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Thanks, Romy, for your generous reply. I won't try to address everything about everything, but let me bore you with a mini-history of what is going on with my playback so you will understand where I'm coming from and where I'm trying to go. And how I wound up with the Milq in the first place.

Back in the days when I used the ANJ, I was using a pair of the small Hoerning speakers. These were fine, but you got the sense that it was really a 4-way speaker with one of the channels – mid-bass – removed. Or you might say it is a 2-way speaker with a built-in subwoofer. Anyway, I noticed even with the huge Hoerning “Alkibiades” towers, that as you listened you could “see” the missing...maybe pair of 10” low-mid/upper-bass drivers per side or maybe 12” driver. But Hoerning did not go in that direction – in fact his new big speakers use 16 8” bass drivers per side but downsize the midrange driver from the 8” Lowther DX3 to the 6.5” DX65, which is not nearly as good sounding as the 8” one, first of all, and also makes the one stand-out problem with the old version audibly worse. Anyway, I decided more or less at that moment that I ought to try to build a speaker system myself.

In the meantime, I had heard some horns for the first time, just a pair of old YL compression drivers in metal horns which I stuck on top of my Hoernings, and was seduced. I was not really ready to start a construction project, so I just bought a pair of 2-way horn speakers from Aspara Acoustics – a 12” Precision Devices driver and a sort of radial horn mounted vertically on top. It was not long before I realized that now what I had was actually a 5-way speaker with 3 channels removed. There was no real “bass,” and in fact no tweeter at all, but more importantly there was no midrange anymore. I decided that “audio” was getting way too complicated and was detracting from my enjoyment of music, and I impulsively sold my entire system. I later wound up with a single-driver speaker from Audio Tekne (with a Diatone 610 in a leaky box) and drove it with a push-pull 300B amp. I moved my new system to a small room in my apartment was happy for a long while!

Then I moved to a place with only one large room, and the Diatones just sounded diminutive and “lost” in there. I figured, maybe now is the time to fix those old audio problems. My logic was, I did love that 6” Diatone driver, so why not try a 12” alnico driver and put a horn on top, then look for a midrange driver to put in-between. Last, I would worry about deep bass.

This plan did not work, at least not at first, because the Altec 414 I started with is a crappy and bloated sounding driver, overrated in every way. I did discover the JBL 2440 during that time, which I still use. To replace the Altec, I first tried the 12” alnico driver from Supravox (285-2000). This driver is also a headache for 2 reasons. It has such a strong magnet (2.1T) that it is impossible to get any mid-bass out of it. Second, it has a nasty sharpness around 1-2kHz, which, I am told, is due to the fact that the phase plug has a neodymium magnet inside of it (??!!). I used a series resistor to lift the Q, but I could not put up with the “veiled” (from the resistor) or the piercing (from the phase-plug) for very long. I went instead for the 285GMF, which has a more reasonable magnet (1.4T).

As the transparency of my system began to increase, I discovered that my push-pull 300B amp was actually awful sounding (even though I had no complaints when it drove the 92dB Diatone). I tried several 300B SET amps, i.e., middle-market ones, and these had no bass control whatsoever. I was always high-passing the 285GMF, even with air-tight enclosures. Then I thought: hmm, why don't you get someone to build you a Melquiades amp!

Fast-forward to the present, and I still have that same problem I started with. Namely, there is no “mid” (what I am calling 400Hz-1000Hz) in my setup. If I use the GMF in a high-passed bass-reflex arrangement, the upper-bass really comes to life, but the mid becomes thin and washed-out. Mostly to avoid port spillage issues, I keep it sealed, and though there are no obvious problems, the sound is fairly flat, boring and literal. But as you lift the volume, you realize that the midbass is doing a lot of things that you wouldn't normally expect. It's very tight, but also “broad” and expressive.

The reason I ask about using a DHT “add-on” amp for my non-existent midrange driver (and which would also drive the 2440) is that I worry that I will never find a 6” or 8” driver to play along with the 285GMF. This is partly because of level matching, but also because as you increase the inductance on this “woofer” it sounds more and more veiled, slow and boring. So if I am going to introduce another amp, I would ask it to play from 400Hz up.

But the idea of using different combinations of sections from the LL1693 is interesting, and perhaps I should buy a pile of drivers and start experimenting. Just browsing ebay, you notice lots of things, like this alnico 8” driver with Fs 100Hz and 97dB sensitivity, pulled from a garbage dump:

Who knows. I would like to use such a driver in a Voigt pipe (or I guess sealed since the Q is something like 1.3), then go back to high-passed bass-reflex on the mid-bass driver.

As for my allergy to the amorphous-core OPT's in the high range, it's just a sense of raw, as if all the mechanical elements of the tone were chipped away like flecks of rust, then sprayed into the room a fraction of an instant before the timbre. I managed to counteract this obtrusive sense of distortion, on digital, with a warm and puffy sounding NOS DAC using microphone transformers at the output. FM tended to sound fine. But I was getting headaches with vinyl, even with lush sounding cartridges, and I got really tired of that DAC. With steel-core, the sound is much smoother. At least coming out of the 2440.

-Darren

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