Started my new custom SDA's today

ben62670

Lasareath wrote: »

Hey Ben, Looking really good so far!, I'm trying black Lacquer on my side panels instead of grille material and it's turning out to be a royal ****.

I may just bring the original side panels to an upholstery shop and have them put new material on them.

Are you going to glue the cabinet together like Polk does?

Sal

I am using liquid nails on all joints, and then caulking them with it. Also tons of counter sunk screws!

hearingimpared

The Nutty Professor! I think you might look like the guy in the old Memorex commercial when you first fire them up!

ben62670

hearingimpared wrote: »

The Nutty Professor! I think you might look like the guy in the old Memorex commercial when you first fire them up!

I have also heard back to the future when MJF hit the guitar!

RuSsMaN

Tell me you are going to do some more bracing than that (as shown in the pics), for the finished product. You need a least a half dozen dado style down the length of that box.

Please don't load all those drivers without additional bracing, the box is surely going to flex with current setup.

I applaud the effort, I really do. Do you guys/gals not realize that engineers spent countless hours designing these things? Charts, graphs, anechoic chambers, slide rules, silly putty? To think one can 'throw together' a pair of SDA is unfathomable for me. How did you determine the box size, mass, and tuning of the passive radiators?

Honestly, I hope you are successful, I really do. On the surface, all I see is a Frankenpolk, and lot of wasted effort (and sought after SDA parts). Get a grip on SDA, and reality for that matter. Keep us posted as to the progress.

Cheers,
Russ

ben62670

RuSsMaN wrote: »

Tell me you are going to do some more bracing than that (as shown in the pics), for the finished product. You need a least a half dozen dado style down the length of that box.

Please don't load all those drivers without additional bracing, the box is surely going to flex with current setup.

Cheers,
Russ

Its braced even though there is no span greater than 14.5 inches:)
I am also going to treat the interior with asphalt based sound deadening material before the poly mats.

Edit
I made that mistake on my first experimental. If I put my head against the box my eyes went screwy.

WolfKiyoshi

Back To The Future reference works perfectly Ben by the way i suggest moving out to the country.. because those speakers may possibly piss off people within a 10 mile radius

hearingimpared

WolfKiyoshi wrote: »

Back To The Future reference works perfectly Ben by the way i suggest moving out to the country.. because those speakers may possibly piss off people within a 10 mile radius

And level land cause those babes will cause earthquakes.

ben62670

I'm in Fort Lauderdale. The only thing they will worry about is them starting hurricane. Hey I think I'll play Scorpion's "rock you like a hurricane next scare"

WolfKiyoshi

play Iron Man by Black Sabbath through them kind of a "waking the beast" type sound to me plus it'll just sound awesome lol

heiney9

So, do you have to stack a few phone books under a tall bar stool to be in the sweet spot? Maybe you are 7 1/2 feet tall? :eek: .

Good luck Ben

H9

ben62670

heiney9 wrote: »

So, do you have to stack a few phone books under a tall bar stool to be in the sweet spot? Maybe you are 7 1/2 feet tall? :eek: .

Good luck Ben

H9

Actually the middle of the array is right at where I wanted it for seating position. The center of the driver array is about six inches higher than my ears on the sofa. When you are at a concert the stage is almost always a little higher when you have good seats, and also movies. I did A LOT OF PLANING before starting this project... A LOT.
As far as progress for today, everything is working great so far.

"I just love it when a plan comes together" (A Team)

ben62670

RuSsMaN wrote: »

Tell me you are going to do some more bracing than that (as shown in the pics), for the finished product. You need a least a half dozen dado style down the length of that box.

Please don't load all those drivers without additional bracing, the box is surely going to flex with current setup.

Cheers,
Russ

I just wanted to add a little onto Russman's post. MDF is very flexible. I do strongly advise real bracing in a project like this. A good example is on one of my boxes one of the long pieces had a 3/16" gap. While using a screw gun I pulled that MDF without a problem. This stuff is very flexible!

