# Difference between sum or multiply modules ?

hi,

1)what is the difference between a sum and a multiply?

2)what’ does it mean in MIDI CV:

RTRG

CLK/N

AFT

PW

MW

3)i search for a module with:

a)4 inputs for Gate to 1 output for Gate

b)1 input for Gate to 4 outputs for Gate

c)4 inputs for CV to 1 output for CV

d)1 input for CV to 4 outputs for CV

e)4 input for VEL to 1 outputs for VEL

f)1 input for VEL to 4 outputs for VEL

g)4 input for CLOCK to 1 output for CLOCK

h)1 input for CLOCK to 4 outputs for CLOCK

i)4 inputs for RUN to 1 output for RUN

j)1input for RUN to 4 outputs for RUN

k)perhaps is there exist a module combining a+b+c+d+e+f+g+h+i?

If yes,which?

thanks

Hi @obywanna–happy to help, but can you first change the topic title to something more descriptive so that others can be helped in turn in the future? Thanks! For an example, here’s a bit from the Rules:

• Titles of threads should be as descriptive as possible in one sentence. “Need help” is not acceptable and will be removed or changed. “What module can extend a gate signal?” is a better title.

the difference between multiply and sum, is exactly like you learned in the school (but applied to voltages) , depending of the case you will prefer use one or other.

considerate this: if you have a first voltage, and you add as sum a second voltage , the result voltage always will be an offset of the first one

multiplying voltages work a bit different for instance if one of the voltages is zero, the result always will be zero until the initial voltage change , also decimal matter , if you multiply a voltage by 0.5, you will get half of the first voltage , and so on

perhaps it could be interesting to read
https://vcvrack.com/manual/VoltageStandards

there are lots of modules to allow you to know what voltage are you getting in a signal from the scope to one of my fab hovering value

all the midi cv outputs are specified here VCV Manual - Core Modules

a mixer (whatever of them )

also the fundamental Unity , it allow sum and average (and the inverse)

edited : I pressed the wrong reply button it is not a answer to @gc3 , is a answer to the original post

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could you explain what you want to do?

for all the 1 to X in you list, you can connect whatever arbitrary number of cables in a output

for all t the X to 1 in your list you could mix whatever arbitrary number of cables (using mixers , sum, etc ) then, connect to the input

one more thing, there are not difference between the nature of the signals, all them are voltages, you can use a module for all purpose, you can use the unity (for instance ) to mix cv ,audio , triggers or whatever

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About Midi CV :

RTRG : Retrigger (i think)

CLK/N : Clock

AFT : Aftertouch

PW : Pitch wheel

MW : Mod wheel

I found the solution for 3):

a sum (X to 1)

a multiply (1 to X):

If i want (X to X),i use a sum with a multiply by plugging the output of sum in input of multiply

by taking care to use a sum or a multiply for each type of signal(CV,CVA,GATE,RUN,CLOCK,…)