A note on the Behringer. Yes, it has 12 filters, but I have 7 of them shut off. The other 5 I have on are set on a very specific setting. 4 of my settings are one for each string, the 5th is for finger noise. It took time to get that set up, but for me, it has worked at stopping feedback thru an upright bass in a loud situation, and I've been happy with the tone.
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Double Bass Feedback Eliminator?
- Thread starter glenfong
- Start date
A note on the Behringer. Yes, it has 12 filters, but I have 7 of them shut off. The other 5 I have on are set on a very specific setting. 4 of my settings are one for each string, the 5th is for finger noise. It took time to get that set up, but for me, it has worked at stopping feedback thru an upright bass in a loud situation, and I've been happy with the tone.
Wouldn't it be nice to have a little magic microphone box that incorporated a notch/hi-pass, phase switch with an isolation transformer, and a Combo Jack Input. Those of us who use EA,GK, and WW could really use such a device. There are many little boxes out there but they don't have all these features. A balanced line out with a ground lift would be needed and a 1/4" line out to send the signal to the amp of your choice.
Ric
Ric
+1 on taking the time to set these up right. They auto feedback part is basic notch but the programmable parametrics are incredibly versatile. It's amazing how loud you can get still sounding natural and without feedback. Also none of the funny put the amp in a certain place and stand in another. Or a dash up to the stand when you forgot to turn off the amp between sets.
Now these I'd like to see built into combos.
A couple of other things to look at:
- The velcro on your afterlength may or may not be helping much. How wide is it, how tight is it around the strings, and how soft is the material? If you want to kill most of the afterlength sound wind something soft through the strings and tie it tightly; closer to the bridge mutes more, further mutes less. I'm just now starting to move away from afterlength muting, but still have a thin leather strap woven between the strings. I can adjust the amount of muting by moving it up toward the bridge or back closer to the tailpiece as the situation demands. Up against the tailpiece, it's basically not doing anything. The easiest way to check is to play in the situation that causes feedback and then have a friend firmly grasp the afterlength by the bridge and see if the feedback is affected.
- Your pickup shouldn't be the problem. In my experience, the Full Circle is one of the most feedback resistant pickups out there.
- Make sure you aren't in the direct line of fire of your speakers. If the speakers are aimed at your bass, it's more likely to feed back.
- Last, how's your pizz technique? Part of playing amplified is developing "self muting" right and left hand techniques that kill the vibrations of all but the strings you're playing on. The right hand can be trained to automatically deaden all the strings lower than the one you're playing, while the left can mute all of the strings higher than the one you're playing. For me, this was one of the biggest (if not the biggest) pieces of the feedback puzzle.
- The velcro on your afterlength may or may not be helping much. How wide is it, how tight is it around the strings, and how soft is the material? If you want to kill most of the afterlength sound wind something soft through the strings and tie it tightly; closer to the bridge mutes more, further mutes less. I'm just now starting to move away from afterlength muting, but still have a thin leather strap woven between the strings. I can adjust the amount of muting by moving it up toward the bridge or back closer to the tailpiece as the situation demands. Up against the tailpiece, it's basically not doing anything. The easiest way to check is to play in the situation that causes feedback and then have a friend firmly grasp the afterlength by the bridge and see if the feedback is affected.
- Your pickup shouldn't be the problem. In my experience, the Full Circle is one of the most feedback resistant pickups out there.
- Make sure you aren't in the direct line of fire of your speakers. If the speakers are aimed at your bass, it's more likely to feed back.
- Last, how's your pizz technique? Part of playing amplified is developing "self muting" right and left hand techniques that kill the vibrations of all but the strings you're playing on. The right hand can be trained to automatically deaden all the strings lower than the one you're playing, while the left can mute all of the strings higher than the one you're playing. For me, this was one of the biggest (if not the biggest) pieces of the feedback puzzle.
Hi Chris,
The velcro is 3/4" wide, it's used for keeping cables tidy. Will get someone to grab the strings as a test too.
I'm standing off to the side of the speaker, but again someone also mentioned the M-Line 12" also throws some sound through the vent slots on both sides (part of the transmission line design), of course the main sound is directly in front.
