• 08-29-2007, 11:32 AM
    jim goulding
    This is a rockin post but it preety well describes me
    I make a modest little passive device that may be the best value in audio, at least for those intended. Forget about the "may be" part. Traditional box speaker owners with surface mounted high frequency drivers shouldn't be without it. I describe the science and the effect as best as any 17 year old can in the Speakers-General section of Audio Asylum under the thread name of "Anybody tried this anti-diffraction product?" on 8/29. I dare you to read it and I dare you to tell your friends. Complacency is a thief . . someone said that (my modesty is showing). Cheers.
  • 08-29-2007, 11:51 AM
    jim goulding
    Hi Jim, this is Jim. I think that somebody should reply to your post
    I read. I purchased. And, ever since, every time I sit down to listen, I gloat on how much smarter I am than before I met you. Thanks, Jim. You're a genius! Fellas, and ladies if any are present, don't stop here . . read that stuff!
  • 08-29-2007, 03:55 PM
    Feanor
    You're a genius, Jim!
    Quote:

    Originally Posted by jim goulding
    I read. I purchased. And, ever since, every time I sit down to listen, I gloat on how much smarter I am than before I met you. Thanks, Jim. You're a genius! Fellas, and ladies if any are present, don't stop here . . read that stuff!

    There, it's said. Now maybe you'd be so smart and kind as to post an actual link to the thread in question?
  • 08-29-2007, 04:46 PM
    jim goulding
    okey dokey, fe
    http://www.audioasylum.com

    There is a bunch more info on the line at the site but I can't get it to take. This it'll get you to the Speakers-General page then you can scroll on down to the original query. Yer gettin smarter already!

    Thanks for pullin my coat. jim
  • 08-29-2007, 05:47 PM
    Feanor
    I meant like this
    Quote:

    Originally Posted by jim goulding
    http://www.audioasylum.com

    There is a bunch more info on the line at the site but I can't get it to take. This it'll get you to the Speakers-General page then you can scroll on down to the original query. Yer gettin smarter already!

    Thanks for pullin my coat. jim

    I do believe you're talking about this post ...
    http://www.audioasylum.com/audio/spe...25/254765.html

    For a shill, you could have saved me a search.

    But yes: wool felt is an excellent sound absorber, and I don't doubt that felt sheets will prevent defraction very effectively.
  • 08-29-2007, 09:44 PM
    jim goulding
    I say, old bean . .
    I take you at your word that you appreciate the information, no, that's right, you already knew about diffraction, you just spelled it wrong. I think I was pretty open in this post. I said I make a product. Which some people value cause they've experienced it, either on their own or in my capable hands. Oh, but there I go, shilling again. Before I posted on this particular site, no one had in a very long time. A message of just how long greeted me when I got here. I even answered myself for the fun of it, seeing how I might be totally alone. Well, I'm glad you visited even if you don't get me. And thanks for the link. Seriously, I don't know how to do that for myself. jim

    ps- if anyone should happen to read this and visit my site, be sure and listen to the music (there is a subliminal message in there).
  • 08-30-2007, 11:18 AM
    Feanor
    Consultation
    Quote:

    Originally Posted by jim goulding
    I take you at your word that you appreciate the information, no, that's right, you already knew about diffraction, you just spelled it wrong. I think I was pretty open in this post. I said I make a product. Which some people value cause they've experienced it, either on their own or in my capable hands. Oh, but there I go, shilling again. Before I posted on this particular site, no one had in a very long time. A message of just how long greeted me when I got here. I even answered myself for the fun of it, seeing how I might be totally alone. Well, I'm glad you visited even if you don't get me. And thanks for the link. Seriously, I don't know how to do that for myself. jim

    ps- if anyone should happen to read this and visit my site, be sure and listen to the music (there is a subliminal message in there).

    Diffraction, (did I spell it right this time?), can be reduced a little further in you design by making the cut-out for the driver a something other than a circle, e.g. an oval or rectangle.

