Super MWM

[Edgar]

Browse around here for a while. See if what you want has already been done.

[jwc]

Hilarious.  You could never decide looking at all those.  Great site.

[ClaudeJ1]

3 hours ago, jwc said:

OK.  30-400.  That is doable.  I would wager ....just a guess..... that the output will drop noticeably under 35 Hz.

 

Everybody wants a sub these days.  Do a big straight axis to 50Hz then let that horn sub do the rest.

6 db down is what is used for Linkwitz-Riley Active Xovers and still very audible. 10 db down at 27 Hz. is still useful (only half as loud as full output). My Quarter Pies, which had a 51 Hz. cutoff still had audible bass at 37 Hz. so I suspect the extra 2.6 feet of this horn will easily take care of 99% of bass in most music. Even the funkiest of funk!!

[WillyBob]

I was going to ask a dumb Q ... but, I figure it will be answered w/o me asking.  More on horn principle ... the relationship between length, diameter/volume and pitch.

[Marvel]

17 hours ago, Edgar said:

Browse around here for a while. See if what you want has already been done.

 

The Jubilees are in there ... not official drawings.

[Dave1290]

19 hours ago, WillyBob said:

 

 me too. I was going to do MWM's and then you guys come up with this.  

I've been thinking about this since I first saw the post...  Where am I going to put them AND you guys are TOTALLY insane BUT in a kinda good way!!!  My kind of crazy!  😂 😂 😂 😎

[jwc]

Building Big horns is fun.   They sound awesome and to some....look awesome.  

 

I've built my share of them and one principle that sticks in my mind is...... is it worth the increase in physical space to gain say 15-20Hz.    Also more folds can introduce more FR anomalies.  Also the lack of horn expansion vertical can introduce another issues.   

 

To get a bass horn (not sub) to perform  in the 30's without being 1/4 space or 1/8 space......is always big.  Cool as heck to build.   The design posted here is just shy of 60 inches deep with a 67 inch width mouth.  Don't know the height.  If you are gonna use a sub anyway..........my suggestion would be a big straight axis.  Imagine a horn that big but you get to look down the barrel of a 15 staring at you and you can eliminate folds and most of the lack of area expansion in one direction (I would do dual 15's).

 

Either way.....build something that big....we will certainly watch the progress.  You'll have our attention.  If you can get a strong response less that 35Hz and play out to 400Hz with good polars and without big dips.......you have achieved something not commonly done.

 

jc

 

 

[WillyBob]

1 hour ago, jwc said:

Also the lack of horn expansion vertical can introduce another issues.

 

that was something that crossed my mind. Not familiar with horn speakers, but my dad spent a lot of time repairing brass/woodwind instruments.  I was going to ask about the bins being "flat" and increasing the "bell" end size

[Dave1290]

I trust in Paul Klipsch number uno, second thing is I don't know where the heck I'd put them w/LS & Heresey's.  Sure more rooms in the house I could use but the majority of my time is spent right here in my L-shaped living/dining room.  Then what do I do?  I really can't remember who borrowed my chain saw last so I guess room mods are out of the question BUT I'm still watching...  lol

[ClaudeJ1]

Here's a rough sketch of my proposed version 3 to match the last curve I posted. Hope Dave A. is willing to modify his plan. Having an abrupt step, like the first drawing of the op doesn't buy anything, sound wise. This mod keeps the outside intact and adds considerable length to the horn. I would opt for a 3-way system with no sub and a 300 Hz. crossover to a big midrange horn and a 4,000 Hz. Crossover to a 1 inch driver and big tweeter horn (B&C DE-250 or BMS 4550).

 

[jwc]

I would build that one before considering the original posted.

[ClaudeJ1]

3 hours ago, jwc said:

I would build that one before considering the original posted.

Well, you were not privy do Dave's evolution back to me. He did the plans, and I did the sim, so it was a bit of back and forth once he figured out how to splice two pieces of lumber together as to NOT shrink the mouth down to 60 inches wide. So I agree with your assessment of my V3 mod. here, skipping a few in-betweens. When you can get flat to almost 30 Hz. only HT requires a sub, and I definitely am a fan of a 300 Hz. horn and 3 way for the mids, just like you.

 

I also pulled a Dubyah by "misunderestimating" the last calculations. Here's the new one.

The Maximum woofer excursion is only 1.4 mm, which is what PWK measured in the Khorn while it was at full output. So the K33 only moves 1/16th of an inch while putting out 30 Hz. at 115 db while doing 105 db at 25 Hz. using only 2 Watts while the horn is in a corner. Subwoofers you say? NAH. However, a good high pass filter is highly recommended for those who would use a 100 Wat amp with this very sensitive horn.

Now to find a 300 Hz. midrange horn (I actually own 10 drivers and 2 horns that will do 300 Hz, so may the best one win!!).

[HDBRbuilder]

Still planning to try to do this with a skill-saw?  Looks much more like a table saw job to me!  Will the splice(s) of all the panels NEEDING a splice be a rabbet splice??  I would also opt for rabbet joints all around simply because it will stiffen the bass bin at the joints.  It will be way too much hassle for those tapered edges for the "ramps" to either side of the compression-slot motorboard unless a good table saw is utilized for doing that.  BTW, what will be your dimensions for the motorboard compression slot, anyway?  And I was wondering why you have such a large internal area for behind the woofer cone...or are my eyes deceiving me on that space?

