Vendor guidelines - Morel:

Morel's line of woofer and mid/bass units deserve further comment. Traditionally, Morel's LF drivers tended to high Q's and low sensitivity. These drivers worked best in sealed enclosures. Recently, Morel introduced their new "Neolin" line of drivers. Once you get past the hype to the specs, you realize that the main difference in the Neolin line is that they're much better suited to vented systems.

As a final note, in addition to explicitly shielded drivers, all of Morel's double magnet, non-Neolin drivers feature very low stray magnetic fields and can therefore usually be used in applications usually requiring a shielded driver.

In 2003, a feud broke out between Morel USA, and its parent company in Israel. The confusing result of this is that the two separate companies have established separate distribution channels, each using the Morel name. The good news is that all of the classic Morel drivers are available from both company's distributors. The bad news is that all of the newer drivers are proprietary to one or the other and are therefore only carried by that company's distributors. To date, I have primarily received recommendations for the classic Morel designs, with the exception of the two new Supreme tweeters.

Standouts among Morel's designs include:

1. The MDT33 tweeter has a very devoted following. It features include a sophisticated double magnet design and back chamber, plus lots of attention to linearity. Those who recommend it also point out its ability to cleanly handle prodigious amounts of power as well as its low end extension which allows crossovers as low as 1.4 kHz. Some have also recommended the use of a Zobel to sweeten the top end.  view   response   waterfall 

   Note:	The MDT33, laong with the Accuton C223/6, Hiquphon OW I/II/III, Human 002, Scan-Speak R2904/7000, and the Alison Acoustics 4010203 (available only as a replacement part for Allison loudspeakers) are considered by many to be the ultimate electrodynamic tweeters.

2. The Supreme 110 tweeter is the new sucessor to the venerable MDT33 from Morel/Israel. Featuring a neodymium magnet and an underhung motor (a rarity in a tweeter) for lower distortion, and using a large diameter VC and coated textile dome, it shares most of the MDT33's characteristic virtues, but is roughly 1 dB less sensitive. Although not shielded, its neodymium magnet also produces less stray magnetic field than the MDT33. Reports put it in the top echelon of currently available conventional tweeters, while still costing only about 15% more than the MDT33. All Supreme 110's are packaged as matched pairs.  view   response   waterfall   impedance   phase 
3. The Supreme 130 tweeter is an interesting variant of the Supreme 110, described above. It features a larger diameter face plate than the Supreme 110 (130 mm vs.110 mm). This allows the actual driver to mounted off-center in the faceplate. This neatly solves the problem of mounting the tweeter as closely as possible to the midrange or mid/bass driver without resorting to a square or rectangular face plate with all the mounting problems that entails. The Supreme 130, selling at nearly $100 more per pair than the Supreme 110 is targeted at the extreme high end. As with the Supreme 110, the Supreme 130 comes only in matched pairs, but with individual performance documentation.  view   response   waterfall   impedance   phase 
4. The MDT30, DMS30, and MDT32 tweeters are all lower-cost single-magnet alternatives to the MDT33. The principle differences between the models is that the face plate of the MDT30 is 94 mm (3.7") in diameter, while the MD32 is larger at 110 mm (4.3") in diameter. Magnetically shielded versions of the MDT30 and MDT32, called the DMS30 and DMS32, respectively, are available for use in home theater applications. Most of the MDT33 performance comments apply to these drivers except that these are 2.5 dB less sensitive than the MDT33.  MDT30/MDT32 view   MDT30/MDT32 response   MDT30/MDT32 waterfall 
    DMS30 view 
    DMS32 view 
5. The MDT39 and MDT40 tweeters are, in most respects identical to the MDT30/32 tweeters. Their primary differences are their diminutive 54 mm (2-1/8") square face plate. One of the side effects of the reduced size is reduced continuous power handling and lower sensitivity ( 1 dB for the MDT40, 3 dB for the MDT39) compared to the MDT30/32 drivers. The MDT39 and MDT40 are shielded for use in home theater applications. Aside from sensitivity, the principle difference between the two is the MDT39's slightly cleaner FR and waterfall plots.  MDT39 view   MDT39 response   MDT39 waterfall 
    MDT40 view   MDT40 response   MDT40 waterfall 
6. The MDT37 is a semi-horn loaded tweeter which features excellent sound as well as 93 dB sensitivity. It shares all of the other Morel tweeter virtues, meaning it's one of the cleanest sounding high-sensitivity tweeters you can find. A shielded version, the DMS37, is also available.  MDT37 view   MDT37 response   MDT37 waterfall 
   
