Super MWM

[parlophone1]

Thanks for the answers.

I knew that xilica is a professional tool but do not know how to interpret all the data avaliable for the crossover. Therefore, I was not aware of possible limitations especially regarding its in house usage.

[Dave A]

On 8/15/2019 at 6:07 AM, parlophone1 said:

How far back on super MWMs can the K402s be positioned in active setup to compensate for delays using Xilica or DBX active crossovers?

Moving the 402's back as far as possible would still leave you with 40 some inches displacement with these and then a reflecting surface for sound to bounce off of so the answer is you would not do this.

[Dave A]

On 8/15/2019 at 12:24 PM, babadono said:

@Chris A ? I would think using with a Xilica you could adjust delays such that you could place the 402 pretty much where ever on the Super MWM that you would like. Even to the point of some of the energy bouncing off the top of the bass cabinet instead of going out into the room (which is probably bad).

I have found that setting the 402's right at the front of the bass bin with a focal point behind me and not pointed right at me and a 6.35ms delay yields stellar results.

[Dave A]

On 8/15/2019 at 1:52 PM, Chris A said:

Commercial cinema loudspeakers must have sweet spots as large as the auditorium seating that they cover--eliminating the archaic audiophile need for "sweet spot listening".  The only limitation is stereo listening, whereby in order to get a balanced phantom center image, you must be sitting on centerline between the left and right loudspeaker arrays (which is a limitation of stereo recording and playback itself).  In multichannel soundtrack and music playback, loudspeakers designed for commercial cinema must make every seat in the house a viable listening position, locking in the center of the acoustic image using loudspeaker arrays of 5.1+ loudspeakers.

Even in two channel the sweet spot effect on these is much larger and sitting directly in front of either the left or right speaker set you can still get good opposing channel sound levels. The bigger the pro gear it seems to me the better you can hear this and it took the KPT-456's to begin to show me this and the MCM 1900's really did it well. What I did not realize was how unbalanced output was with amps even though the name plate said the same thing and channel to channel on the same amp is different too. These Xilicas helped out giving me complete gain control and this made another BIG improvement.

[ClaudeJ1]

On 7/21/2019 at 9:57 PM, Chief bonehead said:

This drawing shows quite the negative expansion rate at the “reflector”. As you plot the expansion you must keep a zero to positive expansion rate thru the turn. Otherwise it will produce some distortion. Just my two cents. 

This is the very reason why I chose my reflector carefully in my Quarter Pie, ignoring the "Edgar Graphic" suggested by JWC. I was happy with the sound and chose no further changes, so your post supports my decision. Thank you.

[parlophone1]

So, is the design of SMWMs finally done? Are the overall dimensions 60 by 60 inches as indicated in drawings from page 13?

If so, I believe will be able to squiz them in my living room. It would be tough but probably feasible.

My spouse is pretty flexible regarding my audio escapades, but in this case and given the dimensions of bass bins, I believe some extra effort from my side would have to be done if these will end up our house.

[Dave A]

5 hours ago, parlophone1 said:

So, is the design of SMWMs finally done? Are the overall dimensions 60 by 60 inches as indicated in drawings from page 13?

If so, I believe will be able to squiz them in my living room. It would be tough but probably feasible.

My spouse is pretty flexible regarding my audio escapades, but in this case and given the dimensions of bass bins, I believe some extra effort from my side would have to be done if these will end up our house.

Done and they have been built and in active use for months now. They are big and awesome sounding. Those are the plans. The only error on them is one of the 1" x 1" corner pieces is short and I never fixed it. All the rest is right.

 

[parlophone1]

Thanks.

[rosey]

Looks like I've got a new project. Haven't even finished the jubilee project!

[noviygera]

I have been using Peavey FH1. Is there a design in-between the FH1 (LaScala) and full blown MWM? 

The MWM is just too big for my space but I can definitely go larger than the FH1 to hopefully get 70-80hz horn

[moray james]

4 hours ago, noviygera said:

I have been using Peavey FH1. Is there a design in-between the FH1 (LaScala) and full blown MWM? 

