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Morel CAT 378 1-1/8" Soft Dome Horn Tweeter

Brand:|Model: CAT 378|Part # 277-084
Morel's CAT378 features a hand treated 1-1/8" soft dome, horn loaded for higher efficiency and high dynamic range without power compression.
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List Price$87.99
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Part # 277-084
  • 94 mm horn-loading faceplate
  • Large Hexatech™ aluminum voice coil
  • Replaceable Acuflex™ dome/coil assembly
  • High sensitivity
  • High power handling
  • Sturdy gold plated input tags

Product Details

Morel CAT 378 1-1/8" Soft Dome Horn Tweeter

Morel's CAT378 features a hand treated 1-1/8" soft dome, horn loaded for higher efficiency and high dynamic range without power compression. The magnet assembly is vented into a damped rear chamber to lower resonance and to eliminate "honking" at lower frequencies. Latest evolution of the popular MDT-37 tweeter. Replacement diaphragm (277-046).

Product Specifications
  • Tweeter TypeSoft Dome
  • Cone / Dome Diameter1-1/8"
  • Impedance8 ohms
  • Power Handling (RMS)200 Watts
  • Frequency Response1,800 to 20,000 Hz
  • Sensitivity93 dB 1W/1m
Thiele-Small Parameters
  • Resonant Frequency (Fs)700 Hz
  • DC Resistance (Re)5.20 ohms
Mounting Information
  • Overall Outside Diameter3.70"
  • Cutout Diameter2.83"
  • Depth2.32"
Morel CAT 378 1-1/8" Soft Dome Horn Tweeter
  • BrandMorel
  • ModelCAT 378
  • Part Number277-084
  • UPC844632070761
  • Product CategoryTweeters
  • Unit of MeasureEA
  • Product Rating
    (14 Reviews)
  • Weight1.45 lbs.
  • California Prop 65

    Warning: California residents only. Please note per Proposition 65 that this product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

