Speakerplans.com Homepage
Forum Home Forum Home > Plans > Scoops
  New Posts New Posts RSS Feed - what is a scoop anyway???
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

what is a scoop anyway???

 Post Reply Post Reply Page  <123>
Author
Message
moray james View Drop Down
Registered User
Registered User


Joined: 07 September 2005
Location: Canada
Status: Offline
Points: 141
Post Options Post Options   Thanks (0) Thanks(0)   Quote moray james Quote  Post ReplyReply Direct Link To This Post Posted: 21 December 2006 at 11:44am
Also have a look at this scoop horn http://www.audioheritage.org/vbulletin/showthread.php?t=3765&page=3&highlight=scoop+horn see thread number33. I tried to post this picture but could not make it work so you will have to follow the ling to the Lansing Heritage site. This is a great site to bookmark if you have not already. Regards Moray James.
moray james
Back to Top
jethrocker View Drop Down
Old Croc
Old Croc


Joined: 07 June 2006
Location: Chiapas, Mexico
Status: Offline
Points: 1942
Post Options Post Options   Thanks (0) Thanks(0)   Quote jethrocker Quote  Post ReplyReply Direct Link To This Post Posted: 21 December 2006 at 1:20pm
James, will try to get a sketch up when I can.. if you can picture it it was pretty much the same thing, but with an extra fold moving the throat aperture to the top of the baffle behind the cone. Would need some fiddling to get throat area right, and I'm not sure of the effect of the driver firing more directly into the throat, rather than at a baffle-you never know, could mean more punch or better loading?
Back to Top
moray james View Drop Down
Registered User
Registered User


Joined: 07 September 2005
Location: Canada
Status: Offline
Points: 141
Post Options Post Options   Thanks (0) Thanks(0)   Quote moray james Quote  Post ReplyReply Direct Link To This Post Posted: 21 December 2006 at 5:50pm
Do have a look at how the throat and back cavity are treated in the AJ horn above. I get the impression that Rog would approve. Seems to me that Rog used to have a little lip just at the throat of his big horn cabs and now the posted designs do not show it. Kind of like the little lip in the HD designs. For all I know they are important annd help a lot and Rog has simply removed them from his posted designs to keep an edge. I have seen this exact treatment in other horns like the AJ above. Perhaps Rog will comment or someone with modeling skills can run som sims to show the difference this design mod has. Shrinking the throat impacts the banwidth extension up rather than down and effects the load on the driver.  Would love to find some Hi End auto head designers with (interested in audio also) computer modeling to work on throat geometry air flow and evenness of pressure on the cone. Anybody know one of these? Best regards Moray James.
moray james
Back to Top
COWFOOT View Drop Down
Registered User
Registered User


Joined: 26 September 2005
Status: Offline
Points: 1088
Post Options Post Options   Thanks (0) Thanks(0)   Quote COWFOOT Quote  Post ReplyReply Direct Link To This Post Posted: 21 December 2006 at 8:04pm

Suppose one enclosed the driver of a scoop in a sealed chamber with removable cover,what would this do to the response? Would efficiency increase?



Edited by COWFOOT - 21 December 2006 at 8:24pm
Back to Top
jethrocker View Drop Down
Old Croc
Old Croc


Joined: 07 June 2006
Location: Chiapas, Mexico
Status: Offline
Points: 1942
Post Options Post Options   Thanks (0) Thanks(0)   Quote jethrocker Quote  Post ReplyReply Direct Link To This Post Posted: 22 December 2006 at 3:23pm
Cowfoot, effectively, you'd just be turning the scoop into a rear loaded horn. You'd lose the harmonics from the direct radiation, taking away the scoopy sound we love. Not sure but I think you'd gain a bit of efficiency up in the range, rather than extending the low end response. Response should be a bit flatter also ue to more constant loading on the cone?Showing my lack of knowledge now so I'll leave someone else to give you a more educated answer.
 
