SpectraFoo provides all of the tools today's digital projects demand. Whether you are a live sound engineer or a studio mixer, you need the power that Foo provides. Including standards-based level metering, high-speed, high-resolution spectral analysis, the unique Phase Torch, correlation metering, triggerable waveform display, power balancing and a variety of power, envelope and spectral histories and phase analysis on any number of input or output channels, the SpectraFoo range is absolutely essential for broadcast production and critical mixing & mastering.

SpectraFoo is used around the world for analysis in mixing, mastering, acoustic analysis, live audio and electronics.

By using features like:

• Windowsets: Arrange any combination of analysis instruments however you want, save commonly used combinations and recall them on the fly via menu or keycommand
• Link groups: Selectively link controls of multiple instruments; for example, have all level meters display using the same scaling or control the frequency range of several Spectragraphs with a single slider
• Massively multichannel: Up to 24 independent analysis channels

SpectraFoo allows you to create unique combinations of analysis instruments to fit your needs, whatever they may be. One tool, many uses.

Customizable with Peak, Instantaneous, and Average traces, the Spectragraph is fast enough to create a highly detailed, animated “movie” of sonic events. Visualize your audio with the Spectragraph and see details of your recordings you've never seen before - like phase structure, overall spectral balance, dynamic range, frequency range, and low frequency roll-off.

This tool is very effective for precisely identifying frequency overlap and masking effects, such as a bass drum track and a bass track occupying the same frequency range and obscuring each other. It gives you a good picture of the rhythmic aspects of program material and is very helpful in pinpointing timing problems in dense arrangements. The Spectragram represents the power of frequency events through a color scale.

• Free: automatically retriggers on the internal clock;
• Normal: triggers the drawing trace once channel input matches your trigger settings
• Hold: triggers a drawing trace and holds the signal until rearmed
• Hold and Retrigger: same as Hold, but the trigger is automatically rearmed
• Timed Hold: same as Hold, but the trigger is automatically rearmed after the desired
  'retrigger time'
• Polarity Check: same as Hold, but displays all the data prior to the trigger point and triggers
  on either polarity and either slope
• Timed Polarity Check: rearms after the desired 'retrigger time'
• Clip Capture: same as Polarity Check but triggers when signal reaches full scale
• Timed Clip: Capture rearms after the desired 'retrigger time'

The Phase Torch can also be used as a very quick and elegant troubleshooting tool for identifying phase anomalies in studio wiring, and a number of other applications including:
• Setting azimuth on analog tape recorders
• Checking for time alignment in complex PA systems
• Frequency sensitive mono compatibility analysis
• Identifying frequency dependent phase and polarity problems (such as an out of polarity high frequency driver in a sound reinforcement system).

The Correlation History provides you with a time history of the correlation meter. See how the phase correlation evolves over time and track down specific problems while you're listening to the events. If the correlation dips every time the snare drum hits, it is very likely that the channels that contain the snare are causing the problem.

• Provides high resolution 24-bit distortion free signal generation
• Up to 9 simultaneous sine sweeps
• Pink and White noise generation
• Burst Generation
• FFT synchronized sine generation
• Direct generation to audio I/O, captures and files

This allows you to measure the properties of audio processing systems, including systems that contain acoustic elements. You can determine the amplitude and phase response of an equalizer in the presence of musical signal as easily as measuring the sound coloration of an acoustic space.

SpectraFoo provides a Delay Detection Feature to properly measure the power and phase of the response signal relative to the source signal, as the source signal must be delayed to time-align it with the response signal. The delay finder records a segment of both signals and computes the correlation of the signals with each other. By moving the cursor to the largest correlation of the two signals, you set the system delay and compensate for the measurement delay, time-aligning the two signals.

Record selections of audio into the computer’s RAM and perform incredibly detailed non-realtime analysis. All captures are referenced to the timecode of the source material. Captures may be initiated manually or can be triggered automatically, either with a level-based trigger or a time-based trigger. All recording is controlled and initiated by three basic capture modes that you may use:

1. Manual
Use manual mode to record on the fly. Click the record button to start recording and click it again to stop recording.

2. Timecode-based auto-punch
Use timecode-based auto-punch to record a segment of audio that starts at a particular time and ends at another time. This is like the auto- punch feature of many tape decks. Simply type the start and end times into the punch in and punch out fields and click the Record button. SpectraFoo will arm its auto-punch mechanism and wait until the timecode clock matches the punch-in time. It will then record until the timecode clock matches the punch-out time, and automatically stop.

3. Level-based auto-punch.
Use level-based auto-punch to start and stop recording based on the volume of the audio being monitored.This is great for capturing individual drum beats or for capturing entire songs. A specific example of the usefulness of level-based captures is when you are trying to determine the optimal placement of microphones on a drum kit. When coupled with the Auto Arm feature, level-based punches can be used to capture individual drum beats in a hands-free way, allowing you to devote your attention to placing the mic, while still benefiting from SpectraFoo’s analysis.

When Data Slicing is enabled, the realtime instruments display the data which lies underneath the current position of the cursor. If you drag the cursor around in the overview window, the realtime instruments will continuously update to reflect the current cursor position. If you replay the capture, the realtime rack will continuously update in sync with the playback.

Each time the display is updated, all of the sample in the time slice are shown. The number of samples in the time slice are determined by the I/O hardware’s buffer size. The samples are displayed starting with the first sample in the time-slice in the upper left hand corner of the instrument. Each successive sample is place under the previous one until the bottom of the column is reached. The next sample is placed at the top of the next column.

The Bit Matrix Meter is designed to work with 16-bit delivery media and only utilizes the top 16 bits of the samples in the signal. The meter takes the 16-bit samples and divides them into two groups: the most significant byte (MSB) which is the top 8 bits, and the least significant byte (LSB) which is the bottom 8 bits. For each sample these groups are then converted to horizontal (MSB) and vertical (LSB) offsets into a 256x256 pixel matrix.

Here's a typical windowset for using SpectraFoo to tweak a mix, featuring:

• Two meters showing different views of the same audio
• Spectragraph and Spectragram using link groups to ensure that the frequency and power scaling of the displays is in sync
• Independently scaled Spectragraph
• Power balance

Here's a typical windowset for using SpectraFoo to master a mix, featuring:

• Level meter using the K-Metering scale for accurate monitoring dynamic range
• Spectragraph showing instant vs. average levels
• Phase analysis
• Correlation analysis
• Detailed bit-level display

SpectraFoo Complete configured for room tuning with:

• Level meter to match source and response levels
• Transfer Function to analyze the coherence of the room, with inverted snapshot to facilitate EQ'ing
• Delay finder for setting delay times for a multispeaker audio system
• Snapshot management window

This windowset configures SpectraFoo for multizone PA tuning with:

• Multiple level meters calibrated for SPL
• Spectragraph for instant frequency analysis
• Spectragram for long decay frequency display- great for zeroing in on feedback

SpectraFoo can easily be used to test gear directly. Here we are using:

• Level meters
• Spectragram
• Signal generator
• THD Analyzer to show signal to noise and distortion

Every Metric Halo interface is tested with SpectraFoo!

To learn more about SpectraFoo in detail, you can:

Download the manual (22 Mb PDF)

Read the technotes:

Watch the tutorial videos: