3 way MTMB

[CCU]

Hi i'm thinking about making a pair of new speakers and i was wondering if the units that i've looked at would be a good fit for each other.

tweeter: Vifa XT25BG60-04
Link

Bass: Peerless XXLS 830847
Link

Midrange: Peerless HDS 830875
Link

i also considered the little brother of the midrange unit, but discarded the idea because of lower effiency

I were thinking of making the crossover point at 300/2500hz

does anyone know a reason why this would't work well together?

Best regards

[infinia]

Hi
Very good driver choices for your crossover targets.

1) The vifa tweeter should be better at the 8 ohm version instead?
2) Woofer is a DVC in parallel at 3 ohm, s/b easier to implement BSC designs. Should be fine using high current amplifiers. If you are using bass reflex the port will be around 45 cm long.
http://www.tymphany.com/830847-app-note

3) Excellent 8 ohm midrange. Easier to cross at 2,5K than the phase plugged version. Not as good at LF distortion, but less an issue here if crossed at 300Hz.

edit> oops just realized you have 2 mids for MTM, so use 4 ohm all around then. Now a MTM wants at least a 3rd order response at a freq probably lower than your than your target. Xover to the tweeter at a freq. related to the spacing of the mids.

[Andy G]

a 12" xxls used to 300Hz ???

[crazyhub]

Originally posted by Andy G
a 12" xxls used to 300Hz ???

Piston range up to 450Hz so why not?

[Moondog55]

i would have used a sealed box and this woofer
http://www.tymphany.com/830669
if it was Me/ but I have no personal experience with these particular drivers, I just looked at the break-up peaks and dips and thought that 120Hz tops for the XXLS



A pair of these would however need a bigger box than 1 X ported

[Andy G]

there is way more to it than piston range.. the main issue is what it will sound like !!

If he thinks he can make an XXLS sound decent up to 300Hz.....OK.

Its just not something I would attempt.

[crazyhub]

Originally posted by Andy G
there is way more to it than piston range..

Way more what? Please say us the technical reasons you think so, thank you.

[infinia]

Originally posted by infinia

oops just realized you have 2 mids for MTM, so use 4 ohm all around then. Now a MTM wants at least a 3rd order response at a freq probably lower than your than your target. Xover to the tweeter at a freq. related to the spacing of the mids.

I think 3rd order filters at 1.8~2.0KHz with closest spacing between mids would be advised. Then your tweeter might not like that tho

see D'Appolito MTM http://www.parts-express.com/project...project=USHERs


search http://www.google.com/search?hl=en&q...earch&aq=f&oq=

[CCU]

Originally posted by Andy G
there is way more to it than piston range.. the main issue is what it will sound like !!

If he thinks he can make an XXLS sound decent up to 300Hz.....OK.

Its just not something I would attempt.

well the crossover point could go down to 100hz, the midrange drivers could easily go that far down, but then i might have to make that box a basreflex also

[CCU]

Originally posted by Moondog55
i would have used a sealed box and this woofer
http://www.tymphany.com/830669
if it was Me/ but I have no personal experience with these particular drivers, I just looked at the break-up peaks and dips and thought that 120Hz tops for the XXLS



A pair of these would however need a bigger box than 1 X ported

that would make the box to big