"Beam Blocker" question:

Pete Burak · From: Portland, OR USA

As per these links: http://www.guitarplayer.com/story.asp?storycode=11734 http://www.webervst.com/blocker.html

'Sounds like the Beam Blocker is basically a paper dustcap attached to a mounting bar.
'Question for anyone who has one... How is the dome attached to the mounting bar? 'Got a picture?

Also, How do you rate the effectiveness of this unit with regard to reducing the ice pick highs produced by some Fender-amp/Speaker combo's?

In my case, I am trying to tame the highs of a '76 Fender Vibrosonic with Original Orange frame JBL (sounds great for guitar, too shrill for steel).

I figure I can make one myself just to try the concept. Plan B is to get an EVM15L or some such type speaker. I am hoping to try a Kappalite 3015 (neodymium magnet - only 8 lbs) speaker too.

Thx,
Pete B.

Bari Smith · From: Spartanburg SC USA

Put a square of gaffers tape on the grillcloth,in front of the cone,play for a while then remove it ..you can tell a difference.

------------------
SHO-BUD LDG,Carter SD-10,Webb 614E,Dobro

David Doggett · Posted 8 Nov 2006 11:22 am

Pete, I don't have one, but it looks like the Beam Blocker is more like a cone shaped baffle than a paper dust cap. The higher the frequency, the more directional the sound wave. I don't think a Beam Blocker will have much effect on the general bright sound of a JBL with an aluminum dust cap. The domed shape of the dust cover helps spread the highs around somewhat. But because the speaker moves straight back and forth, there is a piercing narrow beam that goes out dead center to the speaker. That is what the Beam Blocker is designed to baffle, not the entire high spectrum in all directions.

JBLs are my favorite speakers for my Fender tube amps (Pro, Dual, Super Twin). I just don't get that sparkle and definition in the highs with other speakers. I think part of it is not just the aluminum dust cap, but the fact that JBLs are low wattage speakers (about 60 watts) with cones that are not particularly thick and stiff. But with the JBLs I keep the treble between 2 and 4, otherwise they can be too shrill. I also have an Eminence speaker that is rated over 200 watts and has a paper dust cap. It just doesn't sound as good to me as the JBLs, even for jazz, where I like a mellow tone. It goes from muddy to honk, but there is no sparkle there, no matter what I do with the EQ. I had an EV 12" with an aluminum dust cap in a Princeton Reverb II. It was supposedly a JBL clone, and it sounded great.

Jon Light (deceased) · From: Saugerties, NY

Pete---it's all about directionality. Laser beam ice picks. It won't tame the highs but it will help to keep from killing that certain someone that your cab is pointed at. And it will help even out the real sound----what you hear a few degrees off axis (and ideally, even more than just a few degrees) will be more like what you hear dead on. Dispersal, in other words. I find it to be effective but not miraculous.
The 2nd photo doesn't give a great view of the hidden side--I just can't get an angle at it.

Donny Hinson · From: Glen Burnie, Md. U.S.A.

I'm more likely to go for a simple solution, like turning the treble down, or changing to a speaker with a paper dust-cap.

Pete Burak · From: Portland, OR USA

I assumed it was a dust cover from what it says in that link:
"A heavy paper dome (which is actually a dust cap that Weber borrows from its speaker component inventory) is glued to a steel center disc."

Since putting an EVM-12L in my Deluxe Reverb I can use pretty much the full range of the Treble knob without issue. I know that 2-4 is typical with the JBL, but I'm hoping to get a 15" speaker with characteristics that will let me use the Treble knob more effectively.

The Beam Blocker thing came across my field of view again yesterday, so I thought I would ask. Looks easy enough to make at home for a quick trial.

Thx for the inputs (and Pic's, Jon).
Pete B.

Larry Robinson · From: Peachtree City, Georgia, USA

I tried a beam blocker with a weber california which was extremely harsh sounding. I did not notice any appreciable difference. I tried various EQ settings on the amp but just could not get any satisfaction. I sold the Cali, gave the beam blocker to my grandson and installed a genuine JBL D-120 and all was cured. Nothing sounds like a JBL except a JBL.
Larry Robinson

Brint Hannay · From: Maryland, USA

For many years I've used a cardboard disc for the same purpose. I just cut out a disc a bit bigger around than the speaker's dust cap from a pizza box, stuck a velcro strip to it, and stuck the other velcro strip to the inside of the amp's grille cloth, centered over the speaker. Press on the disc, and voila! Being on the inside of the grille cloth, it's barely visible. The disc has never fallen off (it's been there at least 10 years)--the adhesive on the velcro is strong. It's crude but effective--both I and others can definitely tell the difference in speaker beaming.

Mike Fried · From: Nashville, TN, USA

I use a Weber Beam Blocker (the largest size)on my Webb with a Black Widow and there's an obvious improvement, an even dispersion of the highs so that I'm able to sit close to the amp but off-axis from the speaker and hear a more accurate "picture" of the speaker. Also, it helps in miking the amp as its position along the cone is not nearly as critical (as long as it's not pointed at the beam blocker, of course). You don't get that from turning down the highs or using a paper dustcap, that's why people are using them...

Jim Sliff · From: Lawndale California, USA

Larry, was your California a paper or aluminum dustcap model...or the newer large one? I'm curious how new the speaker was as well. All my Californias have been a little harsh out of the box but really warm up when broken in. Much less "icepick" than any JBL (and I've had dozens) - even the Weber aluminum model.

I've made my own "beam blockers" for years, and it's very effective in front of the speaker, which is exactly what it's designed to do. If your amp is on the floor and you're off-axis 30 feet away you won't notice - but people in front of it will, and so will a soundman miking it.

Back to the treble issue - you can't test the effectiveness of a beam blocker on a brand-new speaker. Get about 10-20 hours of playing on it, then it'll make a difference...because the speaker will be broken in and not pushing so hard on the high frequencies as they do when new.

Larry Robinson · From: Peachtree City, Georgia, USA

Jim, I had the ceramic Cali w/Aluminum dust cover. I bought a beam blocker from Weber and installed it. I played the speaker for about 2o hours before I sold it. For my taste, the speaker was just harsh sounding. I don't play steel though. I own a Gretsch and Carvin solid body I've had over 20 years. The speaker was SS Peavey amp. I bought an electro-Voice EVM-12 and the sound came alive for me. I recently found and bought a JBL-D120F original cone. This gives me the sound I remember when I bought the brown tolex covered Vibrasonic (or Vibrosonic) back in '62 that had a D-130 in it. Maybe I didn't give the Cali enough break-in time. My current amp is an Evans AE-100 with the JBL as an extension.
Larry

thurlon hopper · From: Elizabethtown Pa. USA

Pete i tokk my '73 Vibrosonic to an amp tech and he changed several components inside that made the equalization controls on the amp more sensitive. Don't recall what all he changed but D-130 just seemed to liven up. I sold it because i couldn't carry it around but that was probably the best sounding amp i've ever plugged a steel guitar into. The Twin that i own now is also very good and i'm using different speaker combinations with it. The best overall sound, highs, mids, lows comes from my Altec 4178H but the JBL is really hard to beat.

Jim Sliff · From: Lawndale California, USA

Larry - yeah, it probably needed more break in - but to me, a SS amp with an aluminum-dome speaker is going to have nough trble to scalp you. Not my favorite combination.

James Quackenbush · From: Pomona, New York, USA

If you're not likin the tone of the JBL, there is not much you can do to change it , other than change out the speaker ...The EV12L or 15L is a darker speaker , and is very efficient ....It will probably do the trick for you ... You either like JBL's or you don't like JBL's .... The JBL 10's that came in some Blackface Super Reverbs are even BRITER !!!.... Jim

[This message was edited by James Quackenbush on 10 November 2006 at 01:41 PM.]

Jon Light (deceased) · From: Saugerties, NY

Just FWIW, I have two cabs, one with a D130F and one with a 15" ceramic Cali (with paper cone) that I have A/B'ed. The JBL is actually in a better sounding cab. I find the two to be similar sounding (as they should be, the Cali being modeled after the JBL even though the JBL is alnico and this Cali is ceramic) but I prefer the Weber speaker, even in its less resonant cab. It is more even across the spectrum. The JBL has more peaks/spikes (as I imagine it would look on a graph.) This may be a characteristic that appeals to fans of the JBL. Could be that if it were all I had I would grow to love it too. Totally subjective but that's my impression. The Cali is well broken in.

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