LSM Disco

As I had 22W and 10F Discovery drivers around, and also LSM prototype cabinets, I was curious to see how they measure and what would it look like crossover-wise. D2004 was ready for NE3W project, so I made just new baffle for LSM proto cabinets and measured axial responses.

This project was never finished, but shows potential and this driver combo could work very well.

First, 22W 4ohm seems to provide very nice system sensitivity close to 90dB/2.83V/1m. With that quite high sensitivity, and +-5.5mm cone excursion, this driver is capable ~105dB max SPL full space. Here we have 40l BR cabinet tuned to 41Hz. From the graphs, lower tuning ~36Hz would be needed. 

Hmm, maybe 3way floorstander, 50l cabinets, plus 15M Discovery, and SS 9130 would definitely make nice system. Just thinking of next plans.......

10F driver is very flat, except that small bump at 1500Hz. I remember seeing that in Vifa TC9 measurements too. For my crossover modelling I addressed that with RLC, but it is possible listening tests would show it is not needed.

D2004 and 22W waterfalls are reasonably clean and don't suggest any special crossover elements needed. 22W broad bump at ~3kHz will be addressed with small RC element parallel to woofer primary coil. 10F bump  at 1500Hz will be probably needed to be suppressed by RLC.

Several crossover versions were modelled, including all LR4 version, and it looked really well, nothing against that, except higher crossover components count. 

Less complex crossovers were modelled, and they are shown below. They provided nice results, note especially good phase tracking in wide frequency ranges.

Full set of horizontal measurements 0-90deg is needed, to evaluate Power response and DI to see which crossover version would be better.