Your totally right about room treatment and why I don't spend more than the budget end of HiFi, because I know how terrible my room makes everything sound..
Ive measured a few rooms and sets of HiFi and the biggest issue I find is not the general frequency response, but room modes, they peak far more than even the frequency response from a cheap boom box. Without active EQ or a notch filter and extensive room treatment then trying to flatten out the response of a speaker is futile if you ignore the room modes. Add in transient and phase responses and you add additional challenges to getting good audio.
The improvement is so noticeable that I assume it would take a lot of resources to fix the room physically in order to achieve similar results.
I don't want to sound to enthusiastic but I'm pretty certain I'll never buy a receiver that doesn't support Dirac Live.
https://twitter.com/TLAlexander/status/1569181219446980608
The 50mm headphone drivers were globally out of stock for a year so it is safe to assume the new drivers are from a different manufacturing batch. But my hope is that the problem lies in my headphone design, and the new and old drivers are roughly the same. I don't know anything about headphone design and seemingly got lucky with the old design, so if I need to adjust my new design that's not a big deal. But if the new drivers aren't performing like the old ones, I may not be able to fix things. So next step will be to swap drivers from the old and new headphones and see if the problem follows the drivers or the headphone design.
Images of the old design as well as the link to the onshape files on this git repo:
Would you have some pointers on this?
I've been looking into this and while I've found pointers on "what to do", what's missing is where to actually find the necessary panels and how to figure if they're actually worth anything.
You can probably reduce some room resonances.
> Ultimately, this is a bandaid for a poorly treated room. If you're serious about getting a flat response curve from your monitoring room, you're far better off learning how to treat the room properly and how to position your monitors within the room for the best results.
Well, doh, but it costs zero dollars and very little effort.
In fairness, the readme does state:
> A good microphone is needed, with a wide frequency range and preferably with a flat frequency response.
By 'preferably' I assume it's implied that it can curve-fit (whatever's needed, I know next to nothing about this) to a non-flat microphone response, as long as it's known, but if it's flat then no need.
If it's unknown (and non-flat or assumed non-flat because it's cheap and doesn't make any claims about it) then that's the real problem, no point trying to do anything because it's like trying to construct a level floor with a shoelace for a spirit level.
I am lucky enough to have a spare room in my house, and set out to build a studio (an almost life-long dream) and decided that I didn't want to compromise on the acoustics and spent some time looking into the subject. In the end I built it myself with a huge amount of acoustic treatment (lost a large amount of the volume room), but more that that I enlisted the help of a professional who could do the maths and help with not just the trapping but also the panels that are needed. In the end after I built it was also tuned with DSP by the professional, has what you would normally call 4-way speakers with the subwoofers going to a higher frequency than most would consider normal and even the desk was specifically chosen to not cause a problem for the listening environment. The difference between this and something like Sonarworks (commercial software that I tried for a laugh beforehand) cannot be overstated. It's basically flat between 23hz (slightly rises at 20hz I believe) and 20Khz - we actually tuned in a more natural response curve.
It's still a home studio because it's in my home and I don't do anything commercial with it, but it's pretty much mastering grade, all with materials that are available in a builders yard and the special sauce, someone that knew what they are doing. Not everyone has the room or space to do this, but most people can build some bass traps and something to tame first point reflections.
Life has compromises. You do give up some things to build a perfect studio.
For starters, it doesn't try to achieve a phase-neutral response, because a phase-neutral response created in a room is only valid in one point of the room, and creates pre-echo artifacts elsewhere. In fact, it tries to separate the response of the speaker itself from the response of the room, by setting a threshold in the time domain, so that everything coming before it must be unaffected by the room. Then, everything coming before the threshold is corrected to a linear phase, while everything else is corrected to the minimum phase (thus making the second part of the filter purely causal).
Also, they provide an argument, citing literature, that equalizing to a flat frequency response would be wrong in a room, and thus provide an option to remove excessive treble and achieve a 1dB/octave roll-off.
