Looptimus buzz / hum with Midi Out into Strymon TimeLine

Looptimus

fynn

over 6 years ago (edited)

Hey guys, I received my Looptimus a couple of weeks back, and also just received my Midi cables from Best Tronics to allow me to plug it into my Strymon Timeline. When I plug the Midi cable from the Looptimus into the Timeline (Midi In port), all of a sudden, a loud buzz / hum starts coming out of my amp / speaker. The Looptimus is also plugged into my computer via USB. It sounds like electrical hum perhaps from a power source, but no matter what I do, I can't get rid of it. Has anyone had this issue before, and any ideas on how to resolve it? It pretty much makes the Looptimus unusable for sending program changes to the TimeLine (something which I really want to do). Thanks! Dan P.S. I have verified that the program changes get sent to the TimeLine even while there is the buzz.
mike

over 6 years ago

Hey Dan - you definitely have a ground loop going on somewhere. Are the Timeline and the laptop hooked up to the same power source? What is you try running the computer on battery instead of on AC power? If any of your equipment has 3 prong plugs, try using a 3->2 prong adapter to disconnect the ground.
fynn

over 6 years ago

Hey Mike, So I've had time to try a few things... Here are my findings: Setup is as follows: - Guitar -> Timeline -> Computer (audio interface) - Looptimus -> Computer via USB - Looptimus -> Timeline via Midi Power - The Timeline has it's own dedicated power supply (2 prong Australian, straight into wall) - The Looptimus is powered via USB - Plugging or unplugging the computer from power makes no difference. With this setup, there is a very loud hum coming out my computer speakers (monitors connected to my audio interface). The same goes with headphones. If I plug a 9V power adapter into the Looptimus (with midi and usb still connected), the hum is reduced DRASTICALLY, but is still noticeable. If I unplug the Looptimus from USB and power it with a 9V adapter, there is NO hum - but then I obviously can't send midi notes to the computer. Any more help with this would be greatly appreciated. The setup is so simple, I wouldn't have expected any problems like this.
mike

over 6 years ago

Are all of the devices plugged into the same wall plug? If they are on different circuits, it could cause this.
fynn

over 6 years ago

No - nothing else is plugged into the wall. Here is a video of the exact scenario to show you what is happening... https://www.youtube.com/watch?v=dxle7f1xqfY&feature=youtu.be The way I see it - it is either the TimeLine or the Looptimus. Unfortunately I don't have another one of either lying around to narrow it down further.
fynn

over 6 years ago

How can I go about getting more support on this issue? Is this something that other people are able to replicate? Banging my head against a wall here...
mike

over 6 years ago

A random thing to check - Midi cables should have the ground lifted on one side - try flipping the direction of the midi cable opposite to what it is now and see if that works.
tomjackson92

over 6 years ago

Just to add my two cents on this - I ran a midi cable from our keys player who was running click in Ableton to sync the bpm on my Timeline over the weekend. I did two services with that and one without. I had horrendous buzz so I could only use one amp (stereo rig) with the midi cable in. The service without the midi cable I could use both amps without a hitch.
mike

over 6 years ago

Tom - just to clarify, this was simple keyboard to timeline right? No Looptimus?
tomjackson92

over 6 years ago

No Looptimus involved. The midi cable was plugged into his MOTU interface.
fynn

over 6 years ago

I've come up with a couple of suitable work arounds. 1. The issue doesn't occur when I am plugged into my amp instead of the audio interface, and the amp is plugged into a separate wall powerpoint. 2. When I am plugged into my computer via the interface, if I plug a MIDI cable into the MIDI out of the timeline, and into the MIDI in on the interface, the hum disappears (the Looptimus must also be plugged into power for the hum to be completely gone). It seem like this completes the "loop" and removes the grounding issue, since both guitar and midi are plugged into the same interface. 3. I can remove the USB cable all together and send MIDI to my computer via the MIDI cable, and program Ableton to send the appropriate program changes to the Timeline. All in all, these methods should do the job. Ill be purchasing a few more MIDI pedals in the near future, so will test to see if they behave differently to the TimeLine. Thanks for your help. Dan