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Measuring The High Pass Filter On A 1073 Using Fuzzmeasure - See The Sound Of Your Hardware

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Fuzzmeasure is an audio measurement tool which captures measurements and can perform calculation on and display the results of these measurements in an easy to use, slick, Mac only interface.

Fuzzmeasure is well known as a tool for acoustic measurements, it does require some know-how to interpret the results and if you are looking for a way to correct your monitors without having to understand the process then tools like Sonarworks are your best choice but if you want to be in control of the process and aren’t afraid of a learning curve then the results generated by Fuzzmeasure can be fascinating.

BAE 1073MPF

I have a BAE 1073MPF and I used this as a test bed for some equipment testing, specifically I wanted to capture and see the filter curves of the inductor-based high pass filter on this unit. I probably knew the details of this filter when I bought it but I really had no idea what it was when I started this process, if you’d asked me I’d probably have guessed at 12dB/Oct.

Setting up for a test is straightforward, it is just a case of setting the input and output channels so the sine sweep can be routed through the hardware. Once completed capturing a new measurement is as simple as clicking on a button

Graphs And Comparison

Once captured, graphs can be generated. There are templates provided for different uses but I prefer to create them manually. In this case the Frequency Response graph is the relevant one, for acoustic measurements the waterfall plots are fascinating and distortion, phase and group delay graphs are all available along with many other options.

Learning Curve

Fuzzmeasure poses more questions than it answers and I quickly realised where the gaps in my knowledge lie. If you are expecting to be able to get the results you want from Fuzzmeasure without having to understand the process then you’ll likely be disappointed. The manual is clear and complete but isn’t a primer in acoustic measurement and if you don’t know what you are doing you probably wont find the answers in the manual.

What Is The Slope Of The HPF In A 1073?

18dB/Oct - Through looking at the precise measurements I found a little variation around this figure with most of the slopes being closer to 20dB/Oct. The sight resonant bump above the corner frequency was in evidence with the 80Hz setting being noticeably flatter than the rest and the 160Hz and particularly the 300Hz setting having much more pronounced bumps.

Next on my list has to be measuring some rooms. Waterfall plots are my idea of fun, maybe that’s just me but watch this space!

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