To demonstrate my point, I’ll randomly pick and choose a few IEMs from my graph database: These concepts of resonance is in the assumption that the coupler is undamped (more on that later).Universal IEMs like FitEar demo units and 64 Audio universals tend to have short and stubby nozzles, hence resulting in shallower inserts. Deviations from the targetted resonance is expected since different IEMs have different fit.The location of the resonance bears no immediate significance, only that the measurer (me) is able to hit it consistently. Consistency and repeatability takes priority.For my measurements, I have this resonance normalised at 8kHz (whenever possible). This resonance can be controlled with a consistent measurement methodology in which the insertion depth of the IEM into the canal is made constant. This “spike” is known as coupler resonance and is typically a constant that’s independent from the IEM being measured (assuming consistent methodology). Again, the exact mechanics of this requires a whole physics lesson by itself, so here’s the simplified TL DR: when measuring IEMs, there will always be a consistent, repeatable “spike” in the higher frequencies. Now since our ear canals (and in turn, the equipment that simulate it) are essentially hollow tubes, that means that sound waves going through it will result in half-wave resonances. This part is more in reference to IEM measurements moreso than headphones, though it’s still relevant in the latter. The purpose of a FR graph is to allow you to objectively see the “signature” of a given headphone or IEM, and so is a vital (basically essential) part of your purchasing decisions as an audiophile, especially when you don’t have immediate physical access to said product. Perhaps you’re a basshead, so a roll-off below 400Hz would be a huge red flag for you. You can make use of a FR graph to see whether or not your desired frequency range is boosted or dipped. As long as you’re aware of what I’m referring to whenever I use these terms, that’s the ultimate goal of using such descriptors. Even the chart above disagrees with my classification and sees no need to specifically highlight “low mids” as its own frequency range, but that’s fine. Perhaps another would say that “upper bass” is a region that needs to be acknowledged and distinguished from the rest. Everyone has their own personal definitions and there are no strict set of rules that dictate where each frequency range ends and where another begins.Ī different person might say that the term “upper mids” only refers to frequencies between 2kHz and 4kHz. Why is this distinction important? For starters, knowing what my definitions of each frequency range are helps to interpret reviews, especially for reviewers like me who often makes references to frequency response. Though for clarity’s sake, I’ll write down my personal classifications of each frequency range: Which probably provides a better explanation than anything I can conjure up at the moment. You may have seen this famous frequency chart from the now-defunct Independent Recording Network: Such words are descriptors intended to refer to a general range of frequencies, an alternative to having to specify the exact range of numbers every single time. “Bass”? “Upper midrange”? For some of you, those might be familiar words that you’ve seen but not wholly understood. This assessment is not the most accurate since the data I’ve provided in the graph is “raw”, but more on that in the next topic. Rolls off past its initial peak, bottoming out at 7kHz where it’s roughly in line with its response at 1kHzĪnd if you’re taking this data at face value, you’d say that the Etymotic ER4S is “flat” in the bass with a boosted upper midrange, and back to somewhat “flat” treble.Peaks around 2.6kHz at a volume of roughly 12dB. “Roll-off” refers to a decrease in volume as you move up or down the frequency range.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |