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Posts tagged ‘WRCT’

Grain Bin Studio Equipment

February 11, 2015


Here is a quick rundown of the equipment in the Grain Bin Studio. The speakers are Acoustic Research AR3a. The tape recorder is a four track Teac using quarter inch magnetic tape. To the right of the recorder is a hundred watt lunchbox amplifier designed by Stan Kriz. To the left is the meter head/power supply/headphone amplifier for the board. I built the mixing board by hand out of Aluminum stock. The electronics which is all rack mountable includes compressors, Stan’s 90db version of a dolby unit, reverbs, and matrixes. The center section originally held the board at the left and then later held the Teac board. the red back board is from a Three Rivers Computer booth. The tall rack holds the WRCT green machines that provided late night music. Originally it was a data logger from the Pittsburgh airport. The small rack is the six track recorder, Ampex deck and electronics. The poster is a Maxfield Parrish that hung in the original CMU studio.

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Rolling Stones

February 9, 2015


Here is a quick story about the 1969 Rolling Stones Tour. I was working for the CMU Computer Science Department in Porter Hall and living with two engineers Bob Nickau and Roland Findlay. We knew Chris Langhart from the CMU radio station WRCT and when he was picked to do the sound for the Stones tour he called on Bob to handle the amplifiers because they were using solid state amplifiers for the first time. Five days into the tour, Bob called and asked me to join the crew. He said there was a ticket for me to Phoenix at the airport for the next morning and to travel light because I was carrying the oscilloscope. Since the banks were already closed, Roland opened the Porter Hall Coke machine and lent me a few rolls of quarters for spending money. I packed my things in my attache case and left for a really fun tour. The night I arrived the Stage Manager told me he was leaving the tour to work for Country Joe and the Fish and I would be in charge of the stage miking. That was my total apprenticeship for the tour. Chuck Berry and Ike and Tina Turner were also on the show. We got very little sleep because there was only one sound crew and a new concert in a different state each night. I didn’t care, this was the tour of a lifetime. The button in the photo was our back stage pass.

2015 02 09 blog 1969 Stones Tour

Sound Reinforcement

February 7, 2015


The group at Carnegie Mellon’s WRCT radio station not only recorded classical music and produced Scotch and Soda records but also did live sound for concerts. The concert pictured was at Chatham College in 1972. Brian Rosen, who also mixed about a third of the famous Woodstock concert, headed up the sound reinforcement crew. He also worked for the CMU Computer Science engineering lab where we designed and built our mixing boards and power amplifiers. The board shown below was hand laid out with black crepe tape and then photographed and photo-etched in house and then hand soldered. Each of the nine modules was interconnected with a ribbon cable. The resulting twelve channel stereo board was only 3 inches deep and 19 inches high by 32 inches wide. The eight foot speaker columns were built in two sections, the bottom section having wheels. Each column was topped with a commercial horn speaker. The whole system was powered by four – hundred watt lunchbox amplifiers.

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Transicap Microphones

February 4, 2015


The Transicap condenser microphone was designed in the early 1970s by John Hain and Stan Kriz, engineering students at Carnegie Mellon University and members of the campus radio station WRCT. The mechanics were hand lathed by my father in his shop in Baltimore, Maryland. The diaphragm was made of vacuum spattered mylar stretched over a brass backplate mounted in an epoxy resin body. The backplate was threaded into the epoxy body so that it could be adjusted to the correct capacitive gap. The bodies were made of silver anodized aluminum. We developed special tooling for stretching the mylar and adjusting the capacitive gap. Two special black anodized Transicaps were built and subsequently dissapeared from Exhibition Hall at CMU. The core of the electronics was a small metal bodied nuvistor tube which required an external high voltage power supply. For this reason, the microphones used a four pin cannon connector between the microphone and the power supply. A standard three pin cannon connector was used between the power supply and the mixing board. We recorded Stephen Schwartz’s (Wicked) New York audition tape at CMU using Transicap microphones and a hand made mixer. My favorite story from the session was Stephen putting thumb tacks in a CMU upright rehearsal piano to make it sound like a harpsichord.

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February 3, 2015


WRCT is the campus radio station at Carnegie Mellon University and in the late 1960’s Ken Lutz, a music major, decided to do a radio show based on recitals given in the Exhibition Hall of the College of Fine Arts. Since I was a technical drama major, I was familiar with the glass ceilings of CFA and I helped Ken by hanging the microphones to record the recitals. This entailed walking out over the two story glass ceiling on the mullions between the glass panes. In the process we discovered a way from the ceilings into an old fan room off the practice hall that had been locked for years. After some research and discussions with the Dean and the head of Physical Plant, both of whom thought the room belonged to the other, we were given a key and it became the music departments first recording studio. The picture with the record turntables is the WRCT studios in Skibo. The picture with the tape recorder was our first setup in CFA. In the 1960s, WRCT was mostly run by engineers and drama students. Between them they designed and built the equipment and created the content for the shows. Both the studio console and the small battery powered mixer shown were designed and hand built by the members of WRCT. Tomorrow, I will tell you about how we designed and built our own condenser microphones.

2015 02 03 blog WRCT DJ small2015 02 03 blog WRCT Exhibition Hall

Studio in a Grain Bin

February 1, 2015


My son, David, suggested that I write a blog about the Emlenton Mill and since this is February I thought I would start by writing about sound and recording, which I love. February, you see, is the month of FAWM (February Album Writing Month). For more information check out I figure that writing a blog every day is a little like writing a song every other day, except much easier. So, welcome to the Emlenton Mill blog. I’ll try to work in the Mill along with my love of recording.

The Emlenton Mill, built in 1875, houses a mill museum, an ice cream shop, a bunkhouse hostel, an Emporium that sells antiques, crafts and books and a number of secrets. One of these secrets is a recording studio in a gain bin.

Hidden away in a converted grain bin, on the third floor of the Mill, is a recording studio control room from the 1970s. It was originally located on the music practice floor of the College of Fine Arts at Carnegie Mellon University. It was built by myself and some friends from the campus radio station WRCT. But more about that another day. The Mill has a large number of grain bins which were used to store the different grains that were processed at the Mill. They vary in size from the size of a closet to the size of a railroad box car. The grain bin we chose for the studio is a small room located just off the main area of the third floor and required very little alteration. Most grain bins are built with sloped floors so the grain would gravity feed to the center of the bin where the output chute was located. This grain bin only required a new floor to support the studio.

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