TRUTHEAR x Crinacle Zero IEM Review

[GaryH]

We need to better model how different deviations form the target are perceived for a smarter updated score model.

The inclusion of the slope variable actually adds some increased sensitivity to lower-Q deviations, just as we'd want psychoacoustically, so it's not as 'dumb' of a model as some naysayers make it out to be.

First the In-ear target needs to be improved.

First you need to present valid evidence it needs improving in the form of controlled blind listening tests.

Find the cause for the mid-elevated result in it's current state, perhaps by using mobile subjects like USound.

I'm not aware of any blind test evidence of listeners finding the Harman in-ear target too 'mid-elevated' (in quiet conditions, which is how the vast majority of audiophiles and reviewers will judge sound quality).

 

[Chromatischism]

Yeah the extra bass would go some way to decrease any perceived shoutiness - this (plus the probable effect of the foam tips) takes the overall spectral tilt to -0.48 (i.e. an overall warm tilt) as Sean calculated, down from 0.31 (bright tilt) calculated by AutoEQ from Crinacle's measurements. So it's effectively a different headphone. And yes it's not easy to see on Sean's graph, but it peaks at ~2 dB above target at 3 and 5 kHz, and that's with the foam tips likely lowering response there. Maiky's graphs show the Truthear's significant deviation from the Harman target the clearest I find:

Yeah. The problem is if we keep raising bass to counter treble and vise versa, we end up with no mids, which is one of my criticisms of the Zero.

 

[markanini]

The inclusion of the slope variable actually adds some increased sensitivity to lower-Q deviations, just as we'd want psychoacoustically, so it's not as 'dumb' of a model as some naysayers make it out to be.

Some isn't always sufficient between 3-7kHz.

First you need to present valid evidence it needs improving in the form of controlled blind listening tests.

I'm not aware of any blind test evidence

I'd go one step further and say we need at least a small study. Some might find compelling the convergence of implied inhouse targets of many IEM brands and USound. The issue is that they are basically closed source. It has been strongly hinted at by someone close to USound that they used mobile subjects whereas its known Harman used stationary subjects. These different usage patterns will cause non-trivial changes to the frequency response.

 

[GaryH]

Some isn't always sufficient between 3-7kHz.

I'd call a 91% correlation between predicted and actual preference ratings petty sufficient.

I'd go one step further and say we need at least a small study. Some might find compelling the convergence of implied inhouse targets of many IEM brands and USound.

Doesn't mean they've done internal controlled blind tests to arrive at that, they're probably just copying (elements of) the USound target (possibly due to its association with a respected figure like Oratory). Many headphone brands used to (misguidedly) follow the diffuse field curve, doesn't mean they were right.

It has been strongly hinted at by someone close to USound that they used mobile subjects whereas its known Harman used stationary subjects. These different usage patterns will cause non-trivial changes to the frequency response.

They tested it in a (stationary) simulated noisy traffic environment. As I said, these are not the kind of conditions in which audiophiles and reviewers judge sound quality.

 

[markanini]

I'd call a 91% correlation between predicted and actual preference ratings petty sufficient.

Yes, that's the beauty of it. When I ranked all headphones I've owned and compared to Harman score it would mostly follow the same order. The outlies had high-Q peaks of 6-9 dB between 5-6KHz in Oratory1990 measurements. Just an aside.

Doesn't mean they've done internal controlled blind tests to arrive at that

Who, Oratory1990? I think he's a pretty data driven guy. But I wont blame him for holding NDAs for his employer.

Many headphone brands used to (misguidedly) follow the diffuse field curve, doesn't mean they were right.

Could you name one?

They tested it in a (stationary) simulated noisy traffic environment. As I said, these are not the kind of conditions in which audiophiles and reviewers judge sound quality.

Good to know, it's been a few year since I read the papers. Do you recall the reasoning for that?

