The Scan-speak R2904-700000 tweeter is the new flagship tweeter in the Scan-speak line. This tweeter incorporates many innovative design concepts.
The first notable difference is the use of a phase plug. The dome is attached to the phase plug, so the radiating area is now concentrated around the voice coil. This offers more control and reduces distortion and loss that occur at the center of the dome on dome tweeters. The phase plug also acts as a wave guide, reducing high frequency cancellations. A specially designed venting system uses a needle to cut down on turbulence in the air cavity. Better dynamics are achieved by not using ferrofluid, voice coil cooling is performed by the venting system and conduction through copper rings. The new SD-2 neodymium magnet system improves transient response.