Systems

Wow Ben that is a very ambitious project.May I ask why you didn't just use active crossovers instead of the inline passives?

engtaz

Active too easy LOL

ben62670

GV#27 wrote: »

Wow Ben that is a very ambitious project.May I ask why you didn't just use active crossovers instead of the inline passives?

I just bought an outlaw 990 pre. I have spent probably 60+ hours on studying active crossovers. The op-amps in the 990 are very dynamic, and clean. Almost all actives in my range are designed for Pro Audio with some pretty unappealing specs. I have also looked at using higher end auto crossovers. I have actually used them with my setup, and was quit happy with them. Nothing is set in stone right now except that I am not going to use the standard in the speaker crossover. The passive in lines do not require any power, and are very clean. I have used some in past experiments, and was very impressed.

Edit
I just finished building the second tower. Most of the holes are cut, and recessed for flush mounting.

Systems

If decide you want try the active route and you are into doing a little DIY electronics Marchand sells some excellent active crossover kits or just the PC boards that you can use your favourite opamp and resistors etc in. http://www.marchandelec.com/xm9.html

Also the Behringer CX2310 is pro unit that while being inexpensive Ive heard of guys using it with excellent results in hi end systems.http://www.behringer.com/CX2310/index.cfm?lang=eng

ben62670

GV#27 wrote: »

If decide you want try the active route and you are into doing a little DIY electronics Marchand sells some excellent active crossover kits or just the PC boards that you can use your favourite opamp and resistors etc in. http://www.marchandelec.com/xm9.html

Also the Behringer CX2310 is pro unit that while being inexpensive Ive heard of guys using it with excellent results in hi end systems.http://www.behringer.com/CX2310/index.cfm?lang=eng

Thanks GV I have looked into both of those options. I am not ruling either of the two out. I have just decided to go passive at least for now. A lot has changed(especially with this project), and have had very pleasing results before with the passives. I will try active via 12v battery (no noise) also. it is a simple test. These will not be finalized for a long time! If ever!:D

Thanks Ben

Systems

ben62670 wrote: »

I have just decided to go passive at least for now. A lot has changed(especially with this project), and have had very pleasing results before with the passives.
Thanks Ben

Cool Ben,I will be watching with interest as your design progresses.:)

ben62670

Just some more pics. A fellow Polkie recommended that I put some tweeters in them so...:p Here they are.:)

engtaz

Fantastic work. Sure makes my back hurt.

Great job Ben

ben62670

engtaz wrote: »

Fantastic work. Sure makes my back hurt.

Great job Ben

Thanks ET

dudeinaroom

um....ah.....my back hurts. Looking good.

ben62670

Oh yeah the center of the tweets are 53"s from the bottom, just right for my setup.

Mike Reeter

ben62670 wrote: »

Just some more pics. A fellow Polkie recommended that I put some tweeters in them so...:p Here they are.:)

Damn man,That's the first set of speakers I've seen that takes a forklift to move them around:D

ben62670

I'm 6 foot, and over 200lbs. These things make me feel teeny tiny, and thin:)


Edit 10' ceiling

schwarcw

WOW!:eek:

Nice work Ben!

MillerLiteScott

Big Stuff!!!!!!

Systems

Nice work,I bet you had a truck full of MDF dust after building these.

ben62670

GV#27 wrote: »

Nice work,I bet you had a truck full of MDF dust after building these.

I started in the shop. I cleaned one edge with a flush cut bit on a router. It made a big mess. Loaded it on the fork truck, and went outside. It makes an incredible amount of dust. Mostly using the router with the plunge bit to do 20 holes per cab. I used a hole saw for the tweets. Do not attempt a project like this indoors!:eek:

Sumbrada77

Hey Ben great DIY you have going! No doubt they will be loud!!! Question for ya, I am redoing Monitor 10s crossovers (original series) and will be posting my work. What do you use to do the thumbnails to blow up pics?
Thanks!