I've been writing an explanation for our site - here's a first draft:
Retro10 - why is the 10CR250 ferrite?
The first reason is TONE. Not better tone but different tone. This is a contentious issue because ever since lightweight neo drivers appeared on the bass guitar scene there have been naysayers insisting that they can't produce the heavy or weighty bass sound that heavy ferrite drivers can. However, neo drivers are actually better at producing a big clean uncoloured tone because a neo magnet has a much more stable magnetic field.
The field created by ceramic (ferrite) magnet changes shape and intensity in reaction to the current flowing through the voicecoil - this generates a certain amount of midrange distortion, reducing the resolution and adding a distinct tonal character particularly at higher SPL.
If you spend enough money on a ferrite driver, using a cast alloy frame, adding copper and/or aluminium shorting rings and using a particularly huge magnet so you can saturate the pole pieces then, in theory, you could get a ferrite driver to sound just like a neo driver (although in practice the huge difference in magnet size and thus woofer basket shape changes the acoustic behaviour of the reflected back wave).
If we want to make an old school sounding driver then we feel that the distortions inherent to typical ferrite magnets are an important part of the tone.
The second reason is output. We wanted to create a driver with significantly more excursion than those in the '69er. This required a frame and magnet structure with the room to let a long voice coil move back and forth a long way and the only such 10" neo structures available have very large diameter voice coils which would restrict the high frequency extension and also its dispersion. So to get the big output in the lows and the tone in the highs we needed a ferrite driver.
We could have created a 10" neo driver for the Retro Six10 but it wouldn't have had such an old school character in the mids and little more than half the max output in the lows. Yes, it would have brought the weight down from the '69er's by about 6lbs but the cab is already very light for its size, especially as we've had customers question the stability with a heavy valve amp on top. The neodymium would also have increased the component cost further (noting that the 10CR250 drivers in the Retro Six10 are a step above those in the '69er), so we'd have had to raise the price much more.
When we at Barefaced state our goals are:
Maximum tone
Maximum output
Minimum weight
we mean it in that order. Get the tone and output we want. Then make the cab as light as possible without affecting the tone and output whilst ensuring it remains gig tough and reliable with a very long working life.
For the Retro10 series the only way to hit the tone and output goals was with ferrite drivers - they're still lightweight cabs though!
