V4.x compatible Bass reflex speakers.
4 Ohm, 1watt. 22mm x 58mm x 9.3mm.
The most popular upgrade for Loksound decoders in the new 4 ohm rating;
Perfect for Loksound V4 decoders. Identical size, Identical performance to our V3.5 speakers
Our famous Bass reflex speakers are now available to suit
the new Loksound V4.x decoders.
designed to enhance low frequency locomotive sounds (ideal for either Diesel or Steam).
The speaker impedance has been designed to match that
required by the Loksound V4.x range of sound decoders (4 ohm), and can be used to
directly replace the standard speakers without any other considerations.
Initially available in three sizes, all with attached
This unit is based on a 40 x 20 speaker, measures 58mm x 22mm
overall, and is a slim 9mm deep.
(ESU Loksound sealed speakers
measure 44 x 22 x 12 in comparison.)
As the developers of this product, we offer full technical
information, which is published below.
Bass Reflex, Technical theory of operation.
In contrast to placing a chamber on the back of the speaker which is (almost)
air tight, a bass reflex system has a port or vent engineering
into the case, which consists of an opening, generally backed with a pipe or
duct of circular or rectangular cross section. The air mass in this opening
resonates with the "springyness" of the air inside the enclosure in exactly the
same fashion as air in a bottle produces a low frequency sound when a current of
air is directed across the opening (try it, it's fun!). The frequency at which
the box/port system resonates, known as the is determined by the cross sectional
area and length of the duct and the volume of air inside the enclosure.
This permits a lower frequency sound to be produced by a
smaller speaker than could otherwise do so. The design type augments the bass
response of the speaker, and can extend the frequency response of the
speaker/enclosure combination to below the range the speaker would reproduce in
a sealed box. The enclosure resonance has a secondary benefit in that it limits
cone movement in a band of frequencies centred around the tuned frequency,
reducing distortion in that frequency range.
||22 x 58 x 9.3.
||4 ohms @ 1000Hz.
||1w nominal. Max 2watts
|Lowest resonant frequency
||330 ± 66 Hz
|Output sound pressure level (SPL)
||78 ± 3db /1w @ 1meter (averaged at
800,1000,1200 & 1500 Hz)
||Max 5% at 1000Hz, 1Watt
||- 25°C ~ +70°C