Boys Latin School Sound System
Cafeteria School Sound System — Boys’ Latin of Philadelphia Charter School
The Challenge
Boys’ Latin of Philadelphia Charter School has one large room doing three jobs. On a normal weekday, it is a cafeteria feeding hundreds of students. On assembly days it is where the whole school gathers. On performance nights it is a stage with an audience in front of it.
Rooms like that are the hardest kind to get right. Every surface is built to be scrubbed — block walls, hard floors, a flat ceiling — which means almost nothing in the space absorbs sound. Speech energy bounces, arrives late, and stacks on top of the next word. Turning the volume up makes it worse, not better. The school needed a system that could carry a principal’s voice to the back row during an assembly, handle a microphone and a music source during a performance, and be simple enough that a staff member could run it without an audio background.
The room also had no permanent system to build on. Anything used for an event had to be dragged in, set up, and torn down.
The Design
Our systems engineer produced the design under the direction of a CTS-D certified staff member, and we modeled the room’s acoustics before specifying a single component. The controlling question in a hard, reverberant space is not how loud — it is where the sound goes. Energy that hits a bare wall or ceiling comes back as reverberation and eats intelligibility. Energy aimed at the seated audience does its job and stops.
That pointed to column array loudspeakers. A column array is tall and narrow, and it radiates in a tall, narrow pattern to match: wide coverage left-to-right across the seating, tightly controlled top-to-bottom so far less energy reaches the ceiling and the back wall. We specified a double-stacked pair of Renkus-Heinz ICX7-II mechanically steerable column arrays, one on each side of the stage on the front wall. Doubling the stack lengthens the array, which tightens vertical control further and adds the headroom the room’s size demands. The slim white cabinets also disappear against the wall, which mattered to a school that did not want boxes hanging over its cafeteria.
Column arrays are deliberately efficient in the low end, so we added a pair of Community (Biamp) VLF208LV-WI dual 8-inch compact subwoofers, wall-mounted at stage level, to give music program and walk-in playback weight without asking the columns to do work they are not built for.
For control, we specified a QSC TouchMix-16 digital mixer — 20 input channels and 10 auxes in a rack-mount frame with a built-in touchscreen. The important part for a school is what happens after we leave: the mixer can be operated wirelessly from an iPad or phone, so a staff member can walk the room and set levels from where the audience actually sits, and scenes can be saved as presets. Lunch is one recall. Assembly is another. A performance is a third. Nobody has to rebuild a mix from scratch.
Power came from two Crown XTi-series amplifiers — an XTi 2002 and an XTi 4002 — chosen because each carries onboard DSP. EQ, crossover filters, and limiters live in the amplifier, tuned to these specific loudspeakers in this specific room, and they stay there. A student can’t reach them, and a well-meaning volunteer can’t undo them.
Installation
Before anything shipped, we produced a full drawing set: rack elevation, equipment locations, wire pull sheet, functional layout, and custom wire labels. Those drawings guided the install and now live with the school’s records for any future service call — a labeled rack is the difference between a five-minute repair and an hour of tracing cable.
Equipment was received, serial-logged, and shop-tested at our facility, and the rack was built and wired before it ever went on a truck. Field work then came down to two days on site:
- A Middle Atlantic EWR-16-22 16RU wall rack was mounted stage right, with a vented front door, housing the mixer, both amplifiers, and a Furman M-8S power conditioner with sequencer that filters incoming power and brings the system up and down in the correct order.
- Five stainless-steel XLR microphone input plates and one Whirlwind MIP2S media input plate (3.5 mm and RCA) were installed along the front of the stage, so a microphone, a laptop, or a phone can be plugged in wherever an event needs it. Where no wire path existed, we ran surface-mount raceway rather than open finished walls.
- All cabling is UL-rated, Class 2/3, plenum-rated where required — 12-gauge speaker cable and 22-gauge plenum audio cable.
- Loudspeakers and subwoofers were secured to the wall with rated hardware.
- Shure BLX-R series wireless — a BLX14R/MX53 earset and a BLX24R/SM58 handheld — were racked and coordinated, giving a presenter freedom to move and a handheld for anyone stepping up to speak.
We closed with a hands-on training session covering everyday use, preset recall, and wireless microphone care, and left the school with the drawing set and registered manufacturer warranties.
Accessibility Note
Under the ADA, any assembly space with a sound reinforcement system must provide an assistive listening system. We flagged during our site visit that the cafeteria had none, and included a Williams Sound FM 457 PRO four-pack FM assistive listening system as a specified option so the school could bring the room into compliance at the same time as the upgrade. We raise this on every assembly-space project — it is the single most commonly missed requirement in school AV.
