Kassutronics VC Slope

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pugix
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Kassutronics VC Slope

Post by pugix » Thu Oct 08, 2020 2:36 pm

Richard
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Re: Kassutronics VC Slope

Post by appliancide » Thu Oct 08, 2020 2:52 pm

Cool trick to get an ADSR out of that circuit!

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Re: Kassutronics VC Slope

Post by pugix » Thu Oct 08, 2020 3:25 pm

appliancide wrote:
Thu Oct 08, 2020 2:52 pm
Cool trick to get an ADSR out of that circuit!
After Later Audio Tilt has this feature, too.

https://afterlateraudio.com/product/tilt/
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Re: Kassutronics VC Slope

Post by SphericalSound » Fri Oct 09, 2020 6:07 pm

With 2 of these you get almost a rampage/maths. In some cases it´s even more flexible as you get control of the four curves. Cool circuit

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Re: Kassutronics VC Slope

Post by BWBKc6VyUr » Mon Oct 12, 2020 7:24 am

Has anybody built one yet? I’m curious about the cost of parts, wonder what’s e.g. Mouser basket ballpark for a unit.
WTB:
Veils (pre-2020)
TipTop stackable cables

FS:
Arturia Beatstep Pro (white) - £150 + shipping
Antumbra 6MIX - £75 + shipping
Kassutronics Slope 2 - £110 + shipping

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Re: Kassutronics VC Slope

Post by Jarno » Mon Oct 12, 2020 9:14 am

Ordered 2 PCB's (despite having 4 VCS's already :D , one cannot have enough slope generators)
BWBKc6VyUr wrote:
Mon Oct 12, 2020 7:24 am
Has anybody built one yet? I’m curious about the cost of parts, wonder what’s e.g. Mouser basket ballpark for a unit.
Counting parts, and estimating piece part cost, 35 euro each-ish?
I grab most of the components from my mountain of stock, hoping to reduce it somewhat.

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Re: Kassutronics VC Slope

Post by BWBKc6VyUr » Thu Nov 05, 2020 5:59 am

Wooden front panels though?
WTB:
Veils (pre-2020)
TipTop stackable cables

FS:
Arturia Beatstep Pro (white) - £150 + shipping
Antumbra 6MIX - £75 + shipping
Kassutronics Slope 2 - £110 + shipping

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Re: Kassutronics VC Slope

Post by BWBKc6VyUr » Tue Nov 24, 2020 9:59 am

I'm building a couple of those right now. I just thought I'd highlight something that caught me off guard for the benefit of potential future builders.

Connectors J11 & J12 on the main PCB (both 6 pins) are positioned flush against each other:
Untitled.png
The BOM specifies two 6-pin sockets to match J11 & J12 on the back of the panel PCB, labelled J15 & J16, so that's what I ordered from Mouser. However, the positioning of J11 & J12 does not allow for the extra plastic at the side of each 6-pin socket (coloured in red above). I had to shave J15 & J16 to fit flush against each other in alignment with J11 & J12. Save yourself the headache and order a single 12-pin socket for J15 & J16 instead of two 6-pin.
WTB:
Veils (pre-2020)
TipTop stackable cables

FS:
Arturia Beatstep Pro (white) - £150 + shipping
Antumbra 6MIX - £75 + shipping
Kassutronics Slope 2 - £110 + shipping

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Re: Kassutronics VC Slope

Post by cartertools » Mon Nov 30, 2020 12:38 am

BWBKc6VyUr wrote:
Tue Nov 24, 2020 9:59 am
I'm building a couple of those right now. I just thought I'd highlight something that caught me off guard for the benefit of potential future builders.
Save yourself the headache and order a single 12-pin socket for J15 & J16 instead of two 6-pin.
Good point! I just built 3 and had cut down 40 pos sockets into 6 pos ones and then had to file the ends to butt together when I could have saved time and just made them 12 long. Only problem with an otherwise excellent and relaxing project.

Kassu didn't specify resistor wattage in the BOM, I assumed they would be 1/8 W as in his other builds but wasn't sure as the spacing allowed 1/4 W so I emailed him and he confirmed either is fine.

I ran out of TL072, only had 4 for one of them, thought I had ordered some, couldn't find them. So I used TL062 in one and TL082 in the other. Then after putting them in my case found the missing TL072s. Maybe I'll switch them out, maybe I won't. Haven't noticed any difference between them.

Having a lot of fun making Krell type patches using them.

