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Ok, I did play today with the MiniMe. I have to tell that then it turn black I kind got soften with it does not look to me as large and violent as I initially thought. I made some measurement and some listening. I peaty much know what I want to be and it took no time to make the MiniMe to sound more or less civilized.

The RAAL tweet is invariably inverted to MF and with crossover exactly as at in the drawing above. I do not feel that I got 93dB, I would more likely see 91dB, but it is OK, it is a ribbon and it might run softer. I had a lot of problem with MF driver. I have 4 LE5-2 drivers and all of them sounded very poor, with sensitively around 88 and a huge peak at 7khz. I figured that they might be discharged. They have an OK tone but not usable in MiniMe as they are now. I have a pair of 2105, that are the very same LE5-2 and they were absolutely perfect. I though them in but then had the same 5-6db peak at 7khz. I have no idea where it come from – the do not have the ugly JBL metal dust caps… I decided to let them to start to roll at 4.5K, unit the peak at 7khz and contra-balance to the engaging filter - I was .2mH large air-core coil. The MF was near fixed. It still has a small heal in there but not the one that I would feel need to be address as during my “quartet test” I did not detect any problems. I know, I know, the thinking reader would ask: “Romy, what are you doing? The story with Vitavox repeat itself? You again use the driver’s resonances in an auditable range, refusing to cure them?” Sure, I do, good luck to you.

The MF and bass are in phase. The woofers as I expected did not want to roll off – the freaking inductance of the driver sink the filter inductance. So I stated with a huge 7H air core coil. It has too fast roll off sonically and RTA showed the same.  I went for my favorite low-pass design techniques that I use for years – the “Trout Techniques”. The technique is very simple. I drive the LF section with a long cable that come across my listening reference spot. At the spot in the cable colder a coil intentionally larger then necessary – who know HOW those woofer’s VC will skew the coil up. The CD player plays in look the final from Schubert’s Piano quintet in A, the infamies Trout Quintet. At the listening spot I am listing the music and holding the large coils with signal passing through it, very slowly taking the turn out of the coil, looking when the integration between the upper knew of bass and lower MF will be right. I end up at ~5.1H that is around 1000Hz for woofers – well let it be so. I did not deal with the port and the lower knee of the LF section. I will leave it for later and have a large 4” hole in back –  in fact it is not bad but I am sure will be better.

So, the speaker is well balanced now and generally listenable. Yes, I took 16R LPAD and was forced to roll MF and tweet foe a few DB – do not forget that I have 16R of 4 woofers. Yes, I but a lot of sensitivity and I think now I am at I think 88dB-89dB, I did not measure it. I took a SS 70W amp with STR ships and decided to listen it. So, how did it sound? Well, I am sure that simpletons of the Joe Roberts caliber would consider that it was OK, in fact it was impressive when I was playing the pop cuts from my measurement disk. (I like the Sheffield Test tracks). When I went for civilized music it was revolting, I am not kidding. I was listing and even wondering if I need to make the second speaker for THAT result. I thought that it might be an amp and it was – I switched to 6E5P-2A3. It of cause has some severity but no power. Come on, it is a flimsy 2A3 driving 7K – too much to ask. I tried the full-range Milq that is 12W with single plate. It was better but still not where I would like it to be. I know what I need to try – there is the only one powerful amp the I would trust to do the job – the Lamm M1.1 but it is not the amp for MiniMe requirement. So, I was sitting and scratching my back – what an idiot – build a speaker and was not able to drive them.

Hey, does anybody in Boston have a single M1.1 that you can borrow me? At least then I will be able to found out how it might sound and would go from there…

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