ARP 1601 clone Build Thread

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Kipling
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Re: ARP 1601 clone Build Thread

Post by Kipling » Fri Apr 24, 2020 2:56 am

It is possible to mod the board to add pots, but they’d be an awkward fit and It would involve cutting tracks on a 4-layer board which I would thoroughly discourage. The inner layer on the component side is +15V so any inadvertent short between a cut track end on the top layer and +15V (or to 0V if the relevant track is on the bottom side) could be catastrophic.

Far better in my opinion to make up some attenuating leads as per my earlier post.

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Re: ARP 1601 clone Build Thread

Post by Sammus » Mon May 04, 2020 2:34 am

I was thinking of adding the divider to my v3 (will have to figure out labelling) - does anywhere sell the pcb separately? I was thinking of getting some made but only need 1 :) I'm in Australia, in case anyone here has some spares :D

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Re: ARP 1601 clone Build Thread

Post by KSS » Mon May 04, 2020 6:25 pm

How about just make it up on pad-per-hole, stripboard or perf?

Trust yourself. If you can follow the lines in a schematic, and use a colored marker to show what you've already done, you can probably do this.
You don't have to understand the schematic completely to be successful. You do need to know what the component parts are.

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Re: ARP 1601 clone Build Thread

Post by Sammus » Tue May 05, 2020 2:25 am

yeah I was thinking that as I typed it! I have plenty of strip board kicking around, I've made some super simple stuff on strip before, this looks like a good next step.

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Re: ARP 1601 clone Build Thread

Post by synthcube » Mon Jun 22, 2020 4:57 pm

Update as of 22 june 2020-- we now have the new run of panels and boats in stock. Panels now have the label 'PWR' added in the right spot. Boats have been modified to include captive #10 nuts X 12 for mounting the wood cheeks. PCB sets now shipping with v6 + the Divider PCB
facebook: https://www.facebook.com/2SynthCube

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music from outer space euro smt: www.mfoseuro.com

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Re: ARP 1601 clone Build Thread

Post by retokid » Mon Jul 13, 2020 10:31 am

R210/R211 Values

I am gently building my 1601 (rev 5) and was wondering about R210/R211 values one is 10k the other 100k, this traces back to the original service manual. Both resistors are however used at the same place in channel A and B quantized output memory. There is obviously an error, although I guess it makes no significant difference otherwise someone would already have noticed. Nevertheless, anybody has a clear idea of what is the right/better value ?

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Re: ARP 1601 clone Build Thread

Post by Kipling » Mon Jul 13, 2020 10:47 am

retokid wrote:
Mon Jul 13, 2020 10:31 am
R210/R211 Values

I am gently building my 1601 (rev 5) and was wondering about R210/R211 values one is 10k the other 100k, this traces back to the original service manual. Both resistors are however used at the same place in channel A and B quantized output memory. There is obviously an error, although I guess it makes no significant difference otherwise someone would already have noticed. Nevertheless, anybody has a clear idea of what is the right/better value ?
Yes I spotted that very early on. It’s not helped by the fact that the original ARP PCB was incorrectly marked for one of those two and another one (which if memory serves me correctly is also 100k). I recall mentioning it quite near the top of this thread some years ago now. In my opinion I’d go for 100k for both, but in reality I don’t think it matters that much.

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Re: ARP 1601 clone Build Thread

Post by Robber40 » Mon Jul 13, 2020 6:02 pm

I'm facing some issues with my build.
  • The sequencer works but I'm getting no signal on Gate Bus 1 and Gate Bus 3. Start, Stop, Reset and signal via Gate Bus 2 works fine.
  • The Skip/Reset function while the sequencer is running (in combination with the Gate select switch(es)) does not work.
  • Section 4 from the service manual: I'm getting no signal at TP16 and TP17. All other TPs give the correct signal.
  • Section 5 from the service manual: Turning R26 does not change the waveform.
Now I hope that someone tells me that all is related to each other and that Icxxx is most likely defective :-D

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Re: ARP 1601 clone Build Thread

Post by Kipling » Tue Jul 14, 2020 2:30 pm

Robber40 wrote:
Mon Jul 13, 2020 6:02 pm
I'm facing some issues with my build.
Now I hope that someone tells me that all is related to each other and that Icxxx is most likely defective :-D
I think there’s more than one issue. I’ll give you my more detailed thoughts tomorrow when I can get to my PC.

