POTENTIA MAXIMUS is an LFE channel in my Home Theater I call “The Experience.” It was a labor of love.
POTENTIA MAXIMUS is a dual cabinet, opposed driver configuration LFE system. Each cabinet is 18.10 cubic feet internal volume with a system tuning of 14.4 Hz. This project was an evolution of LFE design and implementation. It started as a small build utilizing existing drivers and amps and evolved into The grandest system that I personally or physically could assemble. Each cabinet consists of approximately 8.5 sheets of MDF and Oak Ply. I feel that the melding of these materials gives extremely good build qualities. The ply adds strength and durability, while the MDF allows for superior machining and it is extremely consistent and nondirectional in structure. Each cabinet including the grills weighs in at approximately 1000 pounds. The drivers and PR’s alone in each cabinet weigh roughly 225 pounds- a true heavyweight.
All of the panels are minimally 1.5″ thick and the 2 baffles are each 2.25″ thick. The granite was applied in the same fashion as each panel. The entire surface was epoxied and the entire granite slab was bolted to the cabinet and became part of the system. Thus, adding 1.25″ of thickness to the top plate and the base. It also added over 245 pounds to the system. With the drivers configured as they are, the cabinets take up the bare minimum of floor space, and results in a cabinet that neither vibrates or rocks due to the movement of the PR’s in the system.
Newton really had something with those laws of motion.
The system consists of:
1. 4- 18″ TC Sounds LMS 5400 Active Drivers capable of delivering 32 liters of displacement at 38 mm xmax.
2. 8- 18″ TC Sounds Variable Mass Passive Radiators (VMP’s) capable of delivering 76 liters of displacement at 45 mm xmax.
3. 2- Crown ITech 8000 power amplifiers. Each amp is capable of delivering 8000 watts into an 8 ohm ridged load on a 220 volt service.
4. 1- MIC2200
Special thanks is in order to the following people.
1. NEO Dan. Dan has been instrumental in the development and ultimate production of this system.
2. Michael Hurd. Mike’s knowledge of paint helped transform this behemoth into something special.
3. My parents. My parents gave me an unobstructed place to assemble this project which would have not been possible otherwise.
4. My Nephew Mike helped me in varying aspects of assembly and final assembly of both units. Mike helped greatly in mounting drivers and PR’s.
5. My brother Mike helped me in assembly and moving. He also supplied many of the clamps used in assembly.
6. My brother Barry helped in assembly of grills. He was also responsible for designing and manufacturing the badges for each cabinet.
7. My friend Keith helped in many aspects of assembly and also responsible for helping move cabinets to my home.
8. My friend Joe helped in many aspects of assembly and moving cabinets to my home. Joe also helped apply granite to the cabinets.
9. Big Rob. He is bigger than me! Helped to move cabinets to my home.
10.Bossobass supplied magnets to me for grill application. Thanks!
11.Kyle Keating Helped with various technical aspects of design and assembly.
12. Ilkka Risannen Tested the LMS 5400’s and shared his thoughts of the drivers with me and offered design assistance.
Thanks also goes to all at the AVS forum and the Home Theater Shack. Thanks for all the suggestions and assistance!!
I have been asked many times about how much did this system cost. I have gathered all of the numbers that I have and here is the list to the best of my knowledge.
Total cost of build.
1. 4 – 18″ LMS drivers $ 3600.00
2. 8 – 18″ VMP’s $ 2400.00
3. 2 – Crown ITech 8000’s $ 6000.00
4. 1 – MIC2200 $ 100.00
5. 4 – granite slabs + finishing $ 1100.00
6. 2 – custom designed logos $ 3600.00
7. 12- sheets Oak Ply $ 540.00
8. 5 – sheets MDF $ 100.00
9. Paint, primer & supplies $ 500.00
10. Bolts, cap screws & washers $ 185.00
11. Grill cloth and materials $ 85.00
12. Tung oil finish and stain $ 110.00
13. 36 Pillows @ $4.50 $ 175.00
14. Internal wiring and connectors $ 15.00
15. Epoxy for granite application $ 32.00
16. Electrical upgrade $ 575.00
17. Inwall Speaker wire runs& Neutriks $ 225.00
and wall plates
Total material cost $19337.00
The big question seems to be, “Is the total system worth what I paid, let alone the time invested in it.” To this statement, I say, “Absolutely!” Of course I could have gone with much cheaper drivers or sealed or ported and eliminated the PR’s, and, I did not need the Itech amplifiers at all. I could have used MDF for the top and the base instead of granite, I could have not had the badges made, I could have used canned spray paint, I could have used cheap spandex for the grills-as a matter of fact, I could have eliminated all the grills entirely. Instead of all of the I could haves, I can say “I did.” I actually did this project as planned from beginning to end with no compromises. I took my time and waited for the things to come together. I am very pleased with the results. I have absolutely no regrets and the outcome was exactly as planned. Could I have achieved the same level of performance using a different system that was more cost effective? I am sure I could have gotten a lot more drivers and a lot more amps for less money, but on an apples to apples comparison, I would be hard-pressed to beat this setup. I definitely think I made the right choice as far as drivers goes. These things are absolutely phenomenal.
For me, the project was totally worth the effort. It has gained me many new friends, allowed me to utilize skills that I was not sure I possessed, taught me many valuable lessons for later projects and allowed me to spend over 2 years working on a hobby that I completely enjoy. The actual building process was as much fun as the listening and tweaking process. Now, as far as “How does it sound?” All I can say to that is it has exceeded all of my expectations. The sound and overall feel is phenomenal. The total output is extreme to say the least. Overkill? I say to this, “No!” I just consider it as headroom. I like my system to sound powerful as it is cruising along. As a matter of fact, before this addition, I was running things at 5 channels with no LFE. I loved the sound, and now it is just that much better for me. As far as bass goes, I got what I was looking for. It is visceral- to say the least. Movies that we have seen many times before are now even better. With test tones, I feel that the house is actually undulating back and forth- just like when you see the videos of earthquakes. It feels like I am riding a boat in a real bad sea. My plans are to get the system as complete as possible before having some sort of GTG, so that people more knowledgable than me can give a totally non biased opinion of the LFE setup.
I thank all of you guys for the support and help in the last few years, and I hope to see and hear from any and all who wish to know anything I can offer about this build.
Please feel free to ask any questions or post comments.