There are many types of materials which can be used to modify or dampen the mechanical
or acoustical performance of a Loudspeaker cabinet. These range from relatively light materials, like polyester
pile or wools, to heavy and acoustically dead materials like bitumastic. The lighter compositions, have complicated
interactions with the acoustics, but ultimately convert internal cabinet pressure-waves into heat, thereby reducing
the signal level. These interactions occur over a relatively small frequency range. The heavier materials, like
bitumastic, form the basis for mechanical panel damping and can be selectively applied to internal loudspeaker walls
to reduce the level of live panel vibrations. Felts offer characteristics which fall midway between the two extremes.
Below you will find a selection of materials which offer a range of differing
characteristics and which are able to be applied easily in a DIY environment.
foam is an ideal contender for damping the higher frequencies in
speaker enclosures. Coloured grey, it has a closed cell
construction, is easy to bend / fit into a variety of loudspeaker
enclosures and may be cut to shape using a sharp scalpel. This sound
absorbent foam provides a cost-effective and clean method of
installing speaker enclosure damping to your home project. Nominal
thickness 16mm. Supplied in rolled sheet format, 550mm * 1200mm = 1 piece.
Sound Absorbent Foam Sheet, 16mm thick
Description: Foam Sheet.
Pk Wt gms
(2) Herdwick Sheeps Wool.
Genuine British, scoured Herdwick Blend, Sheeps Wool. Cleaned / washed but not mothproofed,
this is the upgrade to polyfill and other synthetic type fillings. Ideal
for stuffing your loudspeaker cabinets and ideally suited for transmission line stuffing. Available in
250gm and 500gm packs. As a general guide, 250gms of wool stuffing will be sufficient per 1 cubic foot
of stuffed volume or 28L, whichever you like. Of course you can use more or less as required.
Herdwick Sheep's Wool, Loose, Ideal for Cabinet Stuffing and TL's
Description: Sheep's Wool.
Pk Wt gms
Herdwick Wool, 250gms Pack
250 / pk
Herdwick Wool, 500gms Pack
(3) Sound Absorbent Felts
Mixed Sound Absorbent Felt.
Used for damping the internal resonances and reflections
in loudspeaker enclosures. This speaker felt is of a mat wool and
composite material construction, 80% recycled wool, 20% cotton mix. The sound absorbent felt is
supplied in two material weights 1700gms or 1100gms per square
metre. Nominal thickness is 10mm or 7.5mm uncompressed. Supplied in
rolled / sheet format. See below for sizes.
NEW additions to our felt range. This felt is 100%
pure Herdwick Sheeps Wool felt. Now supplied in three felt weights of (35, 42 & 48)oz per square yard. The measured
thicknesses are notional and uncompressed. When cut and bent / flexed the thickness tends to expand.
Provides an improved performance substitute over recycled wool / cotton felts.
A heavyweight hard cotton / wool felt available in felt
strips of (30 * 150 * 10)mm and which may be cut to size or shape. Also available
as felt coins 25mm diameter by 7.5mm thick. The material is used to dampen unwanted mechanical
vibration. Ideal for speaker stand platforms or beneath equipment. Non adhesive backed.
Hard Felt Strips & Coins. Sold in packs of 4 strips, 8 coins
Description: Hard Felt strips & coins.
Pk Wt gms
Hard Felt Strip (30 * 150 * 10)mm
Hard Felt Coins (25 Diam * 7.5)mm
(6) Bitumastic Damping Sheet
A heavy grade self adhesive backed Bitumastic damping
material used for sound deadening. Now available in 3 weight
options. Sheets / pads of (600, 300, 150)gms per sheet, The cut sheets are
all (200 by 300)mm and are used for suppressing resonant
panels. The adhesive provides good material coupling to wood panels.
For extra security it is recommended the sheets are tacked / nailed
into place as this will prevent creep or failure / detachment in hot
weather. See our ARTICLE about USING BITUMASTIC DAMPING
Larger sizes are for customer collection 'ONLY', available in the following sizes. For best results
this material should be transported and stored flat.
Bitumastic Sheet. Larger Sizes, Customer Collect Only
Description: Bitumastic Sheet.
Pk Wt gms
Bitumastic Damping Sheet (300*1000*5)mm
Bitumastic Damping Sheet (600*1000*5)mm
* Bitumastic samples.
For Postal Samples of Bitumastic Damping Sheet (DAMPSHT1),
(DAMPSHT2) or DAMPSHT3 please enclose four (4) First Class Stamps in an envelope
along with your name and UK address. Sample size (100 * 50)mm.