Recursive Machine Build Thread

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Jonachi
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Recursive Machine Build Thread

Post by Jonachi » Sat Aug 22, 2020 11:24 am

Can’t beleive this one doesn’t have its own thread yet.

I just love how this sounds, high quality build as always from Zthee.



And




I’ve built it and absolutely love it!

More info here (he still have some kits available)

https://thehumancomparator.net/rm.html

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SkoPe
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Re: Recursive Machine Build Thread

Post by SkoPe » Mon Aug 24, 2020 3:56 am

I want to build one, unfortunately some Mouser parts are out of stock until mid September.
Also don’t know where to source the Song Huei pots with the short shaft, those are also out of stock @Thonk.

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EATyourGUITAR
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Re: Recursive Machine Build Thread

Post by EATyourGUITAR » Mon Aug 24, 2020 7:59 am

SkoPe wrote:
Mon Aug 24, 2020 3:56 am
I want to build one, unfortunately some Mouser parts are out of stock until mid September.
Also don’t know where to source the Song Huei pots with the short shaft, those are also out of stock @Thonk.
if mouser is out then everyone is out. everything was shut down. no new parts being made in the philipines, costa rica during covid. this is where the september october november dates come from.
WWW.EATYOURGUITAR.COM <---- MY DIY STUFF

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Jonachi
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Re: Recursive Machine Build Thread

Post by Jonachi » Tue Aug 25, 2020 11:05 am

Mid september is really soon though. I actuslly had the switch sent out to me ahead of time!

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myecholalia
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Re: Recursive Machine Build Thread

Post by myecholalia » Mon Sep 21, 2020 6:10 am

Any builders here willing to build one for me? What's a reasonable price for that?

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Re: Recursive Machine Build Thread

Post by jochem » Mon Sep 21, 2020 10:05 am

SkoPe wrote:
Mon Aug 24, 2020 3:56 am
I want to build one, unfortunately some Mouser parts are out of stock until mid September.
Also don’t know where to source the Song Huei pots with the short shaft, those are also out of stock @Thonk.
Banzai has that brand: https://www.banzaimusic.com/song-huei/

I saw this kit before, but the interface looks too dense for me.

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Re: Recursive Machine Build Thread

Post by Jonachi » Sat Sep 26, 2020 9:28 am

This happened!


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Re: Recursive Machine Build Thread

Post by four_corners » Sun Sep 27, 2020 8:22 pm

I know they are sold out right now, but does anyone know the price for the PCB kit? I hate when something that is out of stock doesn't even show the price...

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Heavy Metal Kid
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Re: Recursive Machine Build Thread

Post by Heavy Metal Kid » Mon Sep 28, 2020 1:56 am

The first batch was 799,- SEK plus shipping and tax.

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dankalmanson
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Re: Recursive Machine Build Thread

Post by dankalmanson » Mon Sep 28, 2020 5:06 pm

I'm curious about the SMD caps on the backside. On all the images I can see of a built RM they are absent as well as a lack of mention in the build doc but they exist on the mouser order. I did an awfully ugly job soldering them in but they exist on my board. :despair:

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Re: Recursive Machine Build Thread

Post by cat_abyss » Wed Sep 30, 2020 1:28 am

So i need to, eventually when things are for sale again, get PCB's from THC, the mouser cart with (almost) all the parts, and then "You'll also need 2 x PT2399, 1 x BDTR-2H, and 33 x potentiometers (Song Huei short, 100k lin)" i guess because they're not at mouser? Is this the kinda game where i should grab things as soon as i see them available?

Also can i interchange the different lenghts of BDTR-2H...

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Re: Recursive Machine Build Thread

Post by dankalmanson » Wed Sep 30, 2020 12:59 pm

All of those are easy to find. I got my pots from synthcube, the pt2399's from small bear and the BDTR-2H from a seller on ebay. It was painless to source them.

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Re: Recursive Machine Build Thread

Post by bohoio » Sun Oct 04, 2020 5:31 am

Hi all

I'm almost halfway through the build and am currently doing all SMD parts.

One issue though, the most recent mouser cart on the site calls for the following.

1 x 71-CRCW08050000Z0ECC (Thick Film Resistors - SMD 1/8Watt 0ohms Commercial Use)

There is no 10k SMD part in the latest mouser cart even though it's in the BOM, so I'm assuming the above item is the replacement for it? If so, is it for the front PCB filter circuit with the SMD pad underneath the Q pot labelled 10K? I did look at the circuit diagrams but couldn't find R36 for the life of me! Seems to be a large disparity between the two values though :|

Also all parts are available for the most recent mouser cart form the site, just need to change the package type for a few resistors and a few other minor alternative. The power switch is available in white instead of grey etc. Happy to share cart if anyone needs it.

Cheers

Boh

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Re: Recursive Machine Build Thread

Post by dankalmanson » Mon Oct 05, 2020 11:27 pm

I'm having some difficulty. I powered it up for the first time a few hours ago and have reflown everything. Both of my oscillators are not working. Everything else seems to be fine. I'm getting a really strong hiss. I'm assuming this has something to do with the power but i'm really unsure and confused.

