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Audeze LCD-24 Review (Headphone)

Robbo99999

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I see the spirit of an open exchange of ideas and mutual respect is alive and well on ASR recently.

As, seemingly, is misplaced hubris and condescension.
(Depends on your perspective (& intentions of involved parties))
 

Rthomas

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I do. Company has sent me a couple.


I think you will be pleasantly surprised by the tuning upgrades done to the 2021 LCD-X and LCD-XC.

They've mostly filled that hole in the upper mids/lower treble by changing the pads. The 2021 LCD-XC I tried was the most ''correct'' sounding Audeze and EQ was optional. Hopefully they upgrade the rest of the lineup.
 

Francis Vaughan

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I do. Company has sent me a couple.

I wonder if there is the possibility of looking at their Reveal+ software plugin as well when doing the reviews?

They make some interesting claims about building a personalised HRTF, which cuts right to the point of EQ. Understanding what is on offer and its success in achieving the goal would be really interesting and pertinent.

I would imagine there may be some issues in getting the audio chain to work with the analysis, but if it isn't a total disaster would seem to be worth the effort.
 

Francis Vaughan

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I think you will be pleasantly surprised by the tuning upgrades done to the 2021 LCD-X and LCD-XC.
Well they certainly understand extracting additional money from those that have it. For both models there is a "creator package" and "premium package"
The only difference is the addition of a 1/4" to 1/8" adaptor, a balanced cable (in addition to the standard single sided cable) and an upgraded case.
For $500. Goodness. Even more strange when the web price for the standard case replaced is $150, additional cable is $150 and the adaptor is $20. So a nice case for $480? That values the case getting on for half that of the headphones. It had better be something pretty damn special.

Any company that sells expensive premium cables drops a notch in my estimation. Whilst I understand that they are there to make money, and there is a market demand they might as well make money from as opposed to someone else doing so, having $600 cables on offer diminishes them in my eyes. It diminishes the value of their core product.
 

richard12511

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This is starting to look like the headphone I wish more manufactures would manufacture. IMHO applying any HRTF compensation curve in the electromechanical domain inside the headphone is simply the wrong place to do it. The tools available to the designer are blunt and primitive. But it means that the HP is backward compatible with existing equipment. So they are easy to sell.

But it is 2021 according to my calendar. DSP is near free and common. We are already accepting that use of EQ is not just useful, but near mandatory. So stop messing about and put the entire HRTF in the EQ. This frees the designer of the HP from messing about compromising the design trying to achieve the HRTF with poorly suited tools. Indeed such freedom means they can probably look for improvements that were previously ruled out due to the constraints needed to create a HRTF. It is putting the HRTF into a domain where it can be achieved without compromise, and finally, allowing the user to tune the HRTF to their own physical proportions.
The Harman curve is a compromise averaging across an average human head and torso. If you are much bigger or small than this average the Harmam curve is not optimal for you. So you could do better.

It it wasn't so expensive I would seriously consider this HP as my next purchase. I don't think Beelzebub allows double dipping.

Man, what a great idea! Truly! One of the best ideas I've heard.

But, it has me wondering...why don't headphones just go active? With loudspeakers, there is definitely an advantage to going active (better crossovers, different driver possibilities, dsp), but with headphones it seems like the advantage is even greater(since they need way more DSP).

I'm guessing there is a practical reason that I'm not seeing, but it seems like one could design the worlds best headphone by aiming for a dead flat response with very little distortion(just like this HP), and then applying the HRTF via DSP. They could even have multiple presets at the press of a button to flip between different preference curves based one's bass preferences.

It's kinda frustrating for me and my use case. I realize that it's easy to apply DSP through Roon or EQAPO or whatever in a desktop environment, but if I'm at home, I'm listening to loudspeakers. If I'm listening to headphones, it's because I'm on the run, and none of my mobile music sources(Tidal, Qobuz, Spotify) support PEQ. For the most part I'm stuck with horribly wrong tonality when listening to HPs :(.

Is it too hard to fit the amp and DAC inside while keeping weight down? Personally, I wouldn't mind a slightly heavier headphone if it means I can have EQ.
 
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amirm

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But, it has me wondering...why don't headphones just go active?
Big problem: power. You need batteries which then requires charging. You also need amplifiers. In other words, you will be building a wireless headphone :).
 
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amirm

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I think a simple solution is what Audeze is already doing: providing EQ profiles for upstream processing. Roon has presets for most of their headphones already and in my testing of the LCD-X, it does the right thing.
 

MayaTlab

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I'm guessing there is a practical reason that I'm not seeing, but it seems like one could design the worlds best headphone by aiming for a dead flat response with very little distortion(just like this HP), and then applying the HRTF via DSP.

