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SEQUENTIAL/DSI => Tempest => Topic started by: hessel on August 19, 2019, 08:59:32 AM

Title: Weird distortion effect on every 3rd beat
Post by: hessel on August 19, 2019, 08:59:32 AM
Hi,

I have and issue and hope some of you can enlighten me. When I make a simple 4/4 beat, I notice some high pitched note on every 3rd sound in a beat. It's hard to describe, so I made a recording where the sound comes into play after 3/4 seconds:

https://clyp.it/jprc2p22

I have noticed the sound becomes harder when I increase the distortion, which makes me think it has something to do with that.

I really hope someone can explain it to me and I don't have any hardware issue  :-\

To be sure; in the example above I initialized a beat and the 1 sound you hear. It's the default Hollow thud sample. I only increase the distort knob to make the sound more clear. The sound is recorded from the main outs, but the issue is the same when I listen via headphones.
Title: Re: Weird distortion effect on every 3rd beat
Post by: Yorgos Arabatzis on August 19, 2019, 02:25:55 PM
Main OS version?Voice OS version?
Have you tried calibrating with all cables unplugged?
Title: Re: Weird distortion effect on every 3rd beat
Post by: hessel on August 20, 2019, 02:35:22 PM
Main OS version?Voice OS version?
Have you tried calibrating with all cables unplugged?

Yes, I double checked the OS versions and calibrated the oscillators and filters.

The sound is removed when I decrease the default level of decay...
Title: Re: Weird distortion effect on every 3rd beat
Post by: and-shee on August 27, 2019, 02:56:48 PM
Hi Hessel,

 I had this same issue, and it seemed to be a ribbon cable inside the Tempest causing interference on voice 3. I found out as I decided to investigate and ended up adding a sticky foam pad to the ribbon cable to give it a little distance between the base PCB which seemed to solve the issue. I also got in touch with customer support about it, who confirmed that it was indeed just noise from the cable.

Quote
The issue is likely related to the ribbon cable which connects between the two front panel boards. When the ribbon cable is not seated properly against the boards, it hangs over the circuitry of voice 3 and induces noise into the voice.

Opening the Tempest and tucking the ribbon cable in is an easy procedure which requires only a screwdriver to perform.

The instructions are as follows:


- First unplug all audio/MIDI/USB/power cables.
- Unscrew the 6 screws along the back plate and the 7 screws on the bottom panel of the Tempest. The front panel is now removable.
- Place a soft piece of material directly behind the Tempest (bubble wrap, blanket, towel, etc...). Lift the faceplate away from you towards the rear of the unit and set it face down on the soft material.
- Remove and reseat the ribbon cable between the panel board and the pad PCB board. Remove the Ribbon cable by rocking the connector back and forth with medium force. DO NOT PULL the ribbon cable itself. Pay special attention to this ribbon cable, it must remain slightly tucked under the front panel PCB with a bend or you may get crosstalk (noise) on voice 3. (see attached image for how the cable should sit against the boards and be tucked between them.
- Reassemble the Tempest in the reverse order of disassembly.
Once you've tucked the cable back in, check whether the noise you noted on voice 3 is still present or not.

Hope this helps!

Andy
Title: Re: Weird distortion effect on every 3rd beat
Post by: hessel on August 31, 2019, 03:40:51 AM
Hi Hessel,

 I had this same issue, and it seemed to be a ribbon cable inside the Tempest causing interference on voice 3. I found out as I decided to investigate and ended up adding a sticky foam pad to the ribbon cable to give it a little distance between the base PCB which seemed to solve the issue. I also got in touch with customer support about it, who confirmed that it was indeed just noise from the cable.

[...]

Hope this helps!

Andy

Hi Andy,

Thanks for your reply! Really appreciate it.

I opened the Tempest and tried to remove the ribbon cable connector, but it looks impossible to move. Also, the ribbon cable feels quite sturdy, so I don't know what good it will do one I remove it.

What worked for you is just adding a tiny piece of sticky foam to the middle of the ribbon cable? Do you by any chance have a picture of it saved?

See the attached image to this post for my current situation.