Please see the details at http://drc-fir.sourceforge.net/doc/drc.html
Author here. The term "phase-neutral" simply means here that the impulse response is symmetrical and doesn't add a phase shift. It doesn't even try to neutralize the phase characteristics of the room, which is what you may be thinking. In fact the phase information from the measurement is completely discarded. Furthermore, the frequency response is averaged to get a more general and robust (less over-fitted) correction that works pretty well across the room. Try it...
It sounds like a chicken-and-egg problem to equalize speakers with an equalized microphone, but maybe microphones are simpler and can be assumed to be equalized ?
The issue is calibrating the amplitude response at a given frequency, and a tuning fork won’t help.
edit: those quartz oscillator chips have a lot in common with tuning forks.
1. http://drc-fir.sourceforge.net
I think you just found the next big thing in audiophile fads
https://en.wikipedia.org/wiki/Digital_room_correction
I don't remember the exact order but way, way, way before the $10 K USD digital audio cable snake oil, audiophiles are going to say that DRC is the second single biggest thing that can enhance the quality of your setup (the first one being which speakers you're using and how you place them). Then source quality/amp/dac. And only way further down the line, for those who believe in voodoo, $10 K digital audio cables.
0. Source material
1. Room correction DSP
2. Speakers (including subwoofers and crossover configuration)
3. Room acoustics (including positioning of speakers and listeners)
4. The human (ears, experience, expectations, ego, etc.)
All of the above are more consequential than anything else, assuming the core components are not total garbage, underspecified or malfunctioning. This includes the DAC and amplification.
Of the above list, I would place room correction at the bottom. (That still places it well above many things subjectivist audiophiles obsess over!) It is the cherry on top of a great system, not the means to achieving greatness. And it lets you get away with some things (most notably, mismatched speakers) to a greater extent than otherwise. But despite the name it can’t fix most real acoustic problems.
It can also make a system sound worse if it’s not used properly.
$10K digital audio cables are never a good idea.
I remember I went to some audiophiles house once to demo some speakers, and his "hobby" seemed to have taken over the house and common sense. He had crazy expensive audio equipment and some of the thickest cables I have seen, with the cables all suspended on little bridges.
All this in a room which was basically a square brick construction with glass windows on 3 sides, no thought to any treatment. He didn't seem to understand that the room was effecting the sound more than any DAC, Amp, Cable, or any of the other voodoo that was going on. I couldn't properly demo the speakers because of a particular standing wave. I concluded he probably had a hearing problem, he concluded he needed to upgrade a cable.
So the problem I find is that when the volume is low the bass is too low, and when the volume is high the bass is too loud. Only when I play at the same volume as the equalization was performed at do I get a good result.
By room equalization, do you mean normalizing volumes between different rooms, or...?
I'd say the worse your setup (especially your room) the more magic it does.
I did it without an individually calibrated mic though (but with a decent measuring one), wonder how much better it could be.
The results are very good. I have studio monitors and a crappy room setup, and the calibrated sound is much better. I purchased the kit with the supplied mic.
That said, the software is unstable. To the point of uselessness. It caused so many system crashes that I - very sadly, because the results are so good - just don't use it anymore.
Hoping they fix stability in later versions so I can go back to using it.
A bit sad, because it might do most for less expensive speakers and untreated rooms.
It makes a good difference to the sound - highly recommend the speakers if you are looking for a smallish set of monitor speakers that sound great and can be used very near field so you can use lower volumes.
But because of their size they don't always activate room acoustics in a crazy way, and a lot of people monitor with them fairly close so don't need them loud either further lessening the problems.
Yeah, this is why I got them really. I have a pair of Event 2020 BAS v3 but our new apartment is much quieter than the old one and I'd feel self conscious blasting them out, so was looking for something which still sounded good but worked well at low volume. I'm pretty impressed with the bass to be fair. I also tried the smaller model (iLoud Micro) but for the sort of music I like for which bass is reasonably important (techno etc.), they weren't quite there. Still impressive though
This simple insight is gold. But is it actually true? The standing wave should still pop up. Though with less energy it's probably mostly handled by the furniture.
