Set arbitrary frequency limits in SignalScope Pro 6.2

The FFT-based spectrum analyzer in SignalScope Pro 6.2 allows arbitrary upper and lower frequency bounds (Fmax and Fmin) to be specified for the spectrum display. The cursor peak track function will operate only within the specified frequency bounds. The hardware sample rate may optionally be automatically adjusted to best match the specified value for Fmax.

FFT_Plot_Limits     FFT_Options

FFT_Plot_Limits_2

An example:

A typical minimum sample rate of iOS hardware is 8 kHz. If a frequency resolution of 1 Hz is used for the spectrum, and values of 10 and 400 are specified for Fmin and Fmax, respectively, the data between 10 and 400 Hz will be plotted and the plot will be scaled to extend only from 10 and 400 Hz. If the cursor peak track function is enabled, the cursor will find the frequency of the highest magnitude between 10 and 400 Hz.

If the option to automatically adjust the sample rate based on Fmax has been selected, the hardware sample rate (Fs) will automatically be reduced to the minimum rate required to acquire data up to 400 Hz. In the case of typical iOS or USB audio input hardware, this rate would be 8 kHz. Since FFT data would then include values between 0 and 4 kHz, an additional option allows either all data (0 to 4 kHz) or only data from 10 to 400 Hz to be exported when saving FFT data to a CSV, TXT, or MAT file. Note that the DC term may be omitted from exported data when FFT data is displayed on a logarithmic frequency scale.

Also new in SignalScope Pro 6.2:

  • When “cpm” is selected for units of frequency, exported data files will include frequencies specified in cpm.
  • The nominal microphone sensitivity is properly set on the new iPhones.
  • Other bug fixes/stability enhancements, including iOS 9 compatibility.

Similar improvements have been added to version 7.2 of SignalScope. Specifying values for Fmin and Fmax in SignalScope require the Data Acquisition Upgrade, which is available via in-app purchase.

Download SignalScope 7.2

Download SignalScope Pro 6.2

 

Easy calibrated vibration measurements on Mac or iOS

digiducer_04_CE_mediumAlthough Faber Mac and iOS apps have offered excellent sound and vibration analysis tools from the start, the introduction of the Digiducer 333D01 USB Digital Accelerometer makes vibration measurement easier and more portable. When the 333D01 is connected to a Mac, iPhone, or iPad, it will be immediately recognized by our apps and ready for calibrated measurements.

For example, SignalScope Pro will recognize the connected 333D01 as an accelerometer and set the measurement units accordingly. SignalScope Pro will also automatically read calibration information from the 333D01 and establish the appropriate sensitivity so calibrated measurements can be made immediately. This works with both the Mac and iOS versions of SignalScope Pro.

Sensitivity_2_1024x1024

The 333D01 communicates with Mac OS or iOS via the standard USB Audio Class driver. Connecting to a Mac is as simple as plugging the 333D01’s cable into an available USB port. For iOS, Apple’s Lightning to USB Camera Adapter is required.* When connecting to iOS, no additional power source is required, which makes Faber apps and the 333D01 part of an ultraportable vibration measurement system.

digiducer-03

Auto-calibrated measurements with the 333D01 are supported in Electroacoustics Toolbox, SignalScope and SignalScope Pro for Mac, and in IOScopeSignalScope and SignalScope Pro for iOS.

 

Buy the 333D01 USB Digital Accelerometer

Download Electroacoustics Toolbox (Mac)

Download SignalScope Pro (Mac)

Download IOScope (iOS)

Download SignalScope Pro (iOS)

 

*Older iOS devices may require a 30-pin to USB adapter, such as the one available in Apple’s original iPad Camera Connection Kit.

iOS Audio Hardware: Stereo input via USB

If you’re looking for a way to acquire stereo input signals in apps like SignalScope Pro or IOScope, you’ll be pleased to know that you can connect a USB audio device to your iPhone, iPad, or iPod touch via Apple’s Lightning to USB Camera Adapter. Built-in USB audio support in iOS opens up a vast array of options for getting audio signals into, and out of, your iOS device. (USB audio support on iPhone and iPod touch requires iOS 7 or later.)

