WMD Sequential Switch Matrix

[tioJim]

Hello

Can you manually select a matrix in a single move? Something like [button] + [matrix 1 - 16]

If you can’t I’ll be sad.

Would be a good performance feature

Jim

[BaloErets]

Hello

Can you manually select a matrix in a single move? Something like [button] + [matrix 1 - 16]

If you can’t I’ll be sad.

Would be a good performance feature

Jim

Not built into the module but you could easily do so by using some kind of stored voltage plugged into the CV input. That would allow you to address any of the matrix' presets.

[boramx]

Hello

Can you manually select a matrix in a single move? Something like [button] + [matrix 1 - 16]

If you can’t I’ll be sad.

Would be a good performance feature

Jim

pretty sure no.

but with CV address you could make this happen. a manual controller such pressure points, rené, Voltage memory, etc.

even manual gates through attenuators.

[tioJim]

Then I haz a sad :(

But you’re both right! All is not lost. Shame though, seems like an obvious one?

I have PP which I play manually as well as sequence with Brains so they’d pair quite well and fit my existing workflow

Thanks

[BaloErets]

Then I haz a sad :(

But you’re both right! All is not lost. Shame though, seems like an obvious one?

I have PP which I play manually as well as sequence with Brains so they’d pair quite well and fit my existing workflow

Thanks

Yeah! I use PP all the time to do exactly that. Works like a charm

[huffnPuff]

Can you daizy chain matrices like you can with the 4ms VCAM? A patch I'm working on requires an 8 inputs x 4 outputs matrix.

[mdoudoroff]

Can you daizy chain matrices like you can with the 4ms VCAM? A patch I'm working on requires an 8 inputs x 4 outputs matrix.

Allegedly, with at least one caveat. Check out the second page of the manual.

https://cdn.shopify.com/s/files/1/0977/ ... 8609552331

[huffnPuff]

The manual crashes the browser on my phone for some reason. So, not really if I understand you.
With the digital control element it's not trivial I guess. With the VCAM you connect two modules with a ribbon cable and that's it.

Thanks.

[defenestration]

section in manual on rear connections -

3. MixOut. This connector provides the outputs of each channel at the rear of the SSM. Red Stripe Down.
4. MixIn. This connector provides unity gain access to the inputs of each channel. Red Stripe Down. Connecting the MixOut to MixIn on a second SSM will pass all signals from the first to the second. Effectively giving 8 inputs to the second SSM. Beware that these inputs will be out of phase on the second module.

[huffnPuff]

Ok, so it's practically the same as the VCAM. Thanks!

[Paranormal Patroler]

Does anyone have a pinout for the 20-pin expansion header on the back? If I could access the state of the button matrix directly it would open up some awesome DIY expander options.

Will start at pin 1 which is bottom Right of the 20 pin header. Then go Right Left and then up.
These are high (5V) when the connection is made. They are unbuffered so be careful connecting them without a resistor to anything. Do not use them as direct outputs to jacks without some sort of buffering.
1: 4-4
2: 4-3
3: 4-2
4: 4-1
5: 3-4
6: 3-3
7: 3-2
8: 3-1
9: 2-4
10: 2-3
11: 2-2
12: 2-1
13: 1-4
14: 1-3
15: 1-2
16: 1-1

17: Bank bit 0
18: Bank bit 1

19: Do not use (has to do with save and step)
20: Do not use (has to do with save and step)

If anyone manages to build a 4HP just-16-outputs trigger expander, I'd be SO into it. Heck just a 4HP with 8 outs for column 3 and 4 would be sweeeet.

You better buffer it if you do, the outputs on the header are not protected.

I'm trying to build a smaller expander for my recently purchased SSM (I can't believe I never had this module before). What does buffered mean exactly? I know the concept, I'm just not getting why there's anything more than some protection required. Wouldn't a passive module with 18 outputs and resistors for each connection work?

Also, do these signals (at the expansion header) stay at 5V as long as the connection is still on? Just curious if it's a trigger or a gate output.
Really holding my breath here, hoping I can get some answers. A small version of this expander would be delightful to have for a smaller case such as mine.

Thanks for any answers

[cptnal]

So you don't turn blue before someone can answer the electricky stuff, the SSM Expand can toggle between gates (with adjustable length under CV) or triggers. You can also toggle retrigger on step change (rather than a gate remaining high for the duration of two or more steps).

[desolationjones]

Does anyone have a pinout for the 20-pin expansion header on the back? If I could access the state of the button matrix directly it would open up some awesome DIY expander options.

Will start at pin 1 which is bottom Right of the 20 pin header. Then go Right Left and then up.
These are high (5V) when the connection is made. They are unbuffered so be careful connecting them without a resistor to anything. Do not use them as direct outputs to jacks without some sort of buffering.
1: 4-4
2: 4-3
3: 4-2
4: 4-1
5: 3-4
6: 3-3
7: 3-2
8: 3-1
9: 2-4
10: 2-3
11: 2-2
12: 2-1
13: 1-4
14: 1-3
15: 1-2
16: 1-1

17: Bank bit 0
18: Bank bit 1

19: Do not use (has to do with save and step)
20: Do not use (has to do with save and step)

If anyone manages to build a 4HP just-16-outputs trigger expander, I'd be SO into it. Heck just a 4HP with 8 outs for column 3 and 4 would be sweeeet.

