x0xi0 full kit with mixer pcb inside

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kroutshev
 
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Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Yep you're right Brian, i'm very happy to have now x0xi0 sound with clean output signal :-) !
Thanks again and that's true i have read ur last manual where you indicate noise problem with vca in mods !
Ok i have removed that mod from my first x0xi0 but unfortunaly i have a sound very low . i have plugged vcf out and vco out, volume and sound are good but when i plug mix out output the volume is very low ??? what i have unplugged ? i have looking for a flying wire but i see nothing .
Do you have any idea where i have to check ?
Thanks

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Ok when i turn vco1 and vco2 level, it change nothing at the sound ... it's like vco1 and vco2 levels are always at zero.

bcbox
 
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Joined: Thu May 25, 2006 1:30 am

Re: x0xi0 full kit with mixer pcb inside

Post by bcbox »

The VCF Out, VCA In arrangement changed with the latest version so I'm sure it has to do with this.

1. Make sure the trace between R121/R122 and IC15Pin3 is not cut like in the old version of the install manual. You can check this from the component side using your multimeter to check the resistance between these points.
2. Remove R344 & R345 on the x0xi0 I/O board.
3. Check page 52 of the install manual and make sure the VCF Out is hooked up this way.
http://alphazone1.com/x0xi0/install/full_section6.html

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Ok Brian,
i'll do that tonight !
we get in touch !
Thanks.

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

bcbox wrote:The VCF Out, VCA In arrangement changed with the latest version so I'm sure it has to do with this.

1. Make sure the trace between R121/R122 and IC15Pin3 is not cut like in the old version of the install manual. You can check this from the component side using your multimeter to check the resistance between these points.
2. Remove R344 & R345 on the x0xi0 I/O board.
3. Check page 52 of the install manual and make sure the VCF Out is hooked up this way.
http://alphazone1.com/x0xi0/install/full_section6.html
Ok i have done what you have wrote me ! I have fixed trace previously cut, removed R344 and R345 in x0xi0 i/o board and join wire with 1k resistor between K and C21 for vcf out ... and now i have no sound from mix out, vco out and vcf out.
are you sure that i have to removed R344/R345 ?
I use BA662A in that model.
THanks

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Help Brian,
still no sound with my x0xi0 ? what's the problem ?
Thanks

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Hi Brian,
i have checked connection again last night and i don't see where is the problem. Why is it good with the last x0xi0 and not good with my first ? the thing that i don't understant is even if i have cut the trace between IC15 pin 3 and R121 also into the last x0xi0 and i have continuity when i check with my multimeter ???
Since i have removed vca in wire i have no sound into mix out and since i have put wire to have continuity between IC15 and R121 i have no sound int vco out, vcf out and mix out ???
Please could you explain me where is the problem ???
Thanks.

bcbox
 
Posts: 587
Joined: Thu May 25, 2006 1:30 am

Re: x0xi0 full kit with mixer pcb inside

Post by bcbox »

I'm on vavaction with limited access so I may be slow responding until I get back on January 3rd!
Everything you did looks good. Since you have no VCO Out I think maybe another wire came loose during fixing.

Re-check these:
1. pad T on x0xi0 I/O pcb to pad T on x0xi0 top pcb.
2. pad S on x0xi0 I/O pcb to C17(-) on x0xb0x mainboard.
3. pad K on x0xi0 I/O pcb to 1k resistor and then to C21 as shown in Install Manual.
4. Remove any wires connected to Pad J on x0xi0 I/O pcb.

If all these still look good check for the VCO waveforms at pad T on the x0xi0 I/O pcb. You should see/hear the waveform here. If ok then check at pad S, this is after the VCO Out jack, you should still see/hear the waveform here.

We'll go from here. happy holidays!

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Hi brian,
thanks for your reply :-) ! but i'm in vacation too :-)) !
i will check next week !
Have a nice time during your holydays and i will let you know when it's ok !
K.

