x0x 122 tuning.

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hamburgers
 
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x0x 122 tuning.

Post by hamburgers »

Aside from the broken accent pot (my fault), my tuning seems to be off.

I have my x0x in tune with the tuning knob all the way to the left, which is where I tend to leave it. My low C is in tune with a C on several other synths, but when I press they high C in keyboard mode it gives me a B. It seems I don't have a full octave range.

???
:(

Jonnay
 
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Post by Jonnay »

TM5 needs to be adjusted perhaps?

I recall reading something while ago about their x0xb0x not being 100% in tune, especially on the higher notes.

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hamburgers
 
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Post by hamburgers »

Well I tuned it to my other synths using the trim pots, but even when I get one key in tune, that same key the next octave up or down remains out of tune! I'm getting an 11 note range rather than 12.

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chairman meow
 
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Post by chairman meow »

mome rath wrote:I have my x0x in tune with the tuning knob all the way to the left, which is where I tend to leave it. My low C is in tune with a C on several other synths, but when I press they high C in keyboard mode it gives me a B. It seems I don't have a full octave range.
I believe that Limor's stock 1.03 firmware has an off-by-one-note but in MIDI PLAY mode. KEYBOARD mode does not; however since LEDs don't light for either mode, nobody noticed unless they were really paying attention. Bug is described on SourceForge and this thread.

If you're comparing notes in only one mode, ie. hitting C then C' in keyboard mode, and don't hear a full octave, then you're just plain out of tune. Verify that your power supply is giving exactly 5.33333V, re-check your VCO circuit, do a rain dance.

If you have nother synth connected via MIDI, hit C on the x0xb0x keyboard and get a C from your other synth, but hit C on the other synth and get a B from the x0xb0x, you're seeing the bug I described. You should either install my latest firmware, or bug Limor to use my patch.

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Post by Guest »

Chairman Meow wrote:
mome rath wrote: If you're comparing notes in only one mode, ie. hitting C then C' in keyboard mode, and don't hear a full octave, then you're just plain out of tune. Verify that your power supply is giving exactly 5.33333V, re-check your VCO circuit, do a rain dance.
It goes between 6.08 and 6.54 at either extreme of the potentiometer 8)

hooray for out of tune

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subatomic
 
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Post by subatomic »

mome rath wrote:Well I tuned it to my other synths using the trim pots, but even when I get one key in tune, that same key the next octave up or down remains out of tune! I'm getting an 11 note range rather than 12.
sure it isn't your octave width trimpot?

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hamburgers
 
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Post by hamburgers »

I posted the voltage issue when I first started building the PSU. Unfortunately, may lack of patience combined with slow responses resulted in me just building the whole damn thing and dealing with it.

But now that I'm trying to use it in proper tracks, the tuning is a bit of a problem. It's alright if I just program it by ear and then play along, but somewhat of a nuisance nonetheless.

Anyway, which is the octave width TM? I tweaked 'em all, one by one and in combination, but to no avail. And I was wrong, low C doesn't tune to B. It tunes to C#`. Either way, I'm still unsure as to how to solve this. I began to test voltages across components in the PSU as Jonnay suggested, but there was no followup because I just ejaculated "122 WORKS THERE IS NOISE ZOMG" and that was that.

(Jonnay if you're reading this plz help meh :( )

DiscoVolante
 
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Post by DiscoVolante »

mome rath wrote:I began to test voltages across components in the PSU as Jonnay suggested, but there was no followup because I just ejaculated "122 WORKS THERE IS NOISE ZOMG" and that was that.

Did you ejaculate on the x0xb0x? Because that could be your problem right there.

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subatomic
 
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Post by subatomic »

mome rath wrote:Anyway, which is the octave width TM?
The fab manual says how to tune up your box to "official Roland spec". There's 3 trim pots, 2 in the vco and 1 for the res.
My box sounded like BANNED until I performed this tuning...

You can use guitar tuner, oscilloscope, or your ear...

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Post by Guest »

DiscoVolante wrote:
mome rath wrote:I began to test voltages across components in the PSU as Jonnay suggested, but there was no followup because I just ejaculated "122 WORKS THERE IS NOISE ZOMG" and that was that.

Did you ejaculate on the x0xb0x? Because that could be your problem right there.
I knew the first time I tried to use that term it would end in tears!

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hamburgers
 
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Post by hamburgers »

Oh Jonnay why hast thou forsaken me? :cry: :oops:

Jonnay
 
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Post by Jonnay »

nothin personal.

Actually, I am not the guru that everyone thinks I might be...

Anyway, if your PS is not outputting the correct voltage (5.333) then you just arn't going to be in tune. I think (but don't know) that the 5.333 volts is important for the exponential converter. Also, your saw waves are going to be messed up and probably in the wrong shape, which menas your square is going to be wrong... and we haven't even left the VCO! the 5.333 volts is also important for the filter I think.

Also, the 5.333V is responsible for generating your 12V power sourcce via an opamp and voltage multiplier. If your voltage is 6.08V, then your 12 V is actually 13.375, instead of 11.732 V (ideally). So you are about 1.6 V off. I don't know if that is a big deal, I suspect not, but you might be saturating, or oversaturating your trannies.

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hamburgers
 
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Post by hamburgers »

After a bit of cogitation on this matter I realized that the tuning was not off until I ripped the BANNED open to do the bass boost and resonance mods (and broke the accent).

I guess there is a fair amount of rain dancing to do either way. BTW bass boost mod made it just fart noise at me for some reason so I pulled it out... and the resonance boost didn't work either. Buuuut, futzing around with one of those trim pots gave me higher resonance. Wish I'd just done that before I guess!

:oops:

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hamburgers
 
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Post by hamburgers »

Tuning fixed by careful trimpot tomfoolery. Accent fixed via new pot.

and it was good

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