Danish Audio ConnecT
Danish manufacturer of high end audio parts for hi-fi, and home theater. Products include stepped attenuators, balance controls, input switches, phono stages, RIAA preamplifier modules.
http://www.dact.com/

Herbie's Audio Lab
Microphonics-absorbing audio accessories, including the 'HAL-O', vacuum tube damping instrument and "square footing" component feet.
http://herbiesaudiolab.home.att.net

V-Cap Audiophile Capacitors
Reference grade Teflon film and tin foil audio capacitors.
http://www.v-cap.com

Dahlquist Parts & Service
Parts, service, and upgrades from "the Original Dahlquist" staff of New York.
http://dahlquistspeakers.com/

E J Jordan Designs
Manufacturers of drivers custom designed for hi-fi system manufacturers but also for sound reinforcement, broadcasting, defense, medical and telecommunication applications.
http://www.ejjordan.co.uk/

High Frame Industrial Co.
Manufacturer of loudspeaker components, including cones of various size and materials, grilles, caskets, and terminal cups.
http://www.highframe.com/

Honsound Electronics
Manufacturer and exporter of woofer, boom box, tweeter, car speaker, multimedia speaker and other car accessories.
http://www.honsound.com

NuWay Speaker
Makes speakers components such as spiders, dust caps and speaker cones.
http://www.nuway-speaker.com/

Plitron
Designs and manufactures standard and custom toroidal transformers.
http://www.plitron.com/

NXT Sound
British thin-screen speaker technology caused quite a stir when announced, lots of OEMs using it.
http://www.nxtsound.com

Black Art Audio
Designers and manufacturers of hand wound transformers for audio.
http://www.jeack.com.au/~lucas/

Raleigh Audio
Manufacturers of vacuum tube kits for the DIY hobbyist to build a preamplifier or digital-to-analog converter with a line stage, DAC and power supply. USA.
http://www.raleighaudio.com

Ciare
Manufacturer of drivers for home, cars, professional and electronics parts. Italy.
http://www.ciare.com/

PHY-HP
Manufacturer of driver unit, cables and interconnect.
http://www.phy-hp.com/

Tone Doctor
Manufacturer of CabMojo and ComboMojo brands speaker switching products. USA.
http://www.tone-doctor-llc.com/

Able Audio
Manufacturer of speaker rings, subwoofer enclosures, and templates. USA.
http://www.able-audio.com

Danish Sound Technology
Manufacturer of Vifa, Peerless, Logic and Scan-Peek speaker components and sound panels.
http://www.tymphany.com/

WeberVST
Amplifiers and speakers parts, audio components. Provides guide, information, reviews and industry news.
http://www.tedweber.com

Sonic Design
Provides accessories and software for loudspeakers and loudspeaker design. Sweden.
http://www.sonicdesign.se/

Component Plus USA
Makes components upgrades for tuners, digital audio and preamplifiers. USA.
http://www.componentplususa.com/

Musical Concepts
Makes and distributes hi-end audio components. USA.
http://www.musicalconcepts.com/