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Re: Recursive Machine Build Thread

Post by dankalmanson » Tue Oct 06, 2020 3:16 am

So I read up more on the pre patching of the manual and the hissing I was getting was actually some tasty feedback. I'm pretty much up and running except I cannot change the freq of osc !. I'll try and trace it back tomorrow but i'm having fun right now.

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Re: Recursive Machine Build Thread

Post by Hovercraft » Thu Oct 08, 2020 2:22 pm

bohoio wrote:
Sun Oct 04, 2020 5:31 am
Hi all

I'm almost halfway through the build and am currently doing all SMD parts.

One issue though, the most recent mouser cart on the site calls for the following.

1 x 71-CRCW08050000Z0ECC (Thick Film Resistors - SMD 1/8Watt 0ohms Commercial Use)

There is no 10k SMD part in the latest mouser cart even though it's in the BOM, so I'm assuming the above item is the replacement for it? If so, is it for the front PCB filter circuit with the SMD pad underneath the Q pot labelled 10K? I did look at the circuit diagrams but couldn't find R36 for the life of me! Seems to be a large disparity between the two values though :|

Also all parts are available for the most recent mouser cart form the site, just need to change the package type for a few resistors and a few other minor alternative. The power switch is available in white instead of grey etc. Happy to share cart if anyone needs it.

Cheers

Boh
Yes, 10K SMD resistor is shown on the pcb under the filter's Q pot, but you should use the 0K bridge resistor in it's place. THC made the change, so the filter will self-oscillate--and believe me, you want to do the same.

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Re: Recursive Machine Build Thread

Post by Heavy Metal Kid » Thu Oct 08, 2020 2:33 pm

Hovercraft wrote:
Thu Oct 08, 2020 2:22 pm
Yes, 10K SMD resistor is shown on the pcb under the filter's Q pot, but you should use the 0K bridge resistor in it's place. THC made the change, so the filter will self-oscillate--and believe me, you want to do the same.
Just a wire (resistor leg) will do?

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Re: Recursive Machine Build Thread

Post by Hovercraft » Thu Oct 08, 2020 6:17 pm

Heavy Metal Kid wrote:
Thu Oct 08, 2020 2:33 pm
Hovercraft wrote:
Thu Oct 08, 2020 2:22 pm
Yes, 10K SMD resistor is shown on the pcb under the filter's Q pot, but you should use the 0K bridge resistor in it's place. THC made the change, so the filter will self-oscillate--and believe me, you want to do the same.
Just a wire (resistor leg) will do?
Yup--you just have to bridge the two pads.

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Re: Recursive Machine Build Thread

Post by Hovercraft » Thu Oct 08, 2020 6:31 pm

It's not in the BOM, but I'd recommend A100 (log) pots for the mixer. I used the longer shaft Song Huei A100 pots, so I have a nice audio taper, and it's a little easier to mix. Sure wish THC had specced a USB jack for the power instead of an oddball size barrel jack--since it's 5V. I'll probably put in one myself. Powering off of a phone battery makes more sense than the badly-placed AA batteries.

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Re: Recursive Machine Build Thread

Post by Heavy Metal Kid » Fri Oct 09, 2020 1:27 am

Hovercraft wrote:
Thu Oct 08, 2020 6:17 pm
Yup--you just have to bridge the two pads.
Cheers!

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Re: Recursive Machine Build Thread

Post by Heavy Metal Kid » Fri Oct 09, 2020 1:28 am

Hovercraft wrote:
Thu Oct 08, 2020 6:31 pm
It's not in the BOM, but I'd recommend A100 (log) pots for the mixer.
Yeah, I got the audio pots for the mixer. Building it now, will have it finished in a few days.

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Re: Recursive Machine Build Thread

Post by Peake » Fri Oct 09, 2020 10:27 am

It's worth trying log pots for the LFO rate controls, your mileage may vary. It seemed hard to dial in slow LFO rates with the linear pots but by the time I put in log pots I couldn't remember the previous response and didn't do a comparison. (Built one for someone and don't have it here to check.)
This is not the place I'd imagined it to be.

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Re: Recursive Machine Build Thread

Post by Hovercraft » Fri Oct 09, 2020 12:37 pm

Peake wrote:
Fri Oct 09, 2020 10:27 am
It's worth trying log pots for the LFO rate controls, your mileage may vary. It seemed hard to dial in slow LFO rates with the linear pots but by the time I put in log pots I couldn't remember the previous response and didn't do a comparison. (Built one for someone and don't have it here to check.)
You can also make the LFO circuits slower by using bigger caps in the circuits. I was tempted to try this off the bat, but decided to use the RM for a few weeks before deciding. I'll likely slow down one of the LFO's--I don't need both to be able to go up to audio rate.

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Re: Recursive Machine Build Thread

Post by Peake » Fri Oct 09, 2020 1:05 pm

Right! A drone machine needs at least one slow LFO.
This is not the place I'd imagined it to be.

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Re: Recursive Machine Build Thread

Post by Peake » Fri Oct 09, 2020 11:04 pm

Not sure if Jon updated the manual but he recommended to me, after the last indicated manual revision date, to increase the gain of the wet reverb by changing the 39K in the top section of the reverb (between the 1K and 10K) to 10K or less.
This is not the place I'd imagined it to be.

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