Seas Prestige 3 way all metal driver Project

[saevox]

I have a 3 way SEAS Prestige line speakers. They are H1208, H1141, and H1212. Built these as my first speakers back in 2008 and looking to rebuild them with better cabinets and get the tweeters at a more ideal height. I was considering expanding into a MTM arrangement with another H1141 mid range driver, and adding another H1208 to the low end for a WW MTM setup. I was wondering if this would be worth my while to even rebuild these or expand them to the WWMTM. I went into this project blind on the advice of a sales rep from MadiSound. I have attached the crossover and leap modeling used to make these speakers.
I am looking for feedback from experienced and more knowledgeable builders than myself on this design and if I should pursue it or just go in another direction. I do not want to sink more money into these if they are not that great of a design.
Also if I expand the number of drivers what modifications should I make to the crossover or should I start over with a whole new design.
I have the ability to build the cabinets and more than enough tools to get them done correctly.

Attached are the LEAP and Crossover

[BOBinGA]

Those are all fine drivers. I could live happily ever after with those in a good design. Your goal of rebuilding to get the tweeter to ear level is a good idea. But why do you want to double up the woofer and mid? There are some things to be gained by this, but it not nearly as important as having a good crossover. Doubling the drivers does lower distortion a bit and can possibly increase output (if you need it). The existing drivers should be plenty loud unless you have a very large room.

The LEAP crossover is probably close, but can more than likely be improved. They are developed without regard to box size and height, so they are not as optimized as you could get. If you want to rebuild, this might be a good time to get started on measurement. Do you have any experience with measuring drivers with a microphone and some software? If not, this would be the best place to start if you want to improve on the existing design.

-Bob

p.s. I cannot read the crossover you attached. Its way too small to see the values and get an idea of them. The same goes for the trace although it does look OK. Can you post better pictures so we can get a better idea of what you have now?

[saevox]

I had to shrink the pdf to get it with in the 100kb limit. I will try to get a better one in here. I do not have to add more drivers, just trying to build these with room to grow. I am also open to swithing out drivers if there are others in the line that would work better, like a different mid range etc. I will work on getting that better attachment up and if anyone has any suggestions on driver alignment etc I am open to it all. I should have the attachments up tommorow, if any one knows the best way to get quality attachments under 100kb i am all ears.

[BOBinGA]

saevox,
Take a look at Roman's Alpheus design. It will give you a good design for a new box since it uses your woofer. Its crossover will be similar, but you will likely have to make some changes to account for the different efficiency of your drivers.

http://rjbaudio.com/Alpheus/alpheus.html

-Bob

[saevox]

here are what I beleive are better copies of the Leap and xover.

[saevox]

I was doing some more reading on this and I think I could use the Zaph L18 build Zaph L18 Build . Add the L22 as a base box like RBJaudio does RBJ Build . I have my mains setup to bi amp as it is and I could use the rbj audio low pass filter for the L22 and have the top end handled by the zaph l18 build. I already have the L18 build doing my surround work as it is.
The L22 would be like a bass box add on to the L18 build to make it 3 way
Does this seem like a plan or am I missing something?
Also would I have to bi-amp or could I tie both sets of xovers (l18 zaph, L22 RBJ) into the same set of terminal plugs?
Then I could get 2 more L18 to handle the surround duty since I already have the tweeters.

If this all works out I will have to come up with some sort of center channel as currently I run 2 Seas L16 4 ohms and the the 27T tweeter in a vented enclosure mtm horizontal. Any suggestions on a center? I will have the 2 Seas L15 if I do the towers as described above...

[BOBinGA]

The Zaph/RBJ monster actually sounds like a good idea. The only thing you will need to work on is the cross from the L22 bass to the L18. The L18 to tweeter cross can remain the same as Zaph shows it. You can use the RBJ cross from the L22 to the L15 in the Alpheus design as a start since the L15 and L18 are the same impedance and only half a db differnent in sensitivity. If you don't add some type of crossover between the bass box and the Zaph L18, you will get an exaggerated upper bass that coild be rather unpleasant. but you can build the L22 low pass into the bass box and the L15/L18 high pass into the Zaph or make it outboard and you could then just use one speaker wire to the cabinet and run the Zaph and the bass box on it. You might have to add some additional resistance before the input of the Zaph to get some BSC.

-Bob

[bobhowell]

I have been looking at Troels Gravensen's designs for a while planning to build one someday.Site

I am now using a small 5" 2way placed on boxes with 10" Peerless xo at 120hz.

I am looking at several 4" and 5" designs to expand my options. RJB's project mentioned above now uses drivers that are available.

I use the xo in my sound card to cross over to the bass bins. It can be anywhere up to 250hz.

These small speakers can also be used elsewhere around the house paired with subs disguised like objects of furniture. The trick seems to be to use 3 or more subs to even out the bass around the room. This is a long term plan that guides my builds towards small 2ways.

Now I have also been considering this 2way
from Madisound to be used alone in my man cave. It seems to be a great buy as it covers the same range as a 3 way but with the money in drivers rather than xo parts.

Many projects, so little time...

Bob