mmmt speaker design first timer

[boosted1023]

I've been toying with the idea of building my own speakers ever since I started upgrading my car sound system 5 years ago. I acquired a bit of cash working over the summer and I've started my project kind of backwards. I already have some of the drivers I want to use. I picked the drivers from a price and hype format(I know its a stupid way to go about it but what's done is done! Those dang reviews can be so convincing) I picked up a pair of Aurasound NSW2-326-8A-120 2" Full Range based on their use in the Linkwitz Pluto's:

https://www.madisound.com/store/product_info.php?manufacturers_id=121&products_id=8465

And I have a pair of Peerless 835004 SDS 6-1/2" Woofer 4 Ohm based on their cheap price and raving reviews:

Peerless 835004 SDS 6-1/2" Woofer 4 Ohm | Parts-Express.com


I also have PSB Alpha B1's and Mission 701's along with some old KLH and RSL speakers from the 80's and some other bookshelfs from MB Quart and Boston Acoustics that aren't worth listening too.

My plan was to make my own version of the Pluto's that were passive and utilized the Peerless woofer to save money. That idea has recently deteriorated due to my fear of building a crossover and inability to measure/understand t/s parameters.

So now I was thinking of making some type of 3 woofer 1 tweeter (per pair) type monitor with the Peerless woofers and Aurasound tweeters. What I need help/advice with is the design of the crossover and box.

I could just make boxes with out any expertise and use crossovers from my other speakers and I would be willing to bet they would sound decent enough, but I think there are people on here that would like to help me out and get to design my speakers for the pure joy of it!

As far as my experience goes well I can solder decent enough and I've built subwoofer boxes for my car so the woodwork won't be a problem.

I also have a Mac and have failed at using the free online software that is supposed to help with making speakers...

Thanks for reading!

Any input is welcomed and appreciated!

 

[picowallspeaker]

Hi ! Where are the other two M's ??? You said you had 1 pair of woofers!
I would have preferred to buy some 12-16 Ohm versions and parallel them.
Then ,if you have some broken woofers,you can use the cone to make a waveguide
for the little aurasound...opposite to Pluto's design ! It makes easier transition to woofer's
emission and simple 1st order can be used . In fact ,when ordering speakers...crossover parts are as important as the drivers . Both deserve lots of thinking and study .

 

[PeteMcK]

Measurements for those Peerless drivers in this thread
Measurements On A Peerless! - Page 2 - Techtalk at Parts-Express.com

you won’t really get below 50Hz with these, but if that acceptable, a 2.5 way would be the way to go, using one peerless as a mid and the other pair in parallel crossed over at your BSC frequency

 

[boosted1023]

picowallspeaker - what 12-16 ohm woofers would you recommend?

PeteMcK - Is there an alternative driver you have in mind? I was hoping with three 6 1/2" drivers I would get some decent low frequency extension but maybe not.. How can you tell what kind of bass you'll get?

I'm really open to anything guys, as long as its on the cheap side (like $35 a driver). I'd be willing to swap the Peerless drivers before the Aurasound because of their cost.. I appreciate the feedback!

 

[PeteMcK]

re:'How can you tell what kind of bass you'll get?' - type the parameters into unibox:
UniBox - Unified Box Model for Loudspeaker Design - Kristian Ougaard
and play with different box sizes and tunings

 

[boosted1023]

unfortunately the unibox excel doesnt work properly on my mac. maybe its because my version is too new??

Maybe the proper question to ask is what would you do with two peerless woofers and the two aurasound 2inchers?

 

[picowallspeaker]

mmmmh. I would built something like Linkwitz's Pluto..
Just consider the little Aurasound as a FR that needs lots of help in the lows.
Maybe a F.A.S.T. topology with the woofer on a side would make a slim cabinet.
Not going active means that coils >5mH have to be used.
If the woofer permits , also a bandpass enclosure ,i.e. hidden in a double reflex enclosure.

 

[PeteMcK]

try Winisd:
LinearTeam

 

[boosted1023]

take two

Update:

Now I have 4 Dayton RS180's to play with. Does anyone have any input on a MTM with two RS180s and an Aurasound NSW2? I was hoping I could use the Aurasound to cross nice and low..
Could I use a crossover setup like Dr. K's MTM on partsexpress or one of the others similar designs like the Natalie P.?

 

[knifeinthesink]

have you read the Nat p thread. You should. There's alot of good info there. While your at it, read all Jon's posts regarding designs with the RS180.

These xo's are not adaptable. Since you can't measure and don't have experience you should do an existing design. Why not build the Nat Ps. Unlikely you would find better design for the money.

 

[picowallspeaker]

I did it like this : 2 X 6,5" in push-pull in a little BR box and an old paper cone tweeter ,with a waveguide (depth 1" ,throat 2" ,mouth 6.5" :it was a dead woofer indeed ) . Woofers in p-p rolls in frequency more rapidly ,with a "sub behavior ",so they just need a little L to minimize their break-up effects .
The same slope should be accomplished by the tweeter ,and it can ,aided by the wg and a big C . Making that is also a learning path : distance from center-to-center , frequency lengths , slopes and acoustic loads . Check also model Met7 ,on how it's done .

EDIT:just wondering about driver matching ,the little Aura have 84 dB dB/w/m and the woofers are 87 ,which would become when paralleled +3dB for impedance halving and + 3 dB for mutual reinforcement , so not a good match . I did also my calculations wrong ,assuming +6dB from the woofers (truly, due to room gain and to "not a slim box"baffle , some more bass gain is obtained )when there is only one emitting . Otherwise I would have followed Plutos design too ,going active so drivers are independent from each other .