Speakerplans.com Homepage
Forum Home Forum Home > Plans > New Projects Forum
  New Posts New Posts RSS Feed - Folded horn low mid
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Folded horn low mid

 Post Reply Post Reply Page  12>
Author
Message
doober View Drop Down
Young Croc
Young Croc
Avatar

Joined: 03 January 2006
Location: Cornwall UK
Status: Offline
Points: 1118
Post Options Post Options   Thanks (0) Thanks(0)   Quote doober Quote  Post ReplyReply Direct Link To This Post Topic: Folded horn low mid
    Posted: 05 July 2010 at 8:31pm
Here's my latest attempt at filling the gap between punishers and a 6" mid horn. It's a 10" driver on a horn, folded to make it fit in a sensible sized box.



This shot before I put the side on, also missing the reflector in the bottom left corner.



This one shows the driver chamber and baffle and the general box layout.

I've had a brief listen and it sounds quite good so far. The cutoff isn't as low as hornresp predicted, but it should be usable to around 100/110 hz. The upper end sounds okay, a bit of an ear splitting resonance if I play it too high, somewhere around 500hz. The 6" horn which will go above this can go as low as 300hz, so ther will be room for experimenting with crossover points to get the best sound and balance between bands.

Unfortunately I rushed the build a bit and forget to get many photos, but I'll see if I can find some more.

Kieran


Blahblahblah
Back to Top
biotec View Drop Down
Old Croc
Old Croc


Joined: 07 June 2004
Location: United Kingdom
Status: Offline
Points: 2932
Post Options Post Options   Thanks (0) Thanks(0)   Quote biotec Quote  Post ReplyReply Direct Link To This Post Posted: 05 July 2010 at 9:26pm
another great looking build kieran. What made you carry on experimenting? The last horn that folded back on itself looked very promising I thought; perhaps it was just too much work to reproduce?

Are you going to shape the rear of the bung? I ended up leaving the one in my upper bass cabs flat and it doesn;t seem to make much difference below 300hz. When I ran them up to 500 it started sounding strange and I think that it may be a result of a standing wave hitting the rear of the bung, bouncing back through the cone, and reflecting off the hatch. It may not be an issue with your box though because the back of the bung doesn't have to be parallel to a panel in he chamber.

Good work!
me so horny, me love you long throw.
Back to Top
Saul View Drop Down
Old Croc
Old Croc


Joined: 15 June 2007
Status: Offline
Points: 5912
Post Options Post Options   Thanks (0) Thanks(0)   Quote Saul Quote  Post ReplyReply Direct Link To This Post Posted: 05 July 2010 at 9:54pm
looks very interesting

i have been prototyping a similar loading config with a 15" - i'll try get some pics up over the next few days. 

what driver are you using?
Back to Top
doober View Drop Down
Young Croc
Young Croc
Avatar

Joined: 03 January 2006
Location: Cornwall UK
Status: Offline
Points: 1118
Post Options Post Options   Thanks (0) Thanks(0)   Quote doober Quote  Post ReplyReply Direct Link To This Post Posted: 05 July 2010 at 10:06pm
I've still got the mk1 dooberhoorn mutant w-bin thing. This latest attempt is much easier to build, it has only about one third of the components. I built this one surprisingly quickly thanks to sketchup and the deepss boys with their workshop full of scary woodwork machines.

The new version is also significantly smaller than the original, with a corresponding reduction in low frequency output, but I never needed the 80hz capability of the original.

Regarding the bung, a front chamber of 2 litres should allow the horn to reach above 400hz. I've not measured the cone volume but it must be significantly less than 2 litres. I see your point about the reflections though, and even though I have a small rear chamber (4 litres net) the rear panel is parallel to the baffle. I may try adding a shallow cone to the face of the bung to see if it makes any difference. I don't know if it is advantageous to deliberately restrict the upper end, would a restricted bandwidth help the efficiency in band?

The driver is an old Zomax cast chassis thing with a huge magnet. I've got four of them gathering dust. When I decide which horn to use I will try some more exotic drivers, the 18sound 10MB600 looks tempting.