In the meantime I presume you have the slide switches for at least some of the 16 positions set to Gate Bus 1 and/or Gate Bus 3 when the sequencer is running. If so and Gate Bus 1 is still not outputting a gate signal, do you get anything out of the Clocked Gate 1 Out socket?

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Re: ARP 1601 clone Build Thread

Post by Robber40 » Tue Jul 14, 2020 3:12 pm

Kipling wrote:
Tue Jul 14, 2020 2:30 pm
Robber40 wrote:
Mon Jul 13, 2020 6:02 pm
I'm facing some issues with my build.
Now I hope that someone tells me that all is related to each other and that Icxxx is most likely defective :-D
I think there’s more than one issue. I’ll give you my more detailed thoughts tomorrow when I can get to my PC.

In the meantime I presume you have the slide switches for at least some of the 16 positions set to Gate Bus 1 and/or Gate Bus 3 when the sequencer is running. If so and Gate Bus 1 is still not outputting a gate signal, do you get anything out of the Clocked Gate 1 Out socket?
Thanks a lot for the quick reply. I've huge respect for what you've developed with the 1601 re-creation and highly appreciate how much effort you spend in helping others. After a lot of re-soldering and searching for the problem by swaping ICs, I found at least one problem. The damm SMD chip Z4. (I'm to old for this small parts :-D ) I was already suspecting this. After removing it, cleaning the pads and soldering it again, the skip and reset during a sequence is working. I'm also getting now a signal on all 3 Gate outs. I have to do the calibration tomorrow and will check if I'm also getting now all signals at the TPs correctly.

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Re: ARP 1601 clone Build Thread

Post by Kipling » Tue Jul 14, 2020 4:07 pm

Robber40 wrote:
Tue Jul 14, 2020 3:12 pm
Kipling wrote:
Tue Jul 14, 2020 2:30 pm
Robber40 wrote:
Mon Jul 13, 2020 6:02 pm
I'm facing some issues with my build.
Now I hope that someone tells me that all is related to each other and that Icxxx is most likely defective :-D
I think there’s more than one issue. I’ll give you my more detailed thoughts tomorrow when I can get to my PC.

In the meantime I presume you have the slide switches for at least some of the 16 positions set to Gate Bus 1 and/or Gate Bus 3 when the sequencer is running. If so and Gate Bus 1 is still not outputting a gate signal, do you get anything out of the Clocked Gate 1 Out socket?
Thanks a lot for the quick reply. I've huge respect for what you've developed with the 1601 re-creation and highly appreciate how much effort you spend in helping others. After a lot of re-soldering and searching for the problem by swaping ICs, I found at least one problem. The damm SMD chip Z4. (I'm to old for this small parts :-D ) I was already suspecting this. After removing it, cleaning the pads and soldering it again, the skip and reset during a sequence is working. I'm also getting now a signal on all 3 Gate outs. I have to do the calibration tomorrow and will check if I'm also getting now all signals at the TPs correctly.
Thanks, just doing what I love.

Z4 was one of those I had suspected for the gate issue, along with Z17, but it would seem that Z17 is fine.

For the TP16/17 issue the obvious choice would be Z25, unless something is dragging two of the outputs down, or it’s not being clocked or reset properly. However if TP19 & 21 look correct then that should rule out the clock/reset so Z25 looks the main suspect.

R26 also feeds into part of Z4 so hopefully you’ve cured that already by resoldering Z4.

