EnABL - Technical discussion - Page 23 - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 27th March 2008, 12:15 AM   #221
soongsc is offline soongsc  Taiwan
diyAudio Member
 
soongsc's Avatar
 
Join Date: Mar 2005
Location: Taiwan
Default Re: wrong thread

Quote:
Originally posted by auplater


... John K's already shown that waves passing over micro-dots don't do anything special.

...
John L.
"Possibly" don't do anything special.
I still think it would be more conclusive if the baffle edge diffraction impulse is compared. Unless someone is trying to determine validity for other applications which we are not aware of.
__________________
Hear the real thing!
  Reply With Quote
Old 27th March 2008, 12:34 AM   #222
ronc is offline ronc  United States
diyAudio Member
 
Join Date: Mar 2003
I am a man of few words, but here is what i see so far.

Everybody is considering the wave energies at various times from the launch, but i believe that this effect has to be early in the wave launch. This is before side lobe formation or even in Fresnel. Its the initial radiation from the launch area which may have less low level noise than an untreated driver.

ron
  Reply With Quote
Old 27th March 2008, 01:52 AM   #223
diyAudio Member
 
Alex from Oz's Avatar
 
Join Date: Jan 2008
Location: Canberra, Australia
Default EnABL Port Test Proposal

G'day All,

Is anybody prepared to apply EnABL to the port of bass reflex speaker and run some measurements?

EnABL Port Test Proposal
- bass reflex speaker (or subwoofer)
- single round port, straight (no flare)
- driver firing into free air (ie. not downward firing)

If so, for transparency, then post here:
- details of the proposed test speaker
- the diamater of the port
- proposed types of measurements (for comment by all)

I will post explicit intruction on how to make and apply the EnABL pattern - including diagrams.

Anybody willing to take this on?
Any comments on the merits of this proposal?

Cheers,

Alex
  Reply With Quote
Old 27th March 2008, 02:00 AM   #224
ronc is offline ronc  United States
diyAudio Member
 
Join Date: Mar 2003
A port is a pressure device. I cannot see in any way how a raised point along the port of a value of .010" can have an effect.

ron

(some sensible physics has to apply)
  Reply With Quote
Old 27th March 2008, 03:40 AM   #225
diyAudio Member
 
Alex from Oz's Avatar
 
Join Date: Jan 2008
Location: Canberra, Australia
Quote:
Originally posted by ronc
A port is a pressure device. I cannot see in any way how a raised point along the port of a value of .010" can have an effect.

ron

(some sensible physics has to apply)
G'day ron,

Neither can I - yet I'm doing consistently.

This is a no brainer way of putting this idea to the sword.

So who's up for it?

Cheers,

Alex
  Reply With Quote
Old 27th March 2008, 03:54 AM   #226
dlr is offline dlr  United States
diyAudio Member
 
Join Date: Mar 2005
Location: Canton, MA
Default Re: Re: wrong thread

Quote:
Originally posted by soongsc

"Possibly" don't do anything special.
I still think it would be more conclusive if the baffle edge diffraction impulse is compared. Unless someone is trying to determine validity for other applications which we are not aware of.
No. NOT possibly. It does absolutely nothing to at least 60db down as measured. Repeat, as measured . Why do you continue to deny the facts? If it did anything at all, it would have shown up in john's measurements precisely where he indicated. Continual denial of the data is becoming rampant.

John's methodology was exactly what is required. The test removed all other extraneous influences. That's the appropriate method. What you think would be more conclusive is immaterial. That's simply an attempt to continue to deny the facts.

Of course if it had shown a change, everyone would be ecstatic about the "proof". The fact is, it showed there to be no change to the wave as it passed over. It's conclusive.

Dave
  Reply With Quote
Old 27th March 2008, 06:14 AM   #227
diyAudio Member
 
Daygloworange's Avatar
 
Join Date: Feb 2008
Default Re: EnABL Port Test Proposal

Quote:
Originally posted by Alex from Oz
G'day All,

Is anybody prepared to apply EnABL to the port of bass reflex speaker and run some measurements?

EnABL Port Test Proposal
- bass reflex speaker (or subwoofer)
- single round port, straight (no flare)
- driver firing into free air (ie. not downward firing)

If so, for transparency, then post here:
- details of the proposed test speaker
- the diamater of the port
- proposed types of measurements (for comment by all)

I will post explicit intruction on how to make and apply the EnABL pattern - including diagrams.

Anybody willing to take this on?
Any comments on the merits of this proposal?

Cheers,

Alex
Alex,

Yes, I will do this and the baffle edge tests. I looked at the Excel sheet you linked to.

I spoke to Al from RAW, he'll do measurements on these as well. We might actually be able to do those before the driver tests.

I need to find out from Al, what size ports and so on he has on hand so we can figure out the size of patterns we need to cut for him to test.

Just busy with work right now, but we will get to do these tests as promised.


Cheers
  Reply With Quote
Old 27th March 2008, 09:00 AM   #228
diyAudio Member
 
Graham Maynard's Avatar
 
Join Date: Dec 2003
Location: UK

""Yes, I will do this and the baffle edge tests.""

AT LAST !
Time to go crack a can !

Good Luck to you Daygloworange, and to Al from RAW.
You are both individuals who still have OPEN minds.


Cheers ....... Graham.
  Reply With Quote
Old 27th March 2008, 09:43 AM   #229
soongsc is offline soongsc  Taiwan
diyAudio Member
 
soongsc's Avatar
 
Join Date: Mar 2005
Location: Taiwan
Default Re: Re: Re: wrong thread

Quote:
Originally posted by dlr


No. NOT possibly. It does absolutely nothing to at least 60db down as measured. Repeat, as measured . Why do you continue to deny the facts? If it did anything at all, it would have shown up in john's measurements precisely where he indicated. Continual denial of the data is becoming rampant.

John's methodology was exactly what is required. The test removed all other extraneous influences. That's the appropriate method. What you think would be more conclusive is immaterial. That's simply an attempt to continue to deny the facts.

Of course if it had shown a change, everyone would be ecstatic about the "proof". The fact is, it showed there to be no change to the wave as it passed over. It's conclusive.

Dave
If this is all true, why not show the baffle diffraction impulse which is much more easily measured. I am not denying the facts, I just think there needs to be data to know what is involved. The fact is when you use MLS signals or impulses to do measurements, the signals have a much narrower angle of radiation so most energy is focused in the front. therefore, to be able to see any effect the pattern height naturally needs to be higher.

My guess is the baffle diffraction cannot even be shown under this condition, and that is why it is not shown. If this is true, then of course we will see almost no effect from the patterns.

Possibly a more effective test would be to just use sine waves low enough that the driver is operating more like a point souce.
__________________
Hear the real thing!
  Reply With Quote
Old 27th March 2008, 10:06 AM   #230
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Quote:
Originally posted by Carlp

As if he's the only one... This is really quite humorous.
Carl

Hi,

I take your point. Probably better not to say anything.
The irony of the style of the post is not easily apparent.

/sreten.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 02:10 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2