Kieran


Blahblahblah
Back to Top
cravings View Drop Down
Old Croc
Old Croc
Avatar

Joined: 30 January 2007
Location: Ireland
Status: Offline
Points: 7441
Post Options Post Options   Thanks (0) Thanks(0)   Quote cravings Quote  Post ReplyReply Direct Link To This Post Posted: 06 July 2010 at 1:41am
i love the work you put into these doober. looks great
Back to Top
doober View Drop Down
Young Croc
Young Croc
Avatar

Joined: 03 January 2006
Location: Cornwall UK
Status: Offline
Points: 1118
Post Options Post Options   Thanks (0) Thanks(0)   Quote doober Quote  Post ReplyReply Direct Link To This Post Posted: 06 July 2010 at 5:02pm
Here's a pic of the complete box (of sorts)



There's still some work to be done, mainly on the 1" horn, space is a little tight and there isn't room to fit the compression driver in, it fouls the rear chamber of the 10" section. I either need some cunning grp back bowl for the 10", or to make a new hf horn 25mm shorter.

A quick listen with guessed at lms settings and no delays sounded very promising, the three sources blend together very well, it's almost like all the sound is coming from the hf horn.

Box size is 500mm wide (230mm at the rear), 700mm tall, 610mm deep. Weight is 38kg. I also need to look at where I can put some handles, any suggestions?

Kieran
Blahblahblah
Back to Top
doober View Drop Down
Young Croc
Young Croc
Avatar

Joined: 03 January 2006
Location: Cornwall UK
Status: Offline
Points: 1118
Post Options Post Options   Thanks (0) Thanks(0)   Quote doober Quote  Post ReplyReply Direct Link To This Post Posted: 06 July 2010 at 5:16pm
I did some plots of the 10" section in less than ideal conditions. It's rather windy here today (as usual), so I did some plots in a sheltered corner of the garden with the box on the floor. As usual these plots are not calibrated for SPL, and are just to get a rough idea of the response.

This was done with the mic resting on the floor, capsule just inside the mouth



This one is with the mic on the ground approx 1200mm from the front of the cab



I need to do some more measurements at a distance from the cab, but won't have access to a field (or a calm day!) for a while.

I also need to do a phase plot, but I'm having problems getting the right delay to reduce the 'wrapping', my plots always look like a saw blade.

Kieran


Blahblahblah
Back to Top
Ibex View Drop Down
Young Croc
Young Croc


Joined: 27 May 2009
Status: Offline
Points: 1013
Post Options Post Options   Thanks (0) Thanks(0)   Quote Ibex Quote  Post ReplyReply Direct Link To This Post Posted: 06 July 2010 at 5:52pm
nice mid horn, especially the phase plug, great job! Thumbs Up
for which driver did you engineer the 15" trap and the 10" mid horn?
Back to Top
Wrek0ne View Drop Down
Young Croc
Young Croc


Joined: 10 February 2011
Location: Cambridge
Status: Offline
Points: 749
Post Options Post Options   Thanks (0) Thanks(0)   Quote Wrek0ne Quote  Post ReplyReply Direct Link To This Post Posted: 19 February 2011 at 2:16pm
these look absurd.... amazing build 
Poll this!
Back to Top
discosucks View Drop Down
Old Croc
Old Croc


Joined: 06 November 2009
Status: Offline
Points: 1548
Post Options Post Options   Thanks (0) Thanks(0)   Quote discosucks Quote  Post ReplyReply Direct Link To This Post Posted: 25 December 2012 at 10:26pm
This is amazing !! 
Back to Top
discosucks View Drop Down
Old Croc
Old Croc


Joined: 06 November 2009
Status: Offline
Points: 1548
Post Options Post Options   Thanks (0) Thanks(0)   Quote discosucks Quote  Post ReplyReply Direct Link To This Post Posted: 25 December 2012 at 11:13pm
Are plans for boxes like these available to joe's like myself??

And if not can someone like me with little understanding of folded stuff / phase plugs 
learn to design his own box? 

This project really excites me!!!! 
Back to Top
doober View Drop Down
Young Croc
Young Croc
Avatar

Joined: 03 January 2006
Location: Cornwall UK
Status: Offline
Points: 1118
Post Options Post Options   Thanks (0) Thanks(0)   Quote doober Quote  Post ReplyReply Direct Link To This Post Posted: 27 December 2012 at 8:33pm
I don't have any detailed plans for this box, I worked out a lot of the dimensions as I built it.

I think anyone can design their own box with enough time and commitment.
Blahblahblah
Back to Top
 Post Reply Post Reply Page  12>

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 0.219 seconds.