Frequency Sweep Generator

A frequency sweep (also called a chirp signal) is a sine tone whose frequency changes continuously over time. This audio sweep tool visits every frequency in the chosen range in a matter of seconds, making it ideal for finding speaker resonances, identifying headphone driver weaknesses, mapping room modes, and measuring your own ears' high-frequency cutoff.

Log vs linear mode

The two modes describe how the frequency moves through the range:

• Log (logarithmic) — constant Hz per octave. The pitch you hear rises at a perceptually uniform rate; the lowest octave (20 → 40 Hz) takes as long as the highest (10 → 20 kHz). This matches musical interval perception and is the standard mode for speaker / headphone characterisation.
• Linear — constant Hz per second. The frequency increases by a fixed number of Hz each second, so the pitch shoots through the low end almost instantly and lingers in the high end. Useful when you want extra time at high frequencies (e.g. for tweeter or hearing-range testing) or when matching legacy lab equipment.

One-shot, repeat, and ping-pong

• One-shot — sweep once from start to end and stop. Good for clean A/B testing and for the hearing-test preset where each repeat would reset your perceptual baseline.
• Repeat — restart from the start frequency after each sweep ends. Slight discontinuity at each loop point (the frequency jumps); useful for sustained excitation of a specific band.
• Ping-pong — reverse direction at each endpoint, sweep back and forth continuously. Smooth at every boundary; great for sub-bass demos and for keeping a tone within a narrow band indefinitely.

Using the hearing-test feature

Use the Hearing test preset (30-second log sweep across the full audible range), put on headphones at moderate volume, and watch the green marker climb. The moment you can no longer hear the tone, press Mark threshold. The captured frequency is your upper hearing limit for this session — a gold marker stays on the axis so you can compare against repeat tests. Healthy young adults typically hear up to ~17–18 kHz; the upper limit drops gradually with age (and faster with noise exposure). This is a rough self-screening, not a medical diagnosis.

Speaker and headphone testing

• Identify resonances — play a slow log sweep and listen for sudden loudness peaks or "ringing" notes. Those frequencies are where the driver / enclosure / room is amplifying or holding energy unnaturally.
• Find driver limits — with the Sub-bass ping-pong preset, listen for distortion, port chuffing, or cone bottoming below your speaker's rated lower limit.
• Check stereo imaging — mono summed sweeps should appear dead-centre at every frequency. Off-centre wandering reveals channel imbalance.
• Test tweeters — the Tweeter preset (5 → 20 kHz) isolates the high-frequency driver. Audible buzzing or sudden silence indicates damage.

Room acoustics and standing waves

A slow log sweep is one of the most effective tools for diagnosing room modes (standing waves) and flutter echo. As the sweep climbs through the bass range (typically 40–300 Hz in a domestic room), you will hear certain notes swell dramatically — those peaks correspond to room dimensions resonating at half-wavelength multiples. Write down the offending frequencies, then use the wavelength calculator to confirm the matching dimension. Once identified, bass traps or panel absorbers placed at the pressure maxima (room corners and wall junctions) attenuate the modes most effectively. A ping-pong sweep across just the problem octave is ideal for repeatedly exciting a single mode while you move absorbers around the room.

Tinnitus frequency matching

Some people use a slow sweep to locate the approximate pitch of their tinnitus (ringing in the ears). Sweep slowly through the 2–12 kHz range and press Mark threshold when the sweep tone most closely matches the internal ringing you hear. This is purely self-assessment — not a clinical diagnostic tool — but the captured frequency can be useful context to share with an audiologist or hearing specialist. Use headphones and keep the volume moderate; never attempt tinnitus matching at high levels.