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ZMF Caldera Headphone Review

Rate this headphone:

  • 1. Poor (headless panther)

    Votes: 48 27.0%
  • 2. Not terrible (postman panther)

    Votes: 84 47.2%
  • 3. Fine (happy panther)

    Votes: 29 16.3%
  • 4. Great (golfing panther)

    Votes: 17 9.6%

  • Total voters
    178

fredristair

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This thread is honestly ridiculous from every side you can view it - Jesus. Thank god I’m over my headphone and speaker search and not brand new to this hobby.

I agree. Aside from Amir's original review which is always intersting there is nothing to read but maybe Solderdude's posts, which also can be excellent. Little has been learned about the Caldera in this thread aside from that.
 

fredristair

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I mentioned way earlier in the thread that some clueless people refer to Harman as Harmon lol. Glad to see it hasn't stopped. But @fredristair is definitely here in bad faith. I'd ignore him if I were you.
Not really. I just can't seem to get somebody to tell me why you can't have a headphone on the level of a Susvara tuned exactly to Harmon with all that bass. I wouldn't build a 10-15000 system around Dan Clark stuff.
 

DenverW

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I didn't change what I said. Headphones are for reproducing a signal. Music is one such signal, and what most of us are primarily concerned with here. So no, it's not "quite different in itself", I said the same thing using different words, which I hope you'll permit me to do? If you can't get on board with basic definitions like what an audio signal is then this is my final attempt to engage with you. This isn't a matter of opinion.

Show me the last time a gaming, aviation, or office headphone was reviewed here.

I'm sorry my made up example upset you as I missed your earlier post so could only guess why you were disagreeing with my statement that headphones are for reproducing a signal. I'm sorry if I come across as blunt and I'm not trying to condescend to you about your preferences. You registered literally this week and very quickly ended up agreeing profusely with an analogy which seemed to confirm your feelings. Moreover, you began with "I know some people are having trouble with the analogy" as if we simply didn't understand it. I tried to explain how, on the contrary, the analogy just doesn't work, regardless of whether it seems to support your viewpoint (it's a fallacy, see above). You then admitted that it doesn't even matter to you how much I demonstrate the inadequacy of the analogy, not only will it not change your opinion, it will reinforce it.

So no, it's not a scientific paper, but this is Audio Science Review and if 'sound' is really most important to you then I feel you could get more out of this forum than agreeing with the first analogy that reinforces your preconceived opinion.

I like this post by @_thelaughingman : "Engage in a topic from the perspective of wanting to learn something new about the hobby of being an audiophile.". If you've joined and immediately found an analogy that supports what you already think, then in the face of being told the analogy itself is flawed, respond that you don't care, that suggests to me you haven't learnt anything.

I'm honestly trying to engage you in the spirit of this forum which I believe to be critical thinking and objective analysis and, as petty as disagreeing with an analogy seems to be, I believed pointing out a false analogy based on flawed logic was a good way to do that and easier than getting into fine details to do with frequency responses, statistical analysis, etc. I'm sorry if this came across as blunt and I'm certainly not trying to tell you what you think.
So hey, don't engage sounds perfect. Any semblance of an apology in there was overruled by doubling down on how right you are, and how justified everything you said was because of the 'spirit of the forum' while just doing the same things in a longer post.

And just to reinforce the idea of being humble to ideas in your posts: https://www.audiosciencereview.com/...ds/audeze-mobius-review-gaming-headset.26375/
 
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amirm

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It always seemed to me that you couldn't really tune a headphone to Harmon without compromising the sound quality - Sennheiser would've done it by now and which is why the HD650 (or 600) remain so near-perfect to this day and they haven't been able to top it. A lot of people like the Stealth here but it doesn't get much praise in comparison to many other TOTL headphones. It seems like you are losing out on a lot of technicalities and why headphones (making them really amazing) are really hard to tune to Harmon - see Susvara or Utopia.
We don't go by what "seems" to be the case by someone. I have EQed probably 100 headphones and in every case the improvement is dramatic, and superbly performant. In many cases not only do you get the full response back but also add spatial qualities which you had lost.

Manufactures don't implement Harman curve because they don't want to. Many are sticking to their own ideas without being able to back the efficacy of that. Otherwise why not put out a report proving what you say? That an EQed headphone sounded worse?

There are some headphones whose drivers have excursion issues in which case you can get closer to Harman but not fully there. That is no excuse to not even try.

In the case of the Caldera I have EQed in bass and had wonderful results. Owner got his back and had the same outcome.

As to Stealth not getting as much praise, you have no way to quantify that. As I noted earlier, I asked Dan Clark what the reaction has been and he said it has been a great success. We have the best proof of that by them releasing a third headphone with such tuning.

Ultimately though, this market is dominated by marketing first, performance second. Same with speakers. People buy with their eyes, not ears. So technical excellence only goes so far. Hopefully companies who do have great marketing, also add great technical abilities to their headphones and our selection become larger.

