Feedback Destroyer

[mr zed]

Just wondering if any of you guys have used a feedback destroyer with the DB? I need to play at a fairly loud volume and feedback is a real issue. I have some f-hole blockers on the way which should help (possibly solve the problem) but just thinking that a FBD may also be a belt and braces solution. I have successfully used FBD's in FOH & monitoring situations in the past with PA and wondered if there is any reason why this wouldn't work in the DB signal chain?

Edited March 15, 2018 by mr zed

[Happy Jack]

Bizarrely, I have never actually used either of my two FBD units when playing DB, perhaps because I don't tend to play DB in very loud situations.

My experience with f-hole blockers hasn't been great, TBH.

[TPJ]

Loud and double bass don't usually mix unless you are running steel strings and a mag pickup. 

Are you using an amp onstage and if so, how close are you standing to it? 

You could try something like the FDeck preamp that has hpf to dial out lows and a phase switch.

[TheRev]

I've only tried a feedback destroyer one with double bass and to be honest, I wasn't expecting much so I may have been a bit biased in my 'tried it, didn't like it' response.

I'd used feedback destroyers previously in the PA/FOH of band I was in that played a lot of small pubs. While it was certainly very effective in removing troublesome frequencies, these frequencies were often the ones that were quite important to vocals, so it just ended up pulling out all of the nice sounding frequencies, leaving a hollow, thin vocal sound.

When I tried it with double bass, the same thing happened - problem frequencies were pulled out but the resulting sound was thin and weedy and effectively useless. it put me in bad mood for the whole gig, but as I said, this was exactly what I was expecting would happen.

I've had better success with a preamp with a high pass filter, phase switch and a variable notch filter, though the notch filter still removes some of the frequencies that I wanted to hear so I don't use it unless I absolutely have to.   My current setup, which is very feedback resistant is a magnetic pickup, F-hole mutes, preamp with a phase switch and the HPF set to around 80hz, no bass in the monitors and my backline up on a stand at about chest height.  if I'm still having issues with feedback I throw stuff at the guitarist until he turns his amp down. 

 

Dave

Edited March 16, 2018 by TheRev

[mr zed]

Thanks for the replies. I've just bought a FBD off ebay (which I can use on my PA monitors). When it arrives, i'll give it a go with the DB & report back. I'm thinking the signal path will be DB into Bassbone into FBD, into amp. As The Rev points out, I think it will work from a feedback suppression point of view but may remove some important frequencies that will render it useless.

Should have bought a Tonebone Pz Pre for the notch filter & phase switch rather than the Bassbone. Doh!

[TheRev]

I've found the most effective anti feedback tools are the high pass filter, phase invert switch and mutes/dampening, in that order.

If you don't have those, then staying away from feedback inducing situations  by careful amp placement (raised as high as possible, ideally shoulder height so it's well away from the body of your bass) and your position on stage (away from monitors and presenting as low a profile as possible to any sound sources) are the only things you can do to help.

[mr zed]

Thanks Dave. The HPF on the Bassbone has no effect when engaged so the feedback frequencies must be above 175hz. The HPF on my amp must be set higher as that helps a bit (but I then lose some bottom end). Amp is a Genz Benz STL9.0 into a Bergantino HD210. Not tried raising it off the floor yet. Having said that, I ran a line out of the Bassbone into the desk and isolated the amp (so just going through FOH). Same feedback issues. I'm using a J-Tone piezo pickup and the strings are Innovation Golden Slaps. Band is a 6 piece with guitar, drums ( kickdrum registers a signal on my amp when kicked), keys, sax and vocals. It was never going to be quiet!