73-75 interference

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leftbracket
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73-75 interference

Post by leftbracket » Tue Feb 25, 2020 2:35 pm

I have noticed some interference between modules on my 73-75 Voice:

-The oscillators will bleed into each other's outputs when set to similar frequencies.
-When active, the envelope will always slightly affect the oscillators' pitch (by about a whole step).
-Turning a knob may slightly affect a parameter on another module.

My power adapter is grounded, and I have noticed these same problems regardless of what outlet is powering the Serge. Is this a function of poor power conditioning, grounding issues, or similar from the outlet affecting the unit's performance, or are there possibly problems with the Serge itself that are causing these interferences (or perhaps it's a "feature, not a bug" property of the earlier designs)?

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Clockgate
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Re: 73-75 interference

Post by Clockgate » Tue Feb 25, 2020 2:50 pm

I just checked my 73-75 voice panel, and there is no bleed between the oscillators, regardless of the pitch of either. Also, the envelope doesn't cause any interference in any of the modules.

The only thing I noticed is the right frequency CV control on both VCOs varies the pitch slightly when moved, even when nothing is plugged into the CV banana input. This is actually really useful, since it can act as a fine tuning control, which the VCOs don't have.

Are you sure the power supply you are using can supply enough current to power the panel comfortably?
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leftbracket
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Re: 73-75 interference

Post by leftbracket » Tue Feb 25, 2020 2:53 pm

My adapter is rated at 5A, which should be far more than enough for the panel.

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Clockgate
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Re: 73-75 interference

Post by Clockgate » Tue Feb 25, 2020 3:09 pm

Yes, 5A is well above what the panel would consume.

Is this a shop built panel, or DIY?
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leftbracket
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Re: 73-75 interference

Post by leftbracket » Tue Feb 25, 2020 3:14 pm

Clockgate wrote:
Tue Feb 25, 2020 3:09 pm
Is this a shop built panel, or DIY?
Shop-built.

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beatcleaver
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Re: 73-75 interference

Post by beatcleaver » Tue Feb 25, 2020 3:20 pm

leftbracket wrote:
Tue Feb 25, 2020 3:14 pm
Clockgate wrote:
Tue Feb 25, 2020 3:09 pm
Is this a shop built panel, or DIY?
Shop-built.
there are shop built panels for these? I thought they were all DIY.

Did the original designer offer built panels, or is this a third party store building these to the published DIY specs?

leftbracket
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Re: 73-75 interference

Post by leftbracket » Tue Feb 25, 2020 3:21 pm

beatcleaver wrote:
Tue Feb 25, 2020 3:20 pm
leftbracket wrote:
Tue Feb 25, 2020 3:14 pm
Clockgate wrote:
Tue Feb 25, 2020 3:09 pm
Is this a shop built panel, or DIY?
Shop-built.
there are shop built panels for these? I thought they were all DIY.

Did the original designer offer built panels, or is this a third party store building these to the published DIY specs?
https://shop.73-75.com/voice

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beatcleaver
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Re: 73-75 interference

Post by beatcleaver » Tue Feb 25, 2020 3:26 pm

leftbracket wrote:
Tue Feb 25, 2020 3:21 pm
beatcleaver wrote:
Tue Feb 25, 2020 3:20 pm
leftbracket wrote:
Tue Feb 25, 2020 3:14 pm
Clockgate wrote:
Tue Feb 25, 2020 3:09 pm
Is this a shop built panel, or DIY?
Shop-built.
there are shop built panels for these? I thought they were all DIY.

Did the original designer offer built panels, or is this a third party store building these to the published DIY specs?
https://shop.73-75.com/voice
doh! not sure how I missed that, cheers.

I guess I'd contact the shop if I were you. I wouldn't expect this kind of bleed from a properly built panel. Best of luck.

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Clockgate
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Re: 73-75 interference

Post by Clockgate » Tue Feb 25, 2020 3:30 pm

Some good info on the 73-75 panels here:

viewtopic.php?f=19&t=194092&start=25

The shop built panels are great value, when you add the cost of parts and time onto the DIY prices. I usually DIY but bought a pre-built voice panel for that reason.
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beatcleaver
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Re: 73-75 interference

Post by beatcleaver » Tue Feb 25, 2020 3:52 pm

Clockgate wrote:
Tue Feb 25, 2020 3:30 pm
Some good info on the 73-75 panels here:

viewtopic.php?f=19&t=194092&start=25

The shop built panels are great value, when you add the cost of parts and time onto the DIY prices. I usually DIY but bought a pre-built voice panel for that reason.
cheers. Todd's video shows these are the real deal. The waveshaper demo and that fm part at the end sound very familiar.

It does look like great value if they're built well. Two oscillators, wave shaper, filter, ring mod, envelope, vca in a boat for under a grand. Besides second hand, DIY CGS panels I wouldn't have thought I'd see a serge panel at that price.

Are these known for being decently put together or too soon to tell?

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Clockgate
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Re: 73-75 interference

Post by Clockgate » Tue Feb 25, 2020 4:01 pm

beatcleaver wrote:
Tue Feb 25, 2020 3:52 pm
Clockgate wrote:
Tue Feb 25, 2020 3:30 pm
Some good info on the 73-75 panels here:

viewtopic.php?f=19&t=194092&start=25

The shop built panels are great value, when you add the cost of parts and time onto the DIY prices. I usually DIY but bought a pre-built voice panel for that reason.
cheers. Todd's video shows these are the real deal. The waveshaper demo and that fm part at the end sound very familiar.

It does look like great value if they're built well. Two oscillators, wave shaper, filter, ring mod, envelope, vca in a boat for under a grand. Besides second hand, DIY CGS panels I wouldn't have thought I'd see a serge panel at that price.

Are these known for being decently put together or too soon to tell?
The build quality on my shop built panel is excellent, and it was setup pretty good too, tracking over a few octaves. Definitely a no-brainer at that price, I am absolutely delighted with it.
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tele_player
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Re: 73-75 interference

Post by tele_player » Wed Feb 26, 2020 12:09 pm

I assembled one of these a few weeks ago, and I’m not seeing any of these symptoms.

kroffe
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Re: 73-75 interference

Post by kroffe » Thu Feb 27, 2020 3:20 am

I also got the factory built voice panel, but have zero problems. Have you contacted Jon a k a THC?

The fine-tune feature is actually by design I think.

leftbracket
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Re: 73-75 interference

Post by leftbracket » Thu Feb 27, 2020 8:10 am

Thanks all for your help. I will reach out to Jon today.

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