Casio CZ/ VZ/ FZ - Pro Series

Thanks Lee. Karl May

________________________________

From: CZsynth@yahoogroups.com [mailto:CZsynth@yahoogroups.com] On Behalf
Of Lee Borrell
Sent: Tuesday, 6 October 2009 9:29 PM
To: CZsynth@yahoogroups.com
Subject: Re: [CZsynth] Re: Any Mods to Make CZ101 Quieter


  

That sounds like the ADSR signal is getting into the audio signal -
could be some sort of a short circuit or maybe a failed or about to fail
component?

--- On Tue, 6/10/09, karl452055 <kmay@...
<mailto:kmay%40brayecragg.com.au> > wrote:

From: karl452055 <kmay@...
<mailto:kmay%40brayecragg.com.au> >
Subject: [CZsynth] Re: Any Mods to Make CZ101 Quieter
To: CZsynth@yahoogroups.com <mailto:CZsynth%40yahoogroups.com> 
Date: Tuesday, 6 October, 2009, 2:06 AM

  

--- In CZsynth@yahoogroups .com, "tomulcahy" <tomulcahy@. ..> wrote:
>
> If the buzz is there when you're not playing sounds, then it's not the
DAC. It's some sort of grounding issue. Does it happen with the line
output also?
> 
> I've definitely seen the CZ-1000 service manual around for download,
just can't remember where :( But I would say that you could safely refer
to the CZ-1 service manual for DAC offset in the 101.
>
Thanks Tom.

The hum in my CZ101 appears at both line out and headphone out. It is
there when no sound is being played. It is not affected by the volume
control. The level of the noise stays the same no matter where the
volume control is set.

I've tried changing the power supply to no effect.

The noise seems to be made up of three separate frequencies.

The bottom frequency appears to be AC hum.

The next frequency is higher and is a buzzing sound.

The highest frequency is an oscillating sound.

Something interesting happens when I play a sound. Immediately after I
release the keyboard key the middle frequency sound rises in frequency
momentarily, then falls back to the original frequency.

Any thoughts anyone,and thanks to everyone.

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