Induction loop whining

[Owen]

My Church has an induction loop fitted. Some of my basses whine - depending on which angle I am in relation to the loop. I am presuming that I have a tedious shielding-fest ahead of me, or is it grounding or what?

TIA

[Huge Hands]

You may be able to control it a bit by reducing the drive gain of the loop if it has such a control, but obviously you'll need a test person with either a hearing aid or loop tester to make sure you don't turn it down so much that it becomes redundant and doesn't work!

You may be also able to filter the whine out of your signal using EQ, but this could also have a detrimental effect on your "sound". Might be worth it for the peace and quiet!

Nasty problem that affects a lot of church players. I can remember the guiarist in our church band getting a mate to turn the loop off during songs. He often forgot though!

Easiest answer is to get them to fork out for an infra red hearing system

Drastic way is to get them to recable the loop well away from the band area, if there is a dedicated space for the band.

Edited March 21, 2008 by Huge Hands

[BOD2]

Shielding isn't going to cure the problem. You can't shield the pickups and it's the pickups that will be the biggest source of the noise.

Try moving to a different area of the "stage" to see if you can minimise the effect.

It might be possible to use a very narrow band filter to filter out the most annoying frequencies. If the filter is narrow enough this would minimise the effect on your sound, but there will still be an effect on your sound. Some of the Feedback Suppressors have manually adjustable filters that can be set to a particular frequency and can cut that frequency quite tightly. I have to say that I have NEVER tried this with induction loop whine so I have no idea how effective this would be.

You might find [url="http://behringer.com/DSP1124P/index.cfm?lang=ENG"]one of these[/url] fairly cheaply as I think they've been discontinued.

[Owen]

It is not an issue in my nicer/passive basses (Bolin NS5/Jazz) and has not been in other more high end stuff. However in my cheap and cheerful collection that I have "enhanced" using EMG or Duncan pick ups and various pre-amps I get this whining. I can minimise it by angling my body in a certain direction, but ultimately that is not realistic - I just want them to work! The loop is buried in the floor. It would be cheaper for me to go out and buy a US Lakland JO5 - and THAT'S not going to happen (more's the pity).

[phsycoandy]

Owen, i've been there and know where you are coming from with this problem. Other than asking deaf people not to attend, I guess that sort of defeats the object of evangelism!
I solved it by re routing the cable away from the band area, and this has solved the problem, ours was a surface mounted wire so not too much trouble yours sounds a whole lot more complicated.

[Owen]

Discussed this with a fellow bassist in church who has the whole 9 yards shielding done and his bass is now immune to the induction loop. Looks like a trip to the garden centre to buy some slug repellant adhesive copper tape

[Owen]

Just as a sort of update for anyone who might do a search looking for info on this, after a long time of only being able to use one specific bass at Church I realised that the bass channel was being fed into the loop. I took it out this morning and the whining was gone. Why did I not think of that before?

[27 frets]

I've got a problem with my Indie 6 string bass and the induction loop.
It picks up the loop signal (radio mics and lectern mics used for speech only) and then amplifies that through my bass amp causing feedback that way.
I tried changing the soapbar pickups (from Indie own brand to Wilkinson) but that made no difference. The control cavity looks well screened with copper tape (better screening than some of my other basses), so I can't figure out why this bass is particularly suceptible to this when the other basses aren't.
Any ideas?