Forums - Print Page

Forums
https://www.decware.com/cgi-bin/yabb22/YaBB.pl
EQUIPMENT FORUMS >> SE84UFO2 >> Speaker Ground Help
https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1679686986

Message started by Nrobhenry on 03/24/23 at 20:43:06

Title: Speaker Ground Help
Post by Nrobhenry on 03/24/23 at 20:43:06

Apologies if this is a major dummy issue, but my speakers (Klipsch Heresy III) are putting out a low level buzz when connected to my UFO2, even when the UFO2 is not connected to power or any other sources. Playing around a bit, I've found that if I have a connection between the speaker terminals or speaker wire and the input jack, such as my finger or a piece of wire, the buzz goes away... I'm assuming this is because I'm eliminating the ground loop. I can't figure out why the connection from the UFO2 to my speakers is creating a buzz unless grounded to the input jack. I subbed in my 2011 SE84C+/CKC and didn't have this issue. Any idea what would be causing the buzz on my UFO2?

Thanks so much for your help!

Title: Re: Speaker Ground Help
Post by milkplus on 05/13/24 at 11:55:33

Hey there. Did you ever get this fixed? I'm having a similar issue after introducing a subwoofer into my system. Loud buzzing even when everything is switched off...

Title: Re: Speaker Ground Help
Post by Nrobhenry on 05/13/24 at 17:52:30

Nope, my fix was to place a bit of speaker wire. Will try to remember to send a photo when I get home this evening.

Title: Re: Speaker Ground Help
Post by milkplus on 05/13/24 at 18:41:40

Thank you. I'd appreciate it.

Title: Re: Speaker Ground Help
Post by Nrobhenry on 05/15/24 at 18:39:53

Here you go. Not elegant, but it works. If there's someone smarter than me that understands the wiring going on below that could throw out a theory of why this solves for the hum, I'd love to hear it.

Title: Re: Speaker Ground Help
Post by Donnie on 05/15/24 at 19:36:53

It has something to do with magnetic fields.
Or ohms, or capacitance, or micro-farads .
One of those electrical terms
I'm just a machinist. Electricity is a magic thing to me, kinda like how does gravity work.

Title: Re: Speaker Ground Help
Post by LiquidBlue on 05/15/24 at 20:51:14

Interestingly gravity and ground have a really strong affinity to each other.

Title: Re: Speaker Ground Help
Post by Nrobhenry on 05/15/24 at 22:29:04

For the record I understand grounding. I’ve just never encountered another instance of a speaker posts not being grounded along with the rest of the amp.

Title: Re: Speaker Ground Help
Post by CAJames on 05/15/24 at 22:35:49

Quote:

Interestingly gravity and ground have a really strong affinity to each other.

Yep. :)

But seriously, Donnie is right…maybe. The OP doesn’t have a ground loop if there is buzz with no source or power cords, i.e. only speaker cables attached to the amp, because there is no connection to ground. To me it sounds like the speaker cables are acting like an antenna and picking up some kind of EM noise. How long are the cables? And if you move them around does the noise change at all?

Title: Re: Speaker Ground Help
Post by CAJames on 05/15/24 at 22:55:30

Quote:

….I’ve just never encountered another instance of a speaker posts not being grounded along with the rest of the amp.

I can’t find a reference ATM, but this is in fact a feature of the UFO amps. The “floating ground” allows bridging into mono without any loss of sound quality.

The other thing, that I didn’t notice the first time I looked at your picture, is it looks like you’re connecting the red/hot speaker wire to the RCA jack, not the black/ground one. That makes me think it is even more likely you are picking up noise.

Title: Re: Speaker Ground Help
Post by Nrobhenry on 05/16/24 at 22:21:32

Thanks, I had totally forgotten about that. I can’t recall whether I had disconnected my powered sub when I was experiencing the issue, but that could explain it for the other user running into similar issues.