EURO x0x-heart - Complete "Kit"

From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive!

Moderators: Kent, luketeaford, Joe.

Post Reply
morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 2:18 pm

guest wrote:
Sun Dec 20, 2020 2:01 pm
so there is no change in the slid CV out in this case? if you run it at 2V, is there a change? if there is no change at 2V, then use the CV out from the x0xb0x again, and see if it changes.
Should I be doing these tests with the 1k resistor in place or not?

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 2:34 pm

with the 1k.
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 3:21 pm

Also, for these tests what should I have my VCA+VCF/Decay Decouple switch set to?

If you recall this switch was added so that I could have separate control over the VCA+VCF and Decay by decoupling U4 pin9 and U5 pin1. All of our correspondence regarding the pitch shift issues have taken place with the switch set in the decouple position.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 3:38 pm

ok, so leave the switch in the decouple position.
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 3:41 pm

With the 1k resistor in place and the decouple switch set to decouple and with the CV pitch source outputting 2v (from a module in the same case as the x0xheart) I don’t see any changes in the voltage at the Slid CV output (same results as using 5v at the CV pitch input).

And using the x0xb0x for CV pitch gives the same results, no voltage change.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 3:47 pm

excellent, we are getting somewhere now. so, can you set the CV in and accent gate up the way you had it before and see what it does? what other cables did you have plugged in in the previous test?
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 3:48 pm

I only see the voltage rise on the Slid CV output if I have a gate patched to the xoxhearts gate input and accent gate input and then feed voltage to the accents CV input.

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 3:51 pm

guest wrote:
Sun Dec 20, 2020 3:47 pm
excellent, we are getting somewhere now. so, can you set the CV in and accent gate up the way you had it before and see what it does? what other cables did you have plugged in in the previous test?
I had the xoxheart’s Gate input patched from the x0xb0x’s gate output. And a 5v signal patched to the accent CV input.

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 3:54 pm

... And also the x0xheart’s VCA output patched to my mixer.

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 3:57 pm

Patching things up the way they were, gate and pitch CV from the x0xb0x (minus the Plog switching stuff) I get the pitch rise when I add 5v to the x0xheart’s Accent CV input, same as before.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 4:07 pm

ok, so lets remove one part at a time and see what causes it. also, i think i may have been confused, its the accent CV and not the accent gate that is causing the problem? was your last test with just the 3 signals you mentioned connected? was the slid CV out still just going to the multimeter?
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 4:25 pm

guest wrote:
Sun Dec 20, 2020 4:07 pm
ok, so lets remove one part at a time and see what causes it. also, i think i may have been confused, its the accent CV and not the accent gate that is causing the problem?
I don’t know how to confirm which one is the cause as I can’t test the Accent CV input with out triggering the Accent Gate! But it’s definitely one of them or both?
guest wrote:
Sun Dec 20, 2020 4:07 pm
was your last test with just the 3 signals you mentioned connected? was the slid CV out still just going to the multimeter?
It wasn’t. But I tried it again, just x0xb0x pitch CV and Gate into x0xheart’s Pitch input and Gate input, 5v into x0xheart’s accent gate and a separate 5v into the x0xheart’s accent CV, and just the DMM connected to the Id CV output and I get the pitch rise from 2.020v to 2.142v.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 4:29 pm

ok, can you try with just the accent gate, and not accent CV plugged in (i expect that to behave the same).
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 5:07 pm

guest wrote:
Sun Dec 20, 2020 4:29 pm
ok, can you try with just the accent gate, and not accent CV plugged in (i expect that to behave the same).
When I remove the Accent CV patch cable the voltage at the Slid CV output jumps to 2.154v. However, if I then turn down the accent cv knob it goes back down to 2.020v. Is that the normal behavior? Or should the knob value only effect the x0xheart when there is voltage present at the Accent CV input?

