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Take 5 humming [SOLVED]

Take 5 humming [SOLVED]
« on: October 11, 2021, 02:59:20 AM »
This is what I wrote Sequential support. Does/Did anyone have/had problems with Take 5 humming? If so, what was the cause and how did you solve it?

"I got my Take 5 two days ago, and while I really love the sound and playability so far, I have a problem with a noticeably loud hum.

All my other synths (among them the OB-6 and the Prophet 6 as desktop versions) are connected via balanced cables for audio into a Presonus StudioLive Series III 32R and USB for MIDI, which works flawlessly without any excessive noise or hum.

When I connected the Take 5 for the first time with balanced cables, I noticed a distinct hum. Strangely, when I disconnected the USB cable, the hum got *louder*, so I tried unbalanced cables, which alleviated the problem. The hum was still there, but not as loud.

The problem is that the hum gets louder when I switch on other synths.

I have tried several different balanced and unbalanced cables, and another power outlet, but the hum stays the same (and independent from the main volume).

Via headphone on the Take 5, there is *no* hum!

It is important for me to know if this could be due to a faulty device, in which case I would send it back and replace it.

If not, I would be very grateful for any problem solutions."
« Last Edit: October 11, 2021, 10:12:51 AM by extempo »

Re: Take 5 humming
« Reply #1 on: October 11, 2021, 08:02:34 AM »
I would get rid of usb midi and do din midi which is galvanic isolated. Din midi is a current loop through a optical feature, optocoupler, and you have isolation you need.

That is what I suspect anyway.

When coming to ground loops it's always weird. USB is crap regarding this. Possibly special cables could remedy that separating shield and ground and things like that. And I usually start having issues with usb cables, not for midi at all, other things, and cables longer than 1.5m. Din midi stuff I have several 10 meter cables and no problems.

Re: Take 5 humming
« Reply #2 on: October 11, 2021, 08:59:17 AM »
I would get rid of usb midi and do din midi which is galvanic isolated. Din midi is a current loop through a optical feature, optocoupler, and you have isolation you need.

That is what I suspect anyway.

USB has nothing to do with it; the hum stays the same, whether it is connected or not.

But it seems I have already found the solution: Today I tried plugging the Take 5 into the same multi socket as the Presonus, et voilą, the hum was completely gone, even when switching on everything else. I now have ordered a longer power cable which will hopefully sort things out once and for all.

Strange, though, that my other synths (including two Sequential ones) don't have these problems (and can be used with balanced audio cables) ...

Re: Take 5 humming
« Reply #3 on: October 11, 2021, 09:46:25 AM »
You found one ground loop, good.
Two different outlets not on the same fuse, will have ground going all the way to fuse box and then over to the other side. In fuse box all ground are connected.

So you had a long ground loop over power, then shorter ones through signal ground and the rest. And that usb made a difference even to the worse disconnecting tells it is involved too.

Ground loops is a bitch.....not always obvious or logical what fails....