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ZMF Caldera Headphone Review

Rate this headphone:

  • 1. Poor (headless panther)

    Votes: 47 25.7%
  • 2. Not terrible (postman panther)

    Votes: 85 46.4%
  • 3. Fine (happy panther)

    Votes: 31 16.9%
  • 4. Great (golfing panther)

    Votes: 20 10.9%

  • Total voters
    183
Yep, I admit I expected a bit more from Zach.
Looks like an attempt for damage control but alas that back-fired. A bit more restraint, kindly worded arguments and discussion would have saved a lot.

Too bad... design and looks are great.
I agree with this. Especially as I'm also not completely convinced about the harman curve. I understand this argument about the necessity of standards. And I understand the problem with the circle of confusion, but at the same time it is very individual how our hearing perceives the reproduction of sound in a pair of headphones. I'm not so sure this can be standardized. Just the fact that hearing deteriorates with increasing age means that one's preferences can change over time. It's just an example. There are several other examples that illustrate this with individual preferences. I think some form of EQ will always be needed, and I wonder if not just how well a headphone responds to eq is one of its most important qualities. Then you can think what you want about @amirm's arguments and opinions, but that people are afraid to say what they think, or that people would be silenced, I have not perceived that at all. It's just a ridiculous argument as I see it.
 
I have the ZMF Auteur which I love for simple acoustic music, but I find it falls apart with more intense, busy stuff. As Amir proved with his subjective listening comments on the E3 vs the Stealth, sometimes less accurate is more pleasing to the ear.
 
You are misapplying that experience. A doctor with 10 years of experience does have more intuition and wisdom than another doctor who doesn't. But here, we are talking about two disciplines: building headphones and creating a target frequency response. I have no doubt Zack has gained that knowledge and wisdom in building headphones. Given its great looks, and good work in marketing, he clearly has validation of that. He has however done no formal studies of any kind in listener preference. So cannot present any wisdom or intuition.

This statement would be true if the maker spent the past 12 years only with woodworking perfecting his craftsmanship creating nice looking earcups. Which as you know is simply not true. The maker is using measuring equipment and is finetuning the frequency response and many other aspects of sonic reproduction of his designs. For years. I highly doubt that the he isn’t aware or interested in listeners preference. It was stated in this thread several times that Harman target is something that is one of the steps during the design process. You ignore all of that. You are trying to sound objective, but your selective use of facts to strengthen your point make you sound rather biased. Its not a way a dialogue can emerge and I am not surprised that this is going nowwhere, while it could be a very interesting discussion, between a reviewer and a maker both having a lot of experience but coming from very different directions in regard of audio reproduction.

Your comments about this and that owner liking a headphone has no value. We review because we want to get to facts, not personal opinions biased by many factors outside of performance. The headphone market is heavily polluted by youtubers who will praise anything expensive loaned to them for testing. And if it is expensive in their book, it must be great. Even when they measure, they paper over the facts that conflict with their subjective remarks. This is why I started to test headphones.

You yourself are validating your “scientific approach” with “what most people like” Its obvious that ZMF is very successful and a lot of people from the audiophile scene do like the tuning. ZMF was NOT always well received by the youtube reviewer crowd, designs like Verite Open became mixed reviews and big youtubers like ConvinceMeAudio seem to prefer older designs to recent releases like Caldera. Others see Caldera underpriced considering its perfomance compared to stuff like Abyss or Susvara. You are painting a picture of corporate influencer marketing for simpletrons that is simply not there. Again, to strengthen your point.

Maybe there is some common ground of what “most people” like but I don’t think you can make a finite statement like “it is definitely what most people like” alone because of the sheer amount of different audio gear, different approaches that lots of people highly appreciate. Apart of that I believe that mainstream consumer and hi-fi market are very different groups of people with different preferences. And I am yet to find a that mythical 250 usd headphone that is loved by the mainstream market, which performs to a level of a high end design that is tuned to my personal preference. Personally I buy ZMF primaly because of the tuning NOT because of the craftsmanship and the luxury aspect, which sure are a nice cherry on top.

Apart of all of this noone in this thread could answer how you measure the size of the stage, the natural body and decay of the instruments, the texture of the bass and the illusion of holography. How do you messure the harmonics and resulting quality of timbre which, at least, for me, is the most important foundation of sound (paraphrasing a statement of another audiophile here). Harman target is still very important, just over-relied by on and overstated as a primary reliable data point to heavily weigh decisions upon by some.

Harman research is one of the steps in understanding audio and understanding what we like and what not, but its no singular holy book that is to be blindly followed, there much more research and empirical trial and error to be done before we arrive at something that we can call a universal music reproduction standard.

There is another major reason why what he is doing is wrong: it continues to randomize the music industry. We all need to get behind one standard that is used both in production and playback. Only then we have any hope of hearing what the artist approved (and heard). If we continue this wild west of every designer's idea being right, we will never get there. With a single standard that is close to what many like, we have a headphone that can be used without EQ. And those that don't agree, can EQ to what they like.

That’s a question of your approach and of your ethos, but no absolute truth with a right and wrong. Many people on this board will agree with you since the idea of creating one singular standard is nothing bad per se and might help many of us, especially new people in the hobby with finding some orientation.

