Open Baffle Epiphany!
- Thread starter cptnCanada
- Start date
BHamm
The pendulum swings.
Also, you can google "circle hole jig" and get many ideas on making your own. Not too hard. I bought mine before I learned how easy it can be to make my own.
TubeHiFiNut
Super Member
Yes, running the Alphas in parallel.
I plan to biamp and will dial in the low pass frequency and level with a Dahlquist DQ-LP1.
Poultrygeist
Lunatic Member
Porkloin
Oscar Heil Groupie
Circle Jig
Hey, I noticed that your router didn't look like a plunge router. How did it work with the jig?
Hey, I noticed that your router didn't look like a plunge router. How did it work with the jig?
BHamm
The pendulum swings.
Well, not the best. It's borrowed from a friend and fellow AKer, Duff so I'm not complaining. I tried to make the initial plunge as even and level as possible to avoid an angled cut. I was able to fill and sand any little imperfections. I'm shopping for my own plunge router now.
Poultrygeist
Lunatic Member
Many plunge routers are compatible with the screw holes on a Jasper jig but there are some that won't fit. I went with a Craftsman 1 3/4 hp single speed as I knew it was a good fit. It's fairly light weight which makes it easy to handle compared to some of the heavy weight routers.
You can pick up the Jasper's at Parts Express or even a Woodcraft if you have one of those around.
The model I've found to do most for me is the middle sized one...
http://www.parts-express.com/jasper-circle-jig-model-200--365-250
I haven't used it but PE is showing now a model 240 that might be better as it goes smaller...though at a higher price.
The only real problem when you get down under the base of your router for a real small hole is that it's tough to tell what hole your inserting the pivot pin into. A mistake really bits as it's liable to be too late by the time you find out and there goes that wood.... :tears:
The Jaspers are brittle. Use care. A friend knocked his almost new jig on his router off onto the floor and it busted all up. After a lot of holes, I had one bust out around one of the screws through the jig going into the base of the router. It's just a brittle kind of material, so use care to get the most mileage.
I've not seen any plans for anything you could put together yourself that could ever approach the precision of the cuts possible with the Jasper. I confidently do the recess for the outer of a driver, then do the penetration to do the cutout. Sometimes with a wide rim on the basket, several shallow cuts before the main cutout. It's all pretty easy and very precise...as long as you manipulate the numbers correctly.
I always cross check myself by using a compass with pencil to make a circle first. Measure that circle back to my driver as a cross check. And then when I lower the router, eyeball to make sure I'm just inside that line before I start my cut. And yes, I've caught myself a few times with the pivot pin in the wrong hole or something that would have messed it all up if I wouldn't have had the way of double checking myself. Darn me.... :nono:
A quarter inch straight bit is what I usually use. Several cuts to get through the wood...don't try to get too much at a time! And then a round over bit to give the edge a nicer look...
Sometimes it's still a lot of work...even with a good tool... But wood work is always a pleasing work!
EV3
The model I've found to do most for me is the middle sized one...
http://www.parts-express.com/jasper-circle-jig-model-200--365-250
I haven't used it but PE is showing now a model 240 that might be better as it goes smaller...though at a higher price.
The only real problem when you get down under the base of your router for a real small hole is that it's tough to tell what hole your inserting the pivot pin into. A mistake really bits as it's liable to be too late by the time you find out and there goes that wood.... :tears:
The Jaspers are brittle. Use care. A friend knocked his almost new jig on his router off onto the floor and it busted all up. After a lot of holes, I had one bust out around one of the screws through the jig going into the base of the router. It's just a brittle kind of material, so use care to get the most mileage.
I've not seen any plans for anything you could put together yourself that could ever approach the precision of the cuts possible with the Jasper. I confidently do the recess for the outer of a driver, then do the penetration to do the cutout. Sometimes with a wide rim on the basket, several shallow cuts before the main cutout. It's all pretty easy and very precise...as long as you manipulate the numbers correctly.
I always cross check myself by using a compass with pencil to make a circle first. Measure that circle back to my driver as a cross check. And then when I lower the router, eyeball to make sure I'm just inside that line before I start my cut. And yes, I've caught myself a few times with the pivot pin in the wrong hole or something that would have messed it all up if I wouldn't have had the way of double checking myself. Darn me.... :nono:
A quarter inch straight bit is what I usually use. Several cuts to get through the wood...don't try to get too much at a time! And then a round over bit to give the edge a nicer look...
