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Another SubOsc

by isak on Wed Mar 07, 2012 8:05 am

Hi Guys

I found a SubOsc stripboard layout, really cool and easy to make but it belong to the Jen sx1000 synth.
The Question is could it be assembled in the x0x?
http://www.cykong.com/Synths/Jen%20SX10 ... pboard.gif
http://www.milton.arachsys.com/nj71/img ... subosc.gif
Please note that in the stripboard 10n is missing.

What do you think? Could it be done?

Cheers,
Isak E.
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Re: Another SubOsc

by Altitude on Wed Mar 07, 2012 11:36 am

i played around with 4024 based one and didnt get very good results. very buzzy. I think when its a divide down type deal like this it really does not turn out that great. I did one like this and the MC202 one that Castro had up on his site and both were lackluster. If you want a proper sub, then a second vco is the way to go
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Re: Another SubOsc

by isak on Wed Mar 07, 2012 3:33 pm

thank you for your reply.

you are right, i attend to try it on the second x0x vco mod, my only thought is if i take the signal from the the second vco switch (or what ever i take the sound from) the return of the sound will have to go through the main output of the second vco, that means that i will hear the original sine wave (saw/square) with the sub sine wave.
how do i separate them?
this is what i mean

Image

huge credit to Sub 2VCO, great mod!
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Re: Another SubOsc

by Altitude on Wed Mar 07, 2012 3:37 pm

Thats not really what I meant, I meant that if you want a sub oscillator that sounds good, take the 2nd vco and just tune it an octave below the main osc.
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Re: Another SubOsc

by isak on Wed Mar 07, 2012 3:48 pm

hooo... :oops:

but it will give me only one octave down, if i want the option to have -1 and -2 octave..?
i dont see a way to do it with the 2VCO.
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Re: Another SubOsc

by guest on Wed Mar 07, 2012 6:47 pm

if you get finely matched capacitors
you could switch in a second capacitor in the vco
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Re: Another SubOsc

by isak on Thu Mar 08, 2012 4:00 am

thank for replying guest.

if you get finely matched capacitors

sorry, i dont understand what is finely matched capacitors are.

you could switch in a second capacitor in the vco

i guess it related some how to the finely matched capacitors?
can you explain a bit more please?

BTW i found the SH101 based sub osc, i stripboard it :)

Image

Image

suppose i will not take the output to q12 in the x0x and plug it in a VCA module.

thanks again,
Isak E.
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Re: Another SubOsc

by guest on Thu Mar 08, 2012 5:48 pm

c33 on the x0x sets the frequency
so if you double the value you half the frequency
so you can put one capacitor in parallel with it
and switch it in or out to double the capacitance
but this only works if they are matched very well
or you have a trimmer cap to deal with the offset
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Re: Another SubOsc

by isak on Fri Mar 09, 2012 2:44 am

Thank you for that info guest!
Q..
If I triple the value will give me -2 octave?

Another Q..
I want to take the second vco as unit by it self and bass boost it, can I do that?
like the bass boost mod but only to the VCO.

Thanks guest that's really helpful!
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Re: Another SubOsc

by guest on Fri Mar 09, 2012 3:02 am

the bass boost depends upon what you are driving
it doesnt actually effect the signal being generated
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Re: Another SubOsc

by isak on Fri Mar 09, 2012 3:28 am

thank you.
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