All systems go !
All systems go !
DRIVE UNITS BY MANUFACTURER:
Morel CAT 378 Tweeter
Categories: 0.75 - 2" (19-50mm) Dome Tweeters Morel Tweeters

The Morel CAT 378 is the modern updated replacement for the legendary MDT-37. This high efficiency horn loaded tweeter features a field replaceable hand coated 28mm Acuflex textile dome, a large ferrofluid cooled Hexatech aluminium voice coil, a vented ferrite magnet system and a tuned / damped rear chamber. This tweeter is ideal for low powered valve amps and has a detailed, unfatiguing sound with a gently downward sloping response - excellent for taming 'live' rooms with hard surfaces. Recommended frequency use: 2000-20,000 Hz. High power rating of 200w nominal, 1000w peak.
A full datasheet can be downloaded from the bottom of this page.
| Resonant frequency (fs) | 700 Hz | Nominal impedance (Zn) | 8 Ω |
| Effective diaphragm diameter | 28mm | DC resistance (Re) | 5.2 Ω |
| Ferrofluid ? Y/N | Yes | RMS power handling | 200W |
| Recommended crossover | 2khz | Faceplate diameter | 94mm |
| Sensitivity (2.83V/1m) | 93 dB | Cutout hole diameter | 72 mm |
CAT378
Not a review of the drive units received as such, because the project is still awaiting other parts from elsewhere, but the tweeters arrived rapidly and in good condition, as usual from Willys.
However, FWIW, based on previous experience with Morel tweeters, and having heard the design I'll be including these in, I would also recommend Morel tweeters. Not necessarily the very highest resolution, but still good clarity, and very easy on the ears. Good power handling too, and easy to replace the diaphrams if the worst happens.
Thanks for the review John !
Will & Caroline
Excellent customer service and good prices.
Thanks for the review Simon !
Will & Caroline
Friendly technical support
40+ years in the trade
UK family run business
Excellent customer service
Quick dispatch
Product as described, easy to cut & fit.
On reflection having now fitted the foam, I wish it was 15mm to 18mm or even 20mm thick. This is not a complaint. For a small speaker under 30cm high it’s perfect. For a larger speaker I feel a thicker sponge would hold its structure more pleasingly, its aesthetics, but important for the finished look.
I’ve been building my own home cinema as a complete DIY project and reached the stage where I needed some decent acoustic foam for my speaker panels (also DIY!) so I picked up 3 large sheets from here. They were sent quickly, packed well and moreover, are of excellent quality. With them being folded into the shipping box they were slightly creased but after leaving them out overnight on a flat surface, the creases fell out completely. They’re now in place and doing their job brilliantly. Cheers Willys Hifi!
The crossover was constructed well, I just need to figure out the best way to attach it to my Kef Concertos as they are bigger than the ones supplied by Kef that are mounted on the front of the baffle board.
Very nice deep bass look amazing with my custom made speaker
Great speedy delivery and very easy to fit. The plastic in my drivers had perished and they had suffered one too many parties! No need to make any adjustments (someone above did suggest that). I just screwed them in and the foam compressed into place. Before and after below (before I changed speaker number 2). Thank you!
