Rs180P/RS28F vs. small DC160 3 way

[filmslayer]

my plan is to revisit my 180P/28F surround in a bigger vented box looking for a lil more extension and i've also been wanting to do a small inexpensive 3 way . i am going to try and build both of these outta the same front slot ported box's using detachable baffles . i will keep the baffle width of my surrounds the same and use the height needed for the 3 way . preliminary box is to be 15"h x 8.5"w x 9"d . the drivers i've selected for the 3 way are
http://www.parts-express.com/dayton-audio-dc160-4-6-1-2-classic-woofer-speaker--295-309
http://www.parts-express.com/famous-maker-3-extended-range-designer-series-driver--299-422
http://www.parts-express.com/peerless-by-tymphany-bc25tg15-04-1-silk-dome-tweeter--264-1040

i am getting my slot port dimensions finalized now and hope to begin cutting wood this weekend . i have everything but the DC160's and the famous maker 3"'s . my modeling i showing just an inductor change and maybe a lil more padding on the 28F that will be done by ear for the 2 way . as for the three way i am all ready seeing some of the challenges that face me , but i think this will be a very fun educational experience for me and give me a good head to head with a decent 2 way and a small inexpensive 3 way ...

more to come , stay tuned ...

[Wolf]

I made a 0.25ft^3 3-way with the DC160S-4 called the Xenolith, and it looks like it suits your size factor.
Just a note in case you need any inspiration,
Wolf

http://techtalk.parts-express.com/forum/tech-talk-forum/63727-extrapolated-theorization-xenoliths

http://s18.photobucket.com/user/wolf_teeth_speaker/library/Xenoliths?sort=3&page=1

[filmslayer]

damn !!! thats a tiny lil 3 way ... i love it !

i'm kinda stuck with my dimensions or at least the width , as i don't wan't to redesign the 2 way XO . i am glad to see that it works ! Josh keeps telling me i'm crazy and my surrounds will sound far better than a small 3 way ...

[Wolf]

I think you'll be just fine with what you want to do. The magnets of the DC160 are really large and control the cone well, especially the shielded models. They have enough drive and sensitivity to work in smaller boxes.

Later,
Wolf

[filmslayer]

i think i got the dimensions all worked out . the 15x8.5x9 gives me .66 ft3 , if i use a 1" x 7" x 20" slot i'll be just under .5 ft3 box tuned to 35 . does anyone see a problem using a slot with those dimensions ?

[jhollander]

I'd bring up the tuning a bit and shorten the port. Unibox show with that tuning you are below flat. My sim at 40 hz tuning gives a F3 of 38. You are at x-max at about 25 watts. With a port area of 21.2 cm, port looks like 1 inch by 3.3 inch by 6.7 inches. Port resonance is at 860 hz.

[filmslayer]

thanks John . what sort of resonance should i be looking for ? for the 3 way its not much of an issue as i'll be crossed way below it but the 2 way crosses at 1850 . is this gonna be a major issue using the same box for both ?

[jhollander]

Port resonance should be above your x-o frequency if possible. Typically you would want to pick a port size based on power at x-max. This would not impact the mid as there's not much output at 860 hz. I would still measure thou.

[filmslayer]

measurements will be taken ! thanks bud . i went to 40htz which shortened my port by 3 inches , but getting the resonance above 1800 is gonna be near impossible . these are the considerations i'm weighing before i cut wood ....

[jhollander]

If you are using the 1 by 7 port expect resonances about 400 hz.

[filmslayer]

not stuck with that . was just thinking that would be the easiest to build and replicate with two different baffles ... my modeling shows 2x2x7 to be about as close for both as i want . no wood is cut rite now !

[filmslayer]

still working on these but hit a couple snags and have some questions ... first , as far as the snags , its freaking HOT down here and outside of work i'm having a hard time finding motivation to go out side and do anything !!!!! on top of that i went to order my drivers ( 160's and 3"ers ) the DC160's are outta stock till 8-11-16 ... gives me more time to play with sims ! as for the questions , was planning on building the box's outta 1/2" MDF . i found at work a very nice hard wood board ( not sure of type ) 9" x 60" , with detachable baffles am i gonna see any issues with this type of combo ? also the plank i found is 9" wide , the 2 way baffles are 8.5" , is that gonna matter all that much ?

[jhollander]

I finished a speaker with braced 1/2 inch MDF and thought It would be better with thicker material. Plus you need something to screw the baffle to so why not double up the 1/2 inch? 1/2 inch on the width would not matter much. With a hardwood baffle over a box, I flush trim the baffle to the box. MDF esp. 1/2 is not very flat over long runs.

[filmslayer]

those were my thoughts exactly john . was planning to use attached 45's in all the corners , i come up with 8 points using hurricane nuts . i've only built with 1/2" stuff one other time and did not like it either ! but the plan is for the 3 ways to replace the Overnight Sensations for my boombox . so weight is the consideration ....

[jhollander]

I skip the t-nuts nuts and go for the pointed wood cap screws.