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I am quite fascinated with the result that I might get from MiniME and at the same time I am defensive with the direction it takes. Anyhow, here is how it stands…

The decision to go for MF driver was I think right one. Even the 70-20RX tweeter has some “tools” that enable it to work more of less confidently in MF but I never exited about tonal capacity of ribbons. Also, I would like to make MiniME to be able to play loud and with less compression and therefore I would need some headroom between the lower knee of drivers and their crossover point. So, the 3-way with a good band-pass MF driver is a reasonable, I guess, direction to look, even though I might use MF not as independent channel but rather as pedalpoint for tweeter to woofer WITH the woofers, not to fulfill the gap evenly between LF and HF but rather to help to the ribbon and bass driver to care MF.

A guy who read my site sent me to try the JBL-5-2. I always liked those drivers however; I knew LE-8 and never tried the JBL-5. Playing with JBL-5-2 I figure out that it might be exactly what I need. It has 95dB sensitively. It has the right tonal nobility and it is small. The driver is slightly less dynamic then LE-8 when crosses at the same frequency of 1000Hz. I made a number of experiments with it and end up listening the JBL-5-2 with 25uf cap. That makes approximately 800Hz crossover point. It is possible to drive LE5 lower but then at higher volumes the driver gets compression sooner. Ironically the HF section of the driver is falling apart faster with higher volume. So, I was roiling it off and off and end up with and 0.31mH coil, that makes approximately 4000 crossover point. In fact rolling it even lower sounds more right to me, probably down to 1-2K. All together JBL LE5-2 in 800Hz-4000Hz region the LE5-2 do OK, not perfect but OK. I bought the JBL 2105 – the pro version – I might sound different – who knows…

http://www.audioheritage.org/vbulletin/showthread.php?t=5706

There are 3 things that attract me in JBL LE5-2 driver – the sensitivity, some tonal qualities (not overly thrilling but better then others) and the absence of the thing that annoy me. I mean the JBL LE5-2 is quite neutral driver in term of character, partiality and bias – this is important for me as I would like do not deal with it in this loudspeaker. It is possible that there are more capable 4-5” MF drivers then LE5/2105. I spoke with a number of people who proposed to me different solutions. For instance the sound like knowledgeable guy from Planet 10

http://www.planet10-hifi.com/

…proposed a number of Fostex solutions.  I do not know - I have seen so much negative result from Fostex side (perhaps improperly implanted) that it makes me prejudicial… From what I have seen the Fostex always loose correlation with sounds when volume goes up. The Fostex-like drivers might work in sever high-pass through, but the 6dB-7dB sensitively is not nothing.  I wonder what would be the new Görlich sensitive, the old one were at 87dB…

So, I have the tweeter, I have the MF driver, I will have my Malaysian woofers. The LE5 is 95dB sensitive the Malaysian woofers are 90.5dB at 1000Hz. The 4 of the woofers would do +6dB that would be just slightly above LE5-2. In addition it will be in array that would make it integrateable at 1-2 db higher. The RAAL 70-20RX is 93-94dB but 96-97dB effectively. That would make the target sensitively of the entire speaker somewhere around 96dB, here and there…

What however, bother me in this idea is that introduction of MF screw up my entire idea of the MiniMe’s simplicity. The 5” thin and straightforward tower with a few brasses is becoming just a dream. The MF driver shell sit at more or less ears level, the tweeter might be above. However, the MF driver needs to be isolated from the pressure of LF drivers, I was trying to use a back change on JBL and I did not like it. So, the speaker shell have sections and waste some volume of the effective speaker height - I do not want to make it too tall.  So, the complexity of the enclosure increases and at this point I do not think that my regular machinist would be able to do it at cost-effective fashion. I am not going to do any enclosure work myself, so it might need lead to bringing some speaker-building specialist to help. Thos guys use wood and wood would bring thickness – bye-bye the 5” front baffle… perhaps I need to make it with ¼ steal sheets and forget about it? I do not know at this point. It is become more complex then I would like it to be… Does anyone who read this know any machinist from New England who would LIKE to build loudspeakers (send me emial if you do).  I am afraid that my machinist when I drown for him all those steal or G10 labyrinths and sections would sent me to hell.

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