If we're strictly speaking of HRTF I can think of several issues :
- if proven that generic HRTFs can’t be effective at sound localisation, gathering the anatomical data to turn it into an individualised HRTF profile.
- headphones measuring differently on your head than on a third party test rig for various reasons (lateral and vertical positioning variations, clamping force / pad compression / pad wear, the anatomy of your ear, etc.).

In regards to the former we’ve already seen quite a few attempts at using visual cues to derive individualised HRTFs, such as using user-generated photos or videos (Sony, Genelec unless I’m mistaken ?). I’m not sure that this provides enough data points to work effectively. But given enough data algorithms seem quite adept at generating individualised HRTF profiles (there are countless articles on the subject,I’ve also seen a few videos on the subject such as this one :
)

Here I think that Apple is in quite a unique position. With Face ID on their iPhones they can already gather quite a bit of data on the user’s head and perhaps the system could be used more accurately than a simply camera system for photos of one’s ear. But maybe even better, perhaps Apple could embed the sensors within the earcups themselves.

Quite a few of Apple’s patents released in the four years prior to the APM’s release show that they envisioned the use of various types of sensors to make a more or less precise image of the user’s ears within the cups. The most detailed patents mention the use of capacitance sensors for fairly simple applications (simply recognising the rough shape of the ear to make the headphones left / right reversible for example). For example : https://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=/netahtml/PTO/srchnum.html&r=1&f=G&l=50&s1="20200280785".PGNR.&OS=DN/20200280785&RS=DN/20200280785
Screenshot_2021-01-08_at_10.21.55.pngScreenshot_2021-01-08_at_10.22.03.png
Unfortunately none of that happened in the final product :D. But perhaps in the future we may see an increasing amount of sensors within the earcups and headphones may be able to provide an increasingly higher res image of our ears.

In regards to the latter the DIY probe / tube microphone that I’m making has been quite helpful in characterising this issue above the range where in concha microphones (of this type for example : https://www.soundprofessionals.com/cgi-bin/gold/item/SP-TFB-2) start to become useless. It’s based on this video from David Griesinger :
. Although at this point it deviates quite a bit from it.

I’m now starting to get quite confident about using it for comparative evaluations up to around 10kHz. During the same measurements session I like to bookend it by measuring a pair of known headphones with a low positional variation to make sure that the probe didn’t move to any signifiant degree during the session. This is the typical sort of variation that you’ll see, here with a HD650, normalised at 505Hz (so basically within 1dB and the variation at higher frequencies is quite linear to begin with), between the very beginning and the end of a 2 hours session, after god knows how many headphones changes and seatings :
Screenshot 2021-06-12 at 07.04.00.png
Across different sessions (on a different day) the variation tends to be higher than I’d like, essentially because of the probe’s position within my ear canal. Here is a difference between a session yesterday and one a couple weeks ago, still with the HD650 :
Screenshot 2021-06-12 at 07.05.26.png
I’m getting better at consistently locating the probe but it’s a work in progress.
That being said, in different sessions, regardless of the exact absolute numbers, comparing my HD650 to my HD560S yielded very similar comparative results (HD560S in blue, HD650 in red), two different sessions a week appart :
Screenshot 2021-06-12 at 07.10.13.png
So I think that it’s a pretty solid method for comparative evaluations, regardless of the probe’s exact position within my ear canal. It's not rock solid mind you, and certainly should not be used to assert things such as "on my head, headphones X has 3.765dB more than headphones Y at 4327.3Hz", but just to assess trends in a somewhat loose way ("at 7300Hz or so, headphones X tend to be 2.5-3dB higher than headphones Y").

So, in regards to how headphones vary on your head vs. test rigs measurements, something quite simple to do, since comparative results are quite effective with this probe, simply is to apply Oratory1990’s (or others) presets and measure. This is how the HD650 (red) and HD560S (blue) measure on my head with Oratory’s Harman presets, first with the DIY probe mics and then with in-concha mics (valid for comparative results up to around 3 kHz or so with these large open over-ears ?) - solid traces with Oratory’s EQ, dotted traces with no EQ :
Screenshot 2021-06-12 at 07.26.49.png

Screenshot 2021-06-12 at 08.00.45.png

The remaining differences are still audible. And in fact it’s debatable whether or not applying the preset made them sound closer to each others past a few kHz. In the 5-6.5kHz region it actually made them diverge more :D (well if you normalise at 500Hz that is).
And remember that we’re talking here about two Sennheiser open back passive headphones with fairly low seatings variation and which already adhered quite well to the target.
With other headphones the differences when applying Oratory’s presets may be higher.