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Ok Brian,
hope that you have past some nice BANNED :-) !
I send you my best wishes for this new year 2011 !
I have checked wires and pad T K and S are correct. No wire on J but still no sound !
I can hear only noise from distorsion effect when i activate it !
But no sound from mix out and from vco out. I have check pin 3 from vr405 and 406 and no sound, no signal into my oscilloscope !!
It seems that i have remove wire before vco but i see no flying wire ???
i don't understand what's happen.
I have rewire cut trace to have continuity between IC15 pin 3 and R121 : is it correct ?
why i have to remove resistors R344 and R 345 ?
can you explain me what's the difference between the new x0xi0 and the first one. I have checked and compared the two version of install manual and the only difference is about pad k with 1k resistor. Why i have continuity between IC15 pin 3 and R121 into my last x0xi0 even if i have cutted trace ??
Thanks for your informations.
All the best.

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Please Brian could you help me ?
Thanks.

bcbox
 
Posts: 587
Joined: Thu May 25, 2006 1:30 am

Re: x0xi0 full kit with mixer pcb inside

Post by bcbox »

I have rewire cut trace to have continuity between IC15 pin 3 and R121 : is it correct ?
yes, or else the signal from the filter will not make it to the VCA.
why i have to remove resistors R344 and R 345 ? can you explain me what's the difference between the new x0xi0 and the first one.
The screenshots below might help.

a) VCF Out was changed.
in version 1, the signal from the filter was sent to the VCF Out jack and then routed back to the VCA Input.
This is why you see the VCF Out signal coming in on the tip of jack J309 (pad K) and then going back to the VCA on the (normally-closed) switched terminal though R344 and to pad J.
This was ideal since a switched jack was used so that when you plug a cable into the VCF Out jack the signal does not go to the VCA, so that you can route it back to the VCA later.
However, this gives too much opportunity for noise, so this was changed, so now the signal from the filter goes directly to the VCA In as usual (no cut trace, no sending signal to the jack first).
This is why the connection between R121/R122 and IC15 is no longer cut and needs to be reconnected if upgrading from version 1 to version 2.
Now, in version 2, the VCF Out signal is simply tapped off of C21 and goes directly out to jack J309 through the 1k resistor, and R344 should be removed.

b) The VCA In circuit is unchanged. However, if you are not using the VCA In jack it is ok to remove C27 and/or R345 as they aren't being used.

Image

Image

Image

About the problems now, it sounds like you have nothing from the VCO. Probably a wire came loose, maybe from J3 or something else. check the following.
J3 (all wires), all wires connected to pads 2 through pad 10.

Try this:
1. Program a pattern, alternating between C1 and C3.
2. Check the DC voltage at pin 7 of IC11. This is the control voltage for the VCO's. You should see it jumping between 2V and 4V for example for notes C1 and C3 (control voltage for notes is 1V/octave). If you only have a multimeter then program a long C1 note and then a long C3 note so that you meter can settle, and you should see 2V and then 4V etc.. If this is ok the the signal from the microcontroller is ok and the DAC is working.
3. Check supply voltages. Pin 8 of IC11 and IC401 should be ~11.85V, pin 3 of IC11 and IC401 should be ~5.33V.
4. Check the collector of Q8 and Q406, this is the square output of each VCO before they go to the waveform select switch.

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Great Brian,
thanks for the informations about the resistors.
Ok i'll check tonight !
I will let you know asap !
K.

kroutshev
 
Posts: 146
Joined: Thu Oct 30, 2008 9:00 am

Re: x0xi0 full kit with mixer pcb inside

Post by kroutshev »

Ok Brian,
i have found the problem ! J4 wires on mainboard were flying !
Now it's good, thanks a lot my x0x is working ... but now when i turn to 0 the decay accent pot i cut the sound as volume pot ???
Before modification that's working well ??
And about clicks they are gone :-) !! no more click and great sound !
Thanks again Brian !-]

bcbox
 
Posts: 587
Joined: Thu May 25, 2006 1:30 am

Re: x0xi0 full kit with mixer pcb inside

Post by bcbox »

but now when i turn to 0 the decay accent pot i cut the sound as volume pot ???
Re-check the connection for Accent Decay as shown in page 64 & 65 of the install manual. Work very slow and try not to tear out any more of the wires (I know it's hard!)

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