View Full Version : Old FRC Controllers (Pre-NI)
04-30-2010, 12:54 AM
I am a former member and captain of 1391 now majoring in Music Business and Computer Science at SUNY Potsdam. I am also a staff engineer in the recording studio on campus. One of the many projects I am undertaking in my role is to design and build a series of wooden slats to cover the walls similar to those found in the studios at Capital Records in California. (See the wall in the background here (http://www.christune.com/Capitol%20Records%20and%20Studio%20A%20with%20Nick %20December%202003%20019.jpg))
I want the slats to be able to be controlled remotely from the control room of the studio by the engineer running the a session. I am already familiar with the old FRC system that pre-dated the new NI systems and know a number of teams have a few extra lying around not being used for anything. I am wondering if any of yalls teams have extra controllers lying around that could be put to use by another educational institution, though not for FRC use.
Was a great season and defiantly made me miss being a part.
04-30-2010, 10:29 AM
Check CD-Swap--someone had a 2007 system and a 2008 system. Not sure if those are still available. http://www.chiefdelphi.com/forums/parts.php?action=itemdetail&itemid=10654
04-30-2010, 12:49 PM
You could also try to skip the FRC controller and go for its guts - a Microchip PIC microcontroller.
There are many, many tutorials online how to program them, and if you have a student or business email (not a free one from yahoo, gmail, hotmail, etc.), you can get free samples directly from Microchip (save you about $4 plus shipping). I ordered some about a week ago and they just came in. (Just make sure you get a higher end chip, in the correct package - pdip)
Third party programmers are also pretty inexpensive (if you don't want to make your own), I just bought a USB with a zif socket for $30 from a seller on ebay.
Although, I can understand wanting to have something you're familiar with.
04-30-2010, 02:55 PM
Before we go too much further, you have to seriously look at what is exactly taking place in the studio you show. Capitol Records (as well as some other studios) use(d) this method in the belief that variable acoustics made better sounding records. With the slats closed a livelier sound was made while with the slats open a fair amount of absorption was introduced making the studio dead. Some instrumentation has been added since these designs were first introduced and a better understanding of mic technique, noise control, reverb (rt60), room cutoff frequencies and standing waves now rules designs. The design you show became popular after design and construction techniques introduced by F. Alton Everest became common. His ideas and use of materials controlled some of the variables listed above but design choice now is to fix the problems at the source rather than correcting with the use of other materials and construction. It was quite common to cover up standing waves of a particular frequency by having narrow band tuned acoustic filter built into the room. You can achieve the same effect in an anechoic chamber but a chamber is a poor choice for a music performance studio. Items like choosing the correct room ratios to minimize standing waves, making the surfaces in the room anything but parallel and controlling reflections to keep them out of the mics is successful and produces a room that performers like. Take a look at back issues of MIX Magazine and see the studios they highlight. There are even some interesting articles on studio design in the past as well. Articles written by Russ Berger are particularly interesting. Remember that correcting a problem after the room is built is infinitely more expensive than correcting the problem in design.
04-30-2010, 05:04 PM
Unfortunately when the room we are using now was built is was a storage room and not a studio so it has parallel cement walls. As of now, we are relying on clever mic techniques to prevent interesting sounding recordings. (we pretty much live by TapeOp) We have the room prety much covered in sound absorbing panels to deaden it out, most of which are a few years old and were a quick-fix when the room was first converted into a studio. As of now, we want to use these slatted panels to create a multi purpose studio that can be used for vocals, drums, guitar cabs, ect without having to move around huge pieces of equipment and without spending huge amounts of money. One of the guys in the studio here was chatting with an engineer from Capital and decided that this would be an interesting solution to the problem. Anyway, I am planning on planing the slats to be pentagonal to even when the slats are parallel they do not create parallel walls.
I will have a look around the Mixx site to see what I can find. I am also using a book another guy used for his Recording class which has a big chunk about room acoustics.
I like that idea. Any recommendations for controllers? I have an account at Mouser so any links?
04-30-2010, 11:15 PM
Two sheets of 3/4" heavy density or even MDF can be made to simulate a pretty good wall. The sheets can be added to the concrete walls in a tilted fashion to make the wall non-parallel ( you can do that in both horizontal and vertical if you have the room). Be sure to use 16" centers or less, and screw and glue everything together and the wall for most frequencies will be fine. Put the second layer on 90 degrees out from the first and insure that no joints in the first layer line up with joints in the second. The screw and glue technique will make the wall nearly impossible to remove but it won't vibrate or or interact with itself and it won't provide sympathetic vibration. The surface is smooth and can be covered in any fashion you want. Carpet will smooth out the high frequencies above 2kHz or you can stagger some live and dead material to smooth out the response but still make it live enough to feel comfortable when performing. Most acoustic musicians prefer some wood in the room to warm up the sound. Many studios use a wood floor but wood wall treatments also can help. Check out the RPG line of diffusor products here http://www.rpginc.com/. I have used the Studio in a Box products with surprising results. The QRD diffusors and Omniffusor are also great products but are a little more pricey. You can even mount them on a movable partition (with casters) and have sound control and instrument isolation in one device.
