STEvil Posted May 3, 2010 Report Share Posted May 3, 2010 This part of driver tech i'm a little weak on. My two basic questions are what would happen if the pole piece was removed from the structure (not questioning cooling) and what effect do different coil placements have? IE: If the coil was completely out of the gap at rest, completely centered in the gap at rest, or 1/2 entered into the gap at rest? I can pretty much easily assume that if the coil is too far from the gap it will produce very little magnetic force.. but how far is too far? Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
STEvil Posted May 4, 2010 Author Report Share Posted May 4, 2010 bump time Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
bassl0va Posted May 4, 2010 Report Share Posted May 4, 2010 This part of driver tech i'm a little weak on. My two basic questions are what would happen if the pole piece was removed from the structure (not questioning cooling) and what effect do different coil placements have? IE: If the coil was completely out of the gap at rest, completely centered in the gap at rest, or 1/2 entered into the gap at rest? I can pretty much easily assume that if the coil is too far from the gap it will produce very little magnetic force.. but how far is too far? OK, I'll try my best at explaining. The magnet on a speaker is magnetized vertically, so that the top is the north (I think) pole, and the bottom is the south. The top plate is attached to the top of the magnet, causing it to act as an extension of the northern pole. And the pole piece, because it is attached to the back plate, will act as an extension of the southern pole. So I assume that removing the pole piece would either cause the speaker to sound like crap, or maybe barely function. The coil question is linked to the pole piece question in someway. In a very good speaker (lets say DD) the coil will have exactly the same amount of coil on either side of the gap. Now, lets say the coil is 2.5"s long, and the gap (the thickness of the top plate, pretty much) is 0.5"s. This means the the speaker can move linearly 1" in each direction, it can do more (maybe even double!) but it won't be as linear. To stay perfectly (or as perfect as we can make a speaker, which is pretty damn shocking) linear, the gap must have its full length, 0.5"in our example, full with coil. Now, take the coil just out of the gap, not only will it sound shocking, the closest to linear it will get is at the bottom of its down stroke. With this placement, our example DD would have to be moving a total of 1" just for the gap to be full at the bottom of the stroke, up this to 2"s of excursion and the bottom 0.5"s will be the only part that is linear. So unless the coil is completely centered (1" either side of the gap with our example DD) it will behave very badly and have very bad sounding and quiet output. If the spider has sagged 0.25" you will probably not ,realistically, notice a difference, but if it is as bad as your first or third examples, it will suck. As for how far is too far. I'm sure you could get some vibration with the coil 12"s away from the gap. The magnets are quite strong, go round to grannies and sit your DD lvl5 on the table and I'm sure she will be asking WTF is happening with the picture on her 20 year old tv (which is 6-10ft away from the table). Quote My RE MT 18" wall build Former build, farewell beloved wall.In progress, Toyota Starlet build This forum has a massive boner for ridiculous electrical upgrades. Link to comment Share on other sites More sharing options...
STEvil Posted May 4, 2010 Author Report Share Posted May 4, 2010 http://www.europe-audio.com/Product.asp?Product_ID=5629 http://www.codrive.com/basstr.htm http://www.audiojunkies.com/blog/1201/adire-audio-parthenon-revisiting-the-ultimate-subwoofer hmm... I wonder Anyone else got examples of split motor and similar designs? Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
Mr. Darkjustice Posted May 4, 2010 Report Share Posted May 4, 2010 http://www.europe-audio.com/Product.asp?Product_ID=5629 http://www.codrive.com/basstr.htm http://www.audiojunkies.com/blog/1201/adire-audio-parthenon-revisiting-the-ultimate-subwoofer hmm... I wonder Anyone else got examples of split motor and similar designs? looks like a sex toy. Quote Fusion With A Stetsom 4k2d on 2 DC XL 15s tuned to 31hz and Subs and ports forward The Revolution Was Not Televised But There Is This Thread(clicky) Dr Merkenstein is my 360 gamertag and my profession. When shit gets real, call in the Doc Link to comment Share on other sites More sharing options...
bassl0va Posted May 4, 2010 Report Share Posted May 4, 2010 (edited) http://www.europe-audio.com/Product.asp?Product_ID=5629 http://www.codrive.com/basstr.htm http://www.audiojunkies.com/blog/1201/adire-audio-parthenon-revisiting-the-ultimate-subwoofer < the video on this page is just wrong hmm... I wonder Anyone else got examples of split motor and similar designs? ^ P audio used to make subs like that, from 6.5-15". I was going to get one but they said they no longer sold them Those other ones are quite interesting though, independent research FTW! Edited May 4, 2010 by bassl0va Quote My RE MT 18" wall build Former build, farewell beloved wall.In progress, Toyota Starlet build This forum has a massive boner for ridiculous electrical upgrades. Link to comment Share on other sites More sharing options...
STEvil Posted May 5, 2010 Author Report Share Posted May 5, 2010 EXO's got a video with a split-coil sub in it.. best subs ever video or something. I cant track down what make it is Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
STEvil Posted May 7, 2010 Author Report Share Posted May 7, 2010 bump for moar! Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
STEvil Posted May 11, 2010 Author Report Share Posted May 11, 2010 man, gotta bump this again? Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
Forevrbumpn Posted May 11, 2010 Report Share Posted May 11, 2010 I have experience with the CoDrives, and a subwoofer built LIKE that Raptor The raptor design, at least how we did it was use a spider behind the back plate that was attached to the coil by a aluminum rod that connects to the coil under the dome What this helped with was by using 2 super soft spiders, and a very tight gap coil/motor design , with the spiders mirror imaged to keep the coil as aligned as possible with no possibility of rubbing due to coil rocking side to side, and as linear as possible its more along sound quality The CoDrive, is the best subwoofer ever built in my opinion, I have promoted this woofer to many many people over the years we helped Ron a little, and he helped us. The woofer MOTOR itself is very adjustable, in fact its really is adjustable, you can twist the motor, and adjust excursion to compensate for xmax, Qts, Fs They get loud, they are musical, and just such a awesome trophy piece best subwoofer hands down Quote I have a ritual called "terminator". I crouch in the shower in the "naked terminator" pose. With eyes closed I crouch for a minute and visualize either Arnie or the guy from the 2nd movie. I then start to hum the T2 theme. Slowly I rise to a standing position and open my eyes. It helps me get through my day. The only problem is if the shower curtain sticks to my terminator leg. It sorta ruins the fantasy. Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.