PMC

PMC is a UK based, world-leading manufacturer of professional monitor and audiophile speaker systems.

PMC designs feature its uniquely engineered Advanced Transmission Line technology (ATL), which provides, high resolution, wide bandwidth signal response across the complete product range. Proprietary drive units, electronics and cabinet engineering, provide unrivalled tonal accuracy, clarity and dynamic range throughout a range of designs, extending from the world's smallest TL design, the DB1+, to large scale active control room monitoring systems such as the flagship BB5-XBD Active.

PMC monitor systems are in service with most of the world's premiere music and film sound recording studios, broadcast companies, post production and audio mastering facilities.

Taking the lid off
The PMC Transmission line design
The transmission line (TL) is the theoretical ideal and most complex construction to load a moving coil loudspeaker design. Theory is all very well but it does present us with a rather large cabinet, as the perfect transmission line design would have an internal structure that was totally acoustically absorbent to the entire rear radiation from the drive units. This would make it infinitly long, which even Stephen Hawkin would have trouble visualising. The most practical implementation is to create a long tunnel within a cabinet by introducing internal partitioning that folds the line up and down the length of the cabinet. At the very end of the line there is a very specific size of hole that vents directly into the room. A major benefit to this construction is that the labyrinth braces the entire structure from beginning to end. This nearly eradicates cabinet colouration created by the effects of the outer walls of the cabinet flexing. Cabinet integrity and internal panel damping are essential to produce a successful design due to the TL's inherent ability to produce phenomenal LF extension, even from a modest box.

The main driver is placed at one end of the TL, which is heavily damped with absorbent acoustic material. The most predictable and accurate absorber is a highly specified foam material that took a vast amount of R&D to derive the correct formula of profile, pore size and density of the polymer. The foam, probably the least visually dramatic of the components is tremendously important. It has to absorb all the upper bass frequencies and allow the lower frequencies to exit the vent at the far end of the line in phase with the main driver. It must also be exactly specified to ensure a consistent and balanced backpressure on the driver by interfacing smoothly with the column of air within the line. With too higher damping, the driver cannot move freely enough, and conversely too little damping produces a lack of control and the result is a LF response similar to that of a regular ported design.

Producten:o.a

HiFiluidsprekers:  wafer1,  wafer2,  AML1,  DB1,  TB2,  LB1 classic,  LB1 signature, FB1+ ,  GB1,  OB1,  CB6,  IB1,  IB@,  MB2,  MB2 XBD,  BB5.
Pro Monitors:  AML1, DB1S+, TB2S+,  LB1 classic,  LB1 signature,  AB2S,  LB1S,  MB2s,  MB2S XBD,  BB5-P.

Acitive Systemen:  DB1S-A,  TB2S-A,  AML1,  MB2-A,  MB2 XBD-A, BB5-A,  BB5 XBD-A.

SubWoofer: TLE1,  XB1,  XB2,  XB3,  SB100.

PMC Limited
43-45 Crawley Green Road
Luton
LU2 0AA
United Kingdom
Tel: +44 (0) 870 4441044
Fax: +44 (0) 870 4441045
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