Another illustration of a typical problem. Apple decided to reinvent the yoke mechanism with the AirPods Max and this is only bringing a ton of problems to it as their solution applies all clamping force at the top of the earcup, and then tries to re-balance the pressure and seal the bottom by spring loading the cups. On my head with large temples and jaws but a narrow neck this results in the pads being a lot more compressed at the top front than at the rear bottom (but I'm still getting a good seal). This is how the APM varies between when I let them naturally sit on my head (green), and when I deliberately apply pressure at the bottom rear of the cups (orange), with both types of mic :
Screenshot 2021-06-12 at 07.34.12.png

Screenshot 2021-06-12 at 07.35.14.png

You notice however that the FR curve below 800hz or so is invariant. That’s because in that range Apple uses the inward facing mic to adjust the FR in real time to reach a precise target (what they call Adaptive EQ). Other ANC headphones do this as well (Bose, Sony).
But above that ? Significant variation (the APM isn’t the worst I have at home in that regard BTW). Someone else may get a result closer to one of these traces depending on their head shape.

Other than designing headphones better for low variability I’m not sure what would be the most effective solution. At lower frequencies headphones with an open front volume tend to be quite insensitive to seal variation, but not necessarily to pads compression. ANC headphones seem to have the best solution, using their inwards facing mic for real-time adjustments. Above that perhaps the same sort of sensors that could be used to gather anatomical data within the headphones’ earcup could be used for real time compensation as well ?

Anyway, if all of that is happening, you just can’t plug in a generic, baked in HRTF preset on a pair of headphones that may very well measure differently on your head than on a test rig and hope for the best. I have a feeling that we may really need both these problems tackled first to get truly effective sound virtualisation on headphones.
 
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Jimbob54

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Man, what a great idea! Truly! One of the best ideas I've heard.

But, it has me wondering...why don't headphones just go active? With loudspeakers, there is definitely an advantage to going active (better crossovers, different driver possibilities, dsp), but with headphones it seems like the advantage is even greater(since they need way more DSP).

I'm guessing there is a practical reason that I'm not seeing, but it seems like one could design the worlds best headphone by aiming for a dead flat response with very little distortion(just like this HP), and then applying the HRTF via DSP. They could even have multiple presets at the press of a button to flip between different preference curves based one's bass preferences.

It's kinda frustrating for me and my use case. I realize that it's easy to apply DSP through Roon or EQAPO or whatever in a desktop environment, but if I'm at home, I'm listening to loudspeakers. If I'm listening to headphones, it's because I'm on the run, and none of my mobile music sources(Tidal, Qobuz, Spotify) support PEQ. For the most part I'm stuck with horribly wrong tonality when listening to HPs :(.

Is it too hard to fit the amp and DAC inside while keeping weight down? Personally, I wouldn't mind a slightly heavier headphone if it means I can have EQ.

For mobile, Android or Apple? If Android- look at Wavelet app- applies DSP for most headphones via the AutoEQ repository. Definitely works for Spotify, not sure about other player apps (Doesnt work for Amazon for eg). Play music on spotify, open Wavelet , search for HP model, off you go. Can tweak after with a 10 or 12 band GEQ.
 

Phos

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So, bit of an aside, the name "Audeze" is a play on "Odyssey" in terms of how it's pronounced.

But more to the subject, In don't think person to person HRTFs being different is a good reason to bake a specific HRTF into the physical headphone, actually the opposite, that it makes more sense to make it variable. I don't think any mention of individualized HRTFs is complete without me bringing up this video:

Basically, individualized HRTF isn't a new idea, Apple's just the first company to implement it at scale.

Realistically, there probably isn't enough spacial information retrievable from a stereo recording to exceed what an EQ is able to do, so I imagine a full fat HRTF profile really only helps if you are talking about ambisonic recordings. Of course this also ignores tracks that are already mixed for headphones which complicates matters even more.

Fun aside: The spherical harmonics used in Abisonic recordings look exactly like electron orbits. I suppose that shouldn't really be surprising, it is just higher order spheres, writ large and small.
 

Nathan Raymond

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Man, what a great idea! Truly! One of the best ideas I've heard.

But, it has me wondering...why don't headphones just go active? With loudspeakers, there is definitely an advantage to going active (better crossovers, different driver possibilities, dsp), but with headphones it seems like the advantage is even greater(since they need way more DSP).

I'm guessing there is a practical reason that I'm not seeing, but it seems like one could design the worlds best headphone by aiming for a dead flat response with very little distortion(just like this HP), and then applying the HRTF via DSP. They could even have multiple presets at the press of a button to flip between different preference curves based one's bass preferences.

