My new Scoop design
Printed From: Speakerplans.com
Category: Plans
Forum Name: New Projects Forum
Forum Description: Forum for new speakerplans projects, in memory of Tony Wilkes, 1953 - 2014
URL: https://forum.speakerplans.com/forum_posts.asp?TID=3999
Printed Date: 27 March 2026 at 4:06am
Software Version: Web Wiz Forums 12.08 - https://www.webwizforums.com
Topic: My new Scoop design
Posted By: mykey
Subject: My new Scoop design
Date Posted: 22 February 2006 at 12:22am
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http://img158.imageshack.us/my.php?image=untitled8gw.png"> My new 18'' Scoop design! comment's please? please excuse the messy drawing ------------- ......just all them hanging there like giant bananas. |
Replies:
Posted By: Joe Grime
Date Posted: 22 February 2006 at 4:18am
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It will never catch on Steve |
Posted By: ceharden
Date Posted: 22 February 2006 at 7:04am
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Just needs to be trapezoid as well to eliminate any parallel walls and you'll have a practically unbuildable cab! I can see what you're trying to do but since scoops have issues going up in frequency, making it all nice and smooth is probably unnecessary. Nice idea tho. |
Posted By: bartsegers
Date Posted: 22 February 2006 at 12:19pm
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why retry an already desigend cab? in my eyes scoops are completely dead-designed |
Posted By: Matthias
Date Posted: 22 February 2006 at 2:43pm
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hey mykey, thats what i thought of, too. the round corners only can make the sound better, but i dont know if the triangle section is needed. bracing is important too. im not an expert, but the difficult way of rogs design isnt for fun i think. so i will read this topic carefully |
Posted By: freddyi
Date Posted: 22 February 2006 at 2:46pm
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shouldn't lowpass function be "better" than attempting wideband rear
wave augmentation? - just curious - what would the smooth curve do to
summed response? btw - here's Bill Woods' mini scoop vs JBL C40 http://gallery.audioasylum.com/cgi/gi.mpl?u=21168&f=UPWARD.gif - http://gallery.audioasylum.com/cgi/gi.mpl?u=21168&f=UPWA RD.gif |
Posted By: Jay Lawless
Date Posted: 22 February 2006 at 2:54pm
last i heard a smooth curve would give more of smooth roll off on the
bass end making it a nice pleasent sound. while straighter angel gives
a hard kick. but thats dealing with the horn mouth. the curve is great
when trying to get precise sounds, but i personaly go for the straight,
gota love the kick.
------------- Previously known as NeverWinter Background: Automotive, Live and Home Custom Design. mid/high level based design and feild experience. Bass specialist |
Posted By: minaximal
Date Posted: 22 February 2006 at 3:36pm
straight angles act as a band pass, smooth curves will lessen this affect. straight sections are conical approximations of ideal flare rate and thus will have a more peaky non linear response. much as i love curves i would think, it may create even more cancellations than a normal scoop around 80-100hz as freddyi pointed. @mykey whats your goal, done any tests yet? is this a new xxl offering? |
NeverWinter wrote:Posted By: mykey
Date Posted: 23 February 2006 at 2:58am
who has? can i see any pic's? thanks for your comment's guy's most appreciated the cab is pretty easy to build actualy.. all the curves are mostly one piece and are made on pneumatic jig's and i use a 30 second 2 part glue @mykey whats your goal, done any tests yet? is this a new xxl offering?
Testing them next week up against my old design, ill let you know guy's Thank's again ------------- ......just all them hanging there like giant bananas. |
Posted By: bartsegers
Date Posted: 23 February 2006 at 11:27am
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improvement is the idee. I thought you were re-inventing a scoop. no comments then.
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Posted By: Phil B
Date Posted: 23 February 2006 at 2:35pm
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Well....if you made it trapezoid it`d be petty close to these...
http://www.speakerplans.com/index.php?id=myplay_080 - CMC Matrix scoops Which were designed and built by NCA. They use the " no hard corners " philosophy on all their bins and the scoops were no exception. All smooth curves and constant flare rates ...blah blah...loaded pd1850`s ..etc etc Anyway CMC sold `em on ....seen some of them about at carnival last year. Looks like the driver is right up to the rear chamber divide..? So a smaller rear chamb` and longer horn length..? Should be " smoother " than most scoops anyway! .p. ------------- Mostly harmless.... except if catering is shut. Solar Sound System Shennanigans.. http://diyhifi.biz/" rel="nofollow - http://diyhifi.biz/ |
Posted By: Joe Jones
Date Posted: 25 February 2006 at 10:14am
| Curves look pretty but below 200 Hz they really don't do anything. Scoops are a dead issue in any event. The dispersion of the large woofer limits its usefulness to perhaps 400 Hz, and the rear horn is too short to go below 60 hz or so. That's far too narrow a bandwith to justify such a large box, especially in the bass. Something this size shouldn't need to be paired with a sub. |
Posted By: Tom Umney
Date Posted: 25 February 2006 at 9:24pm
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LOL anyone who uses scoops above 150hz must be mad. 400hz out of scoops would sound like sh*t. 18 inch scoops are fine for dub,reggae and dnb. And 4 will do from about 40hz- 150hz.
