Tools for stage. Built for clarity. Browser-native, license-locked, designed for FOH, studio engineers and musicians who’d rather mix sound than fight software.
Free tools, premium tools, share-link sync. No app store. No install. No tracking. Just open a browser.
Premium tool HTML never leaks via URL.
Show Clock master ⇄ shared view in ≤3 s.
Web Share, Clipboard, Fullscreen, Wake Lock.
Platform tool or standalone embed.
The Lineup
Each one does a single job well. See it in action on its own page, or create a free account and start using it now — premium tools unlock with a one-time Gumroad key.
Free
Tempo · Metronome · Setlists
Tap to lock a tempo, build a setlist with per-song BPM and time signature, then tune up — metronome, tuner and delay-time calc all built in.
Free
Wireless · Spectrum · DE/UK/US/EU
Plan your RF frequencies before you travel. See TV-channel occupancy and find safe wireless-mic windows across four regions — so your gear’s legal and clear in every country.
Free
Pitch · Cents · Reference tones
Hz to note, note to Hz, instantly. Read the cents you’re off pitch and play an audible reference tone — quick checks without firing up a tuner.
Premium
Stage timer · Realtime crew share
A full-screen stage timer for FOH and backstage. Run it from the booth and your crew watches the same countdown on their phones — synced in three seconds, no app.
Free
SPL · LUFS · Room modes
SPL, LUFS, room modes, EQ-delay and psychoacoustics in one reference. Save a profile per venue and pull it straight back up on stage at the next gig.
Free
Click tracks · Stereo WAV
Build a click track in the browser: load a song, set tempo and offset, pick your click, and export a stereo WAV — song left, click right.
Build and share setlists with timing, notes, and changeovers. Premium tool, activating via Gumroad once available.
Professional stage plots and input lists, export-ready for production crews and venues. Premium tool, coming soon.
One USB dongle, one app. Scan the RF spectrum live, add your wireless mics and IEMs, and watch for trouble before it hits the stage.
In Three Steps
Email + password. Free tools unlock the moment you verify your email. No credit card, no trial gate, no SaaS theatre.
Buy any premium tool on checkonetwo.gumroad.com, paste the key on the platform, done. Activation is verified server-side against Gumroad — your key is bound to your account.
Open the platform on the FOH laptop, on a tablet at monitor world, on your phone backstage. Share links let crew view in real time without an account.
Built for Engineers, by an Engineer
A decade running sound for festivals and tours taught me three things — and the platform is the answer to all of them.
Tools should disappear into the workflow. No login walls when you need a setlist NOW. Free tools work after a 30-second signup. Premium tools verify instantly against Gumroad.
Show Clock has a master / viewer model: stage manager runs the timer, crew opens a share link on any phone — sync in three seconds, no app, no install.
No tracking cookies. No analytics. No data brokers. Only technically-necessary session cookies for login. Cancel anytime, your account hard-deletes — no recovery, no “soft delete.”
Premium tools are Gumroad one-time purchases. No recurring billing, no “annual seats,” no “you cancelled so your data is locked.” Your license, your tool, forever.
Squaresmile Tools is a sub-brand of Squaresmile Media — sound direction, podcast production, and digital tools for audio professionals.
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