Accent issue

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isak
 
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Accent issue

Post by isak »

Hi guys, long time :)

I have a friend x0x here that have a problem with the accent.
The accent works but the filter of the accent (the wow..wow) is not working.
What should I check first?

Cheers,
Isak E.
Last edited by isak on Sun Apr 27, 2014 4:09 am, edited 1 time in total.

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antto
 
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Re: Accent issue

Post by antto »

check at D24 (on the leg towards R47), you should have a steady voltage around 3V
then, play accented notes (and make sure the accent knob is at max) - see if the voltage goes above 3V or not

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isak
 
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Re: Accent issue

Post by isak »

Cheers Antto.

I'll let you know later on..

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isak
 
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Re: Accent issue

Post by isak »

Hi Anttto.

i know its been a while but i finally got around to check this.
i get 3.24V on D24 towards R47.
what should i check next?

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antto
 
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Re: Accent issue

Post by antto »

while measuring/probing at D24 - set the accent knob at max and play accented notes, see if the voltage jumps above the normal 3.24V

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isak
 
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Re: Accent issue

Post by isak »

yes it does

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antto
 
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Re: Accent issue

Post by antto »

and you have nothing?!
check R72 and R46, make sure they're not broken and/or the wrong value..
if they are not, it would help if you record a little audio with the accent and resonance at max, high cutoff and zero envmod

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isak
 
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Re: Accent issue

Post by isak »

R46 = 46.9k
R72 = when on board 87.3k, off board 98.9k

here is the audio clip, the 2 bumping things in the pattern should be the accented notes.
https://www.sendspace.com/file/iafiqx

it seems that it doesnt have the wow (filter swift bark)

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antto
 
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Re: Accent issue

Post by antto »

your MEG envelope is bad, the decay time is too short, that's why you're not getting enough "wow"
check C62, R138, the decay pot and such..
if you have another working x0x - compare voltages and resistance in-circuit between the two and see if you can quickly find what's going on
you'd get a shorter decay time if some resistance is effectively lower to ground..

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isak
 
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Re: Accent issue

Post by isak »

Well it's an Chinese x0x, the didn't put well all the components.
Now I've notice that that c62 is 100nF ceramic instead of 1uF tantalum.
They even put the same at c42!
I'll replace that as soon as I can and let you know.
I didn't even thought they will do that.
How low they can get?!?!?

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diplowave
 
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Re: Accent issue

Post by diplowave »

Ceramic capacitors C62 and C42, it is not good for the env and the decay. I think this is to save money they took ceramics. The tantalum are more expensive.

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isak
 
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Re: Accent issue

Post by isak »

Even when saving money, there needs to be a limit that you don't cross.
They selling a bad machines that doesn't work as it should.
Ok, save money but sell a good working machine, don't you think?

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