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jessie.dazzle wrote:

Its still not perfect, and I had the mic 1m from the membrane of the driver (had not yet read Romy's last post where he recommends putting the mic back at listening point).

I would like to stress it again that that positioning of microphones for measurement of en entire acoustic system is a very complicated subject. In some instances the static positioning would not work and the mic needs to be moved. Anyhow, I would like to keep the subject of mic positioning out of this thread. What Jessie you do are relatively simple measurements and in your case the microphone might be at any position – even at the mouth of the horns. The measurements themselves are not important. The important is how your auditable how the experiences correlates with your auditable experiences. So, the data that you collect via measurement will be juts to interpreted differently in case you measure from your listening position vs. you measure at 1 M from a given horn. It is like if you horn axis shot in your shoulder+1’ (like in my case) then where to position microphone for HF measurement: at the location of your head or at the MF horn’s axis. The answer would be – it does not matter for what you measure. Give yours another month and you will not be caring about the absolute response anymore but you will be concerned about the very specific rates of response change. The rate of change might be observed by many means and in many microphone locations. So, pick the mic position that you feel comfortable and stick with it. It will in time give you a sense of “how the given measurement sound” when you just looking at the graph of the given channel will be able to predict sonic consequence of the given solution.

jessie.dazzle wrote:

Yes, it seems you are correct. Arriving at this conclusion alone would have probably eventually happened (well I like to think so!), but I was reluctant to try such a thing because, to be honest, I had always thought you under-used your Fundamentals horn due to the difficulties you had in implementing it. I have often wondered if you were not supplementing the output of that horn via your Injection Channel. I now see (hear) for myself that neither is the case.

I do have difficulties with Fundamentals Channel but not those that you mentioned. My desire do not let the Fundamental Channel to run high is purely deliberate. Running the Fundamentals higher reduces MF texture and vertically offset imaging. The imaging might be brought back by running the upperbass higher but then we have some imagine diffusion (lobbing) + the HF because too heavy and loose lightness. With three channels having that large overlap some music will to onto sonic saturation. It is like having a very heavy meal on thirsty mouth and be not able to drink water… Try to make this setting and listen some symphonic poems like Liszt, Strauss and etc. it will be intolerably- stuffed. I do have the difficulties with my Fundamentals Channel’s lover knee. Here I would like to have 180Hz horns, lie you have instead of my 250Hz horn, but it is what it is. The 180Hz horn would be larger than my current horn however, and I am at a very strict nearfiled environment… so, it is not clear to me if I would go for 180Hz horn in my case. Anyhow, the Injection Channel is not in the picture regarding this matter.

jessie.dazzle wrote:

I took a look at some of the sweeps you've posted for the S2 and Water Drop tweeter; it seems you tend to use a 40dB window... This I think I could manage. I find reading your RTA sweeps seem a bit coarse to me for example when trying to read HF rolloff of the S2, but this may be because you were using something like a 1/3 octave setting at the time (?)

The HF rolloff of the S2 is a tricky subject. It is 12.5kHz in the horn axis with a slight +2dB infliction at 10kHz. I do not use S2 on axis and at the location my head it is around 10kz flat. However, here is where the S2 shows itself off. The S2 has own poisoned caustic resonances at very HF that I found very interesting to use  and that subjectively make the S2’s 10kHz to sound more satisfying then TAD/JBL/EV/ALTEC’s 15kHz. The S2 at the very top has that “sonic thorn” that in my view set it apart from other drivers – I kind of got addicted to it though the “S2’s thorn” in my case (single stage amp and heavy loading) is very much reduced. So, you can’t say that it is juts 10kHz - it is rather the S2’s 10kHz - the very different animal then any other 10kHz.  

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