04-30-2010, 11:59 PM
I will keep these suggestions in mind. I really like the 3/4" MDF idea because that would be very cost effective for out needs. As we are a campus organization we do not have a huge cash flow and MDF or ply is easy to get. I think one of the people was going to do the Auralex room eval sheet to see what they say but never got around to it. The RPG website has some good articles I just started poking through. Now heres a question, we have a wall made or 2x4 and cheep dry wall separating control room and "live" room. Any ideas on a cost effective building method/materials for building an acoustically insulated wall that could be outfitted near how the cement walls are?
Interesting to see a fellow ham that is knowledgeable about acoustics and is a robot guy on here. ;)
05-01-2010, 08:50 AM
The wall has got to go so you can start by making that wall skewed to change at least one parallel surface. You want to eliminate parallel surfaces in the control room as well. You want isolation between the two rooms and the only way to do that is to add mass and minimize coupling. A simple way is to reconstruct with the MDF double layer on one side of the wall. and then add two layers of drywall on the control room side. If you have room, I would suggest a 2x6 header and sole plate plate with 2x4 studs staggered so that the two sides of the wall don't touch. Be sure to add caulk to the 2x6 before you lay them in place to seal against the floor and ceiling. Caulk all openings and the entire perimeter of the wall on both sides. If you must have penetrations through the wall, don't place them back to back. i.e. electrical boxes, mic cables, speaker cables, etc. When you finish the penetration, be sure to caulk around the boxes so there is no opening. You can fill the space between the walls with insulation if you want but that adds very little to the isolation. I am guessing you are going to have a window in the wall. I would spend some real money here and get a true studio window and be sure to caulk all around when it is installed.
If wall thickness is not a concern, then building two standard walls separated by an inch is better. Mount the MDF on one and the drywall on the other. then you have no connection between the control room and studio. If you want additional isolation, then another sheet of drywall can be added to the inside of one of the wall. HVAC ducting should not be common to both rooms either. A little thought can fix this with a longer duct run and lined duct. The majority of noise inside a studio that is isolated from the outside world, comes through, or is generated by, the HVAC.
05-01-2010, 09:15 AM
Microchip sample site:
(You're allowed to get 2 samples every 30 days)
To help you make your decision, the list of PIC families:
(I'd go for a PIC18 MCU, they're designed to be programmed in C)
Make sure you chose the PDIP package, otherwise you'll have to surface mount it (instead of using a breadboard).
I chose this programmer, still haven't got it yet so I can't tell you how good it is:
05-01-2010, 08:18 PM
Thanks for the links. I'll check them out.
One last question I have. Where can inexpensive doors be bought that could work for the studio. I think the two walls will be what is done. I am assuming that the walls can be more than an inch apart? if so could the area between two walls be used for storage space?
For each individual wall, is the MDF/drywall one layer or two?
05-02-2010, 09:46 AM
The secret to isolation is mass. A door between the two areas needs to have mass to be effective. You can use an insulated steel door but it won't be as effective as a studio door which often has a layer of lead built into the door to add mass. Any studio door must have seals all the way around. Magnetic seals work well for top and sides and a strong drop seal for the bottom can be obtained from McMaster if used with a well designed threshold for sealing the floor. The High density or MDF walls should be two layers. Mount one layer horizontal and one vertical and insure that seams do not occur in both layers at the same spot. Small holes between areas sacrifice all the work you will do making heavy walls so be ready with good acoustic caulk. You want non-hardening, butyl rubber caulk that will stay flexible on parts that move like the door frame and window. Leakage between the two rooms will end up on track including the delayed program and your voices.
In order of preference for studio wall construction is solid concrete, solid concrete block, filled concrete block (sand or some other high mass material), concrete block, HDF or MDF multiple layers with separate or staggered studs, multiple layers of drywall, single layer of drywall both sides.
You can use the best techniques in the world but if you are starting in a bad space to begin with, all the money will be wasted. i.e., is the studio next to a mechanical shop or HVAC location or some other high noise environment? Is it on an outside wall with a train running by every day or is it near an airport? Is it next to the power vault? Is it under a hallway or main entrance with a lot of foot traffic above? Is it next to an elevator shaft or loading dock? I have seen people spend millions of dollars building a studio only to find out they have built over a rock formation that conducts all the traffic vibration from a freeway more than a mile away. Our school once was considering a million dollar renovation to their production theater because it was too noisey. A simple on site inspection turned up, an incorrectly installed chilled water pipe, a failed vibration isolator on an air handler that caused the flex duct joint to fail as well. The result was all the noise in the mechanical equipment was being conducted directly into the theater wall and the whole wall became a transmitter. Remember that noise traveling through a structure has very little attenuation and it travels faster through the structure than it does through air. Some problems can only be fixed by building a room within a room and isolating the inside room from the building with vibration isolators.
The walls can be separated by more than an inch and using a storage area is a great way to isolate the two wall. However, items in the storage area cannot touch both walls. The whole idea between the staggered stud design is that there can be no conduction path for energy striking one wall from being transmitted to the other wall. Russ Berger once showed me a studio wall design that was compromised by the construction guys throwing their pop cans down between the walls during lunch.
If this is your design, then two doors will be needed. If you can design the space so that the doors are not directly opposite each other, that would make the lighter steel doors perform better. How would you handle sight line between the two spaces? Do you care? We have no windows in any of our control spaces.
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