Mission 753's to 3 way?

[Pjalchemist]

Hi,

I've a set of non Freedom Mission 753's. I have an Arcam Alpha 9 setup and just got a 3rd Power Amp.

My 2 current 9P's are Bi-amped, dual mono. Im thinking of adding a 3rd making it tri-amped and tri mono but each amps to drive the different stages of the Missions.

How easy is it to mod or make the speakers and crossovers do this? Im no sparky, i know a few bits and bobs. I've seen a few diagrams about the cross overs.

Pete

[Pjalchemist]

Anyone got any advice, done it?

[Sonusthree]

I'm wondering if the 753's are 2.5 or 3 way?

[Pjalchemist]

Originally Posted by Sonusthree

I'm wondering if the 753's are 2.5 or 3 way?

2 way as they have 2 sets of inputs and from the wiring crossover scymatyic i've seen!

[ianpengelly]

I believe they are 2.5 way, the bottom two speakers being the bass reinforcement.

There is an illustration of the crossover here:

Mission 753 speaker modding - World-Designs-Forum

[Dr.EM]

It appears 2 of the woofers have a 1st order high-pass network and a 2nd order low-pass network on them. The other 2 appear to have a 3rd order lowpass network with added series resistance.

Not sure exactly what that constitutes though, technically a 3 way as the midrange is effectively running bandpass, but those asymmetrical slopes suggest it is being used as some sort of BSC arrangement.

[Pjalchemist]

Originally Posted by Dr.EM

It appears 2 of the woofers have a 1st order high-pass network and a 2nd order low-pass network on them. The other 2 appear to have a 3rd order lowpass network with added series resistance.

Not sure exactly what that constitutes though, technically a 3 way as the midrange is effectively running bandpass, but those asymmetrical slopes suggest it is being used as some sort of BSC arrangement.

So is possible to split them into 3 different amp inputs?

[Dr.EM]

Looks like you could easily enough

EDIT: See attached

[Loren42]

Originally Posted by Pjalchemist

So is possible to split them into 3 different amp inputs?

Yes, but a standard 3-way active crossover is not going to work. You will need multiple 2-wy crossovers to get the same crossover points and slopes.

Leaving the existing crossovers in place and tri-amping essentially is worthless. The major benefit of tri-amping is getting rid of the passive crossovers so you can directly couple the woofers to the amps. The benefits to doing it this way are too numerous to list here.

[owenhamburg]

I would not agree about it being

Originally Posted by Loren42

essentially is worthless

while I would agree that its better to get

Originally Posted by Loren42

rid of the passive crossovers so you can directly couple the woofers to the amps

their is real benefit to bi-amping and more so than bi-wiring which also shows benefits, even (or maybe especially) with bell wire or cheap speaker cable. All these improvements reduce the woofer's resonances having an effect on the tweeter.

The negative with going active (apart from making/buying an active cross over) is remembering to wire the active crossovers, amps and speakers correctly so you don't send bass to thew tweeter.

I would agree that

Originally Posted by Loren42

The benefits to doing it this way are too numerous to list here.