7. The MDT20 is Morel's idea of a low-cost tweeter. Featuring a plastic face plate, but with more expensive features such as a rear chamber and ferrofluid, it's somewhat more expensive than other low-cost tweeters, but features all of Morel's traditional tweeter qualities - high power handling, low distortion, silky smoothness, and great sound.  view   response   waterfall 
8. The MDT22 tweeter is an alternative implementation of the MDT20 low-cost tweeter goal. This time, Morel used a very small face plate with a neodymium motor to create an attractive shielded driver. Because of the geometry, a minor glitch in the MDT-20's response around 15 kHz is magnified in the MDT-22. All other MDT-20 comments apply.  view   response   waterfall 
9. The MDT41 tweeter is an externally mounted version of the MDT40. Offering the same high level of performance as the MDT40, the MDT41 includes a convenient and easy to install mounting kit.  view   response   waterfall 
10. The MDM55 2" soft dome midrange is a descendent to their well-regarded MDM85 unit. One of the few dome midrange units which actually deliver on their promise, the MDT55 features extremely flat response with good extension and well controlled roll off at both ends of its passband. As with all Morel drivers, it can handle lots of power without damage or distress and can tolerate low order crossovers. One user reported excellent results using a set of MDM55's to replace the original Vifa midrange drivers in a Dunlavy SC-V system.  view   response   waterfall 
11. The MW114-S 4" dual magnet, damped polymer composite (DPC) coned midrange (called a woofer by Morel) offers smooth, extended response along with an exceptionally high Xmax for a 4" driver. This uses their latest neodymium magnet technology and features a high ratio of VC-to-cone diameter.  view   response   waterfall 
12. The MW142 5" dual magnet, damped polymer composite (DPC) coned mid/bass offers smooth, extended response, albeit with a small plateau between 1-3 kHz.The MW142 uses Morel's dual magnet technology and features a high ratio of VC-to-cone diameter. As noted, Morel licenses much of its technology from Dynaudio and the MW142 is Morel's version of the venerable Dynaudio 15W-75.  view   response   impedance 
13. Morel makes three 6" DPC mid/bass drivers. All feature a large 3" diameter VC, and all have similar performance, varying in specific details. All have been recommended.
    1. The MW166 double magnet driver has a notably smooth FR. This is a classic Morel design, featuring high Qts, low Vas, 86 dB/W/m sensitivity, and a higher Fs then the following drivers. Notably, it has a large 4.25 mm Xmax.  view   response   waterfall 
    2. The MW167 Neolin motor (see below) driver also has the 4.25 mm Xmax of the MW166, but features a lower values of Qts and Fs, with a higher Vas and 88 dB sensitivity. Its FR curve is not as flat as the MW166's, having a slight rising tilt.  view 
    3. The MW168 double magnet driver (a standard Morel driver, but only Madisound advertises it) is similar to the MW167 in having lower Qts and Fs than the MW166, higher Vas, and 88 dB/W/m sensitivity, but Xmax is only 3.5 mm. As with the MW166, it's FR is slightly better than the MW167.  view 

14. The MW267 is an 8" neodymium magnet woofer, also using Morel's latest Neolin motor and construction technology. Like all Morel woofers, it's a good performer with good curves, numbers, and notable power handling and linearity. Unlike other Morel woofers, this lower-Q, higher compliance design is one of the first using their new "Neolin" technology.  view   response 
15. The MW1077 is a 10" woofer using Neolin technology. This relatively high-Q driver would work quite well in a sealed or transmission line enclosure. Although Fs could be lower and Xmax could be higher, the FR curve is commendably flat throughout its operating range.  view   response 
16. The MW1075 is a double magnet 10" woofer with DPC cone. Although not quite the match for the MW1077 in most respects, it's one of the few 10" drivers with a low enough external magnetic field to be used near TV's or monitors.  view 

New drivers to watch for from Morel/USA are all designated as the "Shabani" series, after Mikhael Shabani, Morel/USA's founder and chief designer. As with Morel/Israel, I haven't received sufficient feedback to recommend these yet, but the Shabani line includes:

• There is a single 1.1" (28 mm) soft dome tweeter which doesn't appear to break any new technical ground. Presumably, it will still share Morel's excellent reputation for tweeters.
• The MSD56 soft dome midrange looks less like the MDM55 and more like an oversized tweeter. Featuring a commandably high Xmax value (over twice that of the MDM55), this could be interesting for those wanting to use a dome midrange.
• The new Shabani series woofers and mid/bass driver appear to be fairly conventional for Morel - moderate to fairly high Qts values and decent but hardly extreme Xmax numbers. In a significant break with Morel tradition, they all feature cast aluminum frames.
• The Shabani MSW-12.1 subwoofer breaks with Morel tradition in most respects. Although hardly state-of-the-art, its Xamx is significantly higher than we've come to expect from Morel. Its Qts value is quite low, and it's built on a cast aluminum frame.