Engineers at PRV Audio have worked hard to bring you a reliable line of components to fit any audio application. They also like helping you choose the correct component for your custom built enclosures or finding replacements for blown loudspeakers.
With this, PRV audio offers Speaker Basics to help consumers further understand parts, specifications and parameters so that you may make the best decision when buying your next PRV Audio Loudspeaker.
There is very little published information regarding compression drivers, also known as HF (high frequency) drivers. Below you will find some basic FAQs for compression drivers and if you want more detailed information check out the entire description for Parts of a Compression Driver and Compression Driver Specifications.
Q. What is a diaphragm?
A. A compression driver’s diaphragm is comparable to a woofer’s cone in that it moves air to create sound. The diaphragm is attached directly to a voice coil, which interacts with the driver’s magnet and moves when an AC signal from an amplifier is applied. Check out “Parts of a compression driver” for more details.
Q. What is the standard mounting for a driver?
A. Compression drivers feature one of four methods for connecting the compression driver to a horn or waveguide. 1″ models are designed for 3 different applications. 1 3/8″ screw-on (or spin-on) for most 1″ exit models and 2 or 3 bolt for bolt-on applicaitons. 2″ exit drivers have a 4 bolt configuration. All PRV Drivers use M6 bolts. Check out “Parts of a compression driver” for more details.
Q. What is a phase plug?
A. Most compression drivers are built with an internal phase plug of a radial design (slits that are similar to lines on a compass) or a concentric ring design (similar to that found on a shooting target, and also called an annular design).
When used, phase plugs serve to combine the output from the different areas of the diaphragm into a single output, for a more seamless transition from a compression driver’s diaphragm to its exit.
Q. How does PRV Test Sensitivity?
A. PRV Audio sensitivity specifications are given at 2.83 volts AC, measured at 1 meter. This allows for a true, driver-to-driver comparison for matching every driver we make to one-another, regardless of nominal impedance. Check out “Compression Driver Specs” for more details.
Q. What affect does the diaphragm material have on the sound?
A. The diaphragm is made of different materials for different applications. A composite phenolic diaphragm is typically used in midrange applications where smooth vocal reproduction is required, such as in public address stadium horns. A titanium diaphragm is typically used in applications where high frequency response is required, such as in two-way and three-way speakers. The diaphragm is made of different materials for different applications. Check out “Parts of a compression driver” for more details and other materials.
Q. What is the difference between “Throat” and “Exit”?
A. These terms are interchangeable. The exit is the opening in the compression driver through which sound moves from the diaphragm, to the throat of the horn.
For the best possible sound, match a horn or waveguide with the same throat entry diameter to the exit of the compression driver. Mismatching horns with compression drivers results in reflections that reduce high frequency output.
Q. What is the difference between RMS Power and Musical Program Power?
A. RMS is also called continuous power, this power handling rating is determined using a pure, constant signal (according to EIA 426A) and amplifier capable of delivering constant power for eight hours.
Musical Program Power – Music content, when viewed as signal provided to an amplifier, is much different than the pure, constant signal used to determine RMS power handling.
Music has within it many quiet passages and periods of inactivity and transition. Though measured in milliseconds, these small breaks in the action allow for cooling to take place as the amplifier power sent to the compression driver drops to nearly 0 watts.
Though used by other manufacturers as means to inflate power handling, our active partnerships with end-users and OEMs world-wide, in high SPL applications, gives you the real-world confidence you need, to know that your PRV Audio driver will live up to your expectations.
Q. Do I have to stick to the miniumum crossover recommendation?
A. PRV Audio’s minimum crossover point recommendation. This is listed to give you a baseline crossover point to limit the compression driver’s exposure to damage. Check out “Compression Driver Specs” for more details
Q. What is Inductance?
A. A voice coil’s resistance to high frequency. Inductance, measured in milliHenrys, is a by-product of a voice coil’s windings. The voice coil, wound on a voice coil former, naturally forms an inductor that resists high frequency reproduction by acting as an electro-magnetic brake, resisting the rapid change in motion (also called energy storage) needed for high frequency response.
PRV Audio compression drivers feature some of the lowest inductance measurements in the industry—the D4260 series drivers’ motors have less than 0.20 mH inductance—for the fastest transient responses, and highest frequency responses available.
Q. Why does “Flux Density” matter to me?
A. The measure of how much strength a magnetic motor system contains. The higher this figure is (measured in Teslas, T) the better it is seen to be. A high flux density compression driver motor generates higher sensitivity and lower distortion than a comparable compression driver with lower flux density.
Q. Does magnet material matter
A. Magnet material iIndicates the type of material used in the permanent magnet. Ferrite (also known as ceramic-ferrite) permanent magnet systems are larger than similarly charged neodymium permanent magnet systems, but are less susceptible to heat damage and are more weather-resistant.