You better buffer it if you do, the outputs on the header are not protected.

I'm trying to build a smaller expander for my recently purchased SSM (I can't believe I never had this module before). What does buffered mean exactly? I know the concept, I'm just not getting why there's anything more than some protection required. Wouldn't a passive module with 18 outputs and resistors for each connection work?

Also, do these signals (at the expansion header) stay at 5V as long as the connection is still on? Just curious if it's a trigger or a gate output.
Really holding my breath here, hoping I can get some answers. A small version of this expander would be delightful to have for a smaller case such as mine.

Thanks for any answers

Many microcontrollers cannot push very much current from the output pins. Functionally this means you need a power amplifier circuit to accomplish much. Some of these circuits also form effective controls against sourcing/sinking too much current from the MCU. And ESD protection is nice, too.

You should start by examining which microcontroller is in use on the SSM; how much current can its DO pins source? Then you will want to see if there are any other I/O expander ICs in the circuit (but I doubt there is).

This might seem like a lot if you are unfamiliar with electronics. You might start by reading some tutorials about how to turn on a light bulb with an Arduino or something. There's many ways to "step up" your ability to push current (transistors are a popular choice).

[Paranormal Patroler]

So you don't turn blue before someone can answer the electricky stuff, the SSM Expand can toggle between gates (with adjustable length under CV) or triggers. You can also toggle retrigger on step change (rather than a gate remaining high for the duration of two or more steps).

Not what I asked but sincere thanks for taking the time to answer. I'll keep holding my breath, hoping I'll get an answer from WMD

Many microcontrollers cannot push very much current from the output pins. Functionally this means you need a power amplifier circuit to accomplish much. Some of these circuits also form effective controls against sourcing/sinking too much current from the MCU. And ESD protection is nice, too.

You should start by examining which microcontroller is in use on the SSM; how much current can its DO pins source? Then you will want to see if there are any other I/O expander ICs in the circuit (but I doubt there is).

This might seem like a lot if you are unfamiliar with electronics. You might start by reading some tutorials about how to turn on a light bulb with an Arduino or something. There's many ways to "step up" your ability to push current (transistors are a popular choice).

Thanks for the advice! You raise a good point. I guess the 5V mention by WMD threw me off, it doesn't mean it's powerful enough to be at an output and it also makes sense that it needs to be protected. When plugging jacks sometimes current goes both ways, you never know.

Did you ever take advantage of the pinout you were given?!? I really want to make progress with this, but it seems way to difficult for my knowledge.

[WMDevices]

So you don't turn blue before someone can answer the electricky stuff, the SSM Expand can toggle between gates (with adjustable length under CV) or triggers. You can also toggle retrigger on step change (rather than a gate remaining high for the duration of two or more steps).

Not what I asked but sincere thanks for taking the time to answer. I'll keep holding my breath, hoping I'll get an answer from WMD

Many microcontrollers cannot push very much current from the output pins. Functionally this means you need a power amplifier circuit to accomplish much. Some of these circuits also form effective controls against sourcing/sinking too much current from the MCU. And ESD protection is nice, too.

You should start by examining which microcontroller is in use on the SSM; how much current can its DO pins source? Then you will want to see if there are any other I/O expander ICs in the circuit (but I doubt there is).

This might seem like a lot if you are unfamiliar with electronics. You might start by reading some tutorials about how to turn on a light bulb with an Arduino or something. There's many ways to "step up" your ability to push current (transistors are a popular choice).

Thanks for the advice! You raise a good point. I guess the 5V mention by WMD threw me off, it doesn't mean it's powerful enough to be at an output and it also makes sense that it needs to be protected. When plugging jacks sometimes current goes both ways, you never know.

Did you ever take advantage of the pinout you were given?!? I really want to make progress with this, but it seems way to difficult for my knowledge.

Using 1k output resistors should be sufficient protection. I would probably use 4.7k or more if you are going direct. The header pins are direct from the Atmel AVR series microcontroller. Without protection, connecting them to any voltages beyond 0-5V will smoke the entire microcontroller. 4.7k provides worst case protection of 3mA output current if connected to the -12V rail. The body diodes on the AVR can handle that, though I still recommend protection.

It's always recommended to totally protect the pins by using an isolating circuit like a transistor step up or a voltage level shifter IC. This also reduces the capacitive load on the pins making them switch faster.

5V is powerful enough to be an output, BUT it depends on what you drive with it. Some modules (usually very old units) don't interact well with 5V gates or triggers.

The signals at the expansion header stay at 5V, they are DIRECTLY COUPLED to the routing LEDs and switches on the SSM.

