Hello audio fanatics! I am here to share my experiences with VirtualBench.
Every engineer has a hobby. Mine is building high quality audio amplifiers. I do my best to obtain unique sound performances with every new design.
For those who aren't familiar, audio designs become exponentially more complex and expensive for each level of purity you want to reach. From the AC outlet to the speaker set, there is a long way. So I need to understand what goes on with every section of my design, in order to optimize it.
Traditional instruments take time and lot of calibration before you can use them. You're lucky if your instruments can save data to a USB device. My old instruments did not. Then I used to manually take notes and use Microsoft Excel to analyze signals, create signal relationships, and more. OK, this is part of my hobby but it is really time-consuming. I could use that time for many other things. Life is too short!
A month ago, I donated my traditional instruments and started using VirtualBench. VirtualBench has all the instruments I need (Scope, Function Generator, Power Supply, DMM, and more) and takes very small footprint in my home bench.
It does not require warm up to use it and offers superior precision. Definitely a great and clean improvement! See below.
For quick measurements like checking power supplies, transistor bias, filters, and DC blocking stages, I launch the VirtualBench app that is ready to use.With the laptop with LabVIEW installed, I can automate all the integrated instruments to do a Swept Sine FRF test.
It took me few hours from first unboxing to implement an amplifier characterization test system based on shipped examples, and it takes now 30 seconds to characterize my amplifiers, compared to the previous setup that used to take about two hours with lower precision.
It is also possible to use LabVIEW signal processing and mathematics tools to implement other specific analysis.
From 5Hz to 30KHz I got sweet 29dB gain in this particular amplifier, as flat as +/- 0.5dB.
I am attaching my version of this VI developed in LabVIEW 2013.
Important: Do not forget to use an appropriate load when testing your amplifier. A precise wirewound power resistor will work (4 or 8 ohm). Be careful with heat dissipation in the load.
Hope this can help other electronic designers too. Thanks NI!