The Result
Boys’ Latin now has a permanent school sound system in its largest room. Speech is intelligible from the front row to the back wall without being punishing near the stage, because the column arrays put energy on people instead of on plaster. Music has enough low end to fill the space for performances and events. Staff runs the whole thing from a tablet, recalling a saved preset instead of guessing at faders — and nothing has to be carted in and set up before an assembly.
Every component was new and factory-sealed, installed by our own crew. No subcontractors were on this job, and the room was left clean at the end of each day.
The System
| Component | Model |
|---|---|
| Main loudspeakers | Renkus-Heinz ICX7-II mechanically steerable column arrays, double-stacked pair |
| Subwoofers | Community (Biamp) VLF208LV-WI dual 8″ compact subwoofers (2) |
| Amplification | Crown XTi 2002 and Crown XTi 4002 with onboard DSP |
| Mixer | QSC TouchMix-16 digital mixer, 20 inputs / 10 aux, wireless iPad control |
| Wireless microphones | Shure BLX14R/MX53 earset · Shure BLX24R/SM58 handheld |
| Input plates | Five stainless XLR-F wall plates · Whirlwind MIP2S media plate (3.5 mm / RCA) |
| Power | Furman M-8S power conditioner with sequencer |
| Rack | Middle Atlantic EWR-16-22, 16RU wall cabinet with vented front door |
| Assistive listening (specified option) | Williams Sound FM 457 PRO FM system, four receivers |
Does your cafeteria double as your assembly space? Most school cafeterias were built for cleaning, not for listening — and a system that works in a gym or an auditorium will not automatically work in one. We design each room from its own acoustics, install with our own crew, and train your staff before we leave.
We serve schools and districts across New Jersey, the greater Philadelphia area, and Delaware.
Request a free consultation · 1-800-650-5378 · Sales@jdsvi.com
Cafeteria Sound System FAQs
Why does my school cafeteria echo so badly?
Cafeterias are built from materials chosen for durability and ease of cleaning — block walls, hard floors, flat ceilings — and none of them absorb sound. Speech reflects off every surface and arrives at the listener a fraction of a second late, layered on top of the next word. That smearing is what makes announcements unintelligible. The fix is rarely more volume; it is controlling where the sound goes in the first place, usually with directional loudspeakers, and adding acoustic treatment where the budget and the room allow.
What kind of speakers work best in a cafeteria?
It depends on what the room does. For paging and background announcements in a room with a drop ceiling, distributed ceiling speakers give the most even coverage. For a cafeteria that also hosts assemblies or performances from a stage, column array loudspeakers are usually the better answer — they throw sound wide across the seating while keeping it off the ceiling and back wall, which is exactly what a reverberant room needs. Rooms with a stage often benefit from adding a subwoofer for music.
Can one system handle both lunchtime announcements and school performances?
Yes, and it should. A digital mixer with saved presets lets one system behave differently in different situations — a simple, limited configuration for daily announcements, and a full multi-microphone setup for a performance. Staff recalls the right scene instead of remixing the room every time.
Can staff run a school sound system without audio training?
That is the design goal. Once the system is commissioned, DSP settings live in the amplifiers where they cannot be disturbed, and day-to-day operation comes down to recalling a preset and adjusting a level or two. Systems we install can be controlled wirelessly from a tablet or phone, so staff can set volume from where the audience actually is. Every install includes a hands-on training session.
Does a school cafeteria sound system need assistive listening?
If the space is used for assemblies and has a sound reinforcement system, the ADA requires an assistive listening system, with the minimum number of receivers based on the seating count. It is the requirement schools most often miss. We flag it during the site visit and include it in the proposal so it is a decision rather than a surprise.
How much does a cafeteria sound system cost?
It comes down to the size of the room, whether it needs to support performances, and how much wire has to be run in an occupied building. A basic paging upgrade is a very different project from a full cafetorium system with column arrays, subwoofers, wireless microphones, and stage inputs. We quote every project from a site visit, with equipment and labor itemized so you can see exactly what drives the number.
Does your cafeteria double as your assembly space?
Most school cafeterias were built for cleaning, not for listening — and a system that works in a gym or an auditorium will not automatically work in one. We design each room from its own acoustics, install with our own crew, and train your staff before we leave.
We serve schools and districts across New Jersey, the greater Philadelphia area, and Delaware.
Request a free consultation · 1-800-650-5378 · Sales@jdsvi.com