Stick on foam around tweeters?

0 Members and 1 Guest are viewing this topic. Read 11654 times.

ASCTLC

  • Jr. Member
  • Posts: 82
Stick on foam around tweeters?
« on: 23 Jul 2015, 03:17 pm »
I see speakers on occasion which have foam on the sides of or around tweeters.  My VMPS Tower IIs had this.  I'm assuming this is for controlling/minimizing dispersion when one can't do anything more about side reflections from walls/ceilings/floors?

Is there something special about this foam or is there a source for something like this in many craft type stores?

I ask because I get a bit of reflection from my fireplace, wall, and window.  I'll keep this concise, it's either live with it or try some of that foam if that's what that stuff helps with.

Thanks,
Andy

mresseguie

  • Full Member
  • Posts: 4736
  • SW1X DAC+ D Sachs 300b + Daedalus Apollos = Heaven
Re: Stick on foam around tweeters?
« Reply #1 on: 23 Jul 2015, 03:28 pm »
Hi, Andy.

I believe that is actually felt rather than foam. I'm afraid I've never experienced it first hand, so I can't tell you anything about it other than it is supposed to improve the sounds emanating from the tweeter.

Michael

S Clark

  • Full Member
  • Posts: 7365
  • a riot is the language of the unheard- Dr. King
Re: Stick on foam around tweeters?
« Reply #2 on: 23 Jul 2015, 03:28 pm »
We have an AC member, Jim Goulding, that makes a dense wool tweeter surround custom to fit your speaker.  Search for DiffractionBeGone.  Good results for a very cheap tweek... and Jim's a good guy.

ASCTLC

  • Jr. Member
  • Posts: 82
Re: Stick on foam around tweeters?
« Reply #3 on: 23 Jul 2015, 06:00 pm »
Thanks guys.  It seems results are subjectively similar to changing power cords, wall sockets, fuses, etc...no real consensus but I'd like to test for myself.  That's why I was thinking of a cheap, local source of a product (even if not the absolute most effective product) that would give me some idea if there's improvement to be made in this area of my speaker's performance before going all out.

Andy

srb

Re: Stick on foam around tweeters?
« Reply #4 on: 23 Jul 2015, 06:16 pm »
You can get some felt at a craft or fabric store for a few dollars to try it before buying ones that might look and work a bit better that would be precision cut from premium felt.

Steve

arthurs

Re: Stick on foam around tweeters?
« Reply #5 on: 23 Jul 2015, 06:36 pm »
I have a pair of Jim's surrounds from a previous speaker.  You're free to try them out if you want, I don't use them anymore.  Only cost you $5 for shipping.  Kidding, I'll just send them... :D

rajacat

  • Full Member
  • Posts: 3239
  • Washington State
Re: Stick on foam around tweeters?
« Reply #6 on: 23 Jul 2015, 06:46 pm »
Here's a source for quality wool felt.
http://www.mcmaster.com/#felt/=y6i2s5

JLM

  • Full Member
  • Posts: 10666
  • The elephant normally IS the room
Re: Stick on foam around tweeters?
« Reply #7 on: 23 Jul 2015, 07:17 pm »
Doubt if a thin piece of felt will fully address your issues around fireplace, wall, and windows.

WGH

Re: Stick on foam around tweeters?
« Reply #8 on: 23 Jul 2015, 09:22 pm »
Foam worked fine on my old Von Schweikert VR2 speakers. Imaging was enhanced, probably a combination of lessening diffraction at the speaker cabinet edges and changing the side wall reflection point. The foam was 3/8" thick.



Wayne

S Clark

  • Full Member
  • Posts: 7365
  • a riot is the language of the unheard- Dr. King
Re: Stick on foam around tweeters?
« Reply #9 on: 23 Jul 2015, 09:44 pm »
Doubt if a thin piece of felt will fully address your issues around fireplace, wall, and windows.
No, but I've seen the before and after measurements of felt/foam around tweeters, and they can do a nice job of smoothing out diffraction ripples.  I've also got some extra 1.5"x .5" felt strips that were used on a kit that I built.  I can put some in an envelop and send some.  Jim's stuff is still better due to higher density than the stuff I used, and mine is pretty dense.  If you want to try it out, send a PM.
Scott

ASCTLC

  • Jr. Member
  • Posts: 82
Re: Stick on foam around tweeters?
« Reply #10 on: 23 Jul 2015, 11:05 pm »
Nice responses and great generous offers guys!!  :thumb:   Getting to try this and using Jim's stuff makes for an awesome day for me!  And Clark's offer is no less generous!

JLM, I wonder just how much it might help too, thus the need to try some level of experiment first (if possible).

Andy

charmerci

Re: Stick on foam around tweeters?
« Reply #11 on: 24 Jul 2015, 12:10 am »
I've found that sticking on thicker pieces seems to reduce the soundstage, i.e. (higher frequency) sounds tend to come from the area of the two speakers rather than placed somewhere in the middle. There's probably some middle ground.


I think if you don't care how your speakers sound, it won't make it better. If there just one small area of high frequency range that you don't care for, it can help. My .02.





DS-21

  • Full Member
  • Posts: 334
Re: Stick on foam around tweeters?
« Reply #12 on: 24 Jul 2015, 03:06 am »
See http://www.speakerdesign.net/audioXpress/diffraction/diffraction.html

That said, felt/foam will make a well-designed speaker worse, if it wasn't designed with it. But for better or worse, most "audiophile" speakers aren't well designed, so one can't really say what kind of effect it will have.