I posted this picture of them in the "show us your build" thread but I'll post it again here.
slope3x.jpg

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Re: Kassutronics VC Slope

Post by BWBKc6VyUr » Mon Nov 30, 2020 4:57 am

cartertools wrote:
Mon Nov 30, 2020 12:38 am
Only problem with an otherwise excellent and relaxing project.
Agreed
cartertools wrote:
Mon Nov 30, 2020 12:38 am
Kassu didn't specify resistor wattage in the BOM, I assumed they would be 1/8 W as in his other builds but wasn't sure as the spacing allowed 1/4 W so I emailed him and he confirmed either is fine.
I asked him the same thing, his response to me was more specific: "For 1k resistors 1/4W (or higher) is best, the rest can also be 1/8W" (verbatim).
WTB:
Veils (pre-2020)
TipTop stackable cables

FS:
Arturia Beatstep Pro (white) - £150 + shipping
Antumbra 6MIX - £75 + shipping
Kassutronics Slope 2 - £110 + shipping

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Re: Kassutronics VC Slope

Post by Jarno » Mon Nov 30, 2020 5:58 am

Thanks for the suggestions, currently stuffing two of these, TLC3702 is proving to be somewhat harder to find (looks like either Mouser and put in a bigger order for other things as well, or eBay).

I stuff most boards with 0207 sized resistors, but I do have some smaller ones which I sometimes use. Just did some calculations, and apparently one doesn't need that much current for the power to rise above 0.125W, so yeah, need to pay attention to that.

Usually do not use headers for board to board, I try to use band cable and prevent connectors which can fail.

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Re: Kassutronics VC Slope

Post by BWBKc6VyUr » Mon Nov 30, 2020 6:43 am

Jarno wrote:
Mon Nov 30, 2020 5:58 am
Usually not use headers for board to board, I try to use band cable
I'm not sure you can do that here as the headers also act as board-to-board spacers.
WTB:
Veils (pre-2020)
TipTop stackable cables

FS:
Arturia Beatstep Pro (white) - £150 + shipping
Antumbra 6MIX - £75 + shipping
Kassutronics Slope 2 - £110 + shipping

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Re: Kassutronics VC Slope

Post by cartertools » Mon Nov 30, 2020 11:20 am

BWBKc6VyUr wrote:
Mon Nov 30, 2020 4:57 am
I asked him the same thing, his response to me was more specific: "For 1k resistors 1/4W (or higher) is best, the rest can also be 1/8W" (verbatim).
Well I guess I'll swap the 1k out if/when I swap TL072s in for my substitutes. Or I'll just be a test subject and see if it really does matter.

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Re: Kassutronics VC Slope

Post by BWBKc6VyUr » Mon Nov 30, 2020 11:38 am

cartertools wrote:
Mon Nov 30, 2020 11:20 am
see if it really does matter
If you use undersized resistor (e.g. 1/8W where 1/4W are required), they will overheat and in the worst case your appliance could catch on fire. I haven't done any calculations myself but Caspar wasn't too specific so it may not matter here.
WTB:
Veils (pre-2020)
TipTop stackable cables

FS:
Arturia Beatstep Pro (white) - £150 + shipping
Antumbra 6MIX - £75 + shipping
Kassutronics Slope 2 - £110 + shipping

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Re: Kassutronics VC Slope

Post by 040B » Mon Nov 30, 2020 2:00 pm

BWBKc6VyUr wrote:
Mon Oct 12, 2020 7:24 am
Has anybody built one yet? I’m curious about the cost of parts, wonder what’s e.g. Mouser basket ballpark for a unit.
I built two.

I don’t fully know the price of parts. Most of it are standard items that I have in stock. I used 1/8w resistors that I had left over from other Kassutronics builds.

Image

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Re: Kassutronics VC Slope

Post by solaranus » Mon Nov 30, 2020 2:52 pm

Jarno wrote:
Mon Nov 30, 2020 5:58 am
Thanks for the suggestions, currently stuffing two of these, TLC3702 is proving to be somewhat harder to find (looks like either Mouser and put in a bigger order for other things as well, or eBay).

I stuff most boards with 0207 sized resistors, but I do have some smaller ones which I sometimes use. Just did some calculations, and apparently one doesn't need that much current for the power to rise above 0.125W, so yeah, need to pay attention to that.

