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Two Chroma Polaris newbie questions

Two Chroma Polaris newbie questions

2012-09-13 by w.james.meagher@gmail.com

Hello,

Two quick questions after having played my Polaris for about ten minutes since buying and repairing it:

1. Is everyone else's headphone jack quite noisy?

2. Is there a hardware reason (impossible by design) why you can't select Saw and Pulse simultaneously on a single oscillator, or is this merely limited by the OS programming?

Cheers,
James

Sent from my iPhone

RE: [chromapolaris] Two Chroma Polaris newbie questions

2012-09-13 by Paul D. DeRocco

> From: w.james.meagher@...
>
> Two quick questions after having played my Polaris for about
> ten minutes since buying and repairing it:
>
> 1. Is everyone else's headphone jack quite noisy?

Yes. A replacement output board that fixes the nasty noise problems in the
Polaris should be available in the not too distant future.

> 2. Is there a hardware reason (impossible by design) why you
> can't select Saw and Pulse simultaneously on a single
> oscillator, or is this merely limited by the OS programming?

When you select Saw, you are actually getting the saw plus the pulse. If you
want only the saw, set the pulse width to zero. The saw and the pulse are
combined such that they produce a shape that is equivalent to two
phase-shifted saws added together. (A pulse can be thought of as two
phase-shifted saws subtracted.) The result is the inverse spectrum of the
pulse by itself. Set the width to midscale, and the pulse gives you only odd
harmonics (a square wave), while the saws shape gives you only even
harmonics (a sawtooth an octave up).

--

Ciao, Paul D. DeRocco
Paul mailto:pderocco@...

Re: [chromapolaris] Two Chroma Polaris newbie questions

2012-09-14 by w.james.meagher@gmail.com

On 2012-09-13, at 4:48 PM, "Paul D. DeRocco" <pderocco@...> wrote:
 

> From: w.james.meagher@...
>
> Two quick questions after having played my Polaris for about
> ten minutes since buying and repairing it:
>
> 1. Is everyone else's headphone jack quite noisy?

Yes. A replacement output board that fixes the nasty noise problems in the
Polaris should be available in the not too distant future.

Damn, and I promised you I'd stop harping on about the replacement output board. Even knowing about the Polaris's noisy outputs I was a bit surprised at just how noisy my headphone output is. Once I get a replacement high output jack soldered in I'll be able to hear whether it's any better than the headphone jack.

> 2. Is there a hardware reason (impossible by design) why you
> can't select Saw and Pulse simultaneously on a single
> oscillator, or is this merely limited by the OS programming?

When you select Saw, you are actually getting the saw plus the pulse. If you
want only the saw, set the pulse width to zero. The saw and the pulse are
combined such that they produce a shape that is equivalent to two
phase-shifted saws added together. (A pulse can be thought of as two
phase-shifted saws subtracted.) The result is the inverse spectrum of the
pulse by itself. Set the width to midscale, and the pulse gives you only odd
harmonics (a square wave), while the saws shape gives you only even
harmonics (a sawtooth an octave up).

Wow... I felt like this was maybe a stupid question, but I sure am glad I asked it. Either I was sleepy when reading it, or the OM didn't do a very good job of explaining this - but your explanation sure explains why my ears were contradicting my expectations while playing with the OSC settings.

Thanks again Paul!

Cheers,
James