DVC Community College Classroom AV Renovation in Pleasant Hill, CA

The situation

Diablo Valley College was renovating four classrooms in its ATC building in Pleasant Hill. The AV came inside the construction contract rather than as a separate technology project. That is how most community college technology work reaches us. We held the AV scope as a public works subcontractor to Oveisi Construction, the general contractor, under subcontract D-4032.

The four rooms were not four copies of one room. One classroom has a single projection position. The other three have two each, so an instructor can put a second image up beside the first. That makes seven projection positions driven from four teaching stations. A room with two images works more like a small lecture hall than a seminar room. All four still had to work as an ordinary training room for whoever booked them.

The college was keeping its own equipment. The projectors, the rack PC in each room, the instructor laptop connection and the document camera are all owner-furnished. The projector model reads TBD on our drawings. We were designing a system to drive devices we did not supply and could not test in advance.

What made it hard

Owner-furnished sources and displays change how you design. You cannot promise a video handshake you have not tested. The switching path had to tolerate whatever laptop, adapter or projector turned up on the day.

Two of the Crestron products in our original equipment list were discontinued after the contract was signed. The DM-DGE-100 graphics engine and the HD-RX-4K-210-C-E receiver both went end of life before the equipment shipped. On a public works subcontract a part cannot be swapped quietly. Each substitution went through an RFI and a signed change order.

The rooms were also a live construction site for most of the job. Rough-in, mounting and cable pulls had to fit around the general contractor and the other trades, not the other way round.

How we designed it

We built one room standard and applied it four times, varying only the projector count. It is the same AV design and integration approach we take on any multi-room build. Each room gets a Crestron RMC4 control processor, a Crestron HD-PS402 presentation switcher, a Crestron DM-DGE-200-C digital graphics engine and a Crestron AMP-X300 four-channel amplifier.

The HD-PS402 takes the rack PC, the laptop and the document camera at the teaching station. It sends each image over Cat cable to a Crestron HD-RXC-4KZ-101 DM Lite receiver at the projector. The receiver hands the projector HDMI and carries RS-232 for power and input control. The single-projector room runs one receiver and the dual-projector rooms run two, which makes seven receivers in all. The projectors themselves stayed the college's.

Each position has a Da-Lite Cosmopolitan Electrol 123-inch 16:10 matte white screen from our projection screen range. Each projector hangs from a Peerless-AV PRG-UNV mount on an extension column and a cathedral ceiling plate. In the dual-projector rooms, a Global Caché IP2CC-P contact-closure bridge and a Crestron CEN-IO-RY-104 relay module drive the screens, so the screens drop on the same command that wakes the projectors.

At the instructor desk, the DM-DGE-200-C drives a Planar PLN2501 monitor, so the presenter can see what the room sees without turning round. Audio is Bose Professional DM5SE surface-mount loudspeakers on pan-and-tilt brackets, fed from the AMP-X300. That covers program audio from the room sources. It is not a performance system.

We kept the control processor and switcher in each room rather than centralizing them in a campus rack. With owner-furnished sources, the faults are local: a handshake, an adapter, a cable. A technician needs to see the whole chain in the room they are standing in. A per-room processor also means a fault in one classroom cannot take down the other three.

When the two Crestron parts went end of life, we did not try to source old stock. We substituted current models through RFI 5 and Change Order 1. The HD-RXC-4KZ-101 replaced the HD-RX-4K-210-C-E, and the DM-DGE-200-C replaced the DM-DGE-100. The room architecture did not change.

Equipment by room type

The parts list below follows the serial number and MAC address sheet in the closeout package, with screens, mounts and brackets taken from the pick list.

What did the network and IT side involve?

Each classroom has its own Netgear PoE+ switch. The RMC4, the HD-PS402, the DM-DGE-200-C and the room's control bridges all connect to that switch. Each room's AV network sits in the room with the equipment it serves, and campus IT deals with one switch per room.

The switch also powers devices over Ethernet. The Global Caché IP2CC-P bridges run on PoE, which keeps separate power supplies out of the ceiling.

The classroom computer network connections are separate from the AV equipment and run back to district data. In room 108 those cables were reterminated and retested on the final visit, after other work in the room had disturbed them.

The rollout

The work ran through the summer break, the only practical window on a community college campus. Rough-in and coordination with the general contractor came first, while the rooms were still a construction site. Our crew then mounted the loudspeakers and screens in all four rooms. They also re-pulled some control cable for the screen relays.

The assistive listening was the last change. The LP-4VP-072-01 transmitter sits in the room rack, and a metal rack blocks the signal. We fitted antenna extensions in all four rooms so the antenna mounts on the outside of the rack.

We trained the DVC IT team in the rooms, on the finished system. Room 108 was fully working at that point. The other three rooms still had handshake, HDCP or EDID faults with the college's own devices and adapters. That is the predictable cost of owner-furnished sources meeting a new switching path. We kept revising the Crestron control programming after training as those faults were worked through.

Support from here

The closeout package gives the college what it needs to service the rooms without us. It holds the as-built drawings, the operation and maintenance manuals, the serial number and MAC address sheet, the Crestron program files and a copy of our workmanship guarantee.

That guarantee covers the installed system for 90 days from first use at no charge. Inside that window we also broker manufacturer warranty repairs or replacements for the installed equipment. The college raises service requests as tickets through our support help desk portal, and each visit closes with a service report.

The program files matter most. When a classroom has to be reloaded, a technician works from the saved program rather than rebuilding it from memory. The serial sheet also records which parts were actually installed, including the two substitutions, so a replacement order matches what is in the ceiling.

For rooms after handover, we offer AV maintenance and managed support. Owner-furnished laptops, adapters and projectors change over a room's life, and each change is a new handshake the system has to accept. Rooms drift out of spec if nobody is watching them.

Technology partners on this project

Creation Networks, Inc. — nationwide commercial AV integrator, CTS-D certified, based in Concord, CA and Incline Village, NV. Design, engineering, programming, installation, and support from a single point of contact. Call 888-230-3661 or email sales@creationnetworks.net.