HL1
£6,500
The HL1 is a new horn loudspeaker, developed out of
original research undertaken by Aspara.
It combines the effortless clarity of horn loading with a
natural sound balance and low levels of colouration
The Aspara HL1 is really a direct descendant of the Impulse
H2/Ta’us loudspeakers.
In the larger Impulse loudspeakers, mid-frequencies were
reproduced by a horn driven by a Seas 11FM drive
unit. In many ways the mid-horn /Seas 11FM
combination of the H2 works well, but it doesn’t quite have
the ’grip’ of a small diaphragm pressure driver with a
powerful magnet assembly, feeding a suitable horn. The 2”
titanium driver in the new HL1 is specified as having a
sensitivity of 108 db for 1 watt.
This doesn’t just mean miniscule amps can be used to drive
it, it means that much more of the power being fed to it is
being converted to useful sound output, so there is much
less stored energy and the transient response is better.
Working into a well designed horn, such an efficient driver
can equal a panel speaker in terms of clarity and even
approach it in terms of low colouration, if the horn is not
compromised in its size and flare rate.
Pressure driven horns can have problems at their throats.
To avoid possible negative effects here, the new HL1 has no
less than 60 small passageways leading to the horn. Using
the small titanium diaphragm pressure unit, it is possible
to cover the whole range from 800 Hz upwards with one
driver, without a separate tweeter. Just one crossover,
fairly low down in the audio range, between the bass and
high frequency drivers, means that the transition between
them is much easier to disguise and the speaker system can
be made to sound ‘seamless’.
Perhaps the biggest problem with horn speakers has been the
theoretical size of horns necessary to excavate useful
amounts of bass. A superficial look at the theory suggests
that the acoustic resistance curve of the horn largely
defines its low frequency performance. But, there are a
number of factors, all interrelated, which influence this.
When these are taken into account, horns don’t need to be
truly colossal to work in the bass.
The HL1 bass horn actually has a mouth twice the area of
the Impulse H2 , though the flare rates are similar. The
HL1 driver is 300mm in diameter compared to the 200mm
driver in the H2. The larger driver in the HL1 is of course
more sensitive.
The aim of designing the HL1 has been to produce a natural
sounding loudspeaker which is relatively sensitive and has
the dramatic realism and presence horns produce so well.
Low
Frequencies
Horn type - Modified exponential.
Driver - 305mm (12”) drive unit with paper cone.
Sensitivity - unloaded average sensitivity 100db 1w @ 1m.
Mid
/ High frequencies
Horn type - Radial.
Driver - compression type with titanium diaphragm.
Diaphragm dia. 50.8mm Av.
Sensitivity 108db 1w @ 1m (attenuated in HL1).
Dispersion - 75 degrees horizontal. 60 degrees vertical.
Crossover - 1st order.
Construction cabinets made from solid hardwood and birch
plywood covered in the finest veneers.
Dimensions height 43ins width 18.5 ins depth 18.75ins
Weight 52Kg
Finishes A number of veneer finishes available
HL2
£2,600
The HL2 is a small loudspeaker with a surprisingly large
sound.
The
tall narrow enclosure conceals a long folded pipe. The air
column inside this enables the speaker to grasp hold of the
air very well.
The
result is a big speaker sound from a small driver. At the
same time, with it’s light cone the driver is able to
respond fast to rapidly changing audio signals, producing a
sound of great clarity.
- Main Driver : 135mm (5 1/4”) doped, paper cone driver mounted in an enclosure based on the quarter wave column principle. A carefully designed flared vent forms the acoustic interface with the listening room air.
- High frequencies: 19mm (3/4”) soft dome tweeter. Crossover - 1st order.
- Construction: cabinets made from solid hardwood and birch plywood covered in the finest veneers.
- Dimensions: height 41.5ins. width 6 ins depth 12ins
- Weight: 17.2Kg
- Finishes: A number of veneer finishes available.