Whatever the case, having monitor speakers sitting close avoids/lessens the issue of the first reflection point, making the higher bands sound much less "muddy". This can be improved by picking a speaker with a strong beaming characteristic. Eg 4" broadbands will bundle the acoustic wave quite strongly in the higher frequencies. Sounds muffled for bystanders outside the beam, but amazing stage and resolution for the one or two persons inside of it.
What qualifies as good enough?
Is it worth trying with consumer mics like the ones built ins on phones and laptops?
However, Sennheiser HD650 are a pleasure to wear. Even for longer periods of time. I use them with a bluetooth+USB DAC/amp (Fiio Q5; outdated) and a short cable; so I'm pretty flexible how I can use them.
It'd be most interesting to see them.
What I wanted to do was build a little headphone test dummy head. But for my relative tests I just shoved my podcast mic, Audio Technica AT2005USB up to the center of the driver on one side of the headphone. Do look at my linked tweet for those FR curves.
However this little adventure has encouraged me to consider building the little head dummy. I have some nice little capsule mics I was playing with that would work nicely, and I have a datasheet for those that probably includes a curve.
This hobby work of mine goes slowly, but I appreciate your suggestion. I will try to tune up my FDM 50mm headphone design so that it sounds at least as good as my original resin printed design, and then look at building a better characterization rig.
You can put your room dimensions into a calculator and get a rough idea of some of the try and find the modes of the room - which you want to treat, though sometimes it takes trial and error as well. But you want to treat the point of first reflection and then have bass trapping in the corners.
Don't buy that "acoustic foam" that looks like egg cartons, it's rubbish.
I use this for looks: https://www.camirafabrics.com/en/contract/inspiration/acoust...
PCs these days often still have an optical toslink, that can be used to avoid the issue.
I'll just deal with it by keeping the O2 volume low and cranking the volume on a second amp. Long term I'll just buy an element or a schiit.
I've built the O2 as well, and loved it, since for the first time I could drive the HD650; it even has enough power to properly use them on a flight (don't do it, you'll go deaf). But the form factor just isn't that great for on-the-go. Plus with the batteries installed there is no space for the ODAC, requiring a DAC solution (or a phone with a good DAC).
Give the FiiO btr5 a try instead of spending too much on a schiit, or look for similar devices from other manufacturers. A lot of them can do both USB (96kHz/24bit) and decent (LDAC) bluetooth. I could not tell a difference between a friend's BTR5 (dual ES9219C directly driving the headphones) and my Q5 (dual mono akm4490, ad8620 gain stage with dual op926 buffers when used balanced). Of course my hearing could be too damaged^^'
The Fiio options do look good. My current desktop application has me switching headphone and mic between a work laptop and personal desktop and headphone and speakers often. I use analog switches, but I'm leaning towards a one box solution in the future rather than adding more hardware. So something like a mayflower ARC mk2 perfectly covers all of my demands (including a bass boost option for my open-back headphones). I already use a USB switch with a powered USB hub, so really it would be swapping out 3 boxes and many cables for one box. The schiit hel 2 looks really great but I've read reports of 200 ms latency.
i just picked up a pair of KZ AS06 iems [1] and my listening preference is U shaped (which is how these are dialed in out of the box), but i imagine with quality hardware and e.g. 3+ dedicated, drivers it should be possible to flatten them out in an eq.
[1] https://old.reddit.com/r/headphones/comments/eqpsen/kz_as06_...
AutoEq (https://github.com/jaakkopasanen/AutoEq/) does something like this so... yes?
But targets various HRTF curves which aren't neutral or flat, and they usually aim for a Harman target of sorts, so no...
But there are some neutral-sounding curves that seek to just emulate pinna gain, so they have a ~3KHz peak which is required to 'emulate' the natural resonance of your ear, which you don't get naturally when you jam a driver all the way into it.
There's no AutoEq preset for the AS06s. Here's a representative sample targeting the 2019 Harman in-ear target for the KZ AS10s for funsies though: https://github.com/jaakkopasanen/AutoEq/tree/master/results/...
https://www.reddit.com/r/headphones/comments/afsro3/review_o...