Plonk noise


Has anyone had any issues with noise from the Plonk module in a case? I got a Blackhole Six case, 60 hp wide with a Konstant Lab Board PWR supply and the Plonks are notably noisier. I have been working the last three days trying to find the culprit, and after moving the Plonk into an Intellijel case and running its audio into the Blackhole case - the noise is gone.

Does anyone have any suggestions on what to do? Is this just sort of a ‘you’re fucked!’ sort of scenario?

Now accepting any and all help :slight_smile:

It may just be a noisy Plonk. Emailed support earlier to sort out how to get these fixed or troubleshoot. So messy trying to isolate problems.

Noise issues can be tricky to isolate and resolve, but the best way is to be systematic about it.

What are you using as your output stage? Are you using balanced cables? Does the wall outlet or power bar that you have the case plugged into make a difference?

From your description it would seem like the intellijel PSU is possibly providing better filtration and ground isolation than the Konstant Lab power board. I have never used or inspected the Konstant lab psu so I can’t really comment on it. You might get different results by plugging it in to different power sockets on the Konstant lab board since this will change the impedance of the ground return from the Plonk module via the ribbon cable.

I’ve tried multiple power supplies and cases: Monorocket late-era 104, Intellijel 4U84 and 4U42, and a Blackhole SubSix with an Intellijel mini PSU. Noise in all of them. I’ve removed everything else from the signal flow. I even tried an external filtered bus board that my friend loaned me. Tried multiple sockets on each of these supplies. Listened to my mixer/monitor combo with other signals and the noise isn’t there.

I’m pretty confident after almost a week of troubleshooting that it’s one or both of the Plonks. I’ve been talking to Avery who has been helpful. Hoping to get these sent to you all to look over them and test them with fancier equipment than I probably have and way more electrical engineering knowledge than I certainly have.

I really hope these can get fixed (and quickly) because a handful of shows (including Vancouver!) this summer was theoretically going to include this mini-case with two Plonks as the starting sound source for everything. Now…who knows…I pondered a Plaits as a replacement, but just not confident it’ll be adequate for what I’m trying to do with the Plonk.

Thanks for the responses guys, I appreciate your help.

I use MDLR case busboards exclusively and I occasionally have problems with noise when my 2 Plonks are installed. The reality is that it’s probably not the Plonk unit that is the issue, it’s just that it’s a digital module with a significant power draw. A single plonk with a series of analog modules on the same board produces no noise, but several digital modules installed on the same board will. A recent example of this for me: I have 2 plonks in one rack with morphagene and mimeophon. With just those installed there is no digital noise. As soon as I add an digital filter Sqwk Dirty the noise becomes audible. So in some sense it has to do with the whole installation rather than the Plonk itself. I will say that the power draw for 1 plonk is significant on the -12v, but that’s the price for them sounding so amazing. This is the exact rack I am referring to: I have 2 independent busboards and power bricks in this rack so that the ES9 and Performance mixer are isolated from the digital units.

Old thread but a revival; Plonk produces a high pitched sustained ‘sqeal’ which can bleed into the case/system. It also bleeds into its own output path. I have multiple intellijel modules and 3 7U cases; plonk is the only module that is poop for this reason alone. It’s too bad.

Isolating digital modules is indeed key to avoid bleed to other modules especially VCA’s but the module itself still produces the sqeal even when isolated. It’s not a broken unit as many digital modules (especially those with OLED screens) produce an audible sqeal. Morphagene does it as well as an example of another brand with the same issue. The engineering side requires additional filtering which adds to cost.

My module was returned and they acknowledged it had an unusually high level of noise and replaced or recalibrated it.