Usually do not use headers for board to board, I try to use band cable and prevent connectors which can fail.
I got mine from here: https://www.ebay.de/itm/2-pcs-TLC3702CP ... Sw-jhT-yhV They also have them on their own webpage but shipping is cheaper if you just need these chips and buy from their eBay page: https://www.darisusgmbh.de/shop/product ... s_id/60105

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Re: Kassutronics VC Slope

Post by solaranus » Mon Nov 30, 2020 3:08 pm

Also I got a few questions too,

first of all this might be a novice thing to ask but I guess changing the shape is supposed to change the attack and rise time as well? As in, logarithmic shapes are slower than linear shapes and exponential shapes faster? It was kinda confusing because of this figure:
Image
Another thing, when is the bicolor LED supposed to change colors? Mine follow the shape but it's always the same color.

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Re: Kassutronics VC Slope

Post by EASYBOY » Tue Feb 16, 2021 2:20 pm

This VCS looks nice.
Question To the DIY pros:
How hard is this build?

I only build the turing machine.
So this pcb looks like i could make it

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Re: Kassutronics VC Slope

Post by 040B » Tue Feb 16, 2021 3:43 pm

EASYBOY wrote:
Tue Feb 16, 2021 2:20 pm
This VCS looks nice.
Question To the DIY pros:
How hard is this build?

I only build the turing machine.
So this pcb looks like i could make it
This is a relatively easy build. If you have built something like the Turing machine before, this should be perfectly doable.

His build docs are very elaborate. A lot of information on the module. Just not a step by step build guide. But the silkscreen should provide you all information you need to place the components.

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Re: Kassutronics VC Slope

Post by nigel » Tue Feb 16, 2021 11:31 pm

A bit late, but I thought this deserved a comment:
solaranus wrote:
Mon Nov 30, 2020 3:08 pm
first of all this might be a novice thing to ask but I guess changing the shape is supposed to change the attack and rise time as well? As in, logarithmic shapes are slower than linear shapes and exponential shapes faster?
Not really, Ideally, you would arrange the circuit so that the times would stay the same length, just follow a different curve over time. (As in that diagram.) However, when you start changing the shape of the curves, it's very hard to make the total time the same.

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Re: Kassutronics VC Slope

Post by pugix » Wed Feb 17, 2021 11:48 am

solaranus wrote:
Mon Nov 30, 2020 3:08 pm
Another thing, when is the bicolor LED supposed to change colors? Mine follow the shape but it's always the same color.
That's because when looping or generating an envelope the output voltage stays positive. If instead you patch a signal to the input for slewing, when the input goes negative you'll see the LED in the other color, because the output follows the input. Some slews (like the SSF Mini Slew) only indicate when the output is positive, even though it can become negative when following an input.
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Re: Kassutronics VC Slope

Post by solaranus » Wed Feb 17, 2021 2:14 pm

nigel wrote:
Tue Feb 16, 2021 11:31 pm
A bit late, but I thought this deserved a comment:
solaranus wrote:
Mon Nov 30, 2020 3:08 pm
first of all this might be a novice thing to ask but I guess changing the shape is supposed to change the attack and rise time as well? As in, logarithmic shapes are slower than linear shapes and exponential shapes faster?
Not really, Ideally, you would arrange the circuit so that the times would stay the same length, just follow a different curve over time. (As in that diagram.) However, when you start changing the shape of the curves, it's very hard to make the total time the same.

Yeah, after a while I was reading the description of a digital module and saw the mention of the length staying the same with different shapes as a feature. I guess feeding the output back to input is not that precise. I only found it weird because I was expecting to having an envelope and changing the shape for a little variation but for my ears, but one has to change shape and time together to get a similiar effect.

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Re: Kassutronics VC Slope

Post by solaranus » Wed Feb 17, 2021 2:16 pm

pugix wrote:
Wed Feb 17, 2021 11:48 am
solaranus wrote:
Mon Nov 30, 2020 3:08 pm
Another thing, when is the bicolor LED supposed to change colors? Mine follow the shape but it's always the same color.
That's because when looping or generating an envelope the output voltage stays positive. If instead you patch a signal to the input for slewing, when the input goes negative you'll see the LED in the other color, because the output follows the input. Some slews (like the SSF Mini Slew) only indicate when the output is positive, even though it can become negative when following an input.

Thanks for the explanation! This made me realize I have not used them for slewing till now so did not see it changing color yet. Should try that out.

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Re: Kassutronics VC Slope

Post by EASYBOY » Sun Feb 21, 2021 3:36 pm

Reichelt doesnt stock the IC TLC3702 mentioned in the BOM. Only: IC TLC 372
Would it be okay to use that one?

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