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zundelfan's picture

This is a great room. I loved seeing your set up. Thanks for posting the photos.

DrMark's picture

You are welcome. In fact you are the first to comment on this post, it has been up for some time. I think others have not understood what it is. You seem to understood what this room is all about. When my family come they just love to watch movies here, and so does my wife. I'm really happy when this system takes me to the opera house. Believe me when the source is right, it does not sound as if you are in this room. With the lights dimmed you really feel you are in the original venue.

Windzilla's picture


I am in love with your setup, very very nice.

who built all this custom cabnite work?

DrMark's picture

Obviously in a system this ambitious it took a number of craftsmen. I have been doing the R & D over the last three to four years. I started the detailed calculations for these speakers last October. Afer the calculations came pages of technical drawings. I'm still too slow with CAD, so I had to do the drawings with achitects rule, set square, protractor, pencil and compass. I envy my daughter's felicity with CAD.
This set up is part of the remodel of our lake home, my daughter Judy Grundstrom, was the architect. She has her own firm in professional partership with another architect. The firm is IOTA. The space where this room resides, used to be part of a large game room over the attached garage. This is now this room, plus the mechanical chase, and a very nice guest bedroom over looking the lake. My daughter drew the size of the spaces and left the rest of this room to me. She also left the design of the entertainment center on the first of the four level to me. Her specificatons were that all wood have a natural finish and no stains be used. The wood is red oak. I wanted to avoid the retro art deco look of so much current home theater architecture. I merely suggested a stage, with a contempoary clean look.
I did all the technical drawings between November 2005 and February 2006. The remodel started in earnest January 3. I did the rough in with the main contractor, Stuart Wick, of Benedict, and master carpenter Rich Lemke of Laporte, in January. When the rough in was complete, I had all the steel conduit placed by the electrician, Mark Mann, who lives a few miles away on Kabekona lake. He also placed an electic sub panel for the studio. This system requires six mains circuits. The amps supplying the front/left right speakers, also require a slow blow Square D breaker, because of the turn on surge.
I have a friend in Grand Forks ND, who has a cabinet shop, Brad Alberts, of Alberts cabinets. He agreed to have me in his shop to do the construction of the speakers, cabinetry and trim. Construction started in mid February. We started with the construction of the center speaker. Brad and I built that together. He needed to make sure I was safe in his shop, and was reasonably competent. For the rest of the construction, I and Brad's shop foreman, Bob, worked tirelessly until the middle of April. All the shop employees became fascinated and highly engaged in this project.
The only lines I was at all concerned about were the large bass lines. I tested one in the shop. I installed a set of the 10 inch SEAS Excel drivers in the bass lines of one of the front left/right speakers, and powered it with an amp and oscillator. The whole shop, both large rooms, filled with a deep bass note at low power, and everything in the shop not nailed down rattled. There was a very large movement of air from the upper two ports. The main augmentation was centered between 25 and 27 Hz. The output of a pipe connects to the air in the room much better than other devices, because of the phenomenon of encircling. As with the pipe organ, the bass tones filled the whole space evenly. Response was smooth and even through out the bottom two octaves. It was a succesful test, that boosted the morale of the entire staff, and we proceeded to finish the project.
Rich Binderup of Benedict installed the air extracion system for the power amps, and added air conditioning to the mechanical chase. I pulled the cables through the conduit at the begining of April. The TV cables, HDMI and component video, were expertly custom made by Blue Jeans cables.
The speakers, turntable case and computer station were made in Brad's shop. The shelving that holds the LPs and tapes at the back by the center back speakers were made by Rich Lemke.
In mid April Brad's shop closed for a day and he and his entire staff transported the finished mill work 142 miles from Grand Forks to Benedict, as soon as Poncho Masser of Akeley had laid the carpet.
I made aluminium rails for the racks in my shop, and also the case that contains the switching and crossover control balance circuits. The amp switching is 24 volt DC via relays. This way there are no AC circuits with high current to induce hum in the audio circuits. I have a 1200 square foot detached work shop at Benedict. That is well equiped with a large central compressed air supply, band saw, drill press, welders, plasma cutter etc. I ran an air hose from the shop to this room. The last two weeks of April were unusally warm sunny and pleasant. I could use the deck outside the studio for cutting. I installed the equipment, cut and installed the fill panels the last two weeks of April and wired the studio. I did the miters round the non rack mounted equipment. Brad made two further trips to Benedict to asssist with trim out. Believe it or not all the equipment came up first time. I trimmed all the settings, balanced the channels, set the delays, and the power levels to the fill drivers.
All the equipment except the power amplifiers, is powered via generator compatible UPS devices. Any power irregularities cause the UPS devices to go to battery power via their inverters. I installed a large auto start generator at Walberswick House seven years ago, and the UPS devices deal with any irregularities from the generator also.
The whole set up has been an absolute joy and well worth the trouble. I do have an audiophile who is interested in purchasing a set of the three front speakers. The three fill drivers are driven via highly modified Shure SR 106 electronic crossovers. The mod for the center speaker is different than that for the right and left. I had two of these crossovers since new and was lucky to find a third on eBay. If others want this speaker system, Phil Marchand, of Marchand electronics, has agreed to fabricate a unit containing the three fill driver crossovers to my design, at a very reasonable price.
In this remodel there are a large number of SCR controlled light dimmers. These induced more buzz in the system than I liked. SCR devices are notorious for RF interference. Lutron engineers were very cooperative with me to get a version of their Maestro dimmers that would be satisfacory. Now no buzz in audible from the listening position. A faint buzz is only audible if you put your ear right adjacent to a loudspeaker driver. This is excellent curbing of SCR RF interfence. I was most impressed with Lutron's cooperation with me.
Every single individual involved in this project has given a level of interest, commitment and craftsmanship that has been truly refreshing and extraordinary, and for which I will be forever grateful.
This rather extreme system shows what is possible with current technology, and for that matter also the old. Visitors have been unversally fascinated by the vintage equipment in this system. Afer all this system spans the time from 78s to the latest seven channel digital wizardry, with equipment manufactured over a half century.
If you need more information please let me know.

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