Sometimes it's still a lot of work...even with a good tool... But wood work is always a pleasing work!
EV3
Thank you sir! You learn something on each one you could do better next time or wouldn't do the same again. :yes:
Come to Carverfest in September and I should...hopefully...really have something to show. And listen to!
Woo-Hoo!! Hopin' to really kick all the stops out!! :scratch2:EV3
PR Audio
Super Member
I have a Black & Decker RP-250, which I don't know how to use, but working on it. It fits Jasper's Circle Jigs, though the RP-250 comes with a circle jig, not like Jasper's, but it does the job. For MDF, holes up to 6" diameter, I use an acoustic ceiling hole cutter in a bench drill; it works on MDF up to 1/2" thick. For $60.00 I recommend the RP-250 for it's many features, but some people have had reliability issues with mechanical parts; not me. Not for everyday use.
Poultrygeist
Lunatic Member
good job BHamm :thmbsp:
Another candidate for low frequency crossover or augmenting purposes that you might run into from time to time, is the Sumo Delilah. The Delilah has 5 positions available from 50 to 125hz so it's only a candidate if you're looking for that cross or augment down low. But it is a nice unit if that'll fit what you're doing.
Here is one currently floating through eBay. No affiliation...
http://www.ebay.com/itm/SUMO-DELILAH-/131485849134?pt=LH_DefaultDomain_0&hash=item1e9d2ad62e
Here is a review Stereophile published about the Delilah and it's original companion woof, the Samson.
http://www.stereophile.com/content/sumo-samson-subwoofer-amp-delilah-crossover
If your OB design uses a larger main driver...and/or you run levels conservative enough, you may get way with not having the filter elements of crossover in front of that main and you might be able to get away with only an augmenting lower driver. If you are careful with level and listen for the hardening sound of distortion from louder elements, then the lack of the phase shift of no rolloff being involved may...maybe outway the added movement of the cone trying to do the lower frequencies that are rolled off due to the wrap around cancellation. Use care and decide for yourself and your ears before you automatically use both the high pass and low pass of a crossover like this.
EV3
Here is one currently floating through eBay. No affiliation...
http://www.ebay.com/itm/SUMO-DELILAH-/131485849134?pt=LH_DefaultDomain_0&hash=item1e9d2ad62e
Here is a review Stereophile published about the Delilah and it's original companion woof, the Samson.
http://www.stereophile.com/content/sumo-samson-subwoofer-amp-delilah-crossover
If your OB design uses a larger main driver...and/or you run levels conservative enough, you may get way with not having the filter elements of crossover in front of that main and you might be able to get away with only an augmenting lower driver. If you are careful with level and listen for the hardening sound of distortion from louder elements, then the lack of the phase shift of no rolloff being involved may...maybe outway the added movement of the cone trying to do the lower frequencies that are rolled off due to the wrap around cancellation. Use care and decide for yourself and your ears before you automatically use both the high pass and low pass of a crossover like this.
EV3
darg
When in doubt, C4
This looks like a pretty flat angle but I would assume that is due to their lower size and you need to have them pointing upwards more than when they would be taller?
PR Audio
Super Member
FINALLY!!!! Finished my Hybrid OB Bookshelfs!!!
darg
When in doubt, C4
Any progress on yours?
I w working the last couple of days on the crossover. The 4-way I have is a monster from the early 90ies from visaton and somehow they have crazy circuit in there that partially mixes the high pass for the mid/bass with the inductor for the low pass of the bass. Waiting to get a schematic from visaton for this thing but I think I figured what they did and opened up the lower end of the of the mid/bass to run down into the full bass to have the magnavox and the eminence in parallel in the deep bass but cut off the magnavox at 300hz. This gives me finally more at the deep end, the right choice.
I also tackled partially the screaming/squeaky mid horn with a proper l-pad of roughly -3dB.
Not sure if it is the horn itself or the using a horn in general but I have now a nicer level equalization for the mid range but sometimes the horn is a little nerve killing over time. Seems like some resonances are strong but not all the time. I'm testing with more vocal accustic music and some singer are like they have either a lisp or other speech imparments
Adele and Agnes Obel sound great but George Ezra has a problem with is "treasure chest".