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 5:18 pm

that is useful information. the knob works the same as accent CV in. can you listen to the x0xheart with accent gate, and turn the accent knob, and listen for pitch change? if it does, can you try turning the other knobs and see what effect it has? in particular, the ACCENT->RES knob and ENVMOD knob? the RES knob might also have an effect.
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 5:33 pm

guest wrote:
Sun Dec 20, 2020 5:18 pm
that is useful information. the knob works the same as accent CV in. can you listen to the x0xheart with accent gate, and turn the accent knob, and listen for pitch change? if it does, can you try turning the other knobs and see what effect it has? in particular, the ACCENT->RES knob and ENVMOD knob? the RES knob might also have an effect.
With nothing patched to the Accent CV input turning the Accent knob effects the pitch, as does the Res knob. Having them both at max produces the most pronounced pitch rise, meaning that each knob effects pitch and that their combined output effects it more than one of the knobs at max by itself.

Env Mod knob does not effect pitch.

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 5:35 pm

... Interesting, the previous is also true with the decouple switch in the coupled position.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 5:40 pm

ok, so this is all good information. im assuming the ACC->RES knob doesnt change anything? and just to verify, this is the oscillator of the x0xheart itself that is drifting, and its drifting up in pitch as you apply more accent or more resonance? im thinking there might be a problem around U12.
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 5:52 pm

guest wrote:
Sun Dec 20, 2020 5:40 pm
ok, so this is all good information. im assuming the ACC->RES knob doesnt change anything?
With the Accent knob at 0 the Res>Acc knob doesn’t effect pitch. But with the Accent knob at max and turning the Res>Acc knob up from 0 I get additional pitch rise.
guest wrote:
Sun Dec 20, 2020 5:40 pm
and just to verify, this is the oscillator of the x0xheart itself that is drifting, and its drifting up in pitch as you apply more accent or more resonance? im thinking there might be a problem around U12.
No, the pitch rise issue only happens when using the Ext input (Dixie II+ or other external oscillator). I get no pitch issues with the internal x0xheart’s oscillator.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 5:57 pm

is the pitch rise constant, or only at the beginning of the note? just to recap:

1. internal oscillator works fine
2. external oscillator drifts up with 1k, but not without 1k.
3. turning the accent knob up increase the pitch rise, with accent at 0 giving no rise
4. both ACC->RES and RES knobs increase the amount of pitch rise, but do not effect pitch if accent knob is at 0.

if you listen to the VCF out on the x0xheart, do you hear any pitch rise?
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 6:29 pm

guest wrote:
Sun Dec 20, 2020 5:57 pm
is the pitch rise constant, or only at the beginning of the note?
If the voltage to the Accent gate input is constant than the pitch rise is constant, if I feed the accent gate input a gate then the pitch rises up with each gate.
guest wrote:
Sun Dec 20, 2020 5:57 pm
just to recap:

1. internal oscillator works fine
Yes.
guest wrote:
Sun Dec 20, 2020 5:57 pm
2. external oscillator drifts up with 1k, but not without 1k.
Yes.
guest wrote:
Sun Dec 20, 2020 5:57 pm
3. turning the accent knob up increase the pitch rise, with accent at 0 giving no rise
Yes.
guest wrote:
Sun Dec 20, 2020 5:57 pm
4. both ACC->RES and RES knobs increase the amount of pitch rise, but do not effect pitch if accent knob is at 0.
Yes.
guest wrote:
Sun Dec 20, 2020 5:57 pm
if you listen to the VCF out on the x0xheart, do you hear any pitch rise?
Yes. It sounds like the same amount of pitch rise as I get coming out of the VCA output.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 6:52 pm

ok, im a bit confused as your answer to 1 and the very last question (the one after 4) seem to be contradictory. is there pitch rise on the x0xheart oscillator? if so does it change at all with time? listening to the VCF out allows you to hear the pitch after the note has decayed. also, another confirmation:

5. if you apply accent gate, but not note-on gate, then there is no pitch shift in the dixie or x0xheart VCF out (the dixie can recieve gate for this test)?
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 7:20 pm

guest wrote:
Sun Dec 20, 2020 6:52 pm
ok, im a bit confused as your answer to 1 and the very last question (the one after 4) seem to be contradictory. is there pitch rise on the x0xheart oscillator?
The x0xheart’s internal oscillator is not effected by the pitch rise issue. If I set the EXT/INT switch to external and adjust the Accent knob to max for the max pitch rise and then switch to INT the pitch rise goes away. This is the case for the VCA and VCF outputs.
guest wrote:
Sun Dec 20, 2020 6:52 pm
if so does it change at all with time? listening to the VCF out allows you to hear the pitch after the note has decayed.
If I slow down the tempo of the x0xb0x I can hear the pitch fall so yes, I think so.
guest wrote:
Sun Dec 20, 2020 6:52 pm
also, another confirmation:

5. if you apply accent gate, but not note-on gate, then there is no pitch shift in the dixie or x0xheart VCF out (the dixie can recieve gate for this test)?
But without the note-on gate the x0xheart doesn’t produce any output and the Slid CV output will just remain consistent, no?

Can you explain this set up with a little more detail? Sorry, I’m not getting it.

User avatar
guest
Super Deluxe Wiggler
Posts: 5584
Joined: Mon Aug 19, 2013 11:49 am

Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Dec 20, 2020 7:56 pm

there should always be sound at the VCF output on the x0xheart, whether it has a gate or not. so if you dont apply a gate, and listen to the audio at the VCF out jack, does the pitch change with accent? the slid CV out might change or it might not, im not sure, and thats what id like to know. is there some interaction with the gate-on that is causing the pitch shift, or is it entirely the accent causing the pitch shift?

so the x0xheart pitch falls with time, after the note is done playing? if you listen to VCF out, does the pitch match the dixie at the end but not the beginning?

VCF should be set to INTERNAL for all these tests.
openmusiclabs.com

morbank
Common Wiggler
Posts: 222
Joined: Sun Sep 15, 2019 12:08 pm
Location: California, USA

Re: EURO x0x-heart - Complete "Kit"

Post by morbank » Sun Dec 20, 2020 8:42 pm

guest wrote:
Sun Dec 20, 2020 7:56 pm
there should always be sound at the VCF output on the x0xheart, whether it has a gate or not.
Doh! Sorry, I had the Cutoff set low and couldn’t hear and sound at the VCF output.
guest wrote:
Sun Dec 20, 2020 7:56 pm
so if you dont apply a gate, and listen to the audio at the VCF out jack, does the pitch change with accent?
No.
guest wrote:
Sun Dec 20, 2020 7:56 pm
the slid CV out might change or it might not, im not sure, and thats what id like to know.
With the Slid CV output connected to my scope I don’t see any change in voltage when I add 5v to the accent Gate input.
guest wrote:
Sun Dec 20, 2020 7:56 pm
is there some interaction with the gate-on that is causing the pitch shift, or is it entirely the accent causing the pitch shift?
With the Slid CV output connected to my scope I don’t see any change in voltage when I toggle 5v to the Gate input.
guest wrote:
Sun Dec 20, 2020 7:56 pm
so the x0xheart pitch falls with time, after the note is done playing?
With the Slid CV output patched to the v/oct input on the Dixie and the output of the Dixie patched to my mixer and a repetitive gate sent from the x0xb0x’s gate out into the x0xheart’s Gate input I can hear the pitch fall after each note on. It sounds like the pitch follows the envelope voltage. Starts high at the gate on, then quickly falls until the next gate on.
guest wrote:
Sun Dec 20, 2020 7:56 pm
if you listen to VCF out, does the pitch match the dixie at the end but not the beginning?
If I set the x0xheart to C2 (VCF output set to INT) and the Dixie to C2 and then apply a constant 5v to the Accent Gate input with a repeating gate from the x0xb0x to the x0xheart’s gate input (the pitch rise only happens when I send gates to the x0xheart’s gate input) the pitch of the x0xheart rises up and is never in tune with the Dixie. But it’s closest in pitch with the Dixie at the end of each gate.
guest wrote:
Sun Dec 20, 2020 7:56 pm
VCF should be set to INTERNAL for all these tests.
Yes, all of the above tests were done with the x0xheart set to INT.

Post Reply

Return to “Music Tech DIY”