Hummm... [resolved]

oldvstar · 1040

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Offline oldvstar

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on: September 18, 2024, 10:21:35 AM
I recently retrieved my Crack from my son, bought some HD6xx headphones and using an old cell phone for streaming from Tidal I have been settling in to listen to music through the Crack again. The old phone was a temporary solution just so I could start listening to music while I waited for a Wiim pro plus to arrive. I now have the pro plus and my first listening session with it was both positive and negative. The positive is that I'm hearing much improved sound quality, this justifying the purchase. The negative is that I now hearing a nice 60hz hum through the headphones. The pro plus is powered by 5vdc through an USB C cable connected to an included wall wart. I'm wondering if putting an opto-isolator inline with the USB C cable will solve this, it maybe someone here has dealt with this and has a simple solution.
« Last Edit: September 26, 2024, 01:55:02 PM by Paul Birkeland »

Terry

Crack/Speedball, Beyerdynamic DT990 Pro 250, Sennheiser HD6xx, Wiim pro plus


Offline Paul Birkeland

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Reply #1 on: September 18, 2024, 11:04:02 AM

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline oldvstar

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Reply #2 on: September 18, 2024, 12:10:51 PM
Thanks Paul, for 0.63 cents plus shipping this is a cheap and easy thing to try.

Terry

Crack/Speedball, Beyerdynamic DT990 Pro 250, Sennheiser HD6xx, Wiim pro plus


Offline Paul Birkeland

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Reply #3 on: September 18, 2024, 03:53:48 PM
While you're waiting, also be sure that the power transformer screws are tight, and let us know if you happen to have painted the bottom side of the top plate.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline oldvstar

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Reply #4 on: September 26, 2024, 10:14:16 AM
Thanks Paul, the diodes did the trick, no more hum. Also, transformer screws are tight, and no, I did not paint the underside of the transformer top plate.

Terry

Crack/Speedball, Beyerdynamic DT990 Pro 250, Sennheiser HD6xx, Wiim pro plus