This information is offered with no warranty.

[desolationjones]

WMDevices thanks for adding some clarity to my guesses.


Paranormal Patroler I sadly sold my SSM long ago and never followed through. Don't get discouraged though because it sounds like maybe all you need is 4 x TL084, 16 x 1k resistor, 16 x TS jacks, and a couple headers!

[Paranormal Patroler]

Using 1k output resistors should be sufficient protection. I would probably use 4.7k or more if you are going direct. The header pins are direct from the Atmel AVR series microcontroller. Without protection, connecting them to any voltages beyond 0-5V will smoke the entire microcontroller. 4.7k provides worst case protection of 3mA output current if connected to the -12V rail. The body diodes on the AVR can handle that, though I still recommend protection.

It's always recommended to totally protect the pins by using an isolating circuit like a transistor step up or a voltage level shifter IC. This also reduces the capacitive load on the pins making them switch faster.

5V is powerful enough to be an output, BUT it depends on what you drive with it. Some modules (usually very old units) don't interact well with 5V gates or triggers.

The signals at the expansion header stay at 5V, they are DIRECTLY COUPLED to the routing LEDs and switches on the SSM.

This information is offered with no warranty.

Thank you very much for your input. Very much indeed.

Apologies for the newb questions. I'm really struggling to find a good way to move ahead with this DIY expander as I'm not sure whether a passive version with 4.7k protection between each pin and each jack would suffice, and whether your 'buffered' suggestions made earlier in this thread were aimed to cover both protection and any incompatibilies with "old units [that] don't interact well with 5V gates or triggers".

What I'm trying to ask is, does the expander need to be powered separately or just protecting the pins and bringing their 5V to the jacks would be enough (re: passive version)?

I like some of the features of the original expander, I really do, it's just that the negative space of the UI irks me for some reason, and I'm torn between losing functionality on my case by going for the 8hp, or going through the notions of making a 4hp version for myself and losing some cool stuff like the "invert" option.

[desolationjones]

You'd be fine-ish with a passive expander. This particular microcontroller can source a lot of current per pin. But then ESD will be a real concern since you're exposing the pins directly so consider adding clamping diodes.

[Paranormal Patroler]

You'd be fine-ish with a passive expander. This particular microcontroller can source a lot of current per pin. But then ESD will be a real concern since you're exposing the pins directly so consider adding clamping diodes.

Wouldn't a simple 4.7 resistor (as suggested above) between the pin and the jack do the work?

Also, any grounding required? There doesn't seem to be any pins for grounding. Not sure if that's necessary.

[WMDevices]

You'd be fine-ish with a passive expander. This particular microcontroller can source a lot of current per pin. But then ESD will be a real concern since you're exposing the pins directly so consider adding clamping diodes.

Wouldn't a simple 4.7 resistor (as suggested above) between the pin and the jack do the work?

Also, any grounding required? There doesn't seem to be any pins for grounding. Not sure if that's necessary.

4.7k yes.

Grounding, its in the case, for the gates it's not super necessary. Just ground all the jacks to the case.

[Paranormal Patroler]

Thank you WMD, you have been most kind and most helpful about this. It is very appreciated!

[Paranormal Patroler]

One more question for the back-pins: can the MixIn and MixOut pins become accessible with a passive expander? Do these need protection in the same sense that the GTExp needed some protection or can I just connect the pins to jacks and be ready to go?

I'm currently using the Manikk Otto passive stereo module to access things: https://www.modulargrid.net/e/manikk-ot ... ive-stereo and I have some spare jacks, it would be nice to get extra access via the MixIn in the back.

[WMDevices]

One more question for the back-pins: can the MixIn and MixOut pins become accessible with a passive expander? Do these need protection in the same sense that the GTExp needed some protection or can I just connect the pins to jacks and be ready to go?

I'm currently using the Manikk Otto passive stereo module to access things: https://www.modulargrid.net/e/manikk-ot ... ive-stereo and I have some spare jacks, it would be nice to get extra access via the MixIn in the back.

MIX IN has summing resistors already, so a passive/direct-to-jack expander can be made.

MIX OUT has 1k protection resistors, so a passive expander can be used. It's just the mult from the output jacks anyway, so likely no reason to do that.

[Paranormal Patroler]

Perfect! Can you tell us the pin mapping? I am really eager to try this out.
Once again, thank you for your reply. I know you're not obliged to give this info, but sometimes a DIY option is a very welcome solution in a smaller system.

[WMDevices]

Perfect! Can you tell us the pin mapping? I am really eager to try this out.
Once again, thank you for your reply. I know you're not obliged to give this info, but sometimes a DIY option is a very welcome solution in a smaller system.

Same for both MixIn and MixOut: Some versions of the module have 2x5 headers, some have 1x5 headers.

Bottom Row - GND
2nd Row - Channel 1
3rd Row - Channel 2
4th Row - Channel 3
Top Row - Channel 4