Hello all,
My name is Robert Miller. I am borrowing this account from a close friend, because my account has yet to be activated, and so far I have been unable to post under my own account. If there are any moderators who can help me correct this problem (It's been almost a week) please email me at [email protected].
My problems began when I switched out my ADS array for a pair of L250s that I purchased on eBay. As soon as I finished the refoam job on the bass drivers, I gave them a good listen. As offensive as this may sound to those of you who admire this speaker in stock form, I found it to be rather disconnected, that is to say that not all of its components were working in harmony. It wasn't what I had expected from a speaker of this caliber, especially after reading about the history of its development and the man responsible for its design. I make no claim to be the ultimate arbiter in audio reproduction equipment, so I will simply describe what I heard and what I did to correct it, at least in part.
Upon my first listen I noticed an incredibly dynamic speaker with high efficiency, a very upfront sound, and probably the most natural bottom end I have heard yet, but the mid to upper ranges seemed disconnected and unbalanced. Human voices, especially female vocals, did not sound natural. The tweeter seemed to be on its own, buzzing away, and leaving the LE5 somewhere in the dust.
Before 20 minutes of this test had passed, I quad-amped the speakers using my Ashly XR4001 using four Hafler TransNova amplifiers. With a little scrounging around the Lansing Heritage site, I found the stock crossover points to be 400Hz, 1.5kHz, and 5kHz.
The Ashly active xover affords me 24 dB/oct as opposed to 6dB/oct in the stock crossover. I suppose theoretically this is good. With the stock crossover points dialed in, all that should have been left to do was adjust the individual levels of the drivers and perhaps play a little with the response bump at the crossover points.
But it did not turn out to be that simple. No matter what I did, I could not get the tweeter to blend with the LE5. It remained disconnected and harsh. Also, the soundstage lacked space and detail. For example, there is one recording that I have which has a rain stick. Ordinarily this recording yields a vibrant tangible auditory illusion filled with prickly dynamic nuances that stimulate the ears and imagination, but instead, it sounded dull and muffled, as though it were trying to break through as if my speakers where waterlogged!
Eventually, through my "PrimiTech" tuning methods I settled on new crossover points. I settled on 200Hz, 1kHz, and 4 Khz, with a 2dB bump at the 200Hz low to mid-bass crossover point, to warm up the sound a little.
I am assuming that the 8" midbass driver may be rolling off down there because of the small enclosure, this is only a guess though. But Wow! what a difference! I have been listening to the speakers in this configuration regularly for over a month now and every time I play them, I am impressed.
I am not so shallow that I admire only what I have put my hands into, they just simply sound great
So, after this brief history, now for the questions.
I still find the tweeter to be a little harsh, and was wondering if switching to the titanium tweeter and polypropylene midrange would make a tangible difference? I assume that this change would essentially upgrade my L-250's to 250ti's.
I noticed that in the JBL literature for the 250ti, they changed the crossover point up 200Hz on the tweeter. I am assuming they did this because the midrange was marginally more capable.
Sincerely, Robert Miller.
-Edited by Alan Fletcher
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Originally Posted by Alan Fletcher