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Posted By: mykey
Date Posted: 26 February 2006 at 6:48am
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ill be crossing them over at 80. a sigle 15 x-tro will go above ------------- ......just all them hanging there like giant bananas. |
Posted By: Phil B
Date Posted: 26 February 2006 at 7:59am
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We always crossed ours at 80hz low pass and 35hz high pass....?
"Curves look pretty but below 200 Hz they really don't do anything.".....whatever... .p. ------------- Mostly harmless.... except if catering is shut. Solar Sound System Shennanigans.. http://diyhifi.biz/" rel="nofollow - http://diyhifi.biz/ |
Posted By: Joe Jones
Date Posted: 26 February 2006 at 9:48am
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"ill be crossing them over at 80" ????? The point of a scoop is to use the midbass from the front wave, and you're not going to use it. From the same size box you could use smaller drivers in a spiral horn and get another octave of LF extension. "Curves look pretty but below 200 Hz they really don't do anything.".....whatever..." Subs built to exactly the same design save for using flat versus rounded reflectors show no significant difference in response below 200Hz. Wavelengths in excess of five feet don't need 'assistance' in negotiating the bends of a horn. All smooth curves and constant flare rates makes for very nice advertising copy but they have no sonic benefit in subs. Totally different story in midbasses, though. |
Posted By: Contour
Date Posted: 26 February 2006 at 10:58am
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Hello Jones, Very strange, every time I read a post by you it reminds me of a Bill Fitzmaurice post. Same use of language and so on. But I assume you are not the same person. Best regards, Walt |
Posted By: Phil B
Date Posted: 26 February 2006 at 11:22am
I was thinking the same..? And I`d love the math on the rough versus smooth..not saying your right or wrong ...proof please.. .p. ------------- Mostly harmless.... except if catering is shut. Solar Sound System Shennanigans.. http://diyhifi.biz/" rel="nofollow - http://diyhifi.biz/ |
Posted By: tb_mike
Date Posted: 26 February 2006 at 5:47pm
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Bill fitz talker or not,the fact is true. see JLH audio measurement on smooth vs 45* reflector corners. Hes posted alot on audioasylum regarding this.
consider a 8metre long 40hz wave,with a 1/4wavelength of 2metres. Just as a elephant stands on an ant,an 8metre long wave doesnt care if the curve is flared or not. |
Posted By: minaximal
Date Posted: 26 February 2006 at 7:52pm
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what about fluid dynamics. thats precisely why the geiger spreadsheet compensates for acoustic flow around smooth folds. also most folded bass horns have well over 90* bends without reflectors, and play up to 100hz which is 3.4m or 85cm 1/4 wavelength which could possibly be modulated by a 42.5cm pathlength variation 1/8th wavelength, quite conceivable with larger cabinets. |
Posted By: LostGrayCat
Date Posted: 26 February 2006 at 9:14pm
Think I've seen this design somewhere  just for a different kind of bottom end
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Posted By: djstefanos
Date Posted: 26 February 2006 at 10:22pm
 no offence, looks like a toilet
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Posted By: mykey
Date Posted: 26 February 2006 at 11:07pm
 just spat my coffee out ------------- ......just all them hanging there like giant bananas. |
Posted By: tb_mike
Date Posted: 27 February 2006 at 5:45am
Yes it certainly does. The question is it audible? Does a nicely folded horn that one has taken all this effort to fold so well,actually operate any higher? 42cm pathlength variation,i dont see how that would occur in a typical S or spiral basshorn. Cheers. |
Posted By: Joe Jones
Date Posted: 27 February 2006 at 8:04am
The comparison is most flattering, thank you, but alas I am not he. I'm Batman. |
Posted By: minaximal
Date Posted: 01 March 2006 at 9:16am
exactly, and with accumulated compromises with horn design, its best to try and minimise these, so theres no harm in trying. although i dont see how it will help much in a scoop for upper band frequency response due to the pathlength differences from the direct radiating element and rear horn loaded. (42cm you say eh!?) the modulation thing was from the bass modulating the upper freqs of divisable wavelength, but i cant remember where i read it.. its not my thing, but as mykey insinuates; people who like scoops will probably like the "dirtyness" of the sound this would produce. howd it go mykey? |
Posted By: mykey
Date Posted: 01 March 2006 at 11:16pm
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should be finished this week, ill let you know. and if it doesnt work??? does anyone want to by a smooth curved wheel barrow? ------------- ......just all them hanging there like giant bananas. |