It's kinda frustrating for me and my use case. I realize that it's easy to apply DSP through Roon or EQAPO or whatever in a desktop environment, but if I'm at home, I'm listening to loudspeakers. If I'm listening to headphones, it's because I'm on the run, and none of my mobile music sources(Tidal, Qobuz, Spotify) support PEQ. For the most part I'm stuck with horribly wrong tonality when listening to HPs :(.

Is it too hard to fit the amp and DAC inside while keeping weight down? Personally, I wouldn't mind a slightly heavier headphone if it means I can have EQ.

You can get some of what you're talking about now with an additional device. The Qudelix-5K is a portable DAC/amp/BlueTooth device that has a 10-band parametric EQ in it with 20 custom save slots (so you can configure up to 20 different PEQs and switch between them). It can be a BlueTooth receiver (including LDAC support) and can run as a USB DAC/amp. The app to configure it runs on a mobile device and communicates with the Qudelix-5K via BlueTooth, and I don't think there is desktop software that can control it when it is running as a USB DAC/amp so you would have to switch your PEQ preset before using it in wired mode if you go that route, but it is otherwise self-contained.

Regarding HRTFs, I think they can work well when your source material is truly multi-channel, and I have yet to experience an HRTF applied to a stereo signal and felt that the result was an overall improvement. For instance, I spent some time comparing Waves NX with head tracking when being fed a 7.1 sound signal from the game Overwatch, which was a pretty good experience, vs. the Dolby Atmos for headphones that is integrated into Overwatch (and able to use the full multi-point with elevation sound data straight from the game engine because it is fully integrated), and the built-in Dolby Atmos is superior and a great experience, even though there is no head tracking. Elevation works and distance estimation based on sound location alone is effective in a way that Waves NX is not. Perhaps Waves NX could be more performant, but there is no way to get elevation data into Waves NX on a PC.

While I haven't tried it yet, I'd guess that David Griesinger's approach to equalize headphones "to achieve truly accurate timbre and frontal localization without head tracking" is probably the way to go for stereo source material (and I'm sure it would help with an HRTF applied to a multichannel source played back on headphones as well). See my post here for more info.

Edit: I forgot to mention there are commercial solutions that offer custom HRTFs for each user based on their ear structure, for instance Embody: "Embody developed a way for users to submit images of their ears to a cloud service, which delivers a generic HRTF that is optimized for each user. Embody uses a machine learning algorithm that models the user's unique hearing anatomy, selecting an adequate HRTF from a single image, captured on a smartphone."
 
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don'ttrustauthority

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Infinitely high pricing in consumer goods is a 21st century thing. There seems to be no limit for audio gear and it's a significant market. Back in the day the no limit price stuff was a tiny slice.
 

jimbomb

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Regarding HRTFs, I think they can work well when your source material is truly multi-channel, and I have yet to experience an HRTF applied to a stereo signal and felt that the result was an overall improvement.

Jumping into this thread just to reiterate an earlier post. If you could hear what I'm hearing with the personalized HRIR (HRTF) produced by Impulcifer I think it would change your opinion. I had tried and been disappointed by numerous off-the-shelf surround devices and SW prior to working with Impulcifer about a year ago, and have been using it exclusively since for all my stereo music listening. Easily the best sound I've ever heard in decades of seeking good sound, mostly with speakers, but with headphones as well. The illusion of spatially realistic live music reproduction it creates is just stunning, and still amazes me. It does take some equipment and effort to do the measurements and get the command line options tweaked just right, but my experience is the potential results are truly next level. It's way beyond worth the investment for anyone motivated and with some DIY inclination. Cheers.
 
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Robbo99999

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Jumping into this thread just to reiterate an earlier post. If you could hear what I'm hearing with the personalized HRIR (HRTF) produced by Impulcifer I think it would change your opinion. I had tried and been disappointed by numerous off-the-shelf surround devices and SW prior to working with Impulcifer about a year ago, and have been using it exclusively since for all my stereo music listening. Easily the best sound I've ever heard in decades of seeking good sound, mostly with speakers, but with headphones as well. The illusion of spatially realistic live music reproduction it creates is just stunning, and still amazes me. It does take some equipment and effort to do the measurements and get the command line options tweaked just right, but my experience is the potential results are truly next level. It's way beyond worth the investment for anyone motivated and with some DIY inclination. Cheers.
I gotta try this sometime!
 

TopQuark

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Now that the 2021 LCD-X review is out, I can't wait to see the LCD-4 and LCD-4z review. Battle of the headphones with the lowest THD?
 

Lunafag

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There's also LCD-R but it's gonna be hard to get one of those since it's a limited launch.
 
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