Speaker w/ a common ground?

**KyleYankan** · 04-11-2005, 11:38 AM

Hi everyone. I'masking if I can hook all my speakers up to a common ground. I didn't think it could be a problem, but I'm not too good with AC waveforms. did anyone do this? Any loss of sound quality? I plan on mixing my amp signal and my HU signals so my carputer can operate seperate of the HU and vice versa.

PS: sorry if this is a double post - I just tried once and it didn't go.

**Confused** · 04-11-2005, 11:50 AM

Well, putting two inputs onto 1 speaker *might* not cause a problem, providing you take both the +ve and -ve signals from the speakers back to each respective source, otherwise you'll probably find you'll have no sound!

As for whether you can hook up speakers to both amp and HU, that's for someone else to tell you, as I don't know!

Garry

**KyleYankan** · 04-11-2005, 03:23 PM

There's a quick cirucit you can use called a mixer - that allows for two inputs into one output. Not a Y-adapter, but a mixer. I know it's possible - this is more a time saving measure.

**gu_gEEk** · 04-11-2005, 03:41 PM

Originally Posted by KyleYankan

There's a quick cirucit you can use called a mixer - that allows for two inputs into one output. Not a Y-adapter, but a mixer. I know it's possible - this is more a time saving measure.

Using a mixer should take care of any fields (which would cause noise) created by grounds from other devices as long as everything is grounded well and the mixer is installed away from the speakers.

**KyleYankan** · 04-11-2005, 04:41 PM

Also for anyone who wants the circuit or wants to know more about this SIMPLE mixer::

http://www.tkk.fi/Misc/Electronics/c...s/linesum.html

**KyleYankan** · 04-11-2005, 10:26 PM

AH!

My stupid = that mixer circuit is for LINE LEVEL inputs, not SPEAKER LEVEL. So 3 questions:

Would it be ok to hook two outputs (SPEAKER LEVEL) to one speaker, no circuitry?
Would I have to drop the HU's SPEAKER OUT to LINE OUT levels and then run it though that mixer?
What happens if I hook my Speakers to the low nmpedance hookup and my carputer to the high impedance of my amp?

**dave2** · 04-12-2005, 04:13 AM

Woah, why??? Since you aren't planning on having the carputer and head unit both putitng out sound at the same time, why would you do something like that?? You are gonna end up sending current back to the other unit and possibly damaging it. Please, find either an AUX input adapter for your HU, or get a preamp unit with multiple inputs. You could even just build a little relay board which would switch between the sources..

Dave

**KyleYankan** · 04-12-2005, 10:02 AM

Originally Posted by dave2

Woah, why??? Since you aren't planning on having the carputer and head unit both putitng out sound at the same time, why would you do something like that?? You are gonna end up sending current back to the other unit and possibly damaging it. Please, find either an AUX input adapter for your HU, or get a preamp unit with multiple inputs. You could even just build a little relay board which would switch between the sources..

Dave

I just wanted to have a easy to use switched. I wouldn't run both. I'm considering the relay now. Only need 4 low wattage relays, so It can't be too hard. OR hey, tow DPST! I have those. tikme to get soddering.