Active speaker ground loop? Need detective help.

[djk]

It's $27, and will allow you to connect your equipment without a ground loop.

The Edcor is a great budget unit.

If cost is no object buy a Jensen.

http://www.jensen-transformers.com/apps_wp.html

1) Transformers break ground loops. Since the transformer’s primary and
secondary aren’t electrically connected, no ground loop currents can
flow. Hair- pulling, aggravating ground loop related hum and noise
problems disappear.

http://jeffrowlandgroup.com/Technology/LineLevelTrans.htm

[BentMike]

Oh OK, 1:1 transformer. I use them on power with Faraday shield when necessary. Edcor doesn't say what it does.

Hypothesize with me, what about the PC makes this happen where the music player does not cause it?

I'd still expect the common to be common to both channels.

I have a problem where if my USB-USD-DAQ touches my laptop or my fingers or...it stops working until I disable it and enable it. I have the whole mess wrapped in a rubber sheet so I don't trip it out (I move it around a lot). I find the whole mess to be finicky as hell. I have an unfounded impression that PCs are not well suited for music this way. Probably it comes from my being uncontrollably cheap and insist on trying out the lower cost stuff. Someone has to do it.

Thanks,

BM

[djk]

The Y1 capacitors in switchmode supplies are a real problem.

The 1:1 transformer breaks the loop.

(ESP Audio)

[BentMike]

To me that looks like good isolation - how do these become a problem? You are talking to an ME not an EE, so I may be quite dense and uninformed.

I don't get why the Y1's are there though. The few PS I have put together don't have caps like that.

BM

[babadono]

BentMike,

Just FYI. Those caps may not physically be there. It could be parasitic capacitance of the transformer or other parts of the circuit. Much good information about these types of issues can be found at the Jensen Transformer website. Checkout their app. notes and white papers.

babadono

[BentMike]

So then this is how the AC gets coupled to the DC... I would worry about this in laying out conductors for data (also inductive coupling) acquisition, but I haven't got much understanding of audio.

BM

[babadono]

BentMike,

So when you are using the battery powered player there is no AC to get coupled/induced/ground looped into the powered speakers. When you are using the player is it with the same cable? From your earlier posts I think it is a different cable. Turn off the speakers. Take the cable that you are using with the computer and unplug it from the computer. Leave the speaker end hooked up. With the speakers off, short what you think is the ground contact to the two signal contacts on the plug that normally goes into the computer. Turn the speakers on. Is there no hum when you do this? If there is no hum when you do this but as soon as you plug it into the computer you get hum you will need one of those gizmos that DJK suggested. Sometimes that is the only thing that will fix this.

babadono

[BentMike]

I really want to thank you guys. The results are actually fantastic.

I tried the shorting the jacks business and had to put the lifted ground back in place, still not right, but one jack was worse and it traveled when I switched speakers.

You kept asking me about the cables, so I decided to pay really close attention to them (I was being casual). I found the best coax in my closet - I have bunch of odd stuff I pick up at university surplus, and redid them using this. I check resistance as went along to make sure the jacks weren't breaking down or something, no problems. I will never be so casual about cable making again.

I am so glad - these things sound great. They are the best sounding small speakers I have ever heard. 50W high, 50W low, times two. No amps and pre's to mess with - so simple. I like a lot of music and so far they cover it all from bass heavy, weird electric sounds techno, to Russian men's choir in a cathedral, nasty shredding, and sweet Wailin' Jennys. It is all good, and very powerful.

They are meant to be placed about a meter away, but they are wasted if that is all you do with them. I am amazed. There is something to this cabinetry, the baffle is 40mm thick, the rest 19mm. Very dense.

I may have to try some Klipsch-ish stuff, or build some horns...seems like you smart guys know what you are talking about.

'nuf said,

Thanks so much for the help.

BentMike

[leftwinger57]

That mini jack into the RCA ends is how I get my computer tunes . Out of the headphone port into a y splitter into the RACs and run them from one room to another and it terminates at audio 1 of the rear of my Yamaha RX-V665. It does sound a bit convaluted but it does work and I get I-tunes, I-net radio and even run a jumper from the Yammy into my Onkyo P-301 pre and it works for my 2-chll rig as well.

[CECAA850]

I moves to the other speaker if I switch the cord.

If your sound issue moves from speaker to speaker when you switch cables, that indicates a cable issue (unless I'm misreading). That's why I suggested the above solution. They're very cheap.

[]

Glad you got it up and running!