Posted By: Centauri
Date Posted: 04 March 2006 at 9:57am
| Well, if it doesn't work, it might still be usable by lining the curves with sound deadening material - this might reduce the transmission of higher frequencies through the horn path. Could be worth a try rather than relegation to firewood.. |
Posted By: mykey
Date Posted: 16 March 2006 at 4:47am
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tighter than a chinese virgin as fast as an Aston Martin as low as a tramp sitting on a park bench in the rain ------------- ......just all them hanging there like giant bananas. |
Posted By: minaximal
Date Posted: 16 March 2006 at 5:10pm
i dont know how tight a chinese virgin is, but i did go out with a japanese ex geisha for a while, as to the rest, technical stuff then!? hows the 100hz region? |
Posted By: mykey
Date Posted: 18 March 2006 at 1:00am
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when played at full range, the mid is quite exceptional (effortless) though some one did mention that would happen? all it needs is a tweeter above. ill put some pics up soon at the moment the cab width is 580mm im increasing it to 610mm. ------------- ......just all them hanging there like giant bananas. |
Posted By: Mark James
Date Posted: 18 March 2006 at 6:42am
i like the way your thinking mykey! |
Posted By: Mark James
Date Posted: 18 March 2006 at 6:45am
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i thought that was what he meant with for a different kind of bottom |
Posted By: Mark James
Date Posted: 18 March 2006 at 6:51am
scoop with a tweeter on top. actualy alot of bass guitarists [ok a particular group but a reasonably sizeable one] with particular playing styles would bite your arm of for such things. i think scoops have got a fair few more uses than peeople like to admit! |
Posted By: mykey
Date Posted: 20 March 2006 at 4:17am
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some build pic's inside the throat.. http://img210.imageshack.us/my.php?image=m17hs.jpg"> and the scoop. Notice that it has no brace at the mo
------------- ......just all them hanging there like giant bananas. |
http://img70.imageshack.us/my.php?image=m35sd.jpg">
http://img83.imageshack.us/my.php?image=dscf04117ky.jpg">
http://img83.imageshack.us/my.php?image=dscf04120dn.jpg">Posted By: Tom Umney
Date Posted: 27 March 2006 at 3:21pm
What driver is that in there? Looks like JBL or P.audio. 
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Posted By: Jay Lawless
Date Posted: 28 March 2006 at 2:30am
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looks more like a JBL...
------------- Previously known as NeverWinter Background: Automotive, Live and Home Custom Design. mid/high level based design and feild experience. Bass specialist |
Posted By: Tom Umney
Date Posted: 28 March 2006 at 4:03pm
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P.audio however make JBL clones/copies that look very alike JBL.
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Posted By: Jake_Fielder
Date Posted: 21 December 2007 at 12:34pm
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I know this was years ago but did you only ever make one? or did you make several??
It looks nice, was it hard to build?
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Posted By: Roland
Date Posted: 28 December 2007 at 8:17am
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i thought that P-Audio make for JBL cones and magnetics ..............
I heard also that P-Audio have membrame's for EV and JBL .........
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Posted By: tweeter box
Date Posted: 26 June 2008 at 8:28pm
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Looks good Myk how did it sound 40 - 100 hz? ------------- PRECISION SOUND SYSTEM. Feeding the peoples needs for Roots Music. Strictly premium grade reggae and dub steppers from the early 70's to present day. |
Posted By: Deadbeat
Date Posted: 26 June 2008 at 9:16pm
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I bet Count Basie would sound lovely through that.
------------- Away on extended leave. |
Posted By: mykey
Date Posted: 27 June 2008 at 4:28am
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It was something I shouldn't have done tweet.......made all the straight panels curved
it cleaned it up too much they would be superb above some original sccops or big bertha's doing the same as the GSA rig, I would imagine they sound cleaner than the GSA rig ------------- ......just all them hanging there like giant bananas. |
Posted By: mykey
Date Posted: 27 June 2008 at 4:36am
http://img210.imageshack.us/my.php?image=m17hs.jpg"> http://img83.imageshack.us/my.php?image=dscf04120dn.jpg">
notice the curved scoop, each part is 18mm thick and cnc'd into a curve  and the depth is very thick, none of your 1/8th ply sh*te, kick that, you'll lose a knee------------- ......just all them hanging there like giant bananas. |