 23, 2020 10:58 pm

So quick question... is anyone else having trouble with the Micro-MaTch cable that connects the keyboard to the PCB? Mine appears to be about an inch too short and that's barely leaving any clearance to open the top panel to adjust trimmers. It really needs to be at least 12 inches in order to flip the top panel open to reach the trim pots for calibration. I'm having a lot of trouble finding a cable of that size. Any suggestions?

EDIT: As I tried to solve this issue on my own, I realized in my random parts bin that I have some extra pieces that were shipped to me from Synthcube in this kit. I received two 16p cables meant to link the two PCBs but were too short to do the job. Luckily, I was sent a second too short keyboard cable that I plan to splice onto the other to make things work. I'm a little bummed that this wasn't addressed as the kits were sent out, but I'm more than happy to problem solve and make it work! This cable is the last component to install before I can calibrate and make this beast roar!

Maybe I got a weird kit, but mine was missing a bunch of necessary components that were and were not listed on the Synthcube BOM. IE: missing - a 16p header socket, I only received 11 knobs (although I decided to buy the Jove knobs so I wouldn't have to trim the pots), a female 20p Micro-MaTch header, and an array of screws. It's all good in the long run since I had much of this on hand during my other builds. Once I complete the build I can document the exact pieces I was missing in case this is an issue across the board.

All the best and keep synthing! :sb:

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Kevin Mitchell » Mon Apr 27, 2020 1:46 pm

My note on the 8" keybed cable synthcube is supplying has been neglected several times - a few times on this thread and at least twice through email.
I have extra material so one can put together an appropriate length cable. If anyone in the states are desperate I can help or point you to the materials to assemble your own as I did.

2' was perfect for my assembly- might need more slack if you assemble like Devin did.
With 12", it'll do the job but good luck getting your hand and trim driver in there to tune the thing.

I'm curious to know if anyone used the switch covers included - I found them to be a PITA and did not use any.



I love the hell out of this synth.

-KM

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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Mon Apr 27, 2020 2:00 pm

musicorchard , how long is the 2nd keyboard cable? I thought I had gotten that sorted out with Synthcube.

Kevin did a great job of bringing up all the missing hardware from the first kits they put together, and I thought we were synched up now. It could be they just didn't get yours updated before sending it out. If you let SynthCube know the stuff you're missing, they should be able to provide it.

Oh, one final note, I finally, after like 5000 frustrating emails, was able to procure a last-time buy of the TO heat sinks used on the PSU board, so I am sitting on 50 of them. We should be good for the foreseeable future :).

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