I used only the Underwood since I'm still new to the Full Circle. This week the Full Circle will give it a go since I've dialed in some new tone settings on the amplifier.
Points taken on right/left hand muting technique. Will make a more conscious effort on that (always learning!).
Appreciate your comments along with everyone else.
Sincerely, Glen
Happy to report this anti-feedback device works. I picked up a used one and messed about with it for weeks with little results. After reading the manual very carefully, when it's set up properly it does cut down on the feedback with very minimal change in tone (at least to my ear).
I run my pickup (either an Underwood or Fishman Full Circle) into the SL-820 and perform recommended setup, afterwhich I run the output of the SL-820 to the HPF (Fdeck's design) then to the amplifier. It can also be used with your amp's effects loop if it's the serial type.
Probably not for everyone, but it works for me when the band is real loud. Running a direct line to the p.a. at a low volume just for presence helps out a lot as well.
Many thanks for all of your replies, Glen
I run my pickup (either an Underwood or Fishman Full Circle) into the SL-820 and perform recommended setup, afterwhich I run the output of the SL-820 to the HPF (Fdeck's design) then to the amplifier. It can also be used with your amp's effects loop if it's the serial type.
Probably not for everyone, but it works for me when the band is real loud. Running a direct line to the p.a. at a low volume just for presence helps out a lot as well.
Many thanks for all of your replies, Glen
I have used the 1st unit you have pictured. It mainly gets used for PA at our church. I was not too pleased with it because it only has 12 notches (auto) and another few for manual preset. I felt I had more control over the PA with just a 31 band EQ. My BIGGEST gripe with it is that it will not detect subtle feedback (like the "trail" after a word is spoken) instead ours seems to need to "cook" on it for a while. Seems to take about 3 seconds of good loud feedback before it clamps it.
I ended up bypassing the unit and just using a 31 band eq in the end as I filled up all the filters and still could not get loud enough! (We have 6 open lapel mics- not an easy job for any unit) But I do see it as a nice suppliment to a 31 band EQ when you hit the bottom and are still feeding back.
I ended up bypassing the unit and just using a 31 band eq in the end as I filled up all the filters and still could not get loud enough! (We have 6 open lapel mics- not an easy job for any unit) But I do see it as a nice suppliment to a 31 band EQ when you hit the bottom and are still feeding back.
I agree--I am playing in a very loud rock band, and the dsp1124 made notching out the trouble frequencies a piece of cake. It is easy to over-do it though, I found I only need 3-4 filters to get the FB totally gone, without sacrificing a good tone.
I have a carved bass, so it is particularly susceptible to feedback. The instrument is resonant at about 100hz and 80hz--there have been times when it starts to howl, and I looked down and saw the top of my bass moving almost a full inch! Probably not good for soundpost placement, seam damage, and really not good for speakers.
I have to second the piece of foam wedged behind the tailpiece, it works.
I play Rockabilly loud using my Underwood, Pro Platinum (love it) , 350 watt head thru 4 tens and have very little problem with feedback. A good EQ is critical also.
I play Rockabilly loud using my Underwood, Pro Platinum (love it) , 350 watt head thru 4 tens and have very little problem with feedback. A good EQ is critical also.
I'd use physical/acoustic solutions before resorting to electronics. First off, make sure the amp isn't pointing at your bass. If possible have the bass side-on. The tips about damping the after-length and the tailpiece are helpful.
Next, decouple the amp from the floor. You can buy Auralex 'Gramma' damping boards commercially, but I find a sheet of foam or a couple of pieces of 'pool noodle' foam sliced down the middle work well under the speaker box. Also add a bit of damping material under your end pin.
BB King used to cure feedback in his guitar by filling it with sox, but I guess you'd empty your sock drawer before you filled a bass...
Next, decouple the amp from the floor. You can buy Auralex 'Gramma' damping boards commercially, but I find a sheet of foam or a couple of pieces of 'pool noodle' foam sliced down the middle work well under the speaker box. Also add a bit of damping material under your end pin.
BB King used to cure feedback in his guitar by filling it with sox, but I guess you'd empty your sock drawer before you filled a bass...
