Would Optical Lead Elimate buzz/hiss?

[goof]

Ok, I know this is an unpopular topic but....

The 'ol digitheatre buzz 'n hiss is really starting to bug me. The sub hums when on but that's not really the problem...it's the buzz that comes from the speakers.
I noticed the other night when I had the amp/sub & decoder on if I removed the co-ax cable that links the player and decoder his noise was almost eliminated. I may be over simplifying but would an optical lead reduce or eliminate this? Anyone know if Argos stock them and if it is still possible to test that sort of equipment then return it if not satisfied?

Thanks for any input.

[Neon]

An interesting question this! I noticed a similar problem with my setup (SD100E and RXV-620RDS) - and only when the coax was being used. I thought something had become loose and I was ferreting round the back and discovered that moving the coax round altered the volume of the buzz. Moving the stand 1" further out from the wall has considerably lowerd the level!

I've come to the conclusion that as everything these days is unearthed, even the shielding on coax is able to pass on any mains hum it picks up. The answer is probably to earth the whole setup at one point (to prevent earth loops). Alternatively, you could try optical (which I had also decided would work). If you do try it, I'd be interested in your findings.

[goof]

I'd heard a lot of ppl mention the ground loop but I was wondering how I would eliminate it? I checked out the plug on the digitheatre's sub and it only has a neutral & live - the decoder runs off a transformer. So how would I earth it all at one point?

I'd try out optical if anyone could confirm if there's somewhere that stocks them (cheaply too!) that would allow me to test it and take it back.

[DunkWho]

2 comments ...

1 - I'm guessing that the decoder in the digitheatre only decodes when fed an input - or to put it another way ... it only gives a decoded output when an input is connected. You may well be hearing amplified "silence" when the coax is connected which sounds like a hiss, and a muted output (ie not amplified) when the coax is removed which doesnt give any output because the amplifer stage has been muted by the decoder stage because the decoder has realised that theres nothing to decoder ... (that doesnt ready very clearly but i hope you'll get my drift).

2 - An optical lead will remove the possiblity of any ground looping between a dvd player and decoder, no conductive material so the 2 units should be issolated, maybe argos would be a good place to start - buy it, try it, take it back it if doesnt help, take it back if it does work but its too expensive - then buy a more reasonably priced lead :D

Dunkwho

[jonpeat]

OK..I had the same problem and it drove me nuts. Anyway, if you are using a coax then put a piece of wire around the coax point on your DVD player and put the other end on a radiator or something else metal.
However, an optical lead will get rid of it totally (as will the above method but it is a little more fiddly).

I hope that you soon have interferance free viewing.

[goof]

Dunkwho, I thought that would be the case and that was what I was referring to when I mentioned "over simplifying". I just couldn't be arsed putting it into such eloquent wording :D
Will check out optical situation.

Jon, I'd tried the radiator method before to no avail...think I maybe didn't do it right tho so will try again.

[kcxdev]

Originally posted by goof
I'd try out optical if anyone could confirm if there's somewhere that stocks them (cheaply too!) that would allow me to test it and take it back.


Argos (http://www.argos.co.uk/webapp/commerce/command/ExecMacro/ols_prod_detl.d2w/report?prrfnbr=3648658&prmenbr=6970&type=big&thisMode=ols&cgrfnbr=45648) have one for the PS2, but they're all the same anyway.

[jonpeat]

Took me a couple of goes for the radiator method but got there in the end. :D

[sonnyJIM]

On a similar topic, is there such a thing as a "good" optical cable or are they all the same in terms of sound quality.