See how your speakers really sound.
Sweep plays a log sweep through your speaker and plots the response — measured from your listening position. No laptop, no audio interface, no mic stand. Just your iPhone.
How it works
Sweep
Tap once. A 20 Hz–20 kHz log sweep plays through your speaker — the Farina ESS method, exactly like the bench tools use.
Capture
A Dayton iMM-6C, UMIK, or the built-in mic records it. On-device math extracts the impulse response and plots the curve.
Compare
Overlay runs, each a new color. Scrub the curve and read frequency · dB at any point. Snap to every peak and trough.
The rig fits in your hand.
The full REW setup is a laptop, a USB audio interface, and a mic on a stand. Sweep keeps a single line-out to your amp and runs everything else from the phone in your hand — a check from your chair in under a minute, not an afternoon.
What it measures
Calibrated or convenient
The Dayton iMM-6C is the simplest — mic and sweep out on one USB-C cable. UMIK, EARS, ECM8000, and REW-style .cal files also work for capture. The built-in mic covers a quick uncalibrated check.
Runs on-device
Generating the sweep, capturing it, and computing the response all happen on your iPhone — no laptop, no cloud, nothing uploaded. Just a line-out to your amp.
Honest by design
Relative response with a time-gate isolating direct sound. The low end reflects your room — and the chart says so.
Overlay & compare
Stack measurements; each trace owns a color. See a tweak land, before and after, instantly.
Scrub any point
Drag the cursor; it snaps to peaks and troughs and reads frequency · dB right where you need it.
Real smoothing
1/24 to 1/3-octave smoothing. See the actual ripple, not a prettied-up line.
Find the room mode. Fix it. Prove it.
Two traces — before and after a sub tweak. The null at 63 Hz fills in; the 42 Hz mode comes down. Relative response, doing the one job you actually need.
Not an SPL meter. Not a REW replacement.
Sweep is the untethered scout between full REW sessions — the fast check from your chair you'll actually run. It names its limits up front, so you can trust its strengths.
Privacy
Nothing leaves your phone.
No account. No cloud. No tracking, no analytics SDK. Your measurements stay on your device — full stop.
This page serves as the privacy policy for the Sweep iPhone app.
Measure from your chair.
Download on the App StoreFree. No in-app purchases, no account.