WHAT IS PASSIVE BASS?
A passive radiator speaker is a simple device that increases the low frequency response (Bass) of a speaker system.
In a nutshell, when used properly, a passive radiator will give a speaker system the comparable performance characteristics of a much larger system.
A lot of air needs to be moved in order to produce audible bass frequencies. Traditionally, when it comes to bass production, a larger woofer meant louder, clearer bass.
PASSIVE RADIATOR TECHNOLOGY HAS BROKEN THIS TRADITION.
WHAT IS A PASSIVE RADIATOR?
A passive radiator looks like a normal driver (speaker) from the front, but on the backside, it appears to have had all of its components removed. A passive radiator is a speaker without the magnet and electronic structure attached to it. It is just the cone, suspension, and frame.
A passive radiator is a reactionary device. Normally, when a driver (such as a subwoofer) is mounted to a sealed speaker box (enclosure), the physical forward/back movement of the speaker affects the internal air pressure of the enclosure. When a passive radiator is mounted to the same speaker box, the internal air pressure fluctuations (caused by the movement of the driving speaker) causes the passive radiator to begin moving forward/back as if it was also a driven speaker. When the passive radiator moves, it creates sound frequencies just as a normal driver does.
ADVANTAGES OF PASSIVE RADIATORS
Passive radiators allow woofers to produce deep tones that otherwise may not have been possible. Depending on the tuning when incorporated, a passive radiator will start to move as the drive woofer begins to produce lower frequencies. By engaging at this point, the passive radiator absorbs energy from the drive woofer thus reducing the drive woofer’s motion (we call this dampening). Since the drive woofer is now moving less, there is less risk of damage occurring due to over excursion (speaker moves so far it breaks). There are 3 main advantages here:
1. The motion of the drive woofer is dampened thus flattening the frequency response; this makes for smooth sound reproduction.
2. Passive radiator systems can have the same sonic output as larger speaker cabinets, but in a much smaller size.
3. Use with any Bluetooth device. Have no barriers between you and the music you want to hear.
To put it succinctly, when a passive radiator is tuned properly it can greatly enhance the sonic capabilities of a speaker’s low frequency production.