Morel 536/8 series Junk?

ShaneF

Member
2015-12-02 4:42 pm
I have been looking at the CAW / EW / ECW 536 series of drivers. I have noticed that the cheapest (CAW536) has the most reasonable response curve, and thereby, less of a fortune spent on the crossover. The other two are significantly more expensive because of superior parts (apparently). Having said that, I have heard some pretty bad press about them... miserable distortion.

Have any of you experienced this? If you were left to your decision about these 3 drivers, which would you choose? At the moment, the cheapest one seems to be the best because the response curve isn't as much of a mess.

What are your opinions?

Morel CAW 538 5" Cast Frame Woofer

Morel EW 536 5" Woofer

Morel ECW 536 Coppersleeve 5" Woofer
 

eriksquires

Member
2013-05-10 4:11 pm
Hi,

For the same price range, the 5" Scanspeak revelators are competitive, and may even get you a lower F3 but not the high power handling. Gravesen has a 2-way kit that uses Scanspeak 15W see his solution here. He measures a -3dB point of around 47 Hz. If you are doing a 2 way, those are much better options. If you are doing a 3-way or ported, then they are competitive solutions.

There are probably also competitive answers in the SB Acoustics line that a lot of DIYers rave about.

Best,

Erik

Given that I have the Scanspeak 18W versions in my two ways and love them, and have measured just how good the distortion is I'd go with those instead, but that's without direct experience comparing them.
 

ShaneF

Member
2015-12-02 4:42 pm
It's a 2-way in a box, in the house.

I looked at the scanspeak too. I am sure they are excellent. I am using a 7L box and I'm hoping to keep the crossover simple. There's lots of fun stuff in the stratosphere of the scanspeak that has to dealt with... yes?
 
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In the end, you just have to fancy having a go at a project.

Morel CAW 538 5" Cast Frame Woofer

The cheapest Morel 538 with simplest motor looks easy enough. 8L reflex with Qts 0.38 actually. But 7L is hardly a big change.

I suspect it will work well enough with a 4kHz crossover (3.3uF and 0.3mH and some resistors at a guess) to a second order tweeter. Maybe just a simple 1.5mH bass coil.

Maybe that big 3" rubber dustcap has some issues, but Morel don't build rubbish. Most people like them.
 

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eriksquires

Member
2013-05-10 4:11 pm
Shane, the Revalator's big advantage is the -3 dB point. However, are you stuck with the 5" or could you do 6.5? For about the same price you are in the range of the 18W/4531 wich higher power handling and an even better bass response than any of them. Crosses over very nicely around 2kHz and has better efficiency (90 dB).

Best,

Erik
 
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I think the CAW538 should be up to the task, and be a great sounding woofer. The coppersleeve models have SoTA HD curves, so I don't know what's not to like. The dustcaps are not rubber, and are a one-piece vacuum-formed magnesium silicate/DPC/talc-filled polypropylene. All are the same thing.

The Revelators are easily $50 more, slightly less sensitive, but likely have lower HD (at least for the CAW series, but the Revs are class-leading in the HD curves), and more Xmax.

I know the CAW634's I have are modeled to have an F3 of the lower 30 Hz range in 20 ltrs. Granted- this is the 6.25" and at almost 3x the volume. I think you'll be fine with your choice.

However- don't think you can take a xover from one speaker with your tweeter in that speaker, and change the woofer and get good results. xovers are like fingerprints- they only fit one particular system most times.

Later,
Wolf
 

wintermute

Administrator
2003-08-03 11:43 am
Sydney
Not sure whether you meant to say in the OP that the 538 has the nice-est response curve...

The 536 has a slightly higher efficiency and better x-max though which may be useful if you are not using them as a mid.

I've got the older generation MW-144's and I'm very happy with the sound (once I fixed some response anomalies which were exacerbated by my cabinet design).

They cleaned up a lot once I stopped running them as the main bass drivers though. They are now crossed at 270 Hz (4th order accoustic) to 10" woofers. This has improved them quite a bit.

I think that the 538 mated with a cat-378 tweeter would be an excellent combo. I suspect that they have probably kept the same formula as the MW-144 paired with the DMS-37. near perfect time alignment if the tweeter is flush mounted and the woofer surface mounted (which certainly helps with crossover design).

I made an MTM with the MW-144's in sealed 5L enclosures (5L per driver). The F3 is around 80 Hz. Not sure how they would go vented, but as I said, to really shine you don't want them playing much under 300Hz (though they were certainly very good even when I was running them without the 10" woofers, albeit a bit light on the bass).

edit another 5" that I think would be worthy of consideration (and is in the same price range) is the satori https://www.madisoundspeakerstore.c...8-5-egyptian-papyrus-cone-woofer-8-ohm/#tab-2

I've got some SB 4" midrange drivers and I am very impressed with them. Again these aren't going to give incredible bass, but we are talking about 5" drivers.....

Tony.
 
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TBH, I was rambling last night, so apologies to wolf_teeth for any remarks. But I still hate huge dustcaps. :)

But the 5" bass plus 1" tweeter has been done before. TBH, as Tony says, it's hardly going to touch the deep bass that we all love. What do you expect from 5" and 7L bass? :D

I had a look at various filters.

537280d1457924162-morel-536-8-series-junk-schematic.jpg


This one doesn't do it for me. An LR2 design works better, and red resistor is your tweeter level. Or the simpler bass coil and second order tweet used in the original KEF Cresta.
 

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