Everyone should agree It's important to control for all significant factors in a highly seal dependent system. I think it's reasonable to expect that the travel of the tips from normal mobile use can have a significant effect on FR. Larger than the effect of outside noise no matter what model. IEMs are (generally) not open backs. Testing mobile subjects can't be such a huge leap. Get me right, I critique because I like Harmans work. I prefer they revise the IE target since they are not bound by NDAs.

 

[GaryH]

Who, Oratory1990?

No, the other brands partially imitating his target.

Could you name one?

AKG.

Good to know, it's been a few year since I read the papers. Do you recall the reasoning for that?

To see if the preferred target changes in a noisy environment. I'm talking about USound here.

I think it's reasonable to expect that the travel of the tips from normal mobile use can have a significant effect on FR.

Don't really know what you're referring to here.

Larger than the effect of outside noise no matter what model.

Big assumption. I don't see any evidence of this.

Get me right, I critique because I like Harmans work. I prefer they revise the IE target since they are not bound by NDAs.

There's no valid evidence it needs revising for non-noisy environments.

 

[Robbo99999]

Oh so do I (in terms of sound at least), I just don't think it's excellent, which concurs with its predicted rating.

I reckon you (and a lot of other IEM first-timers in this thread) might have been less impressed by it if it wasn't your first, as compared to headphones many IEMs generally have smooth responses, good bass extension (due to pressure chamber conditions), low distortion, and good channel matching. It's a shame the Truthear's poor ergonomics have put you off IEMs though, it really is exceptionally bad in that department compared to most others due to the gigantic bore diameter, and there are even IEMs that are designed for shallow insertion e.g. a lot of Sony's, so earwax compaction shouldn't be an issue with them.

Well, I don't really need to use IEM's as I don't consume music in mobile/noisy environments so it's not any real loss....but if I start to want to do that then I'll bear what you said in mind - ie some other IEM's insert more shallow, have better ergonomics, and could be less irritating to the ear. I suppose though, even shallow insertion IEM's are pushing wax at least part of the way back down the ear canal, it's just not pushing it back down as far.

 

[Chromatischism]

I clean my ears, so I don't have issues with that.

 

[markanini]

AKG.

Model name?

No, the other brands partially imitating his target.

And if a wide range of listeners like it better than Harman does that bring us further from a hypothesis worth testing? Lets assume they all ripped off oratory1990, does that change anything?

To see if the preferred target changes in a noisy environment. I'm talking about USound here.

You brought this up so I'm still wondering what would be the explanation? You should know correlation does not equal causation BTW.

Big assumption. I don't see any evidence of this.

Maybe because you assume an IEM stays perfectly still in the ear canal after insertion. In reality it moves a little, once settled it applies lesser pressure which elevates the mid range to the listener. This the something Harman failed to control for by using stationary subjects.
Technically if there is a lack of evidence then that wouldn't necessarily negate a majority of listers disliking what they hear in practice. At some point in time it was false to believe in evolution based on available evidence too.

 

[GaryH]

Model name?

K601.

And if a wide range of listeners like it better than Harman

There's no valid evidence of that in the form of blind listening tests. Many people say they like Grado's in sighted listening, but they did not do well in Harman's blind tests.

Lets assume they all ripped off oratory1990, does that change anything?

No, the other brands partially imitating his target.

You brought this up so I'm still wondering what would be the explanation? You should know correlation does not equal causation BTW.

The only variable changed was external noise, so this determines causation. Whatever the explanation for the change in preference, it isn't 'mobility', because the listeners were stationary in both tests with and without noise.

Maybe because you assume an IEM stays perfectly still in the ear canal after insertion.

And you're making a load of unfounded assumptions. Personally if I make sure to use the correct sized tips for my ear canal and insert the IEM properly, it stays in fine. And if it doesn't I can feel and hear the loss of seal and so bass and push it back in, it's not a subtle effect.

In reality it moves a little, once settled it applies lesser pressure which elevates the mid range to the listener.