Other may argue that you are asking the artists to use a limited set of colours without deviating from it since they might randomize the art industry making it difficult to find objective truth. Other may argue that they don’t want all audio reproduction to sound mostly the same tuned to one target curve. I understand your reviewer perspective and how you come to this conclusion, its still just an idea which to be honest I doubt will ever come to fruition. Another thing are the recording studios and artists that would have to record according to a certain standard, which just aint happening, we are still talking about art and not about accounting.

I am still very curious what pads, what chain and which reference tracks you used for your review Amir.

Well usually to me trying first, reading reviews later is the best approach. Try Caldera yourself at a fair or your audio dealer, compare yourself the EQ that Amir proposed with the tuning that the maker came up with, the EQ is eaisly implemented in roon. I think for the most the conclusion will be obvious since comparing the EQ with the stock tuning alone is making it glaringly obvious that there is more to audio reproduction than applying the harman curve.

Open mindless is important especially if you are claim to follow a scientific approach. I don’t think Zach tried to convey anything else in this thread.
 
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Open mindless is important especially if you are claim to follow a scientific approach. I don’t think Zach tried to convey anything else in this thread.
I do apologize if something I said in this thread offended anyone, my only point was to speak as a designer of headphones against the idea that listeners need to make sure they adhere to a single target as enjoyment, not that that target doesn't have validity.

I've done a lot of work via the CAMS magnet system, Asymmetrical Caldera pads, and Atrium Damping system (which is now fully patented) to make sure my work on acoustics is not in vein. While the validity absolutely should be questioned the tests to me, those I work with and many owners hold some sort of merit and do explain why people may like zmfs that don't adhere to Harman. And sure, more research is needed, I look forward to it.

I use the Harman target every time I design a headphone and we do have designs that are closer to it like the Atrium Closed and Bokeh in certain pad and mesh combinations, but not because I as the designer feel that's the only adherence there can be.

I spend a lot of time at a headphone booth watching audiophiles talk about their differing views with the same experience. Audiophiles just are a different crowd than the general population of which Harman speaks for, and as @solderdude pointed out there is nothing more personal than a headphone for many of us.

@amirm i appreciate that I am not being moderated. All I had to go on was that my posts stated they were being held for review, then when I came back an hour later there were numerous posts by you. My apologies.
 
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I will check this out but I meant more so are the actual experiments with the experimental data published anywhere. the way we would for other research. These are more like review papers summarizing work.

It's hard to really understand what the research really says and how it applies without knowing the details of experimental design, sample size and selection bias if any, etc etc.

Edit:
This is not meant to be a criticism or a decision to ignore research which I think is the best way to make progress in any field. It's just hard for me to believe and engage in it in a meaningful way esp the discussions without seeing the source data.
 
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I will check this out but I meant more so are the actual experiments with the experimental data published anywhere. the way we would for other research. These are more like review papers summarizing work.

It's hard to really understand what the research really says and how it applies without knowing the details of experimental design, sample size and selection bias if any, etc etc.

Edit:
This is not meant to be a criticism or a decision to ignore research which I think is the best way to make progress in any field. It's just hard for me to believe and engage in it in a meaningful way esp the discussions without seeing the source data.

I'm afraid you'll have to read the actual articles for that I think ;) .
 
I'm afraid you'll have to read the actual articles for that I think ;) .
Yeah honestly I'd love to! I was trying to find them through pubmed but they aren't available there. Which makes sense because they aren't medical research.
 
I will check this out but I meant more so are the actual experiments with the experimental data published anywhere. the way we would for other research. These are more like review papers summarizing work.

It's hard to really understand what the research really says and how it applies without knowing the details of experimental design, sample size and selection bias if any, etc etc.

Edit:
This is not meant to be a criticism or a decision to ignore research which I think is the best way to make progress in any field. It's just hard for me to believe and engage in it in a meaningful way esp the discussions without seeing the source data.
You will have to dig through the list of papers in the references of the Acoustics Today article. Also, below are 2 slides from the presentation in the second link from my post.
Papers.png
 
ZMF was NOT always well received by the youtube reviewer crowd, designs like Verite Open became mixed reviews and big youtubers like ConvinceMeAudio seem to prefer older designs to recent releases like Caldera.
"big youtubers", haha that is really funny. Probably even with a degree from the YouTube university, I guess. By the way, this guy has a meager 5 mil followers and is one of the worst subjectivists around.

Others see Caldera underpriced considering its perfomance compared to stuff like Abyss or Susvara.
Not stopping to be funny. Yes really, it should cost much more to enter "real" audiophool territory.
Personally I buy ZMF primaly because of the tuning NOT because of the craftsmanship and the luxury aspect, which sure are a nice cherry on top.
You could find such a weird tuning easily in a $100 headphone.
 
"big youtubers", haha that is really funny. Probably even with a degree from the YouTube university, I guess. By the way, this guy has a meager 5 mil followers and is one of the worst subjectivists around.


Not stopping to be funny. Yes really, it should cost much more to enter "real" audiophool territory.

You could find such a weird tuning easily in a $100 headphone.

