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Box speakers with surface mounted tweets

J

jimdgoulding

Registered User
Thought I'd post this capsule to help explain the potential benefit to new browsers (those using conventional box speakers with surface mounted tweets) and revive this information-

Customers recieve this message in addition to mounting instructions in their packets: "All the information your system is capable of resolving from those bits and grooves in your recordings divest itself at the end of the line as sound waveforms. These dense wool pads will insure that the information those waveforms carry is delivered to your listening position free of time and phase error caused by reflection off your speaker baffles (diffraction) not present in the recorded event."

Tis true and definitely worth fixing if you value tonal and spatial realism. Diffraction effects include non lineraity in the frequency response and a smearing of spatial queue's present in good recordings. www.diffractionbegone.com for more info, a couple of pics and some industry and customer comments. Custom fitted and unconditionally guaranteed.
 
Recently received this as a follow up to a larger review posted elsewhere by a fellow using Von Schweikert VR4jr's and VR1's- Two nights ago I had a friend over, a professional musician (bassist), and he was amazed at the realism my system now produces. Said it was the closest he'd ever heard a home system produce what sounds like a live venue. Joe G.

Removing diffraction effects just allows more tranparency to the event is all whatever it happens to be. What I make very effectively preserves the integrity of sound waveforms at their point of departure and what they carry (i.e. the sum total of what your system and investment is capable of resolving). A set custom fitted to your speakers costs $55.95US plus shipping. They work perfectly. Easily mounted with removable Velcro tabs. See the link in the previous post for more info.
 
Bump with a response made just today in another forum bout a lack of understanding about what I make-

Sorry if I didn't make this clear. Longer waveforms are wrapping around box speaker enclosures and being reflected later in time by room boundaries and such. Hence, a reason for room treatment. Shorter waveforms higher up in the frequency response and produced by your tweeter are first interacting with and being diffracted by the baffle and edges of your enclosure arriving just behind the pure signal at the expense of proper time and phase arrival. This would be damped and diffraction eliminated by what I make. The example that previously appeared in my avatar was on a Dynaudio Confidence C4 speaker. I custom fit to a particlar speaker. A Revel M22 appears in my avatar at present. Here is a link to an animated illustration of diffraction in action. You may be able to imagine what you would be hearing without those green and red circles- http://www.silcom.com/~aludwig/images/diffdem.gif

Speaker designer John Dunlavy wrote that the phenomenon known as listener fatique is the direct result of time and phase malady. I observed this to be true in the design stage for myself. The more obvious benefits are improvements to how instruments are rendered and sound. Questions?

I don't think I've posted that link here before. Questions, anyone?
 
KARL- I CAN'T TELL IF YOU GOT MY REPLY CAUSE I CAN'T GET A CONFIRMATION HERE FOR SOME REASON. MY EMAIL ADDRESS IS [email protected]. SEND ME YOUR EMAIL ADDRESS. THANKS.

All- Here is some interesting reading from a guy who was responding to a question posed in a forum elsewhere as to which is worse, diffraction or room reflection and this is what he wrote:

"Driver and cabinet diffraction results in the propogation of delayed signal from virtual sources such as cabinet corners.

This tends to be very early signal errors in the time domain, where the superposition of these signals results in comb filtering and polar anomalies that result in both a smeared direct signal (Ld) - similar, but slightly less than the effects that non-aligned signals and non-coincident drivers create (and where active crossovers with signal delay can play a critical role).

The result is psychoacoustical loss of intelligibility and a modification of the speaker Q due to the modification of the polar response and frequency response (comb filtering).

Is this more critical than the greater delayed virtual sources created by 'larger' room reflections? Simply put: No.

But we are debating similar problems that occur at differing orders of magnitude.

Diffraction effects as Jim is talking about effect the coherence of the direct signal just as the later arriving (generally) first order reflections interfere with the localization and intelligibility and are critical as they are responsible for image shift, and perceived tonal anomalies.

Ultimately, the room does have a greater net effect, but we are still limited by the source, and the total experience will be no better than the sum of the various contributory factors.

Thus it makes sense to address both the design of the speaker as well as the design of the room.

Both are legitimate factors. So they might best be viewed as similar issues, one at the base speaker level, and the other at a 'higher' order of speaker/room interaction".

