What’s new

Calibrate from your microphone's certificate. A measurement mic ships with a sensitivity figure, and that figure is enough to read true dB SPL without owning a calibrator. Enter it once and Spektral works out the offset for you. If you have a calibrator, that route is unchanged and remains the more accurate of the two.

Load your microphone's calibration file. The response file supplied with your mic can now be imported, and the correction is applied to the spectrum itself, so the RTA and the transfer function show the room rather than the microphone. Spektral reads the frequency response files the common measurement microphones ship with, including the sensitivity figure many of them carry in the header, so a file you already have works as it is.

A calibration that cannot quietly go wrong. Certificate calibration depends on the input volume being where it was when the figure was measured, so Spektral now checks it first and says so plainly rather than handing back an offset that is wrong by however far the fader has moved.

Target curves. The transfer function target is no longer just a flat line. Choose a curve, load one from a file, or take the coherence‑weighted average of your captured positions as the target and tune the next rig to match it, with no export step at all. Spektral reads the frequency response text files other analysers write, so targets you already have work as they are. A Concert PA house curve ships with the app, contributed by a Spektral user from a large‑format concert system: roughly +11 dB at 60 Hz, flat mids, air rolled off above 10 kHz. Tolerance is selectable at ±1 to ±6 dB and the band follows the curve. A curve loaded from a file is kept: it joins the Target menu beneath the built‑in curves and stays there across launches, so a file needs importing once, not once per show, and every saved curve can be renamed or removed from its own entry.

Zoom the transfer magnitude. The magnitude plot now has a range: ±30, ±15 or ±10 dB, with the grid following at ten labelled divisions. Comb filtering that was an illegible squiggle at ±30 dB reads clearly at ±15. This replaces the grid‑spacing setting, which added lines without adding detail.

The SPL report, redesigned. A cleaner document throughout, with the session's headline figures, every rolling Leq window, a wall‑clock time axis and a data‑quality panel that says plainly what is missing before a report is used as evidence. With Limit Guard configured it states the verdict against the worst rolling window of the whole session, not merely the level at the moment you exported. Remote monitoring pages share the same design. An optional report ID carries your own filing reference, and calibration is reported as a state and a date rather than a raw offset figure.

See the PDF before you save it. Every report, SPL, RT60 and STIPA alike, now opens in a preview window first. The save panel appears once you have looked at the pages, and cancelling writes nothing.

SPL sessions record in every mode. The history graph, minimum, maximum and average used to log only while the SPL page was on screen, while the Leq figures integrated continuously. An engineer working in RTA all night got a report whose Leq covered the show and whose graph covered the few minutes they happened to be watching. The session now records whatever you are looking at.

Pause and resume an SPL session. A session can be paused between sets and picked up again where it left off, so a support act, an interval or a break between worship sets does not have to be counted as measured programme. The transport reads Start, Pause and Resume, and starting fresh is only offered when there is nothing to lose. Clearing a session that holds data now asks first. The history graph and the report read their clock from the samples themselves, so a break shows as the jump in time it was.

Refinements:

• The spectrograph fills from the bottom at its final resolution, so a fresh window scrolls smoothly from the first row instead of stretching a few giant rows across the pane.
• The SPL history graph advances left to right at a steady scale over its first quarter hour, rather than smearing a young session across the full width.
• The SPL history axis is labelled in clock time by default, matching the report. Minutes‑since‑start remains available in Settings.
• Limit Guard shows its verdict and countdown on the SPL page as well as the RTA Leq strip.
• Coherence blanking has hysteresis, so marginal regions fade out instead of flickering as the estimate wobbles.
• Captured transfer traces, their average and their phase follow the Smoothing control like the live trace, rather than always drawing at full resolution whatever the setting. Captures store the raw measurement, so ones you have already taken re‑smooth as you change it.
• A Mac returning to the SPL page after a long spell elsewhere now catches up on a remote site's backlog in one pass rather than 200 readings at a time.
• The Leq averages can be reset on demand, from the Leq strip, the SPL page or the L key, so a show can be averaged from its downbeat rather than from whenever the app was opened. Nothing recorded is affected.
• Level colours fade between zones instead of snapping, so a level sitting on a threshold reads as a blended colour rather than strobing between two.
• Gain now moves the whole RTA window rather than only its floor, so a hot low end can be brought down the plot instead of pinning itself to the top.
• SPL calibration on iPhone and iPad is available to everyone, not only to Remote Monitoring customers.
• The built‑in microphone profile for iPhone 13 mini has been measured against a calibrated reference and corrected.

Ring-Out, on every device. The Feedback Sentinel is now called Ring-Out, and it runs on iPhone and iPad as well as the Mac. Arm it from the toolbar and it watches the spectrum for a frequency that is building rather than one that is merely loud, so a bass note or mains hum cannot set it off. Each alert names the frequency and its musical note and suggests the notch, and confirmed rings collect in a list you can work through and copy to the console. On iOS the alert sits over the RTA and the list opens in a sheet.