The MWM is just too big for my space but I can definitely go larger than the FH1 to hopefully get 70-80hz horn

http://www.inlowsound.com/

[Dave A]

23 hours ago, moray james said:

http://www.inlowsound.com/

I have seen those plans and many others which can save a lot of space and dig much deeper. With every turn and bend I have to wonder what exactly it does to sound quality. I have no analytical tools or ability to measure such a thing so it is conjecture which leads me to believe the very best quality of sound will come from a good throat depth with minimal turns and severe restrictions.

[moray james]

14 hours ago, Dave A said:

I have seen those plans and many others which can save a lot of space and dig much deeper. With every turn and bend I have to wonder what exactly it does to sound quality. I have no analytical tools or ability to measure such a thing so it is conjecture which leads me to believe the very best quality of sound will come from a good throat depth with minimal turns and severe restrictions.

a straight horn is your best option provided you have the room. Find me a better horn for a given bulk this is the best I have found so far. wider bandwidth than a Jubilee and smoother response. folded horns when don right are your friend the folds help to filter out out high frequency which you do no not want coming out of a big bass horn to screw up the image.

[Marvel]

A Univerity Classic can get up to 1kHz... with fewer bends.

 

 

[moray james]

47 minutes ago, Marvel said:

A Univerity Classic can get up to 1kHz... with fewer bends.

 

 

that's true but you don't want to hear 1k coming out of a Classic in a home rig. That said both the classic and the dean (both by University) are two more of the very good bass horns out there.

The California designed by Ernst Georg Beck is an ideal bass horn for a two way because it has the necessary extension and a natural roll off this permits running a mid horn of reasonable proportions which was also the goal of the Jubilee by the way as the KHorn cannot get up high enough to make a two way with a reasonable size horn.

[Marvel]

13 minutes ago, moray james said:

but you don't want to hear 1k coming out of a Classic in a home rig

 

Why not? That's where Nico runs his, as a two way... although I may head for around 800Hz once my son and I actually build.

[moray james]

15 minutes ago, Marvel said:

 

Why not? That's where Nico runs his, as a two way...

for the same reason you do not see designers running say a fifteen inch woofer that high, the horn playing 1KHz will have all manner of cancellations and additions of frequencies across the mouth and these will screw up the image because you tweeter will be covering the same range and your ear/brain combination will hear both at the same time in different locations and not be able to tell which is the correct one to listen to. The dispersion of the bass horn and the tweeter horn at crossover become very different and this is very noticeable and becomes more so the higher up you go hence the goal of a 500 Hz crossover in big two way designs.

[Marvel]

Just now, moray james said:

for the same reason you do not see designers running say a fifteen inch woofer that high, the horn playing 1KHz will have all manner of cancellations and additions of frequencies across the mouth and these will screw up the image because you tweeter will be covering the same range and your ear/brain combination will hear both at the same time in different locations and not be able to tell which is the correct one to listen to.

 

Shhhhh!  Don't tell Nico.

 

 

[moray james]

Just now, Marvel said:

 

Shhhhh!  Don't tell Nico.

 

 

you can learn to listen around such issues but it does not make them go away and you might not notice this as a problem until you actually hear the problem resolved. Some folks simply focus on other aspects of the playback performance in this case powerful bass with low distortion and great dynamics. That's a lot to be happy about right there!

[ClaudeJ1]

On 10/14/2020 at 5:17 PM, noviygera said:

I have been using Peavey FH1. Is there a design in-between the FH1 (LaScala) and full blown MWM? 

The MWM is just too big for my space but I can definitely go larger than the FH1 to hopefully get 70-80hz horn

Yes, it's called a Quarter Pie, since I designed that and the Super MWM. The quarter pies uses roughtly the same corner space as an FH-1 and is flat to 50 Hz. instead of 90. It's only a 90-135 degree single fold but I never used it past about 300-400 Hz. Very easy build.