EURO x0x-heart - Complete "Kit"

[morbank]

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?

[guest]

with the 1k.

[morbank]

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.

[guest]

ok, so leave the switch in the decouple position.

[morbank]

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.

[guest]

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?

[morbank]

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]

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]

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

[morbank]

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.

[guest]

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?

[morbank]

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?

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.

[guest]

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

[morbank]

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?

[guest]

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.

[morbank]

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]

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

[guest]

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.

[morbank]

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.

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.

[guest]

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?

[morbank]

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.

just to recap:

1. internal oscillator works fine

Yes.

2. external oscillator drifts up with 1k, but not without 1k.

Yes.

3. turning the accent knob up increase the pitch rise, with accent at 0 giving no rise

Yes.

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.

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.

[guest]

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)?

[morbank]

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.

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.

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.

[guest]

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.

[morbank]

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.

so if you dont apply a gate, and listen to the audio at the VCF out jack, does the pitch change with accent?

No.

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.

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.

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.

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.

VCF should be set to INTERNAL for all these tests.

Yes, all of the above tests were done with the x0xheart set to INT.