A calibration that survives the show. Your SPL calibration now belongs to the device and the channel it was taken on, so an offset from channel 5 can never be silently applied to channel 12 on a large interface. It also follows the preamp: if the hardware reports its input gain, Spektral tracks how far the gain has moved since calibration and holds the dB SPL reading steady. And a calibration is no longer lost when an interface comes back on a different USB port, and Spektral recognises the same model and channel and reconnects it.

The SPL report, corrected and complete. Every figure in the exported report now uses one consistent calibration offset, and the report carries every Leq window Spektral measures rather than a subset.

Transfer phase, matched. Transfer phase is now drawn against the locked delay in Auto as well as Manual, and the delay compensation resolves to sub-sample precision, so the readout and the trace agree and phase above 2 kHz reads the way it does in other analysers. Phase smoothing follows the Smoothing control, weighted by coherence, and the trace lifts the pen across ±180° wraps instead of drawing a vertical line through the plot.

Leq monitor strip. The RTA gains a docked Leq strip with your chosen windows either side of the live level. When the input is not calibrated it says so plainly and reports dBFS, rather than presenting an uncalibrated number as though it were dB SPL, and Limit Guard hides itself rather than compare a dB SPL limit against dBFS.

iPhone and iPad. The SPL page has been rebuilt for phone-sized screens, the built-in microphone gets a sensible default calibration out of the box, and you can choose which microphone faces the room. Symmetric RTA gutters, spectrograph range tabs, and a toolbar that gives way gracefully as the screen narrows.

Refinements:

• Each analysis mode now opens with its own sensible defaults rather than inheriting the last mode’s.
• The RTA toolbar collapses Gain and Floor to value chips when the window runs out of width, instead of pushing controls off the edge.
• Starting pink noise from the keyboard now takes ⇧N rather than N on its own. It is the one shortcut whose result leaves the machine and arrives in the room at whatever level the PA is set to, so it takes a modifier you cannot hit by accident. Stopping is still a bare N, and the menu item always shows the key for the action it is offering. Pink noise also never starts on its own, and the button is pink while it plays.
• Transfer Function is no longer offered on iPhone and iPad. It remains on the Mac, with your phone available as the measurement mic over the wireless probe.

Fixes:

• The window now fits the screen it has to fit on, including at higher display scalings, and fullscreen exits reliably.
• The empty View menu no longer appears while the pointer tracks across the menu bar.
• The delay readout is the compensated figure everywhere it appears, and Set Ref zeroes to exactly that.
• A delay lock at a negative lag no longer fails silently.
• The SPL history graph no longer draws at the wrong offset after a calibration change.

Transfer function with just a mic. Spektral’s pink noise can now be the reference signal digitally, no loopback cable, no second input. A Mac and any single microphone (even the built-in one) can run a full transfer function with delay finding, and paired with the iPhone wireless probe as the measurement mic, the whole rig needs no audio interface at all. Choose “Use Pink Noise as Reference” in Transfer mode, then start the noise from the pink button when you’re ready. Nothing ever plays out unexpectedly. Delay readouts are tagged “· gen” because they include the output path: measure positions relative to each other with Set Ref, exactly as with the probe.

Review measurements anywhere. Transfer mode now opens your saved capture sessions with no interface connected and no noise playing: magnitude, phase, average, spread and the target band all work offline. Saved captures appear automatically in review mode, or load a session file straight from the Transfer screen.

A faster, smoother display. The whole display pipeline has been overhauled: the analyser reacts noticeably quicker at every FFT size and sample rate, smoothing and peak ballistics are now time-based so the feel never changes with settings, and the spectrograph scrolls in one continuous motion with sharper detail and corrected time labels.

Frequency zoom on the Mac. Drag a selection across the RTA to zoom into that band, drag to pan while zoomed, or pinch on the trackpad. Double-click resets, the spectrograph follows, and the status bar shows the visible range.

Sub-sample delay precision. The transfer function delay now resolves to 0.01 ms using the measured phase slope, so captured phase sits flat through the alignment band without manual nudging, matching what you’d see in other analysers, but automatically.

Captured phase display. Stored captures now draw their phase traces in the Phase/Coherence pane, in their capture colours, with hover highlighting and a coherence-gated average, to time-align speakers directly from your captured positions. Existing captures gain this retroactively.

Target band and fine grid. A new Target button shows a 0 dB line with a ±3 dB tolerance band on the transfer magnitude plot, and the grid can be switched to 3 dB steps in Settings.

Remote map, rebuilt. The satellite map now paints a true SPL field interpolated from every live measurement point, glued to the ground as you pan and zoom, with a modelled-spread mode for boundary predictions, distance rings with projected levels, and a legend that follows your caution and warning thresholds.

Refinements:

• The dB scale now appears on both sides of the RTA (Settings toggle).
• The divider between the RTA and spectrograph is draggable; double-click it to reset the split.
• Interfaces with up to 256 channels are now supported (MADI and aggregate devices).
• Closing the window now stops measurement, the mic, and pink noise cleanly. The app stays ready in the Dock and your session data is kept.
• Delay detection eases off when no usable reference signal is present, instead of working flat out.