    My consulting fees are modest, by the way.
  • 08-30-2007, 02:37 PM
    jim goulding
    Fe, I am aware of these and other designs
    and wanted to talk to you about this as it seemed to me that you are agreeable to some discourse. As I was typing the close, a freakin drop in web page from Aperion Audio took up my entire screen and I could not shrink it. Not having saved the text up to that point, I lost it. That is freakin out-freaking-rageous. Geez, I'm pissed. That's the second time that has happened to me. The first time I thought it was something I had done. Well, I'm gonna take a break. Maybe I'll try to communicate later.
  • 08-30-2007, 10:30 PM
    jim goulding
    Onward and upward . . screw the bastards!
    I am familiar with the designs you mention and perhaps then some. The idea of changing the design to which you refer from a circle to an oval was born out of a need to spread out a wee peak in the frequency response so that it would be less noxious over time. Once this was discovered, I suppose they had to do something. Or, maybe it was just a ruse to introduce a new and improved version and look like a good guy. Don’t laugh, this is done all the time. By the way, I removed some square tracts that came with my speakers after listening to them that way for 8 years. Both these tracts and the aforementioned design were made from neoprene. Neoprene has no acoustical properties. Perhaps, you weren’t referring to a particular product. Rather, your ideas originated with you. Rock and roll, Fe!

    I use a very high grade of wool felt, very dense by design. I do this so the surround is highly absorbent, non reflective. Reflection is the enemy! I fit to the width of a buyer’s speaker enclosure as best I can afford because there is a benefit to be had in smoothing out the frequency response in the frequencies under consideration- two independent tests show this happening- and reducing the amount of energy hitting one’s side walls.

    A fellow provided me with some home made round surrounds with pie shaped cutouts around the inside circle. While I think this communicates versatility to the prospective buyer, a good thing if you want to move some product, I don’t hear it. Two things . . I use a bigger cutout so nothing vital is being grabbed and I use a much higher grade of felt. The lower the grade the more synthetic fiber is mixed in. Rayon is typical, itself reflective. The interior points of the circle were quite a bit closer to the intended driver. In his case and with what he was using, I believe this is a good idea.

    In the General Audio section there is conversation going on about the state of AR. What do you think of having someone doing a review of a member’s product for the interest of readers? My product, for example, but perhaps there are other members who may have a mod or a bonafide product they would submit.

    I’d like to do articles, as well, to include a record review I have completed for this purpose and would like to read the efforts of other members on just about any subject.

    Remember what I told you in the previous reply about having the “post a reply” page hijacked from me? I foxed em this time. I typed this in Word and copied it to the page in about 2 seconds. You can’t keep a good man down!:crazy:
  • 08-31-2007, 05:41 AM
    Feanor
    Yes, that's about it
    Quote:

    Originally Posted by jim goulding
    I am familiar with the designs you mention and perhaps then some. The idea of changing the design to which you refer from a circle to an oval was born out of a need to spread out a wee peak in the frequency response so that it would be less noxious over time. Once this was discovered, I suppose they had to do something.
    ...

    I use a very high grade of wool felt, very dense by design. I do this so the surround is highly absorbent, non reflective. Reflection is the enemy! I fit to the width of a buyer’s speaker enclosure as best I can afford because there is a benefit to be had in smoothing out the frequency response in the frequencies under consideration- two independent tests show this happening- and reducing the amount of energy hitting one’s side walls.

    ...
    I typed this in Word and copied it to the page in about 2 seconds. You can’t keep a good man down!:crazy:

    "The idea of changing the design to which you refer from a circle to an oval was born out of a need to spread out a wee peak in the frequency response ..." That's about the way I heard it, or perhaps more precisely, that a perfect circle inherently produces a very stronger diffraction pattern affect certain frequencies. Some vendor explained it that way but I don't remember who it was.

    I don't doubt the wool felt is a much better absorber than whatever foam it was he was using, hence shape is less important. Nevertheless there must be some reflection, so the concept remains.

    Good idea to edit lenthy reponses in Word or some off-line editor. For my part, I try to keep my responses succinct.
  • 08-31-2007, 07:21 AM
    jim goulding
    Thanks for your reply, discourse is a good thing
    The concept is valid when the substance is reflective. No peaks could be seen in the graphs I refered to, just the opposite. At any rate, what I think I hear is a greater sense of realism when a recording isn't too truncated by sound engineers in the first place. I'ts like you just know that things are right on some level. And you relax. I submit it's because they are. The mechanics, hence, the sound. I've been on the receiving end of several conversations about the science taking place with the technical editor of Positive Feedback online. She tells me that she will be writing an artcle on this in that publication soon. She's also sending me some drawings for a speaker the she and her husband are designing for me to design some surrounds that will be a part of production.

    I'm glad, for sure, but my ambition is to bring this to the mass of box speaker owners to enliven their sound in their environment.

    But there I go, you know. Thanks, Fe, for your input and your awareness. jim