Finally, there are a number of people including reviewers who have been on record in saying they don't like Harman response. For them to say that Stealth sounds good is not something they can do without losing face. You may have noticed some that continue to misspell Harman. So don't look for truth telling there.
 

DenverW

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This is just massively cheesy trolling for someone to continue to do that. No likely earning themselves brownie points or merit badges in some other forum.
I took it to be making a point through trolling as well. Did you see something in another forum or is the 2nd part conjecture?
 

solderdude

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Shure made a 10/10 closed passive over-ear headphone for $60 back in 2009:
Yep, that's what the number says.

It has a +5dB treble peak (which makes it sound sharp), it is rolled off in the bass (unlike a Harman tuned headphone).
Also clearly visible in Oratory measurements.
It suffers from compression in the 100Hz region above 80dB SPL thus has high 3rd harmonic distortion.
It is quite seal dependent (being closed so not surprising)
The headband falls apart and gets ugly.
The headband creeks.
The pads are uncomfortable, are 'sweaty' and start to crack after some heavy usage.
Impulse response:
sqr-srh-440.png


below the 'lower ranked' HD650 needle pulse
K240 100us.png



That's what one buys when trusting such numbers....I am sure the numbers don't lie but this is not really a high fidelity headphone but rather a cheap monitor headphone for studio usage.
Yes... I owned one.
It isn't particularly bad but the sound is not what I would call 'Harman target', far too bass-light and sharp sounding to be 'preferred' but nice as a studio monitor for shure.

Slap some SRH940 or SRH1540 pads on it, put some toilet paper in front of the driver and it improves a lot in comfort and sound quality.

My personal opinion on the sound:
The sound is ‘warmish neutral’ with sharp treble up top. This is good for monitoring because you can pick out details more easily. For music enjoyment the treble is a tad too sharp at times. Bass doesn’t go deep but sounds full and accurate.
Mids have a warmish neutral character. The sound is dynamic. Treble is not ‘refined’. Bass quality is better than the SRH840 which is a bit bassier but also muddier/less well defined.
 
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amirm

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Yep, that's what the number says.
Yeh, as with speakers, bass response is not properly incorporated in the model:

"The mean error is based on the sum of the
absolute values for each y-value in the headphone
error curve from 50 Hz to 10 kHz divided by the
total number of n values as defined in equation 1: "

Personally I would go from 20 Hz to 8 kHz. Beyond 8 kHz, measurements are not reliable anyway. For my own EQ, I often stop below 8 kHz.

Response of this headphone definitely drops below 50 Hz:

1702768747122.png


Related to this, Harman didn't use any music tracks with sub-bass content.
 

raif71

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You are close. If we were to pick a flavor of ice cream that most people would like, wouldn't chocolate be the one instead of a random one? Pretty sure Dorian Fruit flavored ice cream wouldn't make it.....
Since people are making a fuss about Harmon (rightly so), then I'm picking the "dorian"

1702768923734.png


It should be "durian", ya :)

Of course, I'm assuming you're actually referring to the fruit...There is also the Dorian Gray character ...
 

solderdude

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I would have thought the AKG K371 was very close to Harman also

Well it kind of does in the sense that it has elevated lows (but a tad too elevated) and has a dip at 4kHz and a too low response there.
I had great difficulties keeping a good seal when walking around with it making the bass jump from left to right and up and down in level.
index.php


Compare that to this:
index.php


Even the active Harman headphone below does not follow the target that exact.
index.php


This is what I mean with 'follows' the Harman curve, rather than the silly number game and excluding the typical bass boost of the Harman target.
Of course, all measured on a specific fixture under near ideal conditions.
 
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amirm

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Since people are making a fuss about Harmon (rightly so), then I'm picking the "dorian"
No need. It is a borrowed word so either spelling is fine. From the Wiki: Other historical variants include duryoen, duroyen, durean, and dorian.[6]
 

isostasy

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So hey, don't engage sounds perfect. Any semblance of an apology in there was overruled by doubling down on how right you are, and how justified everything you said was because of the 'spirit of the forum' while just doing the same things in a longer post.

And just to reinforce the idea of being humble to ideas in your posts: https://www.audiosciencereview.com/...ds/audeze-mobius-review-gaming-headset.26375/

I can be genuinely apologetic for missing your previous post and for writing my previous posts too bluntly, whilst also maintaining that I am correct r.e. my other point. This point simply being that our discussions on Audio Science Review about headphones primarily considers them in the context of listening to music, which can be described as a signal. I'm frankly baffled why you've taken this up as a point of contention in the middle of this thread as it precludes all discussion of the merits of the headhpone in review.

On which note, this was supposed to be relevant to the discussion of why the ZMF Caldera reviewed here isn't regarded that well, because it falls short of the benchmark by which that reproduced signal is assessed.

