Maximus "Build Thread"

[Thumper Tom]

My goal for this build is some nice high end towers for my man cave. I am basing part of my design off of Elemental Designs EL8 series speakers. The goal is to have a full 7 speaker setup using all the same drivers.

The drivers that I have chosen to complete this task is the:
Peerless 830869 8" Nomex Cone HDS Woofer
Tang Band 75-1558SE 3" Textile Dome Midrange
Morel CAT 408 1-1/8" Compact Soft Dome Tweeter

For the towers I will have two 8" Peerless, 3" TB Mid, and Morel tweeter.
The drawing is a little different, but I plan on relocating the port to the rear of the box and the mid will be mounted on the backside of the baffle with a 45* chamfer.



So far with this project I have received the drivers and done some frequency response testing and working with PCD to get the hang of things. Here is what I have come up with so far using SPL trace and ZMA files I got with DATS.





The response is nice and flat and I also have the baffle step included in the woofer response file. After playing around with different settings in PCD and using a couple other software, I really tried to keep the crossover simple. If anyone spots a bad thing let me know, I will not be able to test the true FR of the drivers until I build the boxes.

Give a little idea of the box, it will be about 75L with a 4" port tuned to 37 Hz.



If anyone has suggestions/comments they are more then welcome.

[morris]

Re: Maximus "Build Thread"

This has the potential to be a really good speaker when done right. Is this a purely simmed design? It does not look like you have put in the driver diameters and offsets. Did you also ran this into Response Modeler to account for baffle step/diffraction and was the minimum phase extracted for the drivers?

[Wolf]

Re: Maximus "Build Thread"

Ditto, Morris.
Wolf

[Thumper Tom]

Re: Maximus "Build Thread"

Here is an update image with all the diameters, listening distance, height, driver location, and minimum phase.



None of the component values were changed and it still comes out pretty solid. The FR is simulated with using SPL trace, response modeler, and the ZMA file is the real driver. The FR file also has minimum phase, box response, and baffle step included.

Does my crossover look good or do I need to do some improvements?

[peepaj]

Re: Maximus "Build Thread"

Tom, your driver locations should be -.127 and -.0635 the way you have it the woofers and mid is above the tweeter. Also you don't have a z offset this will have an effect on your crossover.

[isaeagle4031]

Re: Maximus "Build Thread"

what's up with the series resistor on the woofers?

[greywarden]

Re: Maximus "Build Thread"

Already looks to me like you need a bigger coil on the woofer that bump there will likely turn into an audible wart. Also when you have the z offsets in, you should pan up to 45 degrees off axis and see if you need to lower or possibly raise your crossover points.

[Thumper Tom]

Re: Maximus "Build Thread"

Tom, your driver locations should be -.127 and -.0635 the way you have it the woofers and mid is above the tweeter. Also you don't have a z offset this will have an effect on your crossover.

When figuring the driver location, is it based off of a corner(top left, right, bottom) or is it based off of the tweeter?

How would I figure the Z offset?

what's up with the series resistor on the woofers?

I used the resistor to raise the impedance so it would not drop as low but I could just remove it.

[PWR RYD]

Re: Maximus "Build Thread"

Driver offsets are referenced off the tweeter.

[greywarden]

Re: Maximus "Build Thread"

A resistor in series with the woofer is asking for a fire. I'll refer you to the "hot crossover" thread lol

[Wolf]

Re: Maximus "Build Thread"

read...

http://techtalk.parts-express.com/entry.php?74-Some-optimization-criteria-and-some-tips

http://techtalk.parts-express.com/en...me-2-The-setup!!

http://techtalk.parts-express.com/entry.php?123-quot-Tips!-Volume-3-quot

We also cannot see your individual driver phases, power response, or your electrical phase. These are important factors.
Later,
Wolf

[Limelight]

Re: Maximus "Build Thread"

Thanks for postings these Wolf! I've been wondering how to properly model a tank in PCD. Sweet!

read...

http://techtalk.parts-express.com/entry.php?74-Some-optimization-criteria-and-some-tips

http://techtalk.parts-express.com/en...me-2-The-setup!!

http://techtalk.parts-express.com/entry.php?123-quot-Tips!-Volume-3-quot

We also cannot see your individual driver phases, power response, or your electrical phase. These are important factors.
Later,
Wolf

[Thumper Tom]

Re: Maximus "Build Thread"

I have a lot of work ahead of me. I adjusted the driver locations(x, y, z) and wow, went from good to complete cr@p on response and phase.

Thanks for the links Wolf, read through them, and now have a lot to digest.

I hope to build the enclosures sometime soon so I can get all my measurements from OmniMic, but for now the plan is to keep working with PCD.

[Wolf]

Re: Maximus "Build Thread"

I have a lot of work ahead of me. I adjusted the driver locations(x, y, z) and wow, went from good to complete cr@p on response and phase.
Thanks for the links Wolf, read through them, and now have a lot to digest.
I hope to build the enclosures sometime soon so I can get all my measurements from OmniMic, but for now the plan is to keep working with PCD.

Something told me if you had all the criteria entered that it would no longer be as pretty. That is one indication on someone doing a 'very-first-sim' for flat response- if it looks too pretty, it very well may be inaccurate.

Thanks for postings these Wolf! I've been wondering how to properly model a tank in PCD. Sweet!

They are linked in the Speaker bible in the sticky thread, so maybe you just did not see them. Glad it was of help.
Just remember you can fenagle PCD to do what you want by using 99999 for infinite connection, 99999 for every large cap if you can't remove it from the picture and just want a shorted cap position, etc. You can make it do things more than just a plain schematic. With careful usage, PCD is more versatile than you may think!

Later,
Wolf

[Thumper Tom]

Re: Maximus "Build Thread"

Wolf, would my listening height be set to 0 if my focal point is ear level, then adjust the angle to see what off axis response would be?

Something told me if you had all the criteria entered that it would no longer be as pretty. That is one indication on someone doing a 'very-first-sim' for flat response- if it looks too pretty, it very well may be inaccurate.



They are linked in the Speaker bible in the sticky thread, so maybe you just did not see them. Glad it was of help.
Just remember you can fenagle PCD to do what you want by using 99999 for infinite connection, 99999 for every large cap if you can't remove it from the picture and just want a shorted cap position, etc. You can make it do things more than just a plain schematic. With careful usage, PCD is more versatile than you may think!

Later,
Wolf