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bigwig bigwig is offline
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Default Fingered tweets the little b*%8&^rds

On 22 Dec 2008, 23:23, fryzz wrote:
On Dec 16, 7:14 pm, bigwig wrote:

**** sorry Fryzz,


Hey, no problem. *You know, you could just plug the hole and set the
tweeters on top. *Maybe in their own little box with a stout grill to
protect them from the ....ahem....environmental hazards?

Didnt see the link. I guess we pay well over the odds. The Seas units
I am looking at cost that. I could risk it with customs and excise for
that price. even if they sting me like they did on the trannys I got
from the US its still a good deal.


Ah, I see you're in the UK. *Morel is British, so you can probably get
them cheaper than I can.

* *I thought of ribbons. What was wrong with yours?.


They began to sound distorted, after 25 years of service. *I took them
apart to see what's up, and the conductors were coming loose from the
diaphragm. There was also some discoloration and warping, looked like
thermal overload. *So, yeah, I blew them out :-(. *It might be
possible to make a new diaphragm, but I wanted something more robust
anyway, so I went with the Morel domes. *I really like the low
distortion and fast transient response of a decent ribbon, the problem
with is that all the ones I can afford to buy are tiny and fragile,
even if they do sound good.

After I got into crossover design, I tried both 12 dB/octave and 6 dB/
octave networks. *I was able to get excellent amplitude response with
the 12 dB/octave networks as long as I was willing to tolerate 180
degrees of phase shift from one end of the passband to the other.
With 6 dB/octave filters I was able to design a network that is, for
all practical purposes, both amplitude and phase flat over the entire
passband. * I tried out both networks, and the 6 dB network gives an
incredibly natural and well imaged sound compared to the 12 dB, as
well as being considerably less complex, hence cheaper and easier to
build. *The downside is that the drivers see more energy outside of
their passband, so power handling and distortion are to some extent
compromised. *That's probably why my ribbons died.

So, to make a long story short, I needed a more rugged tweeter to
accommodate my changing preferences in crossovers. *After looking far
and wide, and reading many, many spec sheets, I decided I really like
the Morel drivers. *It is my observation that their parts offer
outstanding distortion and frequency response characteristics, and
handle four or five times the power of comparably priced competing
units. *Transient power handling is specified both in terms of the
thermal capacity AND the acoustic output. *If there is better value
for the money being offered elsewhere, guys, I would surely like to
know.

My speakers consists of a stereo pair. *15" acoustic suspension
woofers in 3.5 cu ft boxes, giving 3 dB down at 43 Hz, rated at 150
watts. *The woofer excursion limits at 110 dB. *The midrange is a
Morel MDM-75 (no longer available, the MDM-85 is it's replacement),
and the Morel CAT308. *All drivers are 90 dB 1 watt 1 meter. *I drive
it with an old Ampzilla, 250 watts/channel. *They sound great at any
volume level up to the max that the amp can deliver, with any type of
program material, accurate enough and clean enough that occasionally
it happens I am fooled into thinking a recorded sound is real. *Kind
of spooky. I have about $800 worth of material in the pair, which
includes prefabricated cabinets.


Sorry I have not got back before!!!!.
You have 15 inch woofers in 3.5 cu/feet I have been interested in
this kind of arangement before. OK I admit it was in a friends car
with dual voice coils and very low output impedence amp ie 0.001 ohm.
The damping factor is key.
We had some admittedly crappy Sony amps x2 in bridge. In usuall car
bull****t they were rated for 100W RMS per channel and bridged 400W
into 1 Ohm. Funny thing is they did actually give this x2 so two amps
800w RMS!! Sounded amazing. Its the first time I have heard bass
produced this well. A sort of servo effect.
Thing is everything was shaking and it was all chaos. HI Fi I think
not no not, but hey it was very, very nice. At least that was what was
I was told. Yep insane, peaky resonant, but lovely.
I dont have the occasional KW to play with, the smalll closed box
still looks good though.

but the likes of REL and others use the small box very we