Methods of reducing driver temperature

Doesn’t anyone ever use internet search engines? It is not as though no-one has ever thought about this before. There are numerous articles and papers available discussing the measurement and computer simulation of voice coil temperature and thermal compression, as well as methods to improve cooling, so it should be easy to find some useful information on the topic.

Here are a few, in no particular order, to start with:

M. R. Gander, "Dynamic Linearity and Power Compression in Moving·Coil Loudspeakers”

J. Eargle, "Dynamic Compression in Studio Monitor Loudspeakers"

C. A. Henricksen, " Heat-Transfer Mechanisms in Loudspeakers: Analysis, Measurement, and Design"

T. S. Hsu & K. A. Poornima, “Temperature Prediction of a Voice Coil of a Moving Coil Loudspeaker by Computer Simulation”

A. J Hill, “Voice coil temperature in loudspeaker performance: Causes, effects and prevention techniques”

D. J. Button, “Heat Dissipation and Power Compression in Loudspeakers”

R. Bortoni, “Real-Time Voice-Coil Temperature and Cone Displacement Control of Loudspeakers”

The other factor to consider is the mechanical limitations of the drive unit. Assuming an effective, practical method to cool the voice coil can be implemented, how much more output will be obtained before excessive cone/coil movement becomes the limiting factor? At greater amplitudes, the cone suspension becomes less linear, and the coil may start to move outside the magnetic field. So, if the drive unit designer has optimised all parameters to limit at about the same time, improving the performance of just one won’t help much.

Before cutting holes in any panels, be aware that that the enclosure volume behind the drive unit may have been optimised for maximum power transfer; look up reactance annulling. It may have not, you would need to ask the designer of the cabinet, but be aware that attempting to vent the enclosure might result in greater losses than gains. You could always try it with the cover removed, which would make it a front-rear loaded horn.

if you have the time, money and inclination, go for it, but at least do some research on what has been done before, and understand the consequences of any changes that you make.

p.s. Some of the above papers are published by the AES. If you search for them the top results take you to the AES site, where they will be very happy to relieve you of your hard-earned cash in exchange for a copy. Move on. Many papers are available from the author, or the company they work for, free of charge. Anyone with access to a college library will probably be able to get them there.