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Re: ARP 1601 clone Build Thread

Post by Robber40 » Wed Jul 15, 2020 2:24 pm

It's all working now and TPs give all the correct signal. It seems to be that it was really all related to the Z4. Will post some videos on YouTube soon. Hope to finish my Keyboard for the TTSH soon as well.

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Re: ARP 1601 clone Build Thread

Post by Kipling » Wed Jul 15, 2020 3:18 pm

Robber40 wrote:
Wed Jul 15, 2020 2:24 pm
It's all working now and TPs give all the correct signal. It seems to be that it was really all related to the Z4. Will post some videos on YouTube soon. Hope to finish my Keyboard for the TTSH soon as well.
:tu:

Your keyboard looks promising. I like the sound of a ribbon controller. I saw it on one of the Facebook groups the other day but can’t remember which one.

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Re: ARP 1601 clone Build Thread

Post by Robber40 » Sun Jul 19, 2020 10:26 am

Done...for now. Everything up and running. Next will be the Keyboard :-)
IMG_0317-2.jpg
IMG_0316-2.jpg
IMG_0284.jpeg
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Re: ARP 1601 clone Build Thread

Post by funkytransport » Tue Jul 21, 2020 7:46 am

Hello there.. I just picked up a Rev 3 1601 PCB and Panel...
I've had a skim through this thread but can't seem to find the Rev 3 BOM? Is there one out there? or should I work off rev 2 or rev 4?
Thanks for any help

Iain

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Re: ARP 1601 clone Build Thread

Post by Kipling » Tue Jul 21, 2020 8:08 am

funkytransport wrote:
Tue Jul 21, 2020 7:46 am
Hello there.. I just picked up a Rev 3 1601 PCB and Panel...
I've had a skim through this thread but can't seem to find the Rev 3 BOM? Is there one out there? or should I work off rev 2 or rev 4?
Thanks for any help

Iain
Use the Rev 2 BOM, and source the non-Mouser parts elsewhere, notably the LM301AN, MC14528B and two LM3046, all in DIP (not SMT).

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Re: ARP 1601 clone Build Thread

Post by funkytransport » Tue Jul 21, 2020 8:33 am

Thank you Kipling :)

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Re: ARP 1601 clone Build Thread

Post by Kipling » Tue Jul 21, 2020 9:38 am

funkytransport wrote:
Tue Jul 21, 2020 8:33 am
Thank you Kipling :)
:tu:

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Re: ARP 1601 clone Build Thread

Post by maxplower » Sat Aug 08, 2020 8:36 pm

ANOTHER EDIT: The full PCB Kit incl parts from synthcube is far cheaper than ordering the parts from mouser separately:

full kit 499 USD (626.80AUD)
vs.
synthcube pcb panel alone 249 USD (347AUD)
Parts from mouser $350 AUD (not including other places needed to order from which would ramp up postage cost to like $20 per component)


EDIT: Just decided to create a new mousie BOM :party: This doesn't include the clock divider which I just realised I will also need to sort out
https://au.mouser.com/ProjectManager/Pr ... =4f5c857d4

@Kippling, do you think it would be possible for someone who is crazy to get that MC14528 SMT from mouser into use? Or will the DIP have to be ordered somewhere else? I just can't be bothered finding a supplier to order a single component from...

Below is what was missing from mouser and will need to be sourced from somewhere else:
FE-M3-.5-6PAN-BLK -these are panel screws
LM301AN as above, kipling indicates not supplied by mouser
CA3046M -NOT AVAILABLE apearing as CA3046 on mouser sheet AND NOT AVAILABLE
WQP518MA-BM -These are the Qinpu 3.5mm jacks, can be ordered through synthcube.com
B07SMQC5TH -Keyboard buttons. Looks like I can get them on amazon

MC14528 is not DIP from mouser. I guess it needs to be ordered somewhere else. nevertheless, I still have it in the mouser cart as it came up!

