#8

Is it a high frequency noise?

I fixed this with with a second hand Switch but that silencer looks really interesting.

Another tip I got from Brian was to change the capacitors if the 2015 grid has the old ones which should reduce the noise (though probably not completely) 2015 grid noise fix

Also someone on this forum may have an old Ext 5v they could sell you which may also do the trick.

#9

just ordered the m05 silencer… thanks for this tip! – i’ll keep you guys posted when i receive it.

thanks @jasper_ryder, too! i wasn’t aware of this… will check my monome to see if it’s a faulty one.

#10

Provides 5 Volts

Just a word of warning, without knowing the details: I’d be cautious with that if you already have 5v in your rack.
I damaged my monome trilogy modules by inserting a mutable volts regulator into a case that already had 5v… (hidden documentation of the cell series, yay). Hopefully I’m overreacting here…

Edit: Ansible doesn’t draw from 5v, so it should be safe. But others in the rack might (?)

Also: ext5v should be open sourced somewhere IIRC

2 Likes
#11

well, judging by my bad eyes, my capacitors do look like the non-noisy ones… narrowing down the problem – can anyone confirm this?

for reference, here’s a recording of the noise (first with no grid plugged in, then with idle grid and finally jumping through submenus / more LEDs): https://www.dropbox.com/s/lgiyiop7oba94c1/monome%20humming.wav?dl=0

unnamed-2.jpg750×1000 79.6 KB

#12

these are the correct caps.

keep in mind the ansible draws all power from the 12v line, re trogtronic.

i’m sorry that there is so much trouble when it comes to matching a power supply with these modules.

one solution to check is to ground-lift the ACDC power brick for your power supply-- often the noise is ground related if you’re connecting to a grounded mixer or set of speakers.

another solution is to offload the USB power using either a Switch, ext5v-- both of which we’re out of-- i’m sorting out a new/better solution. one of which is this thing:

(edit: removed link prior to testing)

basically it provides external power to two devices. external power comes from a usb power source as well, so no voltage issues-- and you can use an iphone-style charger which are ubiquitous. this thing isn’t mountable, it’s just a dongle. we can design some mountable versions or different configurations quite easily. also this one doesn’t switch. it’s just power isolation for two devices, ie grid+arc

1 Like
#13

hei brian, thanks a ton for jumping in! … i’d like to give this ^^ a shot – can you tell me how to do so (or where to find out)? eurorack and power are quite new to me… i recall having read that it’s not ideal to have an ungrounded power supply (such as the 4ms row powers).

would something like this work, or am i on a totally wrong page?

White Whale vs Ansible vs Meadowphysics
#15

a few troubleshooting results using arc + ansible + intellijel tps80w

  • ground lift on the intellijel/meanwell power brick did not remove the noise

  • ext5v added between arc + ansible (no ground lifts at all) did not remove the noise

  • ground lift added to ext5v power brick, noise gone!

so it seems that externally powering the grid / arc and removing it from the shared ground path is the solution. i’ve heard that ground lifting is hazardous, but i’m assuming that because i’m only lifting the arc (as opposed to my higher voltage, semi-exposed eurorack bus) and it’s circuitry is well hidden i’m probably not exposing myself to much risk.

for those wondering, my ground lift looks like this:

one more data point:
the intellijel tps80w has tons of 5v. i’ve tried running trilogy modules directly to the grid without switch or ext5v. the noise is there, too.

@tehn is that oshpark board ready to go or should we wait for further testing?

i should also note that this noise isn’t terribly loud on my setup. when i have a full piece with many voices running it’s not noticeable. it’s those quiet moments where it stands out. fine for live stuff, but not so much for recording.

4 Likes
Meadowphysics (ansible) / triggering single steps on other rows?
#16

i have the PCBs at the workshop but haven’t built one to test. conceivably they should work given they are so simple. i can also send you one when i get back (oh and hey i’m in the bay area!)

i like the idea of the external power source also being USB, because almost all USB power supplies (ie iphone etc) are two prong and very universal-- plus you could use a USB battery if desired for maximum isolation.

1 Like
#17

@shellfritsch @benniii,

Sounds like if it’s a grounding issue the m05 silencer wouldn’t make a difference?

#18

@tehn yeah this sounds promising. enjoy the bay!

@jasper_ryder without knowing what’s going on inside that m05 silencer it’s hard to say…

1 Like
#19

well, if the m05 only fixes the 5v line, which the ansible doesn’t touch, i don’t think it’d help. would be good for trilogy modules.

1 Like
#20

Hi! I am definitely in the boat where I get a nasty hum when I connect the grid to Ansible. To be honest, I almost wouldn’t notice it so much, but I can hear it hum when nothing is plugged in. I’d love to be able to perform, or even play really quietly without that tinnitus-esque feeling. My case is a TipTop Mantis, and it’s theoretically grounded, but I believe that none of the three-pronged outlets in my apartment are actually grounded. :zap:!

Does anyone have any suggestions for powering the grid separately to avoid this issue? The USB splitter seems like a good idea, but a nightmare for cable management.

#21

i just learned about the aturia-made “anti ground loop adapter” from a friend with a beatstep pro. i guess the leds in the bsp have been known to bleed into the cv connections.


(y-cable on the left)

unfortunately it can only be purchased as part of a 4 piece replacement cable kit.
i haven’t tested this out with my grid, but seems like it could be an alternative for folks who don’t want to build the offworld adapter.

1 Like
#22

The beatstep pro ground loop adapter is all usb c so there would be some cable adapters involved here.

#23

did they post anything about the actual internal functionality of these cables?

#24

i haven’t seen anything that specific.
all i have to go off of are multiple accounts of “it works” and this from the bsp manual:

Something to consider : Ground loops
A ground loop is an unwanted current in a conductor connecting two points. The result is
noise in your audio signal, usually in the form of a low-frequency hum. In setups
including computers, interfaces and audio devices, it’s possible to end up with an
annoying ground loop. We have provided you with a solution, however: the anti ground
loop adapter.

When should I use the anti ground loop adapter?

In most cases you will not need the anti ground loop adapter.

If you don’t have a ground loop problem in your setup, simply connect the BeatStep
Pro with the supplied USB cable to a computer or a USB power supply.
You should use the included anti ground loop adapter if you experience background
noise in your speakers that disappears when you disconnect the audio interface from
your computer or the CV/Gate connections to your analog gear. A ground loop can also
cause problems with pitch tracking when using the BeatStep Pro CV connections with
analog synthesizers.

#25

just found this:

#26

good find.

so they dropped mad $$$$ to make a plastic molded version of the “offworld” pcb essentially. would be great if they sold this bit separately.

1 Like
#27

So with this connector I can power my grid or arc externally?
I just got a beat step pro in the post yesterday, and i have been suffering a bit from noise when plugging in my arc, but can i just plug my cable from ansible to “pc”. And then power to pwer (of course…), and my arc or grid, through an adapter, to the male end of the beatstep pro cable? This would be the way to go right?
I have an adapter coming, I will be able to try it monday or tuesday and see if it works.

#28

It’s micro usb-b, not usb-c, but yes adapters is needed

1 Like
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