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Verify the summed curve matches your mental target

After adjusting bands in the parametric EQ editor, use the applet tiles to confirm that the summed EQ response curve reflects the overall shape you intended, with the live analyzer overlay showing how real audio aligns with it.

Before you start

Steps

  1. Locate the "Aetherial TX EQ" or "Aetherial RX EQ" sub-container in the Aetherial Audio (TXDSP) parent container in the applet panel.
  2. Look at the curve area — the 110 px tall display showing a grid, the summed EQ response, the live FFT analyzer overlay, the peak-hold trace, and any active reference curve overlay.
  3. Trace the summed EQ response curve across the frequency axis. It reflects the cumulative response of all enabled bands for that path.
  4. Compare the curve shape to your intended target. Peaks, shelves, and high-pass or low-pass roll-offs appear as deviations from a flat line.
  5. If you have selected a reference curve preset in the floating editor, an amber semi-transparent overlay appears on the canvas showing the target response. You can shape your EQ bands to match this target curve.
  6. Watch the live analyzer overlay while audio passes through. The overlay shows the real-time FFT of audio on that path, letting you confirm that the shaped response is affecting the spectrum as expected.
  7. Observe the peak-hold trace (off-white line) to identify frequency bins that have reached high levels recently. The trace decays at approximately 10 dB/sec between updates, so transient resonances remain visible for a short time after they occur. The peak-hold trace operates on raw bins so peak detection is sample-accurate; display smoothing is applied separately and does not affect what the peak trace captures.
  8. Note the dashed yellow vertical lines on the canvas — these mark the radio's current TX low/high filter cutoffs (TX tile) or RX passband edges (RX tile). The applet tile receives these cutoff positions from the radio automatically and keeps them up to date as the radio's filter settings change.
  9. If the curve does not match your target, double-click the EQ stage in the CHAIN widget to reopen the frameless editor ("Aetherial Parametric EQ — TX" or "— RX") and adjust bands there.

What each control does

Control Description Notes
Analyzer / curve area ClientEqCurveWidget — minimum 110 px tall in the docked applet, locked to the path supplied at construction (Path::Tx or Path::Rx). Shows log-freq grid (20 Hz–20 kHz, ±18 dB), summed EQ response, live FFT filled-gradient analyzer (25 Hz refresh), and a peak-hold trace that decays ~10 dB/sec between updates. Dashed yellow vertical lines mark the radio's current TX low/high filter cutoffs (TX tile) or RX passband edges (RX tile). When a reference curve preset is selected, an amber semi-transparent overlay shows the target response. View-only in the applet; editing happens in the frameless ClientEqEditor. The peak-hold trace can be frozen (stops decaying) via the 'Peak Hold' button in the editor toolbar. The cutoff guide lines are draggable in the editor canvas to move the radio's passband in real time.
Summed EQ response The cumulative frequency response of all enabled bands on this path. Appears flat when no bands alter the response; shaped when one or more bands are active. Dims to grey when the EQ stage is bypassed. Persisted via ClientEqTxBands (TX) or ClientEqRxBands (RX).
Live analyzer overlay Real-time FFT of audio passing through this path. Shows idle when no audio is present, running when audio is active. Filled with a cyan gradient from 0 dB at the top fading to transparent at the bottom. Provides visual confirmation that the curve is affecting real signal.
Peak-hold trace Off-white line drawn on top of the live analyzer. Each frequency bin holds the highest level observed, then decays at approximately 10 dB/sec. Stops decaying when Peak Hold is checked in the floating editor. Operates on raw bins so peak detection is sample-accurate; visual smoothing of the peak trace is applied separately in display processing. Helps identify resonances and harsh peaks while tuning. Visible in both the applet tile and the floating editor.
Peak Hold Toggle button in the floating editor header strip. When checked (amber background), the peak-hold trace stops decaying — every frequency bin's highest observed level is held until the button is toggled off. Located in the floating editor only, not in the docked applet tile. Toggle off to resume normal decay.
Smoothing Combo box in the floating editor header strip. Applies fractional-octave power-averaging to the analyzer trace for display — does not affect EQ math. Options: Off (1/96), 1/24, 1/12, ⅙, ⅓. Lower fraction = smoother (⅓ is most smoothed; 1/96 is effectively off). Smoothing runs after the peak-hold update each frame so both the analyzer and peak-hold buffers reflect the current frame before smoothing is applied. Shared between TX and RX editors. Setting key: ClientEqSmoothingFraction. Tooltip: 'Fractional-octave smoothing applied to the analyzer trace. Lower fraction = smoother (⅓ = most, 1/96 = off). Affects display only — EQ math is unchanged.' Located in the editor header strip (floating editor only).
Reference curve preset Combo box in the floating editor header strip. Selects a target frequency-response curve overlay to guide EQ shaping. Options: Off (no overlay), AT&T 1959, Heil DX, Astatic D-104, Shure 444, Heil HC-5. The selected curve draws as an amber semi-transparent line on the canvas. Each preset is a digitised reference (point-to-point in log-freq × linear-dB space) representing a classic microphone or communications target. Does not affect audio — visual guide only. Persisted per path: ClientEqTxReferencePreset / ClientEqRxReferencePreset.
Filter family Combo box in the floating editor header strip. Selects the mathematics used for HP and LP cascade filters. Options: Butterworth (maximally flat passband), Chebyshev (steeper rolloff with 1 dB passband ripple), Bessel (linear phase / gentler rolloff), Elliptic (steepest transition with ripple in both bands). Default: Butterworth. Applies only to HP and LP filter types. Peak and shelf bands use their own fixed 2nd-order topology regardless. Persisted separately per path: ClientEqTxFilterFamily / ClientEqRxFilterFamily.
Reset Push button in the floating editor header strip. Resets all bands to the default 10-band template, restores the default band count, and resets the filter family to Butterworth. Saves immediately. Tooltip: "Reset all bands to default values". Located in the floating editor only.
Output Fader Vertical combined fader + level meter on the right edge of the floating editor. Drag to set post-EQ master gain; scroll wheel adjusts in 0.5 dB steps; double-click resets to 0 dB. Click the value display at the bottom to edit the dB value directly: type a number, press Enter or click elsewhere to commit (range -36 to +12 dB). Press Escape to cancel editing. Range: -36 to +12 dB. The level bar behind the handle shows the smoothed post-EQ peak in real time with the same green-amber-red gradient as the Tube level meter. Persisted separately per path: ClientEqTxMasterGain / ClientEqRxMasterGain. Tooltip: "Output gain (dB). Drag to set, wheel for fine step, double-click to reset to 0 dB. Click the value to type a number." Gain range is linear 0.0 to ~4.0; the scale labels run from -40 to 0 dB. Located in the floating editor only — not in the docked applet tile.
Filter-type icon row A row of 8 custom-painted icons (one per band slot) at the top of the editor canvas area. Each icon draws the current filter shape (peak bell, shelf ramp, HP/LP slope) in its band's palette colour. Click an icon to cycle through the filter types for that band; clicking also selects the band, highlighting its handle on the canvas and its column in the parameter row. Located in the floating editor only. Icons dim to 35 % opacity when the band is bypassed. Implemented by ClientEqIconRow.
Parameter text row A row of 8 text columns (one per band slot) below the canvas showing each band's Freq, Gain, and Q values. Values update live during canvas drags. Clicking a column selects that band. Right-click a column to open the numeric entry popup, where you can type exact values for Freq, Gain, and Q; entries are committed on Enter, persisted immediately, and the canvas and icon row refresh. Located in the floating editor only. Implemented by ClientEqParamRow.
Filter cutoff guide lines (TX / RX) Dashed yellow vertical lines overlaid on the canvas at the radio's current TX low/high filter cutoff (TX tile) or RX passband edges (RX tile). Hovering near a line changes the cursor to a horizontal-resize arrow. Dragging a line in the editor moves the radio's corresponding filter cutoff in real time. The applet tile receives updated cutoff positions automatically whenever the radio's filter settings change. Dragging the TX cutoff guides emits cutoffsDragRequested(Tx, lo, hi), which MainWindow forwards to TransmitModel. Dragging the RX guides writes to the active SliceModel. Pass 0 for an edge to suppress that guide.
Audio band-plan strip A 14 px strip permanently visible at the bottom of the EQ canvas. Shows E-SSB / SSB / AM-FM modulation regions as a frequency reference. Cursor interaction in this area is excluded from band-handle hit-testing.