KR500

  • Jr. Member
  • Posts: 222
Re: Stick on foam around tweeters?
« Reply #13 on: 24 Jul 2015, 11:45 am »
I installed  thin fabric pull down shades on the 2 living room windows .
Really made a difference in smoothing out the pings off the glass from the speakers at the other end of the room

fredgarvin

  • Full Member
  • Posts: 1332
Re: Stick on foam around tweeters?
« Reply #14 on: 24 Jul 2015, 03:27 pm »
It can be hit or miss depending on the speaker. A lot of designs now feature tweeters with built in waveguides. The dense foam VMPS used on many models worked in a similar manner. Removing them has a detrimental effect on the horizontal dispersion.

arthurs

Re: Stick on foam around tweeters?
« Reply #15 on: 11 Aug 2015, 12:13 am »
Well Andy?  Any results?  Curious cats want to know!  :-)

Donald

  • Jr. Member
  • Posts: 117
Re: Stick on foam around tweeters?
« Reply #16 on: 11 Aug 2015, 01:02 am »
Isn't this what Dunlavy years ago did?

steve f

  • Full Member
  • Posts: 682
Re: Stick on foam around tweeters?
« Reply #17 on: 11 Aug 2015, 04:38 am »
Yes Dunlavy used a felt ring that had kind of a sunburst pattern for the opening. I believe Wilson has done arrangements.

ASCTLC

  • Jr. Member
  • Posts: 82
Re: Stick on foam around tweeters?
« Reply #18 on: 11 Aug 2015, 12:47 pm »
Sorry, haven't been able to perform it yet Art.  We have a couple contractors finally showing up and I've been bustin it trying to get my part out of the way.  That combined with the torrential rains we're getting in the afternoons/evenings stopping my tractor work time, I'm way too distracted to test this.  I get stopped and can't stop my mind planning how I'm going to get it done.

I know I don't have the ear many of you guys do so anything short of total focused concentration and I don't know that I'll be able to tell.  They're here right beside me on my desk begging to be implemented.

Enough excuses, your generosity deserves I carve the critical listening time to get with this in a timely manner.  I will get this done this week!  And I'll post back my impressions.

Steve, I found a very excellent pair of Signet SL280B speakers for my garage system and it has those star cutout foam surrounds for the tweeters.  It was those and the remembering my VMPS speakers having foam that got me on the path wondering if it might help with my current speakers.



Andy

ASCTLC

  • Jr. Member
  • Posts: 82
Re: UPDATED - Stick on foam around tweeters?
« Reply #19 on: 14 Aug 2015, 02:16 pm »
As promised, we got it done.

With my wife's help yesterday evening we settled down and got into our frame of mind to evaluate the application of the wool felt around the tweeters.  Wasn't the easiest thing to do because of the square shape of the ribbon tweeters and that they are part of the ribbon mids (as seen below).

So we started out with some light listening of Steve Miller Band, Fly Like An Eagle.  At first just sitting back enjoying it, then increasing our focus on critical listening of the various instruments until we were satisfied we had a good "feel" for the sound and our listening attention.

To see what difference we could detect, we had to give attention mostly to one speaker, the one over near the fireplace.  We tried it first with no felt around the tweeter of the other speaker, then did the same testing with no felt around the other speaker - just in case it might matter.

I sat in my chair with remote in hand, eyes closed while my wife stood behind the speaker.  Without being a ported speaker and large enough for her to actually stand behind without affecting the upper frequencies enough, I had her put the felt around the tweeter section while I listened a moment.

When I thought I was really focused on the sound I'd motion to her I was ready.  She would wouldn't just remove the felt when I motioned, she'd pull it some time after she knew I was "into it".  With my eyes closed, she'd remove the felt and watch for my reaction to see if I could detect any change in sound.  Through numerous tests, I never reacted.

We agreed that without indication, notice, or noise, from her behind the speaker the felt would be removed and only the listener would give any indication of a change by initiating a response, if anything was noticed. 

We tried doing it at different volumes too.  My system opens up and comes alive just a little more once it hits a certain power level.

She has a pretty decent ear and honest too.  So we went through all the same testing for her and she never could detect any change whatsoever.

What I found difficult was trying to listen critically to instruments but then having to change focus and listen to the music.  I listened to instruments to see if something in the highs could be detected, but believing I'd miss the forest for the trees, I had to adjust to listening to the entirety of the music.  In the end, it's the entirety of the music that I wanted anyway and would endure lasting enjoyment.

We detected no benefit, detraction, nor change from the felt - zip, nothing, nada.  Is it the awesome tweeter design, is our room just not conducive to that tweak, or is are our ears just too unrefined as many here?  Beats poo out of us! 

Was this a failed test?  Not even close!  While I'm no trained ear or method tester, we did what we could, with what I figure is the best possible product for this that had been so generously donated to us.  Does this mean felt tricks around tweeters is hoopla? Oh, I seriously doubt it.  These are our speakers, in our room, with our ears - not your speakers, your room, and your ears.  If someone find successful improvement doing this with theirs, then that is cool.  Good for you/them for finding improvement by something so simple to implement.

My conclusion: Not only was this not a failed test but a total success!!  Knowing there's no improvement to be found in tweaking them (room treatment where possible is another story) has only been further solidified.  We could find changes in source equipment or possible room treatment, but the speakers themselves are there to stay knowing there's nothing to do with them.  Now we can go back to just sitting there enjoying our music and try not to pee in our seats as relaxation and big grins overtake us   :D

Andy

« Last Edit: 14 Aug 2015, 04:45 pm by ASCTLC »