Morel cat378 plus rs180p........

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MTM centers are indeed a compromise as most want to limit the height of the speaker. All MTM’s will not be optimum when utilized as centers unless they were specifically designed to do so, such as the Slapshot. There is little compromise using the Slapshot as a center unless one is sitting far off the lateral axis. This is true of course for any MTM center and worse for some than others. In my experience, the Slapshots will perform better off axis than many commercial MTM center channel designs, who seem to care little about fidelity.

If one has room for at vertical orientation on the center speaker the TMM certainly be acceptable, and of course will provide better lateral off axis response at the expense of some vertical axis issues, -although these are less important as the vertical listening angle range is generally less.

Due to driver placement on the front baffle, most MTM designs will require a slightly different crossover to be utilized in a TMM configuration. Of course this will depend on the design in question. No universal rule of thumb statement concerning making MTM’s into TMM’s or vice versa will apply in all cases. In some cases yes, in other cases, it will depend on how close to optimum you want the speaker to remain. They will all reproduce music, some with more aberrations than others. If one isn’t to concerned about absolute fidelity, one can certainly do as one pleases and live with the results.
If an MTM design was not well optimized initially, then there is a slim chance it might even sound better as a TMM. If this happens, one should immediately also purchase a lottery ticket. It would be a shame to let all that good fortune go to waste…
 
Chinook using a baffle step inductor ?

usually doesn't work too well with the increasing Z in a woofer.

I keep coming back to that morel, for years wanting to do something with it.

I'm more and more happy with the klipsch rb 75 I've been playing with (foam around horn mouth), I just suspect that I can have even less reflections with foam around the morel.

Slapshot (to me) is a risk as resale value is low and demand is even lower were I to build it.
But I suppose allowance needs to somewhere, right ?
We are on diyaudio..................

I'll read and chew on your post.
 
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the tweeter crossover seems bizarre.

A stock morel cat 378 has a bit of lift from 2khz-7khz due to the shallow horn loading.
They show a chart where they add a 5.6uF in series.
Morel CAT378 Horn Tweeter
Basically the Z is around 6ohms (somewhat), so the pole should be 4.7khz, but the shallow horn loading makes the F6 at 2khz.

Now the slapshot design puts a 4.5ohm in series with a larger 8.2uF cap, making a pole of near 1.8khz.
To me the tweet would have a hump in the response.

Am I off base ?
crossovers aren't a strong suit for me.

Norman
 
hope that tweet is a good one as broke down & ordered 1 - used to compression driver on a K-tube which is very good. Will it fry or distort like hell with 5.6uF highpass ? I remember D28 cap highpass being somewhat "spitty" and that was with a D52 below it.
 
Don't feel bad, I'm like this close to ordering one and parts for various 6db crossover parts (attenuation then diff value cap needed).

Morel's freq chart looks real flat with the 5.6uF.
Got to cross that high to flatten out horn loading and knocked down before 14ohm 700hz resonance.

Newer b102 seems close in spl, notch out that 2,700hz resonance though.
Maybe use single inductor on it too.

I'm not expecting horn dynamics.
I am expecting most detail or the least reflections.
Many many monitors are doing the horn loaded dome thing, so there has to be something with it.
Foam around it would improve it even more.

A loaned dayton horn loaded dome (nd25fw-4) was magical crossed actively to a sf 6.5" at arms length, can't remember xover point.
Passively the dayton would be tricky with 1.7khz resonance.
 
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it might have enough dynamics near-field. D28 (flat front plate) spat a bit in whatever model Audio Concepts box I had with D52 and Dynaudio 12 (could have been a recording problem - does "Aerial Boundaries" CD have rough "transients"?) Foam on the front would help.

my next speaker after the horns - will probably be another Karlson with a K-tube tweeter. I need the impact plus clarity in the highs. But on the horn side, it might be fun to get a Sentry IV going again using 511 as midhorn. The Klipschorn despite problems, sounds a lot "prettier" on " A Gringo Like Me" than current B102 and APT150 - maybe I'll get those two to mesh a bit better. Khorn with K400/K55V and K77 way out in front, gives a very reverberant presentation of "Gringo" - lush with depth - B102 + APT150 sounds dry, unpleasant. I might be one of the few on earth who hears some good in the K400.

(I need a fridge and water leak fixed worse than a dome w. short "horn")
 
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hi Zvu - would you have values for that notch filter ? i want it to sound reasonably good and not "pop" the tweeter's coil.

nGgmN6D.jpg
 
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an online calculator suggests:

I have a steel core 1mH coil and motor run 40uF cap - plus small caps to tweak - if i go air core on the inductor, what's a reasonable gauge for the wire?


Resonant Frequency Fs 700 Hz
Nominal Impedance Z 8Ω
DC Resistance Re 5.2Ω
Voice Coil Inductance @ 1KHz LBM 0.09mH

jZpkQ2M.gif
 
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