Kassutronics VC Slope

[pugix]

Looks like fun!

https://kassu2000.blogspot.com/2020/10/slope.html

[appliancide]

Cool trick to get an ADSR out of that circuit!

[pugix]

Cool trick to get an ADSR out of that circuit!

After Later Audio Tilt has this feature, too.

https://afterlateraudio.com/product/tilt/

[SphericalSound]

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

[BWBKc6VyUr]

Has anybody built one yet? I’m curious about the cost of parts, wonder what’s e.g. Mouser basket ballpark for a unit.

[Jarno]

Ordered 2 PCB's (despite having 4 VCS's already , one cannot have enough slope generators)

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.

[BWBKc6VyUr]

Wooden front panels though?

[BWBKc6VyUr]

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:

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.

[cartertools]

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.

[BWBKc6VyUr]

Only problem with an otherwise excellent and relaxing project.

Agreed

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).

[Jarno]

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.

[BWBKc6VyUr]

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.

[cartertools]

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.

[BWBKc6VyUr]

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.

[040B]

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.

[solaranus]

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

[solaranus]

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:

Another thing, when is the bicolor LED supposed to change colors? Mine follow the shape but it's always the same color.

[EASYBOY]

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

[040B]

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.

[nigel]

A bit late, but I thought this deserved a comment:

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.

[pugix]

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.

[solaranus]

A bit late, but I thought this deserved a comment:

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.

[solaranus]

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.

[EASYBOY]

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