O.
Senior member

Well said, mate. I can add first hand that even with active crossovers and room treatment the removal of diffraction and its effects is beneficial. And it's so cheap! www.diffractionbegone.com
 
A superb CD for uncompressed music live in the studio with no console in the signal path is Davetik (Mapleshade). Available direct from the label. Explosive drum hits and cymbal shimmer. Like you're at a table nearest the stage in a New York jazz club. You get what the microphone got superbly rendered with real time and place space using my pads.
 
Yo, management. I definitely don't like being relegated to the basement. Did you get some complaints or something? Did it occur to you that with some more discussion and references to accredited sources that members may by and large begin to develop some understanding about what happens using my thing? Was there pressure from other dealers? I am not literally a dealer, anyway, I'm a hobbyist who gets paid a nominal amount by listeners trying to get the most from what they already got. Like myself.

I wish members could see an article about the benefits of getting rid of diffraction in an article, a review, actually, by Robert E. Greene in the most recent The Absolute Sound about the new Gradient Helsinke speakers. REG gave what I make a Golden Ear Award earlier this year. He ain't no dummy. He's a math professor at UCLA in the US. TAS is a hard copy magazine so the best I can do is provide a link to Gradient. They are all about waveform behavior and what it means to your end game: http://www.gradient.fi/models/helsinki

My small thing helps speakers disappear and flattens out the frequency response where it becomes non linear as a result of diffraction, between 2 and 5kHz most generally on two way speakers. Higher up on three ways. It also helps take the room more out of the equation because it provides some directivity so less is being reflected by the near walls. The end game is everything you've invested in, yo. Waveforms are the sum total of everything that precedes them! And what I make is the cheapest way to preserve their integrity on the planet. It's your tweeters that give you information about spatiality and instrumental rendering.

So, I don't know. Either I am in the wrong division, the basement, or in front of the wrong audience. Are you willing to reinstate me in "audio" to give me/members a chance?
 
Hi Jim, the thread was clearly an advertisement, so it just needed to be in the appropriate place. If someone else had started the discussion there would be no issue with your commenting upon it. Full details can be found in the FAQ link at the top of the screen as to how pfm operates. I apologise if this seems a little harsh, but we've had a big problem with viral marketing / spamming recently (I'm not accusing you of this at all) so things which have the potential to be interpreted as a 'pitch' are currently being removed from the general discussion area. I hope this explains matters.

Tony.
 
I can understand, Tony, but the original thread bout what I make in the Audio section was interactive. It's only become nothing but commercial since I was moved. Maybe I'm wrong about that but I'm talkin to myself down here. Got a fair amount of looksies but there is no commentary from others so browsers can only take me at my word. It's not satifying to me but I suppose I'm stuck like Chuck for the reasons you stated. You know, when I paid the fee I was told that my thread would be reopened as is and where it is (was) and because it was conversant that I ponied up. I've tried to reference accredited sources down here for objective information but that's so static. Maybe a customer or two will bail me out. I suppose that is the only available recourse. Thanks for your reply, tho. Jim
 
I can move the thread into the classifieds area if you like, folk can reply to it there. I just can't allow direct advertising in the main room (I never have done), if you've spent much time in there over recent months you will probably realise why I'm clamping down a little! My aim is not to restrict you, just to keep the main audio room advert-free. I'll do what I can to accommodate otherwise.

Tony.
 
OK T, and thanks, but allow me to look around over there and get back to you. Merry Christmas and best wishes for the coming new year, everyone, if yer following our conversation here, or not.
 
Jim, obviously nothing to stop you doing both, i.e. advertise here and chat in the classifieds room! I realise it's a bit clunky and I'm sure we'll think of something better over time.

Tony.
 
Headed on down (boy, I hope that's not indicative) to classifieds. Tony, audio sites on four continents (so far) let me converse in the forum with members and members post their impressions. And don't charge me a frickin fee. I think it's cause they believe there is unique value to what I am doing. Lord knows it one the biggest returns on investment in audio. You can ask my customers! I don't mind the fee- I'm glad to support what you are doing, really, but I do care about the restriction. You seen how many hits are down here? Suggestion . . one site, sorta my home base in the US, has a topic called "Industry Talk" (Audio Circle). Members can exchange with one another and online manufacturers like me. I think everybody is the happier for it. Ironically, the guy that started the site is from Australia. Stereo.net.au is a friendly place down under, too. For your consideration, T.

Currently spinnin . . Blondie.
 
I think thats a good idea. The trade room is limited in that only trade members can post here, some two way communication would be good. It is like that on ZG and Cyrus Unofficial and seems to work.
 
I've stuck a poll up - it allows all trade account holders to decide what they want - I'll happily abide by the outcome.

Tony.
 
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