I would like to know if the 3D capabilities of an iem-type headphone are represented in the frequency response graph.
At least in an estimated way.
Do you have any method to guess it?
Thank you.
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There was a theory on head fi that a db diff between the db avg of the 3-6k range minus the 10k db resulted in a highly holographic soundstage.
While there was correlation between certain IEMs having this property and having a 3D soundstage there wasn’t enough evidence to prove it afaik. It’s especially tricky since anything in a graph above 8k is usually unreliable
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I remember a video on timeless EQing where the reviewer exposed this theory (and applied it on timeless). It was either Paul wasabi or Michael Bruce, I’m not sure.
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What I understand about post-8k measurements is that they can’t represent human hearing efficiently.
But that fact doesn’t mean the measurement can’t be consistent across iem measured, does it?
Rtings tried to create methodology to measure soundstage and imaging of over-ear and in-ear headphones. But i believe they didn’t do any methodology validation experiments so it’s mostly useless.
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Yes, I saw it. How can I get the average db of the 2-3khz zone and the 10khz zone?
Is there a website that gives me a clearer result?
Short answer: no.
Medium answer: there are things in a graph that can indicate tuning tricks used to increase the perception of soundstage. Sets with a big boost in the 3kHz region will most likely sound very intimate (in your head), while sets with a dip there will sound more open.
Decreasing the 1kHz-3kHz region as a whole and then using a late pinna gain (Japanese style) with a plateau between 3 and 6-8kHz will (especially coupled with good upper treble extension) give the perception of a live, open air performance. This is actually the basis of my target:
Long answer: no. Those tricks certainly help, and since the A4000 (pictured above) uses them and has insane soundstage, one could be forgiven for thinking a graph can predict the soundstage, but that’s not really the case.
A Blessing 2 EQed to my target, when compared to an A4000 EQed to sound like the Blessing 2 (so adding those tricks to the Blessing and taking them away from the Final) will still sound noticeably less wide than the Final will.
There are so many things we can measure that might affect soundstage: distortion, time domain stuff… Goldensound has had an amazing talk about all that on John Darko’s podcast recently. But then there are also things we can’t measure.
And then there’s fit…
Basically, it is impossible to predict whether an IEM/headphone will sound wide off a graph.
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So, as I have understood, a lower value from 1khz to 3khz will have more sensation of soundstage, right?
wrong.
It depends on so many other factors we can’t just say that a dip in 1~3KHz will result in better soundstage.
Since you do some research, take a iem that responds well to EQ, and try modifications taht should bring soundstage, then note the results down. that would be a good start for the “soundstage by fréquency response” theory.
Answered here anyway.
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My understanding is that post 8k is highly influenced by insertion depth and coupler resonance which varies from measurement to measurement. For instance look at hbb and nymz’s graphs for the Olina. Hbb’s doesn’t have a 10k dip but nymz one has a huge dip
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Exactly. Unit variance, couplers difference, insertion depth or tips just like HBB mentioned.
Squigs should be taken as a reference only and should be consistent.
Example: i always use silicone, most of the times the same ones even and always align at 8k. HBB always uses foams and inserts the deepest he can.
Our graphs might not be alike 1v1,but are consistent between our own databases. That’s what matters.
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This affects a lot. I have only three years’ experience with iems but the depth of insertion, the correct fit, the composition of the tip and the width of the tip.
Regarding the latter. Just to throw out some theory. I always use silicone tips because the foam ones bother me, if I use narrow mouthpiece tips I notice that there is more bass and a more atmospheric sound. The wide mouthpieces give me more mid-high tones and less bass.
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That is the most comon, yes. Minus the stage. Usually stage gets bigger with wider, but again, every ear is different
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Brands like BQEYZ call the narrow-bore tips “atmosphere” and say they enhance the soundstage.
I thought the wide bore tips detracted from the soundstage of the iem.
Tips also change depend on materials, wideness, lenght of the stem, etc etc etc.
That’s why you have so much choice and weird shapes.
Since humans perceive “size” of a room or space by noise decay, I would guess spectral decay plots would be one option. In those, frequency response is mapped over time instead of “statically” like a frequency response graph.
Any sort of time-domain measurement would be interesting in this regard. Throw a spike-pulse into a driver and measure how long until the noise decays. Then it is “just” (= a HUGE effort) mapping measurement results to perceived stage.
There probably has been some effort in this regard done by Engineers at Dolby, THX, Nvidia, etc. for creating virtual soundscapes. I am not aware of any whitepapers from that area though.
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