100 Things #86: Listen’s Latest Generation Audio Interfaces

Traditional sound cards have drawbacks for audio testing, such as physical controls that can easily be altered, cabling errors, and the need for manual calibration. Two interfaces in our next generation of audio testing hardware: AudioConnect 2, and AmpConnect 621, fix these common problems. Both interfaces feature high resolution audio inputs and outputs, TEDS compatibility, microphone power, and internal signal routing. AmpConnect 621 features a built in amplifier and impedance measurement. AudioConnect 2 is portable and can be fully powered over USB type C.

Listen’s Latest Generation Audio Interfaces

Learn more about Listen audio interfaces

Read on for more information and technical specifications of the AmpConnect 621, AudioConnect 2. Audio interfaces can be used with a variety of test hardware including Bluetooth interfaces, turntables, accelerometers, and more. Check out all of SoundCheck’s compatibility with audio testing hardware.

Video Script:

Since SoundCheck was launched in 1995, it has become a standard as an affordable and flexible audio test and measurement system using pro audio soundcards as an audio interface .  But did you know that we also offer our own audio interfaces?

You may wonder why, since soundcards offer so many advantages, so let me share some secrets about why we designed our own hardware, and some of its lesser-known benefits.

When correctly calibrated, high-end soundcards are accurate and cost-effective, especially for high channel counts. But they do have some drawbacks, particularly when used on the production line. Common pain points with sound cards include:

  • Cabling errors – it’s easy to connect something up wrong, or to have a faulty or loose cable 
  • People may accidentally adjust the controls on the soundcard, especially in a busy lab or factory environment – if someone fiddles with your gain control mid way through a production run, you’re going to have a problem!
  • It’s not a big deal when you only have one soundcard to set up, but if you are configuring 30 or 40 production lines, it takes time to configure the channels and calibrate everything. And on top of that, your test integrity depends on this being done correctly.

Our latest generation hardware combines high resolution audio inputs and outputs with TEDS compatibility, microphone power, internal signal routing, and in some cases amplifiers and impedance measurement, to simplify your setup.

These are our two latest audio interfaces, AudioConnect 2 and AmpConnect 621. AudioConnect 2 is our ultra-portable, laptop-powered, low cost 2-channel interface. It has 2 input and 2 output channels and a headphone output. The inputs offer both constant voltage power for our SCMs, and constant current for IEPE microphones and all inputs support TEDS. It’s great for headphone measurements, or for a portable setup. AmpConnect 621 has six powered microphone inputs and two output channels, as well as a built in amplifier and impedance current sensor. This one’s great for multi-channel applications such as measurements with a 6-mic array, or when you need to drive a passive speaker or artificial mouth.

So first off, you can see that these are more than just a soundcard – we’ve put all the functionality you need in one box, with all the signals routed internally, This means that the only connection you have is one USB cable and that makes it hard to mess up your connections. So we can take a speaker testing setup that looks like this and replace it with this. And it actually costs less than all the separate components.

You’ll also notice something missing – buttons. There are no knobs or buttons on the front panel, although we do have level and overload indicators so you can be sure that everything is operating within maximum dynamic range. All control is via the software. This means that once you set your hardware configuration as part of your test sequence, no-one can deviate from that at all – either by adjusting knobs, or by incorrectly setting it up in the first place. This ensures that your test is being run correctly, and it’s particularly useful if you are relying on 3rd party manufacturers to run your tests. If you specify the hardware, software and test sequence, you can guarantee your product is tested to your exact standards with no room for error.

Another benefit of Listen hardware is fast setup with seamless plug and play operation. The calibration data is stored on the device’s firmware so when you connect your interface to SoundCheck, the system reads the calibration values automatically so there’s no need for manual calibration. The input channels also automatically populate with sampling rates, and the device self-test requires no additional cabling as all switching is internal. If you’re using TEDS microphones, you can also automatically read this data too.

So, as you can see, although we always have and always will support a wide range of soundcards, our own hardware offers some clearly defined benefits. Conversely, there are other situations, for example high channel count, where a sound card is the more cost-effective option. Our goal is test system modularity and flexibility, so sound card or audio interface – the choice is yours.