[dyohn]

re: the top of the port being too thin.  Machine the top baffle out of MDF with a groove for the port, but add a sheet of aluminum across the top covering the groove to form the top plane of the port (and the top of the speaker.)  No worries about someone using it as a handle and breaking the leading edge, plus a nice anodized aluminum top surface might look great.

[Kevin Haskins]

Ok guys... I pulled the plug on the port on top.   This is the latest version.    Check the PDF as you can rotate the part.   Anyone who can find the port gets a penny.   

I've been scratching my head over finish options.   What do you guys think of a fine grain black leather wrap on the baffle & top?   It would add some texture and its something I've seen in a couple high-dollar speaker designs.   It can look good used in moderation and it keeps fingerprints off the baffle.   



http://www.diycable.com/main/pdf/monitor.pdf


Please give me some input.

[Wayner]

I've done my share of industrial designing. I've always found respect in form follows function technique. It's hard to dispute when a design looks natural and offers no questions of "why did you do that".

Sounds simple enough, but very hard to execute. I like speakers that do not offer a place for some drunk to put his drink, or the bride to think it's a good place to put a house plant. Good God, woman, it's a speaker. The curved housing is a great trend as it is proven to help eliminate standing waves.

Some criticism is the transition from one form to another. It is slightly un-natural and something that needs to be worked on. I would consider a way to have the tweeter exposed even with the grill attached as most people listen to the speaker with the grill off. Nice to have the grill on all of the time if it enhances the appearance.

Another design idea is to put the wire connections off to the side or on top, rather than on the rear as everyone else does. It's a pain in the ass to have to move the speakers to get at the speaker wires. If this is going to be a shelf mount type, put feet under it right away. Just like an amplifier has feet, the speaker does too. If they put it on a shelf, they got what they need. If they put it on a stand, then so be it.

Just my 2 cents worth.

Wayner

[Sonny]

Kevin, port is underneath the front bottom baffle...
Slick!

[Kevin Haskins]

Here is one without the grill.   I have yet to model the midwoofer.   It is going to be 7" driver, XBL^2 with about 20mm P-P excursion so it has plenty of output.   It uses a polyglass cone and a sizeable vented motor with advanced inductance control and highly optimized suspension design.    There is lots of Klippel time behind this one and price just wasn't a consideration in terms of build. 




Here is the PDF without the grill, tweeter in place.

http://www.diycable.com/main/pdf/monitor2.pdf


Here is one of the prototype midwoofers.



And the cone.   Note, we are not using a phase plug.  I'll have a inverted dustcap on this design.

[mfsoa]

Would it be possible to cover the front baffle with some kind of diffusion-buster?

[Kevin Haskins]

Here is the BL curve, which is a good 25% more than what the EX-6.5 supports.   The EX-6.5 already spanks the big boys in terms of usable output so this is WORLD FREAKING CLASS in terms of output and distortion.    The suspension was key to being able to design more motor.   The system is only as good as it's weakest link.    I don't have the suspension Klippel data on my laptop but it is every bit as impressive as the BL curve.   While I'd call this 12mm Xmax one-way, the device has plenty of suspension travel.   The limiting factor being the surround.   

Pulling out all the stops on this one.   

[Kevin Haskins]

I've done my share of industrial designing. I've always found respect in form follows function technique. It's hard to dispute when a design looks natural and offers no questions of "why did you do that".

Sounds simple enough, but very hard to execute. I like speakers that do not offer a place for some drunk to put his drink, or the bride to think it's a good place to put a house plant. Good God, woman, it's a speaker. The curved housing is a great trend as it is proven to help eliminate standing waves.

Some criticism is the transition from one form to another. It is slightly un-natural and something that needs to be worked on. I would consider a way to have the tweeter exposed even with the grill attached as most people listen to the speaker with the grill off. Nice to have the grill on all of the time if it enhances the appearance.

Another design idea is to put the wire connections off to the side or on top, rather than on the rear as everyone else does. It's a pain in the ass to have to move the speakers to get at the speaker wires. If this is going to be a shelf mount type, put feet under it right away. Just like an amplifier has feet, the speaker does too. If they put it on a shelf, they got what they need. If they put it on a stand, then so be it.

Just my 2 cents worth.

Wayner

I'd crap myself if someone sticks these on a shelf.  For that application though if they HAVE to go on a shelf I'd point people to just using some stick-on bumpers.   You can buy a gaggle of them from Digikey for a couple dollars.    Primary methods of use should be either stand mounted or wall mounted in HT systems.    I've found a wall-mount that supports the weight and I'll design a mounting device in the rear that works with an off-the-shelf wall-mounting device, not requiring any cabinet modification.   