Fixes:

• Major efficiency work aimed at older Macs: spectrograph rendering, long SPL monitoring sessions, and peak identification at large FFT sizes all cost dramatically less CPU.
• The “not calibrated” warning now shows reliably, and Limit Guard asks for calibration instead of estimating headroom from uncalibrated readings.
• Multi-position average phase is now correct for positions straddling ±180°.
• Scrubbing through spectrograph history while paused now repaints smoothly, and Snapshot works on a paused trace: the button lights and the dashed overlay appears immediately.
• Delay finding through the wireless probe now rides out network hiccups: a Wi-Fi stall discards the stale audio and carries on, instead of quietly shifting later readings by the stall’s duration.
• Switching the measurement path (interface, pink noise reference, or probe mic) now starts fresh averages immediately. The old path’s data no longer blends into the new trace for the first seconds.
• The Alignment Wizard now collects genuinely distinct measurement frames per zone, improving the reliability of its suggested delays.

Feedback Sentinel. Spektral now watches for feedback as it forms. Growing tones are flagged on the RTA before they take off, each with a suggested notch (cut and Q), and every confirmed ring is collected into a session ring-out list you can copy straight to the console.

Instant replay. Right-click the spectrograph (long-press on iPhone) to replay the audio behind any moment in the last minute.

iPhone wireless probe. Run Spektral on your iPhone and it becomes a wireless measurement mic. Its spectrum overlays the Mac RTA in violet, and in Transfer mode the new Probe Mic button uses the phone as the measurement input.

Rolling Leq and Limit Guard. Every Leq readout is now a true rolling window. The SPL overlay readouts are tappable to pick 1 to 60 minute windows, the SPL page adds a five-tile Leq grid, and Limit Guard counts down to your venue limit with an exact time-to-limit forecast.

iPhone SPL meter. The iOS app gains a full SPL Monitor mode: hero readout, rolling Leq, min, max, average and history graph.

Multi-position captures. Capture up to 12 positions (up from 6) into a redesigned sidebar, with per-position quality scoring, a coherence-weighted average trace, a position spread band, and show/hide for every trace. Sessions autosave and restore between launches.

Delay finder, rebuilt. Finds delays up to 1.4 seconds using whitened correlation with a quality gate, locks reliably on music or noise, and the impulse response view anchors the direct arrival at zero with labelled reflections and comb-filter prediction.

Refinements:

• Run and pause are now a transport pair with the active state highlighted.
• Fullscreen keeps the mode tabs as part of the app, and Ctrl+Cmd+F toggles fullscreen.
• Uncalibrated SPL readouts are labelled dBFS(A) with a clear warning until you calibrate.
• RT60 and STIPA measurement accuracy tightened after a standards audit.

Fixes:

• Major performance work: captures on screen now cost nothing while measuring, menus stay responsive during heavy sessions, and long-running sessions no longer slow down over time.
• Keyboard shortcuts no longer fire while typing in text fields or while holding modifier keys.

96kHz support. Spektral now runs at 96kHz on interfaces that support it, for finer resolution in the top end.

Refinements:

• Hide the spectrograph for a full-height RTA when you want maximum spectrum detail.
• New toggle to let the cursor free-run instead of snapping to peaks, for pinpointing an exact frequency.
• Gain and Floor, along with the Peak, Identify and Snapshot tools, now appear only in RTA mode where they apply.
• Mode tabs respond to a click anywhere on the button, not just the text.
• The sample rate now reads in kHz in the status bar.

Fixes:

• Fixed pink noise stuttering on high channel count interfaces.
• Transfer function now locks onto the built-in pink noise reliably, since the noise is correlated across channels.
• The Remote Monitoring window can now be closed with a button, not just the Escape key.

• RT60 and STIPA are now included free in the base app for every user: reverberation time and speech intelligibility measurement with no add-on purchase.
• Selectable FFT size from 2048 to 16,384 points for finer low-end resolution.
• Live input meters for the measurement and reference channels, plus a per-channel level ladder in Settings.
• Impulse response view with ETC (log dB) display, automatic reflection labelling, and comb-filter prediction overlay.

• Choose any input channels on multi-channel interfaces for the measurement and reference signals, with the routing shown in the status bar.
• Switching inputs on multichannel interfaces now works reliably in-app.
• Pink noise, RT60, and STIPA test signals follow your selected output device correctly.
• SPL calibration is stored per device, so swapping interfaces keeps each calibration.
• Weighting quick-control added to the status bar.

• Once calibrated, the RTA's dB axis reads in true dB SPL rather than dBFS.
• Delay alignment wizard for measuring relative delays between PA zones, with temperature-compensated distances.
• Multi-position transfer function captures with quality scoring and weighted averaging.

Spektral 1.6 introduced the transfer function with H1 estimator, coherence and phase, Auto-EQ suggestions, and the SPL Monitor with Remote Monitoring, and was featured on ProSoundWeb. Before that, Spektral began life as a fast, native RTA and spectrograph for ringing out PA systems, which it still is, underneath it all.