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Morel CAT 378 1-1/8" Soft Dome Horn Tweeter
Morel CAT 378 1-1/8" Soft Dome Horn Tweeter is rated 4.8571 out of 5 by 14.
Rated 5 out of 5 by from Great Design EffortThe folks at Morel have captured a robust design, with high power handling and in this tweeter's case, a horn-type sound that helps a tad with timing and has a good dispersion...Great ergonomics and a tight, flush fit. The heavy weight construction avoids vibration and buzzing from high volume and heavy bass.These tweeters can be loud and in cases need to reduce volume to match bass. That can likely be tamed by using resistors, a parametric eq or an active crossover system if one can afford that route...
Date published: 2013-09-20
Rated 5 out of 5 by from Perfect, if you know how to tame itMorel goes out of their way to show with a simple 6dB crossover, this tweeter delivers a flat response that easily blends with a woofer.With some extra effort it's even nicer. This tweeter is efficient and usually requires a resistor to pad it down. I put a 0.5 to 1.5 uF capacitor in parallel with the resistor, which brings out the very highest frequencies above 15K, giving an "etched" quality to the highs, somewhat compensating for the midrange emphasis of the horn.I matched it to a MW266 woofer with tweeter below the woofer. In situ, the tweeter is slightly off axis from the listener position and the capacitor makes up for it.The CAT378 is a descendant of the classic Dynaudio D28 and Morel MDT28. It has dynamic range to burn, tremendous clarity, and does well with 6db crossovers and as low as 2000Hz crossover point. The horn is good for time alignment - which is more important than most people give it credit for.I recommend going out of your way to flush mount this tweeter so there are no edges or discontinuities. Router the hole so the flange sits flush with the box. Mount the tweeter off center so distance from center to each cabinet edge is different, which will dilute diffraction effects. Round the edges of the box if at all possible. I put a 6" felt diffraction ring around it too. The extra attention to detail gives extraordinarily smooth response and resolution.I've included a graph of the response I achieved with the Morel MW266.
Date published: 2013-04-29
Rated 4 out of 5 by from Quite simply...Nice.I ordered a pair of these and put them through the usual testing that I always do when I buy new speakers; I listen to them all alone, I listen to them in a two way bookshelf test speaker system, and this time I even put them in my car (OEM dash location in a Dodge Magnum). All around they performed well. They were louder than many I have used, but managed to sound smooth and very clear. I plan on leaving them in my car even though that was not their intended destination-but if you need a loud tweeter that sounds good, these are great.
Date published: 2011-09-29
Rated 5 out of 5 by from It's A Hard Tweeter To BeatThis tweeter is always my first pick for new builds it can be crossed over low in 2-way system if needed as I do in a WTW @1600Hz 24db LR roll off and it works great and still sounds good evevn at high power levels I got it on a Crown XLS 1000 DriveCore amp and I push it all the time as it is a part of a work speaker and I don't give no mercy. This tweeter makes for a great high out tweeter for poeple that like it loud but still like it to sound good and for me there is no other way yes I have some nice big P.A speakers but the highs still don't sound as smooth as this tweeter but this tweeter don't go as loud. I use this tweeter in a high powered house-party 3-way speaker as well. I cross it over @2500Hz 12db LR along with the other drivers it sounds much better then pulling out the P.A speakers I still use the P.A subs. I have a hard time not going with this tweeter the high sensitivity, power handing and good looks make it hard to beat for the money I highly recommend it.
Date published: 2011-01-15
Rated 5 out of 5 by from MorelOutstanding product ,,I've used these tweeters on most of my projects and when I used other tweets ,I wound up going back to this tweeter ,in the right cabinet set up and cross over it is amazing what you'll hear ..
Date published: 2010-10-05
Rated 4 out of 5 by from Great tweeter used rightIn two projects I've used first the CAT408 and second the CAT378, and overall I like the CAT408 by a small amount. If you need to have the tweeter timed later than a small woofer (my needs), the CAT378 really fits the bill. I highly recommend this driver for almost any project.
Date published: 2010-08-06
Rated 5 out of 5 by from Louder than the older MDT-37!I through a pair of these newer CAT-378's in some cabinets that previously had the older MDT-37's. I measured these to be a little bit smoother in their response. I also found these to be 1 db louder than the MDT-37's. I now need to add 1 db Pads for designs I made using the older MDT-37 drivers. According to Morel the CAT-378's have a higher grade magnet. I am wondering if this is making them a little louder / efficient. I did not know this when I wrote a previous review.
Date published: 2010-03-30
Rated 5 out of 5 by from Good & Wide Sound - Great for Time Alignment!I bought this and mated it to the B&C PS100 with a 24 db / octave LR crossover at 1,320 Hz. Part of the reason for the LR crossover and choosing this driver was to ensure both drivers are in phase with each other at all frequencies. This driver is a shallow horn loaded design. (By surface mounting my B&C PS100 and mounting the face of the CAT378 flush with the cabinet surface, it results in approximately 1mm difference between the two drivers domes for near perfect alignment.) This makes time and phase alignment with this driver by using a LR crossovers in 2-way designs really quite easy. The only RTA measurements I've taken to date in my living room at about 40" away have been very encouraging. In this location with my speaker system design it is +/- 2.5 db from 1.81 - 18.25 kHz in 1/24th octave resolution using TrueRTA software. (I had expected it to be overall strongest in the 3.5 kHz range but found it to actually be in the 8 - 10 kHz for both of my drivers in both speaker locations. Overall it was a more neutral sounding response than I expected based on seeing Morels graphs on their website. A Plus!) I find this driver to sound bigger than it is. In listening I don't think it sounds like the sound is originating from a 1" wide source. Maybe that is because of the shallow horn design. This bigger sound helps make stereo imaging very smooth, very big and wide. (Regardless of the reason it is a definite plus in my book.)Available replacement Domes are a definite plus should you ever accidentally hit play with a powerful amp left in the max position from repair and take out your tweet's. (Speaking from experience, it only takes two snare hits.) They are easy to change on this model and cost much less than completely new drivers.I highly recommend my B&C PS100 / Morel CAT378 / 1.32 kHz. 24 db/octave LR crossover setup. Nice Driver Morel. I'll be using it in my next speaker design as well. Thanks!
Date published: 2010-01-10
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Morel CAT 378 1-1/8" Soft Dome Horn Tweeter

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