Tips

  • The applet tile is view-only. No editing happens here. All band changes must be made in the frameless editor opened from the CHAIN widget.
  • There is one tile per side. "Aetherial TX EQ" is locked to the TX path; "Aetherial RX EQ" is locked to the RX path. They do not share a selector.
  • Use Peak Hold in the floating editor to freeze the peak-hold trace while you tune a band. This makes it easier to see whether a resonance has been reduced without the trace decaying away between adjustments. Toggle Peak Hold off when you are done to resume normal decay.
  • Use Smoothing in the floating editor to reduce visual noise in the analyzer overlay when working in dense spectrum environments. Set it to Off (1/96) when you need to see narrow-band detail. Smoothing affects the display only — the underlying EQ math and peak-hold detection are not changed.
  • Use the Reference curve preset combo box to select a target frequency-response curve overlay. This draws an amber semi-transparent line on the canvas as a visual guide — it does not affect the audio. Choose from classic microphone response curves (AT&T 1959, Heil DX, Astatic D-104, Shure 444, Heil HC-5) or set to Off to hide the overlay.
  • If the curve appears flat but you expect shaping, check whether the EQ stage is bypassed. A bypassed stage does not apply its bands to the audio path even though the curve display may still render the shape. See Bypass the EQ stage from the chain.
  • Use Reset in the floating editor to return the EQ to a known starting point. All bands, band count, and the filter family are restored to their defaults and saved immediately.
  • The dashed yellow filter cutoff guide lines in the applet tile update automatically as the radio's filter settings change. No manual refresh is needed.
  • To enter an exact numeric value for the Output Fader, click the dB value at the bottom of the fader. The display changes to a plain number with a cyan border. Type the desired value and press Enter or click elsewhere to commit. Values are clamped to the -36 to +12 dB range. Press Escape to cancel the edit and revert to the previous value.
  • Right-click a column in the parameter text row to open a numeric entry popup for that band's Freq, Gain, and Q values. Enter values and press Enter to commit; changes persist immediately and the canvas and icon row refresh to show the updated state.
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