Your post reminded me of a litttle dayadream I had the other day about building a scoop type box with front loaded driver and creating a sealed chamber in front of the driver out of perspex or similar. Would look nice don't you think?
Back to Top
jethrocker View Drop Down
Old Croc
Old Croc


Joined: 07 June 2006
Location: Chiapas, Mexico
Status: Offline
Points: 1942
Post Options Post Options   Thanks (0) Thanks(0)   Quote jethrocker Quote  Post ReplyReply Direct Link To This Post Posted: 22 December 2006 at 3:33pm
@James, just looked at the AJ horn now. Thats pretty much the sketch I was describing.. I did a few with slightly different angles on baffles etc to see which would make most effective use of space, but that was the general idea, an extra fold and throat at the top of the rear chamber.
 
I think you're on the right lines with the throat, though I'm not sure if it's having the lip thats important (though it could provide some kind of compression effect) or if it's just to get the throat to the required dimensions while keeping the chamber a sensible shape.
 
The AJ design seems to have a very small throat compared to say the superscoop. I guess this is due to the more dated drivers used and their T7S parameters..
 
Apologies for spelling..I'm typing on a keyboard so old the letters that were rewritten in tippex have vanished.
Back to Top
COWFOOT View Drop Down
Registered User
Registered User


Joined: 26 September 2005
Status: Offline
Points: 1088
Post Options Post Options   Thanks (0) Thanks(0)   Quote COWFOOT Quote  Post ReplyReply Direct Link To This Post Posted: 22 December 2006 at 3:50pm
Jethrocker: I like the idea of using Perspex or Plexiglas for the access cover of the sealed chamber.
Back to Top
moray james View Drop Down
Registered User
Registered User


Joined: 07 September 2005
Location: Canada
Status: Offline
Points: 141
Post Options Post Options   Thanks (0) Thanks(0)   Quote moray james Quote  Post ReplyReply Direct Link To This Post Posted: 23 December 2006 at 1:52am
if you look closely at the AJ Horn on the Lansing page you will see that the throat has the small vee shaped lip tight at the edge and also the the throat is closed down on the top edge of the driver as well. Regards Moray James.
moray james
Back to Top
jethrocker View Drop Down
Old Croc
Old Croc


Joined: 07 June 2006
Location: Chiapas, Mexico
Status: Offline
Points: 1942
Post Options Post Options   Thanks (0) Thanks(0)   Quote jethrocker Quote  Post ReplyReply Direct Link To This Post Posted: 30 December 2006 at 10:13pm
James, still got this thread in mind..Just been busy going through the xmas motions. Going to print that AJ plan to have a better think about it.
Back to Top
jethrocker View Drop Down
Old Croc
Old Croc


Joined: 07 June 2006
Location: Chiapas, Mexico
Status: Offline
Points: 1942
Post Options Post Options   Thanks (0) Thanks(0)   Quote jethrocker Quote  Post ReplyReply Direct Link To This Post Posted: 20 January 2007 at 6:07pm
james..haven't seen you around for time-hope all is good your side. I noticed you appeared again the last couple of days. Any more thoughts on this??
 
edit:forum didn't bump up the thread??


Edited by jethrocker - 20 January 2007 at 10:29pm
Back to Top
jethrocker View Drop Down
Old Croc
Old Croc


Joined: 07 June 2006
Location: Chiapas, Mexico
Status: Offline
Points: 1942
Post Options Post Options   Thanks (0) Thanks(0)   Quote jethrocker Quote  Post ReplyReply Direct Link To This Post Posted: 20 January 2007 at 10:30pm
test post.. forums not bumping this up...
 
edit:thats better..


Edited by jethrocker - 20 January 2007 at 10:30pm
Back to Top
moray james View Drop Down
Registered User
Registered User


Joined: 07 September 2005
Location: Canada
Status: Offline
Points: 141
Post Options Post Options   Thanks (0) Thanks(0)   Quote moray james Quote  Post ReplyReply Direct Link To This Post Posted: 21 January 2007 at 5:56am
posted some stuff in "other plans" Regards.
moray james
Back to Top
 Post Reply Post Reply Page  <123>

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2023 Web Wiz Ltd.

This page was generated in 0.094 seconds.