Compatibility

The trick is to find a device that conforms to the USB Audio Device Class specification, which essentially means that no special drivers are required when connecting the device to a host, like a Mac or an iPhone. Some device manufacturers clearly state that their product works with iOS and some do not. In general, if you find a USB audio device that does not require special drivers to work with Mac OS, then it will work with iOS as well.

Power

One thing to consider when selecting a USB audio device to connect to your iPhone or iPad is power. Some USB audio devices require an external power source, which means portability will be somewhat limited due to the need to have an A/C power outlet nearby. Other devices support USB bus power, which means they’ll draw their power from the host device (e.g. the iPhone). For portability, this would be the ideal situation since the iPhone and input device could be completely portable and operate for the life of the iPhone’s battery. However, only low-power devices can be directly powered by an iPhone or iPad, which means that a lot of otherwise compatible USB audio devices cannot be connected to iOS without some other source of power. For bus-powered USB devices that require more power, it is possible to maintain some portability with a USB battery power supply and an additional adapter cable.

A Few Examples (portable and inexpensive)

Stereo USB Audio Devices
Behringer UCA202
The UCA202 from Behringer offers very inexpensive and portable stereo input for iOS.

It features:

  • 16-bit/48 kHz sampling
  • 2 inputs and 2 outputs with RCA jacks
  • Headphone output with volume control (1/8″ jack)
  • Low power operation so it can be powered directly by an iPhone or iPad
  • S/PDIF optical digital output
Buy From Amazon Buy From B&H Photo Video
Behringer UFO202
The Behringer UFO202 is similar to the UCA202. Instead of a digital output, it offers the option to select between line-level and phono preamp input.
Buy From Amazon Buy From B&H Photo Video
ART USB Dual Pre
Another inexpensive option, which also adds mic preamps with switchable 48V phantom power, is the USB Dual Pre from ART.

It features:

  • 16-bit/48 kHz sampling
  • 2 inputs with XLR / 1/4″ combo jacks for mic preamp or line-level input
  • 2 outputs with 1/4″ jacks
  • Headphone output with volume control
  • Low power operation so it can be powered directly by an iPhone or iPad
  • Switchable 48V phantom power, powered from a 9V battery
Buy From Amazon Buy From B&H Photo Video
Adapters
Apple Lightning to USB Camera Adapter
This adapter is all that’s needed to connect a compatible USB audio device to an iPhone, iPad or iPod touch with a Lightning connector. As indicated above, if your USB device needs additional power, additional components will be needed. That will be discussed in a separate article.
Buy From Amazon Buy From B&H Photo Video
Apple iPad Camera Connection Kit
If you have an older iPhone or iPad with a 30-pin dock connector, you can connect a USB audio device with the USB adapter included in this kit. Remember that iOS 7 is required for USB audio on iPhone.
Buy From Amazon Buy From B&H Photo Video

Faber Mac apps now support USB measurement mics and accelerometer

Versions 3.8 of SignalScope, SignalScope Pro, and Electroacoustics Toolbox for Mac OS now offer built-in support for USB measurement microphones from miniDSP and Dayton Audio as well as the model 333D01 USB accelerometer from Digiducer.

Each app directly supports the miniDSP UMIK-1 and Dayton UMM-6 USB measurement microphones. Sensitivity calibration data for these mics can be downloaded automatically, just by entering the mic’s serial number. Making calibrated sound level measurements is as easy as plugging in the UMIK-1 or UMM-6, typing in its serial number, and getting started with the analysis tool of your choice (the serial number only needs to be entered once, after which the app will remember the microphone sensitivity). An internet connection is required to download sensitivity information for the microphone.

Each of these apps also directly supports the Digiducer 333D01 USB digital accelerometer, and can automatically load serial number and sensitivity calibration information directly from the device. Making calibrated acceleration measurements is as easy as plugging in the 333D01 and getting started with the analysis tool of your choice.

Various bugs and potential instabilities in each app have been corrected.

These apps all require Mac OS version 10.7 or later.