[ClaudeJ1]

8 minutes ago, HDBRbuilder said:

Still planning to try to do this with a skill-saw?  Looks much more like a table saw job to me!  Will the splice(s) of all the panels NEEDING a splice be a rabbet splice??  I would also opt for rabbet joints all around simply because it will stiffen the bass bin at the joints.  It will be way too much hassle for those tapered edges for the "ramps" to either side of the compression-slot motorboard unless a good table saw is utilized for doing that.  BTW, what will be your dimensions for the motorboard compression slot, anyway?  And I was wondering why you have such a large internal area for behind the woofer cone...or are my eyes deceiving me on that space?

It should actually be larger, but it's better to lengthen the horn and have a slightly smaller back chamber in order to get to that 31 Hz. "big string B" on a 5 string bass. This is why you see a little bit of a curve sag at 45 Hz. and a slight peak before drop off.

[Dave A]

Hey guys I have been on the road for two days so just home and TIRED. Of course I will redo the plans. I have to admit I was thinking about this very thing on the way home today Claude. I feel kind of funny asking people to do verification of numerous changes and I had another though beyond this one too. If you don't mind doing the Horn Resp stuff I darned sure don't mind redoing CAD files.

4 hours ago, HDBRbuilder said:

Still planning to try to do this with a skill-saw?  Looks much more like a table saw job to me!  Will the splice(s) of all the panels NEEDING a splice be a rabbet splice??  I would also opt for rabbet joints all around simply because it will stiffen the bass bin at the joints.  It will be way too much hassle for those tapered edges for the "ramps" to either side of the compression-slot motorboard unless a good table saw is utilized for doing that.  BTW, what will be your dimensions for the motorboard compression slot, anyway?  And I was wondering why you have such a large internal area for behind the woofer cone...or are my eyes deceiving me on that space?

 

Go to the link above for the finger joint router bit and joining the plywood will be explained. Easy peasy. Regarding the Skill saw yes the table saw would be the way to go. But this is simple enough you could do it with the Skill Saw, I would cut the important bevel edge first and the rest after that using a clamped on guide. Easier to mate dimensions to the finished beveled edge. This assumes you have a good angle guide to set the blade with and not rely on the one on the saw.

  Believe it or not this is how I cut aluminum plate up to say 5/8 thick bevels or whatever is needed for welding or fit up. Wear long sleeves and good glasses and figure on hot chips finding your skin no matter what you do.

[Dave A]

On 6/18/2018 at 9:27 AM, CECAA850 said:

The mouth braces look off to me.  If you keep the front of the brace where it is, the rear of the brace should be in a straight line that ends up in the center of the space of the horn mouth at the rear of the cabinet, if that makes sense.  That would swing the rear of the braces outward slightly from where they are now. ( EDIT, it looks like the fronts should go inboard as the rears look centered. ) I wouldn't think it should be parallel to the outside wall.

 

Yes and the final plans will show that. I can move things around with the 3D CAD file and make drawing from those but taking the layout line drawing and changing that is a bit more complicated and I was lazy that night and in between two side ideas at the horn mouth. Figured it conveyed the basic idea though. My other thought is to just use 25MM Baltic Birch for the top and bottom and do away with those entirely. This is stock material in Nashville for like $56 a 5' x 5' sheet.

[Marvel]

On 6/18/2018 at 10:11 PM, WillyBob said:

I was going to ask a dumb Q ... but, I figure it will be answered w/o me asking.  More on horn principle ... the relationship between length, diameter/volume and pitch.

 

From my DJK archives:

Most W bins will make it to 300hz without too much difficulty. It takes really good design to get to 500hz. Bass response may be predicted by taper rate and mouth area. Area doubling every 8 inches is a 100hz taper rate. In 16 inches is 50hz, Etc. Most horns cheat the mouth area so stacking them makes them work much better.

[Dave A]

11 hours ago, jwc said:

Building Big horns is fun.   They sound awesome and to some....look awesome.  

 

I've built my share of them and one principle that sticks in my mind is...... is it worth the increase in physical space to gain say 15-20Hz.    Also more folds can introduce more FR anomalies.  Also the lack of horn expansion vertical can introduce another issues.   

 

To get a bass horn (not sub) to perform  in the 30's without being 1/4 space or 1/8 space......is always big.  Cool as heck to build.   The design posted here is just shy of 60 inches deep with a 67 inch width mouth.  Don't know the height.  If you are gonna use a sub anyway..........my suggestion would be a big straight axis.  Imagine a horn that big but you get to look down the barrel of a 15 staring at you and you can eliminate folds and most of the lack of area expansion in one direction (I would do dual 15's).

 

Either way.....build something that big....we will certainly watch the progress.  You'll have our attention.  If you can get a strong response less that 35Hz and play out to 400Hz with good polars and without big dips.......you have achieved something not commonly done.

 

jc

 

 

Height is 15.375 ID.

[Dave A]

Another thought I had on the way home was what would happen with an 18" woofer and greater height on the ID. See how this could become a never ending nightmare .

[ClaudeJ1]

2 minutes ago, Dave A said:

Another thought I had on the way home was what would happen with an 18" woofer and greater height on the ID. See how this could become a never ending nightmare .

With an 18" woofer, the mass rolloff might not make it to 300-400 Hz. IDK. Besides, I don't know if we could find the equivalent of a K33 in that size. But, I can try and model it. All it would create is wider rip cuts in the build.