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Ellam Flex
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GO TO: CROSSOVER CROSSOVER LAYOUT CABINET CROSSOVER KIT MEASUREMENTS 6620 VERSION
Ellam FLEX is just what the
name suggests, flexible. The idea is to make a small two-way from the
venerable 15W/8530K00 - still the best 5" I know of - as an
upgrade/replacement to former Ellam 9800, Ellam XT and W1500/97
constructions. These constructions will disappear from my website as I
think I can do better today with all experiences gained over the last
eight years, not least the
Jenzen
speakers.
Ellam FLEX takes advantage of
the Jenzen front panel designs and features a stepped baffle allowing
proper time alignment of drivers and implementation of true
LR2 filters. The 3-way version will be
Ellam
Flex 3W.
The Sound I could hardly wait after
finishing the first crossovers to take the Ellam FLEX to our living
room and connect to my
GlowMaster KT 88 valve amp. After some tweaking
of tonal balance by changing the value of L2011 - and actually
completely remodel the tweeter section - time was in for some serious
listening. Thus, a wide range of recordings, vinyl and 24 bit were
played and I can understand why some people settle with a
pair of the 15W Revelator minis. Even in our 25 sqm living room they
do deliver a credible soundstage and I'm impressed how the handle a
grand piano with proper weight and tonal balance. The 65 watts from
the GlowMaster have no trouble swinging the Ellam Flax to their limit.
Some serious choral works were
played and proved mid-treble integration on par with the best of my
Jenzen speakers and DTQWT. What they obviously do not is handling the
dynamics of larger speakers - but we can't have it all from ~10 litres
and a 95 cm^2 cone. I went through all the recordings listed here from
the
GlowMaster review.
The Ellam FLEX did all of these demanding recordings without ever giving up on resolution or sounding harsh. This indeed promises very well for the 3-way version. Numerous other recordings were on the spinner, from Eva Cassidy and Johnny Cash to Miles Davis and Keith Jarrett. Even Safri Duo, Samb-Adagio, they handle with punch and drama. The 15W Revelator - despite a predicted F3 of 55 Hz - has the ability to at least make us believe it goes much deeper. I guess it's because what it does, it does really well. Remarkable driver. The Drivers
15W/8530-K00, D3004/660000
and R3004/662000 drivers. Click images to view large.
*: Most 5" drivers will have a rising response towards higher frequences. When we place these on a narrow baffle we have baffle step loss; for e.g. 20 cm width we will be 3 dB down around 580 Hz. These two things combined often leaves a serious bump around 800-1200 Hz and we need to flatten the response here, otherwise the sound will become much too forward. What is seen over and over again is the use of a large series coil for the bass driver bringing down the upper midrange and the result is a dip in the middle midrange (320-640 Hz) which often makes male vocals thin and anemic; we miss some weight in the overall soundstage as there is a significant amount of energy in almost any music in this range. Thus, a low-value series coil and a linearising circuit can solve the problem. For diy people this doesn't impact cost considerably, but for a commercial designer it's three extra components and they mostly take the easy way.
GO TO ELLAM FLEX CABINET PAGE FOR DETAILS ON CONSTRUCTION
Measurements may
give us an idea of tonal balance of a system, i.e. too much or
too little energy in certain areas. Measurements may tell us
about bass extension if far-field measurements are merged with
near-field measurements. In addition to this ports may contribute
to bass extension. Most of us diy'ers do not have access to an
anechoic room for full-range measurements from 20-20000 Hz.
Left: 6600 and 15W response @ 0.5 meter,
10 deg off axis, normalised for 1 metre 2.8 volts. As we rarely
listen strictly on-axis this may display a better starting point for
crossover simulation. The dip at 1.3 kHz is due to all too common
rubber surround resonance. Not much we can do about it.
R1011 = 1 ohm is a bit too bright to my taste and 2R2 is more like it, making a balanced upper treble with still a lot of detail due to the 1-4 kHz range almost unchanged. Right: R1011 = 1.0, 1.5, 2.2, 3.3 and 4.7 ohm. I don't think you'll need 1R0 or 4R7 to find what will suit you best.
Right: Drivers' response and summed response driven from crossover. Point of crossover ~2.1 kHz.
All technical questions at: troels.gravesen@hotmail.com
CROSSOVER
LAYOUT
R3004/662000 version
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