Electroacoustics Toolbox Screenshot

Electroacoustics Toolbox Screenshot

Downloads:

Download Electroacoustics Toolbox on the Mac App Store

Download Electroacoustics Toolbox trial

Download SignalScope Pro on the Mac App Store

Download SignalScope Pro trial

Download SignalScope on the Mac App Store

Download SignalScope trial

SignalScope Pro 5 adds FFT and Octave data overlays, new hardware support

SignalScope Pro 5.0 and SignalScope 6.0*, both now available for download on the App Store, add support for up to 7 FFT spectrum curves to be loaded from existing data files (CSV, MAT, or tab-delimited text files previously saved from the FFT analyzer tool). Live FFT data can be overlaid on these curves. When loaded data files include multiple channels of FFT data, one or more of those channels can be selected for display in the current FFT plot. The addition of controls for adjusting the line thickness and opacity of loaded data makes it easy to visually distinguish between live and static FFT data. The FFT analyzer also now supports fractional-octave band smoothing of curves displayed in the plot. (It is important to note this is simply smoothing of the FFT curve—it does not simulate the behavior of true fractional octave band filtering, such as that offered by the Octave analyzer tool, which is included in SignalScope Pro.)

The Octave analyzer tool** also now offers the option to load whole or 1/3-octave spectrum data from data files. Up to six curves can be overlaid on the live bar graph. Again, it is possible to select the individual channels from which to load data when multiple channels of data exist within a single file.

Another significant addition to SignalScope and SignalScope Pro is direct support for iTestMic and iAudioInterface2 hardware from Studio Six Digital, as well as the Dayton UMM-6 USB measurement microphone. The new hardware support is consistent with the additions made to SoundMeter Pro 2.3.

Screen Shot 2015-01-27 at 11.56.20 AM

Also new in SignalScope Pro:

  • SignalScope Pro 5 employs a new plotting framework for real-time data graphs and high resolution image export.
  • The black color scheme now uses black status bar, toolbar, and tab bar backgrounds.
  • Support for drawing directly to an external screen (from iPad) has been removed in favor of screen mirroring, which is handled by iOS.
  • Audio hardware input and output options are now presented from a separate toolbar button, which looks like a microphone, on iPad, iPhone 6 and iPhone 6 Plus.
  • It is possible to adjust the line thickness of live and loaded frequency response data. The opacity of loaded data can also be adjusted in order to make the live data stand out in the graph.
  • The oscilloscope time scale can now be set from the oscilloscope options menu.
  • Saving an audio file no longer causes a crash when working with large oscilloscope time scales.

Screen Shot 2015-01-27 at 11.59.04 AM

Download SignalScope Pro 5.0

Download SignalScope 6.0

* Data file export and import in SignalScope requires the Data Acquisition Upgrade, available via in-app purchase.

** The Octave analyzer tool is available in SignalScope via in-app purchase. It is included in SignalScope Pro.

RoomScope 4 with additional hardware support is now available for download

RoomScope 4.0 is now available for download on the App Store.

As with the recent update to IOScope, RoomScope now supports fractional octave band smoothing of 2Ch FR magnitude and coherence data (1/6, 1/12, and 1/24 octave bandwidths). RoomScope also adds built in support for iTestMic and iAudioInterface2 from Studio Six Digital and support for automatic downloading of sensitivity and frequency response data for the Dayton UMM-6 USB measurement microphone.

Other improvements to RoomScope include the following:

– RoomScope 4 employs a new plotting framework for real-time data graphs and high resolution image export.

– A bar graph is now used to display room acoustics parameters across octave or 1/3-octave frequency bands.

– Support for drawing directly to an external screen (from iPad) has been removed in favor of screen mirroring, which is handled by iOS.

– Audio hardware input and output options are now presented from a separate toolbar button, which looks like a microphone, on iPad, iPhone 6 and iPhone 6 Plus.

– It is possible to adjust the line thickness of plotted data.

Screen Shot 2015-01-19 at 1.03.05 PM

 

Screen Shot 2015-01-19 at 1.06.43 PM

Screen Shot 2015-01-19 at 1.07.08 PM

 

Screen Shot 2015-01-19 at 1.27.49 PM

 

 

Download RoomScope 4.0

 

IOScope 5 brings data overlays, spectrum smoothing, new hardware support

IOScope 5, which is now available for download on the App Store, employs a new plotting framework for real-time data graphs and high resolution image export. The new plotting capability also enables live frequency response data to be overlaid on up to 7 frequency response curves loaded from existing data files (CSV, MAT, or text data files exported from the Frequency tab in IOScope). An additional benefit is IOScope’s ability to smooth frequency response data into fractional octave bands (1/6, 1/12, and 1/24 octave bandwidths).