Where's your evidence for any of this? Who says the IEM wasn't 'settled' in Harman's tests? If you're talking about a loss of seal, that would likely result in loss of bass as above and so if anything perceived elevated midrange and treble. If you're talking about insertion depth if anything shallower insertion would likely result in lower midrange, not more.

This the something Harman failed to control for by using stationary subjects.

You can't properly control for a variable that may be different for every user and situation anyway, depending on their competence with inserting IEMs and ensuring they stay sealed properly.

 

[GaryH]

Well, I don't really need to use IEM's as I don't consume music in mobile/noisy environments so it's not any real loss....but if I start to want to do that then I'll bear what you said in mind - ie some other IEM's insert more shallow, have better ergonomics, and could be less irritating to the ear. I suppose though, even shallow insertion IEM's are pushing wax at least part of the way back down the ear canal, it's just not pushing it back down as far.

I really don't think it's something you need to worry about, unless you're regularly using triple-flange Etymotics (which I wouldn't recommend for multiple other reasons anyway!). Occasional to moderate usage of a shallow (or even medium) insertion IEM is unlikely to result in wax compaction. Other than mobility and isolation IEMs do have some sonic advantages over headphones as I mentioned before, especially the infinitely extended sub-bass you can get with some fully closed front volume models (not the Truthear) due to IEMs more easily creating a complete seal than headphones and so operating in full pressure-chamber conditions in the bass, as well as the more 'intimate' sound of IEMs which can make it seem like you're 'inside' the music and works particularly well for some vocals.

 

[markanini]

K601.

It looks like we found one! It's still a rare tuning so if this is you evidence of manufacturers blindly copying targets it's a weak one.

The only variable changed was external noise, so this determines causation. Whatever the explanation for the change in preference, it isn't 'mobility', because the listeners were stationary in both tests with and without noise.

I'm asking you for the third time to provide a source. If you can't how do I know this is true?

And you're making a load of unfounded assumptions. Personally if I make sure to use the correct sized tips for my ear canal and insert the IEM properly, it stays in fine. And if it doesn't I can feel and hear the loss of seal and so bass and push it back in, it's not a subtle effect.

I don't need to add expletives but, as I thought, you are making an assumption. Naive users will insert IEMs excessively deep. This will happen no less to the participants of Harmans study when prompted to check their seal. At the same time I've confirmed with an audiologist and an ENT that there are forces in ear canal that work to push foreign object in an outward direction. A well fitting tip will prevent lost off seal at the end if the travel. As far as Harmans study goes this will produce erroneous data to the outcome. You would have to argue that the target should represent people that incorrectly insert their IEMs. In that case you would have to justify why it wouldn't be biased to exclude participant with broken seal, yet excessively deep insertion is OK.

If you're talking about a loss of seal

I don't think I can claim that loss of seal is the only cause, if at all. I will point to Etymotic products which are designed for deep insertion. They measure with a very mid forward response but listeners report correct sound. Reverse conditions dictate a shallow-insertion design would have reduced mids when inserted deeply. Both designs assume good seal BTW.

You can't properly control for a variable that may be different for every user and situation anyway, depending on their competence with inserting IEMs and ensuring they stay sealed properly.

That's why I would suggest a simple control like an activity to encourage the IEM to settle. This way they may also keep being inclusive and having a mix of trained and untrained participants.

 

[GaryH]

I'm asking you for the third time to provide a source. If you can't how do I know this is true?

Here you go. That's the first time you've asked for a source.

Naive users will insert IEMs excessively deep.

Unfounded assumption #1 (of this post).

This will happen no less to the participants of Harmans study when prompted to check their seal.

Unfounded assumption #2.

A well fitting tip will prevent lost off seal at the end if the travel. As far as Harmans study goes this will produce erroneous data to the outcome. You would have to argue that the target should represent people that incorrectly insert their IEMs. In that case you would have to justify why it wouldn't be biased to exclude participant with broken seal, yet excessively deep insertion is OK.

Unfounded assumptions #3-6? I'm losing count.

I will point to Etymotic products which are designed for deep insertion. They measure with a very mid forward response but listeners report correct sound.

