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Old 10th December 2012, 05:48 AM   #541
xrk971 is offline xrk971  United States
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Klampy,
That is a pretty cool and innovative design. I have never seen anything like it. You have drivers facing out now so you should get some highs coming out for stereo separation. Was the main reason one set of drivers face into the box due to lack of space? Have you fired it up yet and how does it sound? Very nice work
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Old 10th December 2012, 05:52 AM   #542
xrk971 is offline xrk971  United States
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Quote:
Originally Posted by Don Hills View Post
Read all of this thread:
Akabak Simulator

Note my "AkAbak for the cognitively challenged" posts.
Go here for the software: R&D-Team - Software Development
Don,
Thanks for the link to the thread and download location.
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Old 10th December 2012, 06:04 AM   #543
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Thanks guys. Badman, it must have been unintentional because im.not sure what you mean by force cancelling. could you help me understand what that means please?

Xrk, thankyou. Yes its running atm but no lid on. It doesnt seem as loud as my first one buts i can already tell it has much more bass. Definately the reason for reversed drivers was packaging restrictions and i definately have a stereo image now. I should have used the smaller drivers in this horn coz infeel the bigger ones are less sensitive/more powerful and might need more than 3w to drive them properly.
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Old 10th December 2012, 06:06 AM   #544
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Is 3w the most ill get off a usb power source? Ie:5v
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Old 10th December 2012, 06:16 AM   #545
xrk971 is offline xrk971  United States
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Quote:
Originally Posted by klampykixx View Post
Is 3w the most ill get off a usb power source? Ie:5v
Klampy,
Give your drivers the juice they need, 3 Watts is so underpowered. My cheap desktop pc speakers are circa 3W - and not very loud. Why don't you get a Lepai T-amp($20) they are 20 W into 4 ohms and sound great - very low distortion and run cool. You can probably remove it from its chassis and fit it inside your box. Although you did it due to volume constraints, I think the fact that one driver faces in and another out allows the asymmetry of the drivers (movement out vs in being unequal) to self-cancel (kind of like common mode rejection). This type of back-to-front technique is used in many other fields to null-distortion: optics sometimes uses two identical lenses - the famous Gauss lens design, complementary transistor pairs, matched dual photodiodes, the list goes on.... Anyhow, you may be on to something pretty cool here.
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Old 10th December 2012, 06:52 AM   #546
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Theyre running on 2x100w at the moment and still arent maxxing out.... :/ lol they are 50w drivers so it kinda figures...

Just put a cd on and straight off the cd player theyre much louder than the laptop can push via the same amp.

Now that there is a little stuffing inside and the lid is sealed they do have that deep punch ive been looking for so the do sound very warm. Not a heap of highs tho so could easily have been accompanied by a tweeter. They do sound clean tho so overall i have achieved ky goal of portable bass so ive got a win there.

Regarding the reversed driver its also wired reverse polarity so theres no cancellation. I forgot initially to reverse it and it sounded bad. but my first thought was that my ss15 subs have the magnet out and they sound epic. It was mostly so i could fit as much speaker in as possible and still give plenty of horn space. I actually had space leftover lol. But it had no positive effect on the sims to make the horn any longer than it already is.

I must say Infected Mushroom: Army of mushrooms. Sounds pretty good on my new speaker box
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Old 10th December 2012, 01:14 PM   #547
xrk971 is offline xrk971  United States
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Sounds like you have a winner there. I expected the drivers to be wired one in reverse otherwise it would cancel amplitude. I am talking about cancelling driver-inherent distortion due to unequal movements on in stroke vs out stroke. Nicely done - do you have some pics or an mp3 from a mic what it sounds like?
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Old 10th December 2012, 03:42 PM   #548
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By having the drivers pushing against a joined panel the way they are, there's a small amount of force-cancellation- the drivers push against each other somewhat, rather than the box, thus equal but opposite forces tend to cancel.

You need a top on that- the horn won't work without a top, and the bass will all cancel as it short-circuits in the free-air above the drivers.
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Old 10th December 2012, 04:44 PM   #549
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I'd like to bring the discussion back to the design of the cornucopya. On page 3 of the patent in paragraph 0021 it describes the cone (5) from Fig. 1 roughly as an outward deflector of the sound waves. Perhaps that's actually important. I wonder if we could add the cone to the simulation model?
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Old 10th December 2012, 04:45 PM   #550
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Looks great Klampy. Glad to hear it sounds good.
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