Screen Shot 2015-01-07 at 11.14.38 AM copy

Other additions to the new version of IOScope include:

– Built in support for iTestMic and iAudioInterface2 from Studio Six Digital.

– Built-in support for automatic downloading of sensitivity data for the Dayton UMM-6 USB measurement microphone.

– Support for drawing directly to an external screen (from iPad) has been removed in favor of screen mirroring, which is handled by iOS.

– Audio hardware input and output options are now presented from a separate toolbar button, which looks like a microphone, on iPad, iPhone 6 and iPhone 6 Plus.

– It is possible to adjust the line thickness of live and loaded frequency response data. The opacity of loaded data can also be adjusted in order to make the live data stand out in the graph.

Screen Shot 2015-01-07 at 11.15.09 AM copy

IOScope brings two-channel transfer function and impulse response analysis to iOS.

With IOScope, measure loudspeaker impedance, frequency response, and sensitivity. Measure a room impulse response. Tune a large sound reinforcement system, time-align a set of surround sound speakers, or optimize your home stereo. Determine the actual cutoff frequencies of your latest speaker crossover circuit, or teach your students the fundamentals of Fourier analysis of dynamic systems.

Measure frequency response magnitude and phase, coherence, and group delay. Time domain functions enable you to measure impulse response and auto/cross-correlation. IOScope includes a built-in signal generator for producing suitable excitation signals to analyze your system or device under test (DUT). The reference signal can be taken from the internal signal generator or from an external source (when using an external reference, a stereo or multi-channel audio input device, connected to the dock connector, is required).

Download IOScope 5 on the App Store.

SoundMeter Pro 2 is all about better hardware support

Like the recently released SignalScope Pro 4, SoundMeter Pro 2.0 can now uniquely identify USB audio devices attached to an iOS device and remember your settings for each audio device each time it is connected. Additionally, version 2 includes direct support for the miniDSP UMIK-1 USB measurement microphone. Sensitivity calibration and frequency response data for the UMIK-1 can be downloaded automatically, just by entering the UMIK-1’s serial number. Making calibrated sound level measurements is as easy as plugging in the UMIK-1 and typing in its serial number (the serial number only needs to be entered once, after which SoundMeter Pro will remember the microphone sensitivity).

SoundMeter Pro 2 supports manually switching between available audio inputs and outputs (i.e. if a headset microphone is connected, as well as a USB microphone, SoundMeter Pro allows you to manually switch between the built-in microphone, the headset microphone, and the USB microphone in the software without connecting or disconnecting any hardware). SoundMeter Pro 2 also supports manually switching between available microphones on devices, such as iPhones and some iPads, that have more than one built-in microphone.

Also new in SoundMeter Pro 2.0:

– Nominal input sensitivities have been updated for built-in microphones and headset inputs on iOS 8.

– On iOS 8, low, mid, and high input gain settings are available on all supported devices, for built-in microphones and headset input. Each gain setting now has an associated nominal input sensitivity. User calibrations are saved independently for each gain setting.

– A text formatting issue in MAT-file export has been corrected.

– Minor bug fixes and cosmetic enhancements.

– Apple’s Lightning to USB Camera Adapter or iPad Camera Connection Kit is required for connecting USB Audio devices to your iPhone, iPod touch, or iPad.

– SoundMeter Pro 2 requires iOS 7 or later.

SoundMeter Pro Screenshot iPhone 1

Similar features have been added to SoundMeter 6.0, although select in-app upgrades may be required (available via in-app purchase).

Download SoundMeter Pro

 

SignalScope Pro 4 for iOS uniquely identifies USB audio devices

SignalScope Pro version 4 can uniquely identify USB audio devices attached to iPhone, iPod touch, or iPad, and remember user settings for each device the next time it is connected. Direct support has been added for The Modal Shop’s model 333D01 USB digital accelerometer and miniDSP’s UMIK-1 USB measurement microphone. With the 333D01, SignalScope Pro automatically loads serial number and sensitivity calibration information directly from the device as soon as it is connected. When the UMIK-1 is connected, SignalScope Pro recognizes it and prompts the user for its serial number. Sensitivity calibration and frequency response data for the UMIK-1 can then be downloaded automatically, just by entering the UMIK-1’s serial number.

