Acoustic feedback

[Cornfedapache]

What's a good hint (aside from playing behind the amp!!!) for avoiding feedback on an acoustic bass?

Are there any 'plug-ins' that you can get to limit teh signal at all without diminishing sound quality?

Ta!

[High score]

[quote name='Cornfedapache' post='484245' date='May 10 2009, 12:03 PM']What's a good hint (aside from playing behind the amp!!!) for avoiding feedback on an acoustic bass?

Are there any 'plug-ins' that you can get to limit teh signal at all without diminishing sound quality?

Ta![/quote]


Yep, loads of methods eg if you have an internal boom mic or piezzo you can blank over the sound hole. If this is not suitable then you can use electronic means but these are commonly attached to the sound desk eg Graphic Equaliser.

I have used these (see below) specifically for acoustic, drum overheads and monitors ie gear that normally contributes to feedback. It can be set up to hunt automatically and will reset itself. It has ultra narrow notch so you won't hear the filters working and is pretty idiot proof. It can be set up at the acoustic insert on your desk channel, set up and left alone.



[url="http://www.soundslive.co.uk/product.asp?id=3991"]http://www.soundslive.co.uk/product.asp?id=3991[/url]

I have a signiifcant amount of pa gear to clear and sold two already to a BCr. I can sell you my last one for £50 +pp. Normally £130.

Iain

(ps:check my feedback threads - all gear is very, very good)

[OldGit]

[quote name='High score' post='484256' date='May 10 2009, 12:17 PM']Yep, loads of methods eg if you have an internal boom mic or piezzo you can blank over the sound hole. If this is not suitable then you can use electronic means but these are commonly attached to the sound desk eg Graphic Equaliser.

I have used these (see below) specifically for acoustic, drum overheads and monitors ie gear that normally contributes to feedback. It can be set up to hunt automatically and will reset itself. It has ultra narrow notch so you won't hear the filters working and is pretty idiot proof. It can be set up at the acoustic insert on your desk channel, set up and left alone.



[url="http://www.soundslive.co.uk/product.asp?id=3991"]http://www.soundslive.co.uk/product.asp?id=3991[/url]

I have a signiifcant amount of pa gear to clear and sold two already to a BCr. I can sell you my last one for £50 +pp. Normally £130.

Iain

(ps:check my feedback threads - all gear is very, very good)[/quote]

Iain is, indeed, a top bloke.

Other ideas:

My acoustic bass (Crafter BA400) had a phase switch button that used to cancel feedback, or to be precise it moved it from one note to another. It nearly always worked. I guess you could switch pre-amps to one that has that feature.
Otherwise, how about the Behringer Shark?
[url="http://www.soundslive.co.uk/product~name~Behringer-DSP110-Shark~ID~1639.asp"]http://www.soundslive.co.uk/product~name~B...ark~ID~1639.asp[/url]


Iain is a top bloke, by the way

[High score]

Shucks Si, you're making me blush..............but thanks for the support...........how is the sax by the way??


Yep, Si is right, I forgot about the notch filter that may be on your acoustic however while they are effective, it will not accommodate you moving about on stage very well and will require a reset every time you encounter a different Hz band. If you have onboard electronics, just patch over the sound hole. Cheaper and works a treat.

[OldGit]

[quote name='High score' post='485151' date='May 11 2009, 04:11 PM']Shucks Si, you're making me blush..............but thanks for the support...........how is the sax by the way??


Yep, Si is right, I forgot about the notch filter that may be on your acoustic however while they are effective, it will not accommodate you moving about on stage very well and will require a reset every time you encounter a different Hz band. If you have onboard electronics, just patch over the sound hole. Cheaper and works a treat.[/quote]


Sax is fine, ta .. Not had a gig to play yet but it's fine at home

Round hole plugs are relatively easy to get
[url="http://www.gjsguitars.com/index.jsp?searchStr=AA0616+"]http://www.gjsguitars.com/index.jsp?searchStr=AA0616+[/url]

[High score]

[quote name='OldGit' post='485155' date='May 11 2009, 04:15 PM']Sax is fine, ta .. Not had a gig to play yet but it's fine at home

Round hole plugs are relatively easy to get
[url="http://www.gjsguitars.com/index.jsp?searchStr=AA0616+"]http://www.gjsguitars.com/index.jsp?searchStr=AA0616+[/url][/quote]


Pleased the instrument of brass coloured metal is well.............boy did I make a mistake and get an ear bashing when I described it as brass before...............

yep, unless you get something like a Washburn which can have a bloody oval one...............old cds and gaffer tape anyone??

[Cornfedapache]

[quote name='OldGit' post='485155' date='May 11 2009, 04:15 PM']Sax is fine, ta .. Not had a gig to play yet but it's fine at home

Round hole plugs are relatively easy to get
[url="http://www.gjsguitars.com/index.jsp?searchStr=AA0616+"]http://www.gjsguitars.com/index.jsp?searchStr=AA0616+[/url][/quote]

So, without sounding truly dense...

How does the vibration from the strings get into the body then?

[OldGit]

[quote name='High score' post='485164' date='May 11 2009, 04:29 PM']Pleased the instrument of brass coloured metal is well.............boy did I make a mistake and get an ear bashing when I described it as brass before...............

yep, unless you get something like a Washburn which can have a bloody oval one...............old cds and gaffer tape anyone?? [/quote]


ha ha My aim is to educate
The BA400 has an odd shaped sound hole too

[Paul Cooke]

I run my acoustic bass through a Zoom A2.1U and use the feedback killer function. When I get feedback, I just engage the killer and it automatically finds the offending frequency and notches it out. The Zoom also has some nice effects which I find useful when mixed in in moderation.

[Paul Cooke]

[quote name='Cornfedapache' post='485223' date='May 11 2009, 05:53 PM']So, without sounding truly dense...

How does the vibration from the strings get into the body then?[/quote]

the strings are anchored at the bridge, the bridge is attached to the soundboard (upper face). The vibration of the strings is therefore transferred through the bridge to the soundboard which is where most of the sound comes from. The soundhole is so the vibrating air inside the body can help transfer energy to the outside.

When you're using a pickup, the amplified sound gets into the bass via the soundhole and causes the soundboard to vibrate and this is picked up by the pickup and subsequently fed back round the amplification loop. A soundhole cover cuts down on the sound getting back into the bass. It also makes the bass acoustically quieter, but your using the pickup anyway.

[Cornfedapache]

[quote name='Paul Cooke' post='485556' date='May 12 2009, 07:55 AM']the strings are anchored at the bridge, the bridge is attached to the soundboard (upper face). The vibration of the strings is therefore transferred through the bridge to the soundboard which is where most of the sound comes from. The soundhole is so the vibrating air inside the body can help transfer energy to the outside.

When you're using a pickup, the amplified sound gets into the bass via the soundhole and causes the soundboard to vibrate and this is picked up by the pickup and subsequently fed back round the amplification loop. A soundhole cover cuts down on the sound getting back into the bass. It also makes the bass acoustically quieter, but your using the pickup anyway.[/quote]

Cool! That's an explanation that makes my brain happy!