Maybe anecdotal sighted listening. Not in Harman's blind tests. I suggest looking again at this post (which you 'liked' at the time).

Reverse conditions dictate a shallow-insertion design would have reduced mids when inserted deeply.

Fallacious reasoning, and contradicted by the measurement data I linked previously.

That's why I would suggest a simple control like an activity to encourage the IEM to settle.

This will likely introduce random differences across different people and even repeated tests with the same person. That's not how you control for a variable.

 

[markanini]

Unfounded assumption

The issue with that response is taking statements in papers as axioms. There's not enough resources to put every single fact related to audio tech into papers. We are past some issues which you want to think are are undisputed for some reason. We have the work of Gaëtan Lorho and oratory1990 which shows different outcomes than Harman IE. The later has no published papers though so you are not holding yourself to the same standard by accepting his statements on face value. It would be childish for me to count the number of unfounded statements you have made, but either way I don't value factual statements merely by their existence in a paper, of being stated by a random person of authority. I don't see the reason for anyone to subdue their capacity or causal thinking in that way, unless they were in the process of putting together a paper for submission to a journal. In that case what are you doing arguing on an internet forum, procrastinating? Do you think future papers will include reddit posts as references?

 

[isostasy]

I'm asking you for the third time to provide a source. If you can't how do I know this is true?

'Additional research performed by USound and IEM showed that in the presence of background noise (such as distant traffic), listeners tend to prefer more bass and slightly less treble compared to the original Harman Target.

For this reason, USound’s USOUND1V1 reference target was tuned by expert listeners to contain more bass energy below 300 Hz, at the same time exhibiting a more smooth and timbrally accurate reproduction of the upper midrange and treble response. This results in a warm and punchy sound without sacrificing clarity, which maintains the original timbre of voices.'

from Usound. Not sure why Gary didn't link this because I'm pretty sure this is what oratory1990 is referring to in the reddit post.


Remind me what you both are actually arguing over again?

 

[Chromatischism]

Additional research performed by USound and IEM showed that in the presence of background noise (such as distant traffic), listeners tend to prefer more bass and slightly less treble compared to the original Harman Target.

I experienced this on a trip recently. On the plane, the bass seems really weak. The effect is also noticable in any other noisy area but to a lesser degree (nothing compares with the roar of the plane). I found that when I was testing the Zero and fixing the response, I had to be in a mostly quiet area. And yes, that is with seal.

 

[GaryH]

Not sure why Gary didn't link this because I'm pretty sure this is what oratory1990 is referring to in the reddit post.

Because I saw he already commented on the very thread in which that was initially posted on here, so I assumed he was asking for a source that the subjects were stationary, which I provided.

 

[markanini]

Remind me what you both are actually arguing over again?

+1 Based on his post history we have similar tastes in IEMs with less mids than Harman IE. https://www.audiosciencereview.com/...e-zero-iem-review.37380/page-103#post-1379185

 

[GaryH]

Nope. No idea how you came to that conclusion from that post.

 

[markanini]

I experienced this on a trip recently. On the plane, the bass seems really weak. The effect is also noticable in any other noisy area but to a lesser degree (nothing compares with the roar of the plane). I found that when I was testing the Zero and fixing the response, I had to be in a mostly quiet area. And yes, that is with seal.

It's unknow what kind of noise was used. Plane noise is something like broadband brown noise. Cabin pressurization might vary causing different perceived response for reasons other than seal alone.

Oratory1900 has shared a lot of great knowledge which can be generally trusted. At the same time statements related to work done on behalf of his employer might be subject to coded language or not disclose a full context to comply with possible NDAs. The name USound is also the name of the company he works for: https://usound.com/

Sean Olive mentioned the work of Gaëtan Lorho on his Twitter. I haven haven't gotten hold of Lorho's paper yet, but the outcome looks like less mids vs Harman-IE, which is also what USound came to.

https://twitter.com/i/web/status/1597663475199004672