Sidenote:
Why does synthcube not have the BOM on their product page...?
https://synthcube.com/cart/j.m.%20logan ... uencer-diy

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Re: ARP 1601 clone Build Thread

Post by Kipling » Sun Aug 09, 2020 3:07 am

maxplower wrote:
Sat Aug 08, 2020 8:36 pm
@Kippling, do you think it would be possible for someone who is crazy to get that MC14528 SMT from mouser into use? Or will the DIP have to be ordered somewhere else? I just can't be bothered finding a supplier to order a single component from...

Below is what was missing from mouser and will need to be sourced from somewhere else:
FE-M3-.5-6PAN-BLK -these are panel screws
LM301AN as above, kipling indicates not supplied by mouser
CA3046M -NOT AVAILABLE apearing as CA3046 on mouser sheet AND NOT AVAILABLE
WQP518MA-BM -These are the Qinpu 3.5mm jacks, can be ordered through synthcube.com
B07SMQC5TH -Keyboard buttons. Looks like I can get them on amazon

MC14528 is not DIP from mouser. I guess it needs to be ordered somewhere else. nevertheless, I still have it in the mouser cart as it came up!
Unless you have an older Rev 3 or earlier PCB, the MC14528 required is SMT, not DIP. The same goes for the CA/LM3046, except that it has since been discontinued in SMT form too, so has to be obtained wherever possible. Note: The RF version of the 3046 (968-HFA3046BZ) *may* work, but it is untested and quite expensive.

The LM301AN is also now discontinued in DIP (all PCB versions to date require DIP for that one) so has to be obtained elsewhere. However I note that Mouser can supply an SMT version 863-LM301ADR2G which I hadn't realised existed previously, so I may update the PCB again to accommodate that. If you are feeling particularly rich you could always use the TO99-8 can version 926-LM301AH and fan out the leads to fit a DIP layout.

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Re: ARP 1601 clone Build Thread

Post by Altitude909 » Sun Aug 09, 2020 9:05 am

^
alfa has a 3046 now in both dip and SOIC

http://www.alfarzpp.lv/eng/sc/AS3046.pdf

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Re: ARP 1601 clone Build Thread

Post by LED-man » Sun Aug 09, 2020 9:28 am

LM201 in SOIC Format with an adapter can be used as direct replacement for the LM301
################################
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Re: ARP 1601 clone Build Thread

Post by Kipling » Sun Aug 09, 2020 9:52 am

It will be easy to change the PCB to soic for this chip.

EDIT: already done!

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Re: ARP 1601 clone Build Thread

Post by Kipling » Mon Aug 10, 2020 7:20 am

Altitude909 wrote:
Sun Aug 09, 2020 9:05 am
^
alfa has a 3046 now in both dip and SOIC
Thanks for making that known.

I see that Thonk (UK) now stocks both versions https://www.thonk.co.uk/shop/alpha-as-series-ic-chips/ and SynthCube stock the DIP14 version https://synthcube.com/cart/alfa-rpar-synth-ics. I presume there are other suppliers too.

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Re: ARP 1601 clone Build Thread

Post by uwe » Sun Aug 23, 2020 1:46 am

i'm building this to go with my ttsh. thanks for all the hard work you guys poured into this! i finally sourced all the ICs and finished the build.

the quantizer is giving me some trouble. i have the sequencer stopped and step 1 active. the quantizer A output range is 0-2V, but bounces around quite a bit when i move the slider. it looks like it dips to 0V and then comes back to where the slider is set. it also changes notes without slider movement irregularly every 20 clock cycles or so. the note change seems to happen only when the slider is set <50%. the unquantized output goes from 0-10V.

quantizer output B has a different issue. the slider at 100% gives me 2V and approaches 1V when i lower it, but it suddenly drops to 0V when i reach 50%.

the test points around the scanner are a bit odd. TP13, 14, 15, 16 and 17 have a +1V offset on my scope that looks really odd. sort of ADSR shaped.

thought i'd post here before i start replacing random chips.

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