robs

Got the Infinity 605cs (see -'can't believe they're so hard to get' thread). Put them in last night. Very happy - the quality of sound is waaay better - more clarity, much better imaging and much more 'oomph'. BUT.. have developed a buzz - interference (buzz frequency varies with revs, and volume of buzz seems to vary for no reason at all. Cannot hear it above very low listening volumes - or quiet bits of music, but it is annoying between tracks). Have fitted the crossovers in the doors (just in front of the main speakers (MY95), and apart from that, nothing has changed (using a sony CD and a Philips amp, but they were connected up to the original speakers before).
Anyone got any ideas as to why (coils in the crossovers?), and more importantly, how I can get rid of it. Any advice gratefully received..

gareth60

Sounds like you need a suppressor. The buzz will probably be coming from your alternator (indirectly). Is the buzz coming from just one set of speakers or both??

You could try a suppressor on the power input of your headunit and maybe one on the power input of your amp.

Ta
Gareth

robs

Hi Gareth60 - have you fitted yours yet? BIG improvement!!? The buzz is from both speakers. Strange thing is that I did not notice it with the old original speakers...either they were even crappier than I thought (and were not transmitting it), or it has only developed with fitting the new speakers..
Are suppressors the type of thing you buy standard off the shelf, or do they vary? Don't know much about them..

gareth60

Yup, changed the front and backs today, very impressed. The originals were really very cr@p, more than my wifes Corolla standard fit items.

You should be able to buy a suppressor from Halfords or any car hifi shop, also Maplins will do them.

It'd not a garentee that it will fix it, but I hope it will.

I live in mid kent and I think I may have one lying around, i'll take a look and if your passing your welcome to it.

audio g man

You need to find whats causing the noise by eliminating items one by one.

I've never comes across passive filters introducing noice into a system. Does the noise come through all speakers? Are all your speakers powered by external amplification? Have you run all new speaker cables in? What sort of amp(s) are you using?

robs

Gareth - thanks for the offer...don't often get over that way (though did do the Toyota track day at Brands a few weeks ago), but ta anyway. I'll have a look in Halfords.
Audio G man - the noise is through the fronts - seems to be the tweeters only. Cannot hear it on the rears. Only the fronts are powered by the amp (Philips DAP600) - the rears are direct off the head unit (Sony CD/tuner). Can still hear buzz through the front tweeters when the head unit fader is full to the front speakers (and both the rear speakers and the line out (to the amp) are on the 'rear' of the fader), so I suspect the problem is with the amp?. I'll get a suppressor & have a play.

chiark

Riiight, sounds like a ground loop potentially.

Unplug the RCAs to the amp. Noise still there?

Start systematically finding where the noise is coming from, then try to fix it

Incidentally, I had ECU noise induced in a passive x-over when I put it in the driver's kick panel. Never heard of the problem before or since, but it's possible...

gareth60

Hmm, yes, heard of this before.

Can this be caused when the amp and headunit are earthed at different point on the car??

robs

OK, unplugged the phonos = noise gone. So we are talking either the phono lead or the head unit? I will be going to Halfords.. Ta for the help.
Oh, I found an alternative solution......turn it up LOUD!! That gets rid of it..!