Beam blocker type thingies

[richard parker]

There's been a fair bit recently about beam blockers and acoustically absorbent foam doughnuts etc. I've read that the most basic way to address the high beam issue is to stick a piece of tape over the speaker grill. I'm sure I've read that SRV sometimes did this.

Anyone tried it ? With what result ?

 

[Lake Placid Blues]

Re: Beam blocker type thingies

I've taken a piece of foam and glued it to the grill cloth right in front of the speaker center before. The piece of foam being about the diameter of the speaker dust cap. It's not a donut but a donut center. It does help take away some the icepick effect. Its noticable. Which was my goal. It doesn't make the off axis and the on axis sound more or less the same, which appears to be the goal of the donut approach. The thing about these things are that they cheap and easy to try. Duct tape is certainly the cheapest and easiest. If doesn't work for you, its nothing lost and reversable. Can't hurt to try it.

 

[Laughing Kookaburra]

Re: Beam blocker type thingies

I used a circle of cardboard that was a tad bigger than the spkr cap, and duct tape in an X pattern to secure it. Worked well enough in reducing the icepick.

Like Lake Placid Blues points out, it's cheap to try, and reversible.

 

[GoDrex]

Re: Beam blocker type thingies

I'm not about to put duct tape on my speaker grill. Duct tape usually leaves its glue behind.

 

[GuitarDoc]

Re: Beam blocker type thingies

IMHO, the Beam Blockers are the best solution. They evenly distribute the highs so there is no spike right in front of the speakers. The foam idea removes the highs. Acoustic foam absorbs high frequencies, a piece of cardboard (either a Beam Blocker or cardboard taped to the grill) reflects and redirects the highs. That is why acoustic foam is used inside ported cabinets...so only the bass goes through the ports to reinforce the low end.

So you have to answer the question...Do you want to remove the high frequencies from your tone, or just evenly disperse it so there is no spike right in front of the cone?

I've got Beam Blockers and they are terrific. They do exactly what they are intended to do and they do it well.

 

[theunknown22]

Re: Beam blocker type thingies

I bought beam blockers and they buzzed when I put them in my Marshall 1936 cab.

 

[GuitarDoc]

Re: Beam blocker type thingies

I bought beam blockers and they buzzed when I put them in my Marshall 1936 cab.

Must not have tightened them down tight enough or evenly.

You actually have to tighten them in stages over time so you don't warp the speaker cage. Put them on and tighten the screws going through the spkr and BBs very tight. The other two screws through the spkr are just tightened lightly, evenly. Let it sit overnight to settle into the spkr gaskets, then tighten every screw fully. You may have to come back later (in a few weeks)and retighten everything again as the BBs settle into the spkr gasket..