Go to on this page:
"4" for 4 Ohms, "R" for ring-radiator. Just to get the name in place.
15W/4531G00 is the more lively
sibling in the Revelator 15W family of drivers. "30" means coated, "31" is un-coated. "45" means
4 Ohms version, hence the increased sensitivity compared to the "8530"
driver used in
Ellam FLEX and
Ellam 98 mkII.
Un-coated means its cone has a different sonic impact on the overall
presentation. A little more lively, more
lush, if you will. To balance this I picked the classic ring-radiator,
providing a balanced and very neutral sounding treble.
The "4531" may sound more dynamic compared to the "8530" due to its low-resistance voice coil,
drawing more current from your
amplifier and just simply plays louder for the same volume setting.
At the end of the day a matter of taste.
This speaker should
possibly be compared to the classic
Unfortunately I don't have the XT for comparison, so I can't tell the
The crossover provides an extremely flat frequency response from its
2nd/3rd order topology, similar to what is used in the Ellam XT. Not
having the stepped baffle like Ellam 98 mkII and Ellam FLEX,
necessitates a steeper crossover to provide proper phase integration of
the two drivers. It's a trade-off, but a loudspeakers are always full of
For those with limited woodworking skills, this speaker is designed for
Dayton 0.38 ft^3 (10.8 litres) cabinet.
Still, you do have to be able
to use a router to make drivers' rebate. Obviously you can make your own
cabinets as long as you stick to front panel dimensions, drivers'
layout and volume. The two first are imperative to make the crossover
work as intended.
The cabinets come with a ready made front grille and I
think it's the first time ever I've launched a speaker with a front
grille. As you will see below, the front grille has quite some impact on
frequency response and for any serious listening, I suggest you leave it
off. Use it when your neighbor's kids pay a visit and want to check out
drivers' compliance. They usually do.
Click image to view large
2-way mini from ScanSpeak 15W/4531G00 Revelator midbass and ScanSpeak
System sensitivity: 87 dB/2.8V. 1 meter
Impedance: 4 Ohms.
Point of crossover: 2.7 kHz.
Bass extension: - 3dB @ 47 Hz.
Amplifier requirement: Minimum 10 watts.
Power handling: 60 watts (ScanSpeak specifications). Please read
power handling, it's not that simple, and please remember that any
burned driver is a misused driver!
BACK TO INDEX
BACK TO INDEX
Simulated horizontal (left) and vertical (right) dispersion.
Optimal listening height is between bass and tweeter.
Place the speakers on 60 cm stands and tilt 3-4 deg depending on your
As always distances to floor, rear wall and side walls plays a major
role in overall sound.
In my listening room I have 100 cm to rear wall (from front) and 180 cm
to side walls.
BACK TO INDEX
For 10.8 litre we see F3 = 47 Hz. Port tuning
(Fb) 45 Hz.
The Dayton cabinet makes 10.8 litre. You can
realise this from standard 22 mm MDF by making a rectagular cabinet of
203x264x355 mm (WxDxH). Add a vertical brace like the Dayton to make
room for the crossover.
Use tape to prevent the router from damaging pre-painted front penels.
DO NOT for get to chamfer the bass driver hole to allow free air
Checking out driver routings.
Make sure to hit the right depth for the 15W driver, 5.5 mm to allow room
for the gasket and make a smooth flush mount.
Left: Cut a 80 x 900 mm piece of 8 mm felt and place in front part of
Right: Cut two pieces of 100 x 320 mm 8 mm felt and place on sides of
rear chamber. Ad felt to top and bottom as well.
Left: Crossover mounted on rear panel. Place 15x10 cm piece of
acoustilux above port.
Right: Fold a piece of 30 mm acoustilux, 20 x 20 cm, and place above
crossover on rear panel.
BACK TO INDEX
A few comments on MEASUREMENTS before you start
interpreting all the readings below.
First of all, if we think measurements will tell us how a speaker
sounds, we're wrong. The perception of sound is way too subjective to be
reflected in any measurements we can perform. A loudspeaker system is
meant to give us a satisfying idea of an acoustic event and for some
people a pair of 5 USD ear-plugs are enough, others spend 200 kUSD on a
truly full-range pair of speakers - and the latter may not be happier
than the former.
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.
What cannot be seen is what kind of bass performance we get in a given
room. Bass performance is highly dependent on in-room placement of your
speaker and the same speaker can be boomy in one place and lean in
another. Actual SPL level at 1 meter distance and 2.8V input is useful
for en estimate of system sensitivity and combined with the impedance
profile may give an idea of how powerful an amplifier is needed to drive
the speaker to adequate levels.
What measurements do not tell is the very sound of the speaker unless
displaying serious linear distortion. The level of transparency, the
ability to resolve micro-details, the "speed" of the bass, etc., cannot
be derived from these data. Distortion measurements rarely tell much
unless seriously bad, and most modern drivers display low distortion
within their specified operating range.
Many people put way too much into these graphs and my comments here are
only meant as warning against over-interpretation. There are more to
good sound than what can be extracted from a few graphs. Every graph
needs interpretation in terms of what it means sonically and how it
impacts our choice of mating drivers, cabinet and crossover design.
What measurements certainly do not tell is the sonic signature of the
drivers, because cones made from polyprop, alu, Kevlar, paper, glass
fiber, carbon fiber, magnesium, ceramics or even diamonds all have their
way of colouring the sound.
Left: The important midrange! Here we see the impact of RCL2031. Right:
Flat midrange and smooth roll-off.
Response of driver driven from crossover. Point of crossover = 2.7 kHz.
Right: Inverting tweeter polarity creates a deep suck-out around point
Left: Final response of left and right speaker.
Right: Impact of front grille (green). As expected front grille frame
doesn't better the nice and smooth response. Leave it off for
BACK TO INDEX
All questions regarding purchase of kits,
please mail Jantzen Audio at
All kit and component prices may be
subject to change and are always to be confirmed by Jantzen Audio
Download Kit Sales Presentations
BACK TO INDEX
This is a pretty tight layout. Make sure not
to short any wires.
You may stack the additional tweeter attenuation resistors on top of
R1011 (but only connect one as seen below).
I glued R1011 alternative resistors on top of C1021.