Designing a paging system used to mean room dimensions in one manufacturer's calculator, a separate tap-wattage spreadsheet, and a hand sketch of the wiring. This tool pulls all of it into one browser tab.
Upload your floor plan, drag ceiling or horn speakers onto the real building, and watch SPL coverage and speech intelligibility update live. Assign zones, let it total the 70V load against your amplifier, and export a PDF proposal for the client.
It's brand-agnostic and free. It doesn't lock you into one catalog or behind a login — which is exactly where the manufacturer tools stop.
What the Paging Designer Does
Your Floor Plan, Your Speakers
Upload the actual floor plan PDF or image, set the scale, and place ceiling or horn speakers on the real building. You are not boxed into a rectangle — it handles L-shaped warehouses, corridors, and multi-room offices.
Live SPL & Intelligibility Coverage
As you place speakers, a heatmap shows sound pressure level and speech intelligibility across the whole floor. You catch dead zones and reflective trouble spots in the design stage, not at commissioning.
Amplifier & 70V Tap Budget
Every speaker carries its tap setting. The tool sums the watts on the line, checks them against your amplifier, and keeps you under the 80% loading rule. You size the right amp before anything ships.
Zones & PDF Proposal
Assign speakers to named zones and export a PDF proposal with the speaker list, zones, and amplifier recommendation. Client-ready out of the tool.
How Paging System Design Works
Good paging design isn’t just "add speakers." It’s a handful of field-proven rules that decide whether announcements are actually understood. The tool applies them for you — here they are so you know what it’s calculating.
The field rule of thumb: space ceiling speakers about twice the ceiling height apart. An 8-foot ceiling → roughly 16 feet on center for edge-to-edge coverage; tighter for full overlap and better intelligibility.
Ceiling speakers work well between 8 and 20 feet. Below 8 feet, even SPL is hard; above 20 feet you typically switch to horn speakers, which in warehouses are spaced 50 to 100+ feet apart.
The combined tap wattage of every speaker on a 70V line should stay under 80% of the amplifier’s rated output, leaving 20% headroom. The tool runs that total for you as you design.
NFPA 72 requires a minimum 0.50 average Speech Transmission Index for emergency voice systems. A comfortable design target is 0.70. The intelligibility heatmap helps you hit the margin before commissioning.
For announcements to be understood, the system has to beat background noise — typically 10 to 15 dB above ambient at the farthest listener. In spaces at OSHA’s 85 dBA action level, this drives your design.
Commercial paging uses two approaches: 70V centralized-amplified (CA), one amplifier feeding many speakers — economical and dominant in North America; and 24V self-amplified (SA), with power distributed at each speaker. This tool focuses on 70V systems.
The 70V Speakers You Can Place
The catalog is brand-agnostic — common speaker types found across the market (Atlas, Bogen, Valcom, JBL, TOA-style) instead of locking you into one product line. Drop the type you’ll actually install and the coverage numbers adjust.
70V Ceiling Speaker
The paging workhorse for offices, schools, and retail
Horn Speaker
For warehouses, outdoors, and noisy manufacturing floors
Pendant Speaker
For open ceilings and spaces with no drop tile
Surface Baffle / Backbox
Surface mount where there is no accessible ceiling
70V Taps
1/4W to 8W+ settings to balance loudness zone by zone
70V Amplifier
Single and multi-zone, sized to the total line load
What Gets Designed With This Tool
Warehouses & Manufacturing
Horn speakers over the racks, spaced 50 to 100+ feet, designed to beat forklift and machine noise by 10 to 15 dB. Drop the horns on the warehouse plan and confirm no aisle is left without coverage.
Schools
Classroom and hallway ceiling speakers for announcements, bells, and emergency notification. Intelligibility matters here — the STI heatmap helps you hit the target before an inspector measures it.
Offices, Retail & Medical
Zone paging, all-call, and background music off one central amplifier. Assign the lobby, the sales floor, and the back office to separate zones, then export the PDF for the proposal.
A Free Alternative to the Brand Tools
The ceiling speaker calculators from AtlasIED, Extron, Valcom, JBL, and Biamp are useful, but each one only works with its own catalog, and most only handle a rectangular room. JBL DSD, Yamaha CISSCA, and Bose Modeler are powerful but are Windows desktop downloads, sometimes behind a login.
At the other end, platforms like XTEN-AV and D-Tools do the full pipeline — design, proposal, bill of materials — but run $100+ a month, which prices out the small contractor. The closest free competitor, Bluesound Professional's calculator, lets you upload a plan and see a heatmap, but it's locked to Bluesound products and does no zones, no 70V taps, no STI.
This tool starts where those stop: your own floor plan, any-brand speakers, live SPL and intelligibility heatmap, a 70V tap budget, zones, and a PDF proposal — free and with no login.
Frequently Asked Questions
It depends on ceiling height and the coverage pattern of the speaker. The field rule of thumb is to space ceiling speakers about twice the ceiling height apart — for an 8-foot ceiling, roughly 16 feet on center for edge-to-edge coverage, tighter for full overlap. This tool does the math visually: drop a speaker on your floor plan and the live SPL heatmap shows exactly where coverage is even and where it drops off, so you place the right count instead of guessing.
Yes. Every speaker you place carries a tap setting (1W, 2W, 4W, 8W…). As you add speakers, the tool sums the total tap wattage on the line and checks it against the amplifier you've chosen — keeping you under the 80% loading rule that leaves 20% headroom on a 70V amp. No separate spreadsheet, no manual addition.
No. It runs in a browser tab — no account, no install, no license. Your design saves locally between sessions. That's the main difference from manufacturer tools like JBL DSD, Yamaha CISSCA, or Bose Modeler, which are Windows desktop downloads, and from XTEN-AV or D-Tools, which are paid subscriptions.
Yes. Upload a PDF or image of the actual floor plan, set the scale, and place speakers on the real building. Most free manufacturer calculators only accept room dimensions for a rectangular box — they can't handle an L-shaped warehouse, a corridor, or a multi-room office the way a real plan can.
Speech intelligibility (measured as STI, the Speech Transmission Index) is how clearly a listener can understand spoken words, not just how loud the system is. NFPA 72 requires emergency voice systems to hit a minimum 0.50 STI average; a common design target is 0.70 for comfortable margin. The heatmap estimates intelligibility across the floor so you can catch dead zones and reflective trouble spots before installation, not after a failed commissioning test.
Add up the tap wattage of every speaker on the line, then add headroom. The standard practice is to load a 70V amplifier to no more than 80% of its rated output. The tool tracks your running watt total as you place speakers and flags when you're approaching the limit, so you pick the right amp size before the purchase order goes out.
Yes. You can assign speakers to named zones on the same floor plan — warehouse floor, front office, loading dock — so an all-call and a zone page are both planned out. Most free calculators output a single speaker count for one room; almost none handle real zone design.
Commercial paging and background-music systems: warehouses and manufacturing floors (horn speakers over the racks), schools (classroom and hallway ceiling speakers plus bell schedules), offices and medical buildings, retail, and houses of worship. If it needs overhead announcements, all-call, or zoned paging, you can lay it out here.