Which headphones have the same tuning or did you mean are equally off target in a different way
 
I'm pretty sure there's many of you on this forum who enjoy a headphone that isn't tuned exactly to @amirm 's cult of Harman tuning, but are afraid to speak up because of the insane groupthink that happens here.
Ha! You clearly do not frequent these forums.

Others see Caldera underpriced considering its perfomance compared to stuff like Abyss or Susvara.
How the hell Abyss and Susvara ended up in the same bucket?
 
How the hell Abyss and Susvara ended up in the same bucket?
Susvara and Abyss TC 1266 are widely considered high performers in their areas among audiophiles who are actually spending on hi-fi gear in the hobby, both sit in a similar price bracket. Both are very different though. To some extend I found that Caldera to be somewhere in the middle presentation wise, offering effortless layering and excellent detail, that reminded me of Susvara but it presents the recordings with a lot of weight to the notes wich reminded me of TC 1266 that I owned.
 
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Susvara and Abyss TC 1266 are widely considered high performers in their areas among audiophiles who are spending on expensive gear in the hobby, both sit in a similar price bracket. Both are very different though.
I don't think a lot of people who participate in this forums care what audiophiles consider. If you would like to convince more people here, I would recommend backing your claims with more than considerations of audiophiles and random YouTubers.
 
I don't think a lot of people who participate in this forums care what audiophiles consider. If you would like to convince more people here, I would recommend backing your claims with more than considerations of audiophiles and random YouTubers.
Its impossible to give an accurate impression of audio reproduction by a harman target graph alone, for reasons I stated above, which you are free to debunk.
Thats why I would always advice to hear the gear for yourself, and use messurements as somethign that gives you an answer why some thigns work the way they do. Hearing gear for yourself is very much possible nowdays, should there be a genuin interest in audio. Or find someone or a group of people with integrety and similar taste as yours when it comes to advice and an actual purchase. Some yotube reviewers are doing great job at this and I dont think its wise to generalize like you did. Apart of that I believe to see far more influencers in mainstream audio segment than in the audiophile segment, for economical reasons alone.
Ranting about expensive gear starring at one-dimensional graphs, is not really my hobby, I am more into enjoying music and into design and science behind the gear I find intereseting. And I highly enjoy a good discussion on that topics.
 
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Its impossible to give an accurate impression of audio reproduction by a harman target graph alone, for reasons I stated above, which you are free to debunk.
Thats why I would always advice to hear the gear for yourself, and use messurements as somethign that gives you an answer why some thigns work the way they do. Hearing gear for yourself is very much possible nowdays, should there be a genuin interest in audio. Or find someone with integrety and similar taste as yours when it comes to advice and an actual purchase. Some yotube reviewers are doing great job at this and I dont think its wise to generalize like you did. Apart of that I believe to see far more influencers in mainstream audio segment than in the audiophile segment, for economical reasons alone.
Ranting about expensive gear starring at one-dimensional graphs, is not really my hobby, I am more into enjoying music and into design and science behind the gear I find intereseting. And I highly enjoy a good discussion on that topics.
I don't disagree with what you are saying, assuming you mean Frequency Response graph instead of Harman target graph. I agree, a lot of people overestimate how much information we can currently extract reliably from FR graphs. But that does not mean FR graphs and other measurements do not tell us anything. Take the case of Abyss for example. It has an inexplicable tuning, have horrible resonances and distorts badly at high levels. So listen away as much as you like - that is one crappy headphone regardless of what people who call themselves audiophiles consider.

For Caldera, I don't think that is the case. I don't think Caldera is an objectively bad headphone, and original review from Amir says as much as well. It has good, low distortion that would allow you to tune it to your liking, and its original tuning is not great but is not horrible either. So there is that.

I think it is bad idea and advice to recommend to find someone with integrity and similar taste to follow for your purchases. That is "bro science" and never served any community well. You might not agree with Amir's conclusions but his data is reliable. My recommendation would be to find a device that looks like it would have a good tuning and low distortion based on measurements and go try it yourself if you can to see if you like it.
 
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But that does not mean FR graphs and other measurements do not tell us anything.
Never said that, I find graphs important. TC 1266 wasnt to my liking either, and yep distortion is one of the reasons.
its original tuning is not great but is not horrible either.
Did you hear the Caldera or is your statement based Amirs review?

I think it is bad idea and advice to recommend to find someone with integrity and similar taste to follow for your purchases.
It comes down to integrity. I dont see an issue if the person in question, shares your preferences in music, audio reproduction and doesnt usually fall for a hype.

You might not agree with Amir's conclusions but his data is reliable
I never argued that its not, I am looking at Amirs graphs for years at this point and often his messurement work was absolutely in line with my own impression. He is doing great in that regard.

This review is off from my humble opinion, as far as I can judge not the messurements. What I find really interesting about this review is how adamantly he claims to have come up with better tuning than the designer and how lacking his EQ is to my ear, while I really do enjoy the stock tuning.
 
He is obviously trolling and I wonder why this rudeness is tolerated.
The troll is you. By the way, did you realize that you have not received a single like on any of your badly informed comments? Think about it.
 
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