Another major new feature in version 4 is SignalScope Pro’s ability to load microphone frequency response data (FRD) and apply frequency response correction (FRC) to FFT spectrum measurements. FRD can be loaded for any input channel, for any kind of transducer (i.e. it’s not just for microphones). Sophisticated interpolation techniques are employed to generate a smooth frequency response
correction curve that matches the loaded data. This correction curve can then be applied to an FFT spectrum
of arbitrary length or frequency resolution.

SSP4 Accel and Mic

Also new in version 4:

– SignalScope Pro directly supports The Modal Shop’s model 333D01 USB digital accelerometer, and can automatically load serial number and sensitivity calibration information directly from the device. Making calibrated acceleration measurements is as easy as plugging in the 333D01. Factory calibration information is embedded in exported audio files (from the Oscope tool) when data is acquired with the 333D01.

– SignalScope Pro directly supports the miniDSP UMIK-1 USB measurement microphone. Sensitivity calibration and frequency response data for the UMIK-1 can be downloaded automatically, just by entering the UMIK-1’s serial number. Making calibrated sound level measurements is as easy as plugging in the UMIK-1 and typing in its serial number (the serial number only needs to be entered once, after which SignalScope Pro will remember the microphone sensitivity).

– Additional dB scales of 3, 6, 12, 15, and 18 dB per div are now supported by the FFT analyzer. Also, when adjusting the dB scale manually, the dB offset will always be set as a multiple of the scale so that 0 dB is always available in the vertical axis labels.

– Minor bug fixes and cosmetic enhancements.

– Apple’s Lightning to USB Camera Adapter or iPad Camera Connection Kit is required for connecting USB Audio devices to your iPhone, iPod touch, or iPad.

– SignalScope Pro 4 requires iOS 7 or later.

Similar features have been added to SignalScope 5.0, although select in-app upgrades may be required (available via in-app purchase).

Download SignalScope Pro

iOS 7 Brings USB Audio Support to iPhone and iPod touch

I’m not sure how I missed it, but I discovered this week that USB audio devices can now be used with iPhones that support iOS 7 as well as the 5th generation iPod touch (I have personally confirmed that it works with iPhones as old as the iPhone 4S and the 5G iPod touch–iOS 7 is required in order for this to work). This is great news for anyone looking to perform multi-channel or high-quality audio or acoustic analysis with something smaller than an iPad.

The iPad has supported USB audio input and output, via the iPad Camera Connection Kit, from the beginning. Until the advent of iOS 7, however, this functionality was not supported on iPhone or iPod touch. Now, a whole host of devices, ranging from inexpensive stereo USB audio interfaces to higher end multichannel interfaces, can be used with the iPhone or iPod touch you carry in your pocket. Smaller, simpler USB interfaces will draw their power directly from the iOS device. More sophisticated hardware will require some kind of additional power supply. In any case, it is important to note that the USB audio interface must support the standard USB Audio Class driver (if it works with Core Audio on your Mac, without the need to install special drivers, then it should work with your iPhone).

In order to connect a USB audio interface to an iPhone, either the 30-pin USB adapter of the old iPad Camera Connection Kit or a Lightning to USB adapter is required (depending on whether your iPhone has a 30-pin or Lightning connector on the bottom). The screenshots below demonstrate success with a Behringer UFO-202 connected to a 5th generation iPod touch and a Tascam US-800 connected to an iPhone 5S. The UFO-202 runs completely off of power from the iPod (or iPhone), so it is a completely portable solution. The US-800 requires external power.

 

IMG_0046

Measuring the inexpensive, bus-powered Behringer UFO-202 with SignalScope Pro running on the 5th generation iPod touch.

IMG_0047

Measuring the inexpensive, bus-powered Behringer UFO-202 with SignalScope Pro running on the 5th generation iPod touch.

IMG_2286

Analyzing 6 input channels simultaneously with SignalScope Pro running on the iPhone 5S. The input device is a Tascam US-800 sampling at 96 kHz.

IMG_2287

Analyzing 6 input channels simultaneously with SignalScope Pro running on the iPhone 5S. The input device is a Tascam US-800 sampling at 96 kHz.

 

If you have had any experience connecting USB audio devices to your iPhone or iPod, I would love to hear about it in the comments. What have you found that works? What doesn’t?

 

Download SignalScope Pro from the App Store.

 


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