Golden Ear award for $55 speaker tweak


In the latest issue of The Abso!ute Sound, Robert E. Greene honors "Diffractionbegone" with a Golden Ear award. Quoting from the text (page 36 of the June/July 2008 issue): "If your speakers suffer from tweeter diffraction-effects, these elegant and inexpensive felt devices will make an improvement all out of proportion to their low price."

Diffraction can degrade not only imaging and timing but also clarity. You see, the ear is very good as masking (ignoring) a coloration that arrives at the same time as the original signal, but it is very poor at masking when the coloration arrives at a different time (I learned this from conversations with Dr. Earl Geddes). This product addresses several real, audible problems that are present in most speakers.

The felt pads are custom-cut for your specific speakers, which is a nice touch and pretty amazing at the price. And note that this is by far the LEAST EXPENSIVE product to be singled out for a Golden Ear this year.

http://www.diffractionbegone.com/

Congratulations to designer and entrepreneur Jim Goulding. I think he sells them through Audiogon as well as through his website, and it looks like the price may actually be only $49.95 plus shipping. Support your local 'Gon and buy through the site. Come on - you probably blew more money than that on shipping last time you bought or sold a pair of speakers! I sure did.

Duke
dealer/manufacturer/no affiliation with diffractionbegone
audiokinesis
Duke, it’s a great subject. Vandersteen speakers have all used felt around their tweeters since 1977. No need to tweak lol. 
My Raven CeLest rowers come with a a high frequency wave guide.

Sound is awesome from these speakers. Just wonderful.
When I had my own shop, and designed my own speaker line: The systems that didn't incorporate a ribbon tweeter had the Peerless 1" dome(this was started in '81). I always added a 6" foam donut w/a 3" hole around the dome. They never rolled off the highs. Just got me a lot of compliments on their imaging. Cabinet diffraction and how to combat it is old, but still viable, science.
All of which is, of course, proof positive of Robert E. Greene's abso!utely impeccable taste and insight

LOL.

To add to the list my old 1982 Energy 22 had a rubber foam around the hyperdome tweeter and they did indeed image like no tomorrow.

Since it is indeed nothing new - why do so few people not bother about it - is it just another case of aesthetics wins over sound quality?
Jax2, yes I also received a Golden Ear from Robert Greene in the same issue. Interestingly, of the four products he honors thusly, I am or was a dealer for three of them! Diffractionbegone is the only one I've not been affiliated with. And all four are products that specifically address loudspeaker radiation characteristics.

All of which is, of course, proof positive of Robert E. Greene's abso!utely impeccable taste and insight.

Duke
works for me i use 1/4 thk rubbery foam (similar to wet suit)on my psb goldi i got for detail and focus. for scrap material around the house not mad at all .
I think my experience captures some of the earlier posts. A poster with the moniker "Bald Eagle" at the Vintage Asylum at Audio Asylum suggested this tweak. I bought some self-adhesive felt at Home Depo, sized it, and placed it along the sides of the tweeters of ADS L710s I used to own to a height of about 1/2-3/4 inch. I believe that the sound improved.
Installing felt around the tweeter is old hat. It's a simple effective way to roll off the highs. I considered doing it on my Aerials when I had a Krell.
Looks like what many speakr manufacturers have been doing for a while. Wilson Audio is one example
While I use a felt material on my VMPS I installed last year, I was inspired by my 25yr old Teledyne AR9 speakers so its not new or any revolution but all the same is beneficial........you can buy adhesive felt sheets at a hoby store or even at Walmart.
Those look like what Spica used to use on their TC-50's (I'm sure I've seen the same thing on other speakers as well). I can't help but think it looks an awful lot like the stuff you can get for your furniture at Home Depot to prevent scratching the floor. Man, Home Depot's becoming a regular audiophile resource center! Hey Duke, I seem to recall seeing your statement speakers on someone's Golden Ear list in this issue too. Correct me if I'm wrong, but if so a big congratulations to you! That's a pretty significant achievement.

This is from the website

Sound waveforms from your tweeters are shorter in length than the width of
your speaker cabinets. A 2000Hz waveform is 18cm or 7" in length, for
example*. We hear information up to approximately 14kHz on average. These
waveforms are being randomly reflected by your speaker baffles and edges to
your listening position slightly out of time with the original event. Not a good
thing. These waveforms carry the first arrival and higher harmonics of your
midrange along with all things high frequency. Our product removes this
almost as if you had taken the boxes away.

We size to speaker and professionally cut high density real wool felt (accept
no substitute) tweeter surrounds or fascias that absorb and quiet this
interaction.

Unlike other many other tweaks - the science behind this is not flaky. THIS IS REAL. The improvements are described as;

What you will get when this is removed is a clearer view into your
stage and recordings. What the microphone captured is revealed in your
room without the distortion to time (body) and phase (space) caused by early
reflection. Space opens up, deepens. Vocals and instruments appear more
truthfully in that space, rounder and more physically right.

This accurately describes what I gained when I soffit mounted my speakers into a wall and made them flush with the wall with a smooth transition (totally eliminating baffle edge diffraction altogether). This is why all high end main monitor sound at a major $multi-million recording studio facilities is soffit mounted (in the walls - and they have been doing this for decades!!).

This sounds amazingly cheap for something that will certainly reduce edge diffraction from sharp speaker baffle edges. I doubt it will eliminate totally the problem but I believe the reduction will be audible in most cases.

For $50 bucks what do you have to lose - try it and perhaps you will be so impressed that you will be designing a soffit mount for you next set of speakers!

Only caveat that I see is that this will certainly change the dispersion pattern - so you may be compensating for something the speaker designer has already considered (for example why else do you see tweeters offset from center? - because this mitigates horrible edge diffraction issues)