I've tried to keep all the lines consistent.   I've played with it TOO long and some of it comes down to personal taste.    The things I'm wishy-washy on at this point is the top-rear and the contour on the top.   

[Kevin Haskins]

Kevin, port is underneath the front bottom baffle...
Slick!

You win the penny!   You can apply it to your next purchase at the DIY store.   

[Kevin Haskins]

Would it be possible to cover the front baffle with some kind of diffraction-buster?

The horn has the advantage of controlling directivity.   You don't get baffle diffraction like you would from a typical dome tweeter.   You get the typical baffle step response going from 2Pi - 4Pi radiation but not the same kind of baffle diffraction issues that show up in the on-axis response.     That is one of the advantages of the horn.   That and the fact that we can cross that beast over down around 1K means that the response is very clean both on/off axis regardless of the baffle.   

[dyohn]

Very nice work, Kevin.  The new woofer looks pretty spectacular, and I like the port relocation.  Hmm, a brain-fart just popped out: if the top baffle sported a PR on that nicely sloped plane then the port is not a problem...

[Kevin Haskins]

Very nice work, Kevin.  The new woofer looks pretty spectacular, and I like the port relocation.  Hmm, a brain-fart just popped out: if the top baffle sported a PR on that nicely sloped plane then the port is not a problem...

Ha!   I went through that approach about a month ago.   We kicked around an idea for a slot loaded PR.    I ultimately rejected it because it complicated cabinet design & placement on the monitor & center channel.   It works great on the tower because you have all kind of baffle space to burn.    Putting it on top is ok in terms of placement but depending on the mass, can cause long-term issues with suspension sag.   

I need to get some drivers sent to you, don't I?   

[dyohn]

Very nice work, Kevin.  The new woofer looks pretty spectacular, and I like the port relocation.  Hmm, a brain-fart just popped out: if the top baffle sported a PR on that nicely sloped plane then the port is not a problem...

Ha!   I went through that approach about a month ago.   We kicked around an idea for a slot loaded PR.    I ultimately rejected it because it complicated cabinet design & placement on the monitor & center channel.   It works great on the tower because you have all kind of baffle space to burn.    Putting it on top is ok in terms of placement but depending on the mass, can cause long-term issues with suspension sag.   

I need to get some drivers sent to you, don't I?   

Great minds and all that!  But as usual, I am about a month behind the curve. 

There is no rush my friend.

[mfsoa]

If the port is on the bottom of the front baffle, this would require the user to scoot the speaker foreward on stands to leave the port free, no?

Could you get a performance advantage by creating an integral stand that somehow couples to the speaker port with a port of it's own? I'm thinking that if there is a benefit to a bigger/longer/different shape etc. port and there is no room in the speaker, integrate it into the stand. Like a bass horn in the stand? Or some way to "trick" the speaker into thinking it's bigger than it is, by coupling the port to the port in the stand. Make a transmission line stand instead of TL speaker?  Sounds $$$.


Obviously I know nothing about speaker design!

-Mike

[Kevin Haskins]

If the port is on the bottom of the front baffle, this would require the user to scoot the speaker foreward on stands to leave the port free, no?

Could you get a performance advantage by creating an integral stand that somehow couples to the speaker port with a port of it's own? I'm thinking that if there is a benefit to a bigger/longer/different shape etc. port and there is no room in the speaker, integrate it into the stand. Like a bass horn in the stand? Or some way to "trick" the speaker into thinking it's bigger than it is, by coupling the port to the port in the stand. Make a transmission line stand instead of TL speaker?  Sounds $$$.


Obviously I know nothing about speaker design!

-Mike

Mike,

I've thought of doing a stand designed for the individual speaker but it limits the appeal of the device.   A lot of people already own stands or have a preference for one vs. another.   If you paint people into a corner on their choice of stands you may eliminate yourself as the supplier of their speaker.    I've found the same goes for active designs.   I can find a host of good reasons to do active speaker designs.   The problem is that those are not the things that MOST customers will appreciate and I have to make smart business choices as first priority.   

In terms of the port, I have a couple different speaker stands and speakers similar in size to these.   They all protrude a fair amount past the front lip of the stand so there are no clearance issues.    Even on a flat shelf, you would want to use rubber footies or something on the bottom of the cabinet.    The port is a good inch or so from the plane of the shelf so it shouldn't be a problem once the speaker is slightly raised off the shelf.     

Good points though and I appreciate your input.

[Voodoo Rufus]

You sure kept the wraps on that woofer...
This going to replace or augment the EX 6.5?

[Kevin Haskins]

You sure kept the wraps on that woofer...
This going to replace or augment the EX 6.5?

It is only in the finished speaker designs.  The EX-6.5 is going to remain in the lineup for kits and raw driver sales.