[sdiy] DIY patch matrix idea

Oren Leavitt obl64 at ix.netcom.com
Sat May 21 22:30:22 CEST 2016


My initial idea is that the plug would contain a 100K resistor and will 
insert this between the one output (column) and a virtual ground summing 
node input (row). Inserting several plugs on the same input row, it 
becomes like a standard summer with each output connected thru a 100K 
resistor.

One could also place the 100K resistors in the patch panel connecting 
each jack to the input summing node row, and simply short the plugs.
You could also have AC coupling plugs with a capacitor in them instead 
of a short, or an additional resistor for attenuation.

- Oren

On 5/21/2016 2:59 PM, Tim Ressel wrote:
> Your low tech solution is a pretty great idea. So you'd use stereo jacks
> and shorted stereo plugs? Does that mean you'd have to be careful to
> only patch one input to an output? Or is there a clever way around that
> as well?
>
> --tr
>
>
>
> On 5/21/2016 12:48 PM, Oren Leavitt wrote:
>> Yeah, the push switches are definitely an idea. I was toying with the
>> "low tech" jacks/plugs approach as I have a lot of them laying around.
>>
>> Jim, I was thinking plain old panel mount jacks.
>>
>> I certainly love the electronic switching solutions available today.
>> It is a far cry from my first crack at a 4x4 matrix using 4016s some
>> years ago.
>>
>> - Oren
>>
>> On 5/21/2016 1:17 PM, sleepy_dog at gmx.de wrote:
>>>
>>> ah, and here's a slightly more expensive one with cap:
>>> http://shop.boxtec.ch/mini-self-lock-push-switch-6pin-8x8mm-p-42036.html
>>>
>>> Also, should you ever need to shoot rockets off your gear (like Keith
>>> Emerson, R.I.P.), there you go:
>>> http://shop.boxtec.ch/missile-switch-with-cover-p-40540.html
>>>
>>>
>>> Steve
>>>
>>>
>>> Am 21.05.2016 um 20:12 schrieb sleepy_dog at gmx.de:
>>>>
>>>> how about using an array of small switches (no idea what they're
>>>> called) like those here?
>>>> maybe with 2 sets of contacts, one of which is used to enable a led.
>>>> But perhaps it's also visible enough which are "on"  (because they are
>>>> lower) without led.
>>>>
>>>> Mini Self Lock Push Switch 6pin - 7x7mm, Simple and small 7 x 7mm
>>>> 6-pin 3PST switch for PCB mounting
>>>> http://shop.boxtec.ch/mini-self-lock-push-switch-6pin-7x7mm-p-42038.html
>>>>
>>>>
>>>> 0.80 CHF pretty much equals 0.80 USD, if you buy 50 pcs, it's only
>>>> 0.41 / piece. For 8x8=64 that'd be < 27 USD
>>>> Sounds bearable.
>>>>
>>>> Steve
>>>>
>>>>
>>>> Am 21.05.2016 um 18:35 schrieb Jim Patchell:
>>>>> Oren-
>>>>>
>>>>> Struck a nerve with me.  However, so far, I have not been able to
>>>>> locate PCB mount Vertical 3.5mm stereo phone jacks.  Is this what you
>>>>> were planning to use?  And if so, could you clue me in to who sells
>>>>> them?  Mouser, Digikey, Tayda and Small Bear all have come up short.
>>>>>
>>>>> -Jim
>>>>>
>>>>>
>>>>> On 5/20/2016 8:09 PM, Oren Leavitt wrote:
>>>>>> With sources of ready-made patch matrix solutions being scarce, I
>>>>>> have been mulling over ideas for a DIY patch matrix.
>>>>>>
>>>>>> I am thinking of using 2.5mm or 3.5mm stereo TRS mini phone jacks
>>>>>> arranged in a matrix. These can purchased in bulk for reasonable
>>>>>> prices. The tips would be wired as "columns" connecting to a source.
>>>>>> The rings wired as "rows" connecting to a summing node input.
>>>>>>
>>>>>> The plugs would house a standard 100K resistor wired from the tip
>>>>>> (source) to the ring (summing node input). Additional "special"
>>>>>> plugs can be fitted with smaller or larger resistors for added gain
>>>>>> or attenuation, or an AC coupling capacitor.
>>>>>>
>>>>>> These jacks could even be used as "inserts" for an external signal
>>>>>> processor between source and input.
>>>>>>
>>>>>> - Oren
>>>>>> _______________________________________________
>>>>>> Synth-diy mailing list
>>>>>> Synth-diy at dropmix.xs4all.nl
>>>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Synth-diy mailing list
>>>>> Synth-diy at dropmix.xs4all.nl
>>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>>>
>>>>
>>>
>>> _______________________________________________
>>> Synth-diy mailing list
>>> Synth-diy at dropmix.xs4all.nl
>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>
>> _______________________________________________
>> Synth-diy mailing list
>> Synth-diy at dropmix.xs4all.nl
>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>
>
> --
> --Tim Ressel
> Circuit Abbey
> timr at circuitabbey.com
>
>
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>



More information about the Synth-diy mailing list