SignalScope's Room Analyzer tool employs the integrated impulse response method for calculating the acoustical parameters of a room. Schroeder reverse integration of the squared impulse response produces a decay curve, from which the Room Analyzer calculates reverberation time (RT60), early decay time (EDT), center time (Ts), clarity, and definition for the entire audio frequency band and in whole or 1/3-octave frequency bands.
The Room Analyzer also presents low, mid, and high frequency values for each parameter, as defined in the ISO 3382 standard.
- Low frequency values are averaged across the 125 Hz and 250 Hz octave bands, or across the 100 to 315 Hz 1/3 octave bands.
- Mid frequency values are averaged across the 500 Hz and 1 kHz octave bands, or across the 400 Hz to 1.25 kHz 1/3 octave bands.
- High frequency values are averaged across the 2 kHz and 4 kHz octave bands, or across the 1.6 kHz to 5 kHz 1/3 octave bands.
RT60 can be calculated based on 20, 30, or 60 dB of decay in the decay curve (T20, T30, and T60, respectively), assuming that the decay curve exhibits sufficient decay. Clarity and definition can be calculated with 50 and 80 millisecond early time cutoffs (C50, C80, D50, D80) and also with a user defined early time cutoff (Cte, Dte).
- The IR data can be taken from the Oscope or Dual FFT Analyzer tool, or it can be loaded from an AIF, CAF, or WAV audio file. The selected room parameter can also be plotted as a function of whole or 1/3-octave center frequency.
The analysis tool includes manual and automatic plot scaling, as well as a data cursor for obtaining precise information. Additionally, the current data in each tool can be saved to CSV, TXT, or MAT files. The analysis display can also be saved to a high resolution PDF file, or to an image file within the device's photo library.
The IR, squared IR, or current parameter is plotted within the data display. You can alternatively view all calculated parameters across all frequency bands of the current filter bandwidth (whole or third octave) in a table. When viewing the squared impulse response, the Schroeder decay curve is also displayed.
A data cursor may be placed within the data display with a single tap. You can move the data cursor by sliding your finger to the right or left inside the data display. When the cursor is visible, data information associated with the cursor is displayed in a small info view above the data display. It is possible to zoom in or out on the data display with a two-finger pinching gesture, and to pan the display, while zoomed in, with two fingers. A double-tap resets the display zoom and a second double tap turns off the data cursor. Cursor peak tracking can be toggled on and off with a triple tap.
- In the Squared IR plot, two cursors are available. You can optionally use these two cursors to automatically define the limits of the Schroeder decay curve integration. With this option enabled, the decay curve and room parameters are updated dynamically as you move either of the cursors with the touch or drag of a finger.
A double tap inside the vertical axis label area toggles auto vertical scaling on and off (independently for each measurement type).
Depending on the current auto-scaling state, the vertical scale of the data display may also be altered by a single-finger slide, or with a two-finger pinching gesture inside the vertical axis region (the region containing the vertical axis title and labels).
Analysis display selection controls appear near the bottom of the screen.