I'm not sure what you mean by "doing the same things". As I said, I was trying to explain how the analogy previously used didn't work and what I believe most of us here accept as the purpose of a headphone on this forum: to reproduce a signal, specifically recorded music. I'm still sorry for any blunt language I used.

Thank you, you've perfectly illustrated what I was attempting to inform you: I'm surprised you did exactly as I asked and found a review of a single gaming headset from over 2 years ago amongst an ocean of headphones manufactured for the purposes of listening to music. And does Amir assess it using any different measure than any other headphone review, i.e. based on the faithfulness of the signal it reproduces? No.

I found you the only other gaming headset review I could find to save you the bother in case you were saving it for another rebuttal.

Headphones are designed to reproduce a signal, most notably recorded musical content. This shouldn't be controversial.
 

isostasy

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This is just massively cheesy trolling for someone to continue to do that. No likely earning themselves brownie points or merit badges in some other forum.
It's unfortunately difficult to differentiate genuine beginner misunderstanding and questioning and trolling sometimes though. Some of us (definitely include myself as can be seen) are easily triggered when we assume the best, that someone simply misunderstands, only to come up against something different.

And being an English language forum can be difficult for some people which doesn't reflect on their audio knowledge or capability for understanding so I don't like to assume anything from seemingly badly written posts. So again, an easy way to trap us.

Repeatedly spelling Harman wrong whilst the rest of the posts are word perfect and after having been corrected multiple times is suspect though, I agree.
 

zach915m

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In an effort to try to keep as much peace as possible, and subject myself to more of this fun, I have a BOKEH that I set aside for Amir this week and put it in Harman format (no front mesh, hybrid Bokeh pads) and will send it to Amir on monday. Yes like any headphone there are deviations, and the pads have to be angled correctly to get the right ear gain on the coupler, but in that format it's closer to Harman than many of our other headphones. @amirm I will send you a PM to get your address. Thank you.
 

fredristair

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We don't go by what "seems" to be the case by someone. I have EQed probably 100 headphones and in every case the improvement is dramatic, and superbly performant. In many cases not only do you get the full response back but also add spatial qualities which you had lost.

Manufactures don't implement Harman curve because they don't want to. Many are sticking to their own ideas without being able to back the efficacy of that. Otherwise why not put out a report proving what you say? That an EQed headphone sounded worse?

There are some headphones whose drivers have excursion issues in which case you can get closer to Harman but not fully there. That is no excuse to not even try.

In the case of the Caldera I have EQed in bass and had wonderful results. Owner got his back and had the same outcome.

As to Stealth not getting as much praise, you have no way to quantify that. As I noted earlier, I asked Dan Clark what the reaction has been and he said it has been a great success. We have the best proof of that by them releasing a third headphone with such tuning.

Ultimately though, this market is dominated by marketing first, performance second. Same with speakers. People buy with their eyes, not ears. So technical excellence only goes so far. Hopefully companies who do have great marketing, also add great technical abilities to their headphones and our selection become larger.

Finally, there are a number of people including reviewers who have been on record in saying they don't like Harman response. For them to say that Stealth sounds good is not something they can do without losing face. You may have noticed some that continue to misspell Harman. So don't look for truth telling there.
Respectfully EQ all you like (not for me). But I disagree that the lack of headphones out of the box to match that preference is because the designers 'didn't want to'. Just seems like a real technical limitation there where you are robbing Peter to pay Paul and there is no great headphone that has what you are asking (yet).
 
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Chagall

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Respectfully EQ all you like (not for me). But I disagree that the lack of headphones out of the box to match that preference is because the designers 'didn't want to'. Just seems like a real technical limitation there where you are robbing Peter to pay Paul and there is no great headphone that has what you are asking (yet).

So your theory is that Harman-matching headphones must be difficult to make because none of them sound great - aren't great headphones. The only reason you give is because some reviewers you follow didn't like Stealth. OK...

Susvara has the typical Hifiman 1-3k dip and lacks low end. I would certainly fill in that low end and I'm sure it would sound lovely and much better than out-of-the-box.

Screenshot_4.png
 

fredristair

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So your theory is that Harman-matching headphones must be difficult to make because none of them sound great - aren't great headphones. The only reason you give is because some reviewers you follow didn't like Stealth. OK...

Susvara has the typical Hifiman 1-3k dip and lacks low end. I would certainly fill in that low end and I'm sure it would sound lovely and much better than out-of-the-box.

View attachment 334931

So my theory is that headphones matching that target must be difficult because not one open back headphone matches the target - and those that might be close are not truly worth investing in and building a setup around - basically you name it on all the TOTL headphones from headphone history. It's a simple point. Of course you can EQ a headphone, thanks for reminding me. It's maybe a dumb point but important in a thread demanding headphones to match that target.
 
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