SpeakerTalk

SaSi · Senior Contributor 200+ Joined: 24 Aug 2008 Posts: 256

For some time now I have been considering a large project, along the lines of the KM1 or the Blade: 4 woofers, 2 midranges and a tweeter in MTM configuration.

I am thinking about 4xB139, 2xB110 (or B200) and a T33 or T27, driven each by their own LM3886 following an active crossover.

The idea is to have the 4 woofers mounted to the sides of the rectangular enclosure with magnets constrained to reduce vibration and build the enclosure as a sandwich of thin plywood and bitumen sheet layers (Constrained layer panels).

Any ideas on that? Especially on the drivers? I have plenty of B139s and almost all of the B200 (rabbit ear or 3 screw) versions and I really want to put them into good use.

The resulting units can be considerably tall (150cm) and will operate in a large living room/dining room area of about 100sqm.

Garethwatkins · Posted: Tue Feb 16, 2016 12:45 pm Post subject:

That sounds like a fascinating project. Have you looked at the MiniDSP website? They have a range of easily programmable active crossovers. Even if you don't want to go digital they can still be used as a development tool. I built a fairly unesoteric 2-way, and with the help of a very skilled BBC audio engineering colleague to set up the DSP, ended up with a really nice system powered by a pair of Quad 306 amps. My only concern would be the T27's power handling in such a mega-system.

SaSi · Senior Contributor 200+ Joined: 24 Aug 2008 Posts: 256

I have checked out minidsp and these sound extremely nice. But I already have a purpose tasked Behringer DCX2496 unit that can provide the stereo by 3 bands I need.

But I toy the idea of combining a minidsp board with the array of gain-clones.

I have several systems employing the T27 (Corelli, Calinda, R104ab, R101) and none of them is treble shy. In fact, the main criticism on the T27 is related to it being on the bright side.

I am not aiming for 120dB output, just balanced load across each driver, low excursion and low distortion. Hence 1 tweeter, 2 mids and 4 woofers.

Did a couple of winisd simulations on the B139 and it's behavior in vented systems is interesting. Thinking of checking out how it combines with it's radiator brothers. If a radiator is used per driver (which is on the low side) the looks should be intimidating. I'm afraid it borderlines with Kabuki territory.