An odd noise source!

[shredd]

Hi kidz...
I've got sort of any odd noise-intrusion issue I haven't been able to get a handle on. I've been fussing with it for ages, feel like I've tried everything. Wanna bounce it off you smart guyz.

In my little 'studio' (yeeeess, it was a spare bedroom) - I've got an iMac (hiding off to the left of the Rolands) that serves some peripheral duties, primarily giving access to G/Band and playing its' instruments/plugins.
I have my Roland JD-Xi USB'd into it as a controller to play the instruments.

My problem is that when the computer is on, there's a loud, nasty electrical/interference noise leaking into my system.
After muuuuch cable-swapping/pulling, etc, I've isolated it:
When I pull the USB cable connecting the JD-Xi to the iMac, the sound goes bye-bye. I've tried several USB cables, but it's not the cable: clearly the JD-Xi is producing noise in its' USB-MIDI output/connection, or the iMac is making it by having the Roland connected to it. They aren't playin' nice together.

Wassup with that? Any solutions?
My first instinct was to simply acquire a different MIDI controller/KB that I can 'USB' into the iMac. The only reason I haven't done that is that I have NO way of knowing if it'll work, and I don't wanna spend the pile of bux it'd take just to find out. I don't know anyone I can borrow one from to try.
Anyone have any other ideas?

 

[-mjk-]

@shredd you should try getting a couple of snap on chokes and putting them in line in the cable. you can also source an RFI shielded, USB cable, and if you really wanna go all out, they are USB connector boxes that are designed to filter extras RF on USB signals.

 

[shredd]

Thanks @-mjk- ; I'll look around for the chokes (I don't have a cable with the right ends that has one..).
Any leads on these USB connector-boxes w/RF filtering? Where would I look for something like that? Sweetwater? NSA? NASA?!?

EDIT:
Never mind. Took my own (usually snarky) advice and googled it...found some sources. Except they're all US$50 and up!!!
Might haveta give the snap-on chokes a go, to see if it resolves, before I go with new MIDI cont'r...looked in ebay, and can only buy large lots of them - I just need the one, to try...sigh...
THNX

 

[mixerizer]

I swear by these. I use them on all my ‘problematic’ usb midi / audio hardware (Roland GI-20 guitar-to-midi converter, Yamaha P-125 piano, Roland SPD Octapad). They removed a bunch of weird noise from my system that seems related to changes in onscreen graphics, hard drive access, mouse movements, etc - all seemingly caused by a ground loop which introduces bad EFI on the USB.

Note like you, I do not use the USB for audio, just midi. There is a faster version, the G01B, which might work for noise interference over audio USB.


DSD TECH SH-G01A USB Isolator with ADUM3160 Chip 12M (Blue)
https://www.amazon.com/gp/product/B093LKN3YH

 

[shredd]

THNX @mixerizer - will DEF'Y be checking that out.

 

[mixerizer]

No worries! That should give you an idea of the range of options - as mjk said, there are cables, chokes n boxes n all kinds of solutions (at all kinds of price ranges). Good luck!

 

[shredd]

Yeesh...
I realize that truly understanding and configuring/implementing MIDI is comparable to operating the Higgs-Bosun collider...and meatheads like me are lucky when I can even remember what "MIDI" means...

But this one stumped me:
I was all ready to order up one of the Isolators @mixerizer had suggested - sounded like just the ticket.
Today, I was in the studio with the iMac on, 'cuz I was foolin' around with something in G/Band. I had unplugged the USB to the Roland 'cuz I didn't want to be bothered by this awful noise problem.
After about 1/2 hour, I wanted to experiment with some sounds in G/Band, and needed the Roland to be the controller.
So I plugged it back in; there was a brief notification on the screen that I barely saw - it said something about "you have opened a new MIDI port" or something like that...
And the noise is GONE.

So I guess even a brain-dead drooling moron like me can operate MIDI (even if by accident)?!?

 

[mixerizer]

Hehe - well if you aren’t certain of the cause of a problem, it’s hard to be certain it’s solved - but enjoy the low noise floor (for now?)

I’m glad to say my USB noise problem (which was also intermittent) has not recurred since I plopped those inexpensive little guys on the instruments in question. It was annoying enough, and affected the sound enough that I was getting ready to spend more if I had to.

 

[shredd]

Yeah, I definitely considered that this was a temporary respite - that if the iMac assigned the problematic MIDI channel to the Roland again, the noise would be back...
So I might end up with one of those little guys on the USB cable anyway.
But for the time being, I'll enjoy it. I don't use the iMac that much anyway, at least for G/Band or music use, as much as I do file management/backup...
But I'm trying to bring G/B back into my workflow again - it's pretty handy and enables doing stuff that's harder to do in real life...

 

[mixerizer]

GarageBand was my pal during years of straight-to-laptop DAW songwriting when the physical and emotional weight of managing and reconciling all the big-ticket DAW studio gear was getting me down.

I got over my funk w some of this better TASCAM gear

Most of all, enjoy the quiet noise floor!

 

[-mjk-]

@shredd over the next few sessions, try your un/plug routine and see if it works. If so, I can be part of your workflow and just move on.

 

[shredd]

try your un/plug routine and see if it works

Weelllll...I've got my answer to this: fired up the studio gear today to work on sumthin' and...yup...there's that noise.
SO - I just unplugged the Roland's USB-to-iMac cable (sound disappeared at once) and carried on...

Now...if I ever haveta use the Roland as a controller for the G/Band instruments...I can just plug it in and ignore the noise (it does NOT come through on recorded tracks/takes - just a byte to listen to...).

Might still take a crack at @dctdct 's cable-plug doodad. I gotta feeling that would do it...but I spent my couch-change this week on having Elton John over for nachos and cocoa, and tracking piano parts for an EJ cover, since he plays a good bit better than I do...

 

[-mjk-]

@shredd, consider yourself fortunate. This is really just as extension of a necessary start-up routine. Most studios require equipment to be brought online in a specific order. You found the solution and it's really quite simple.