This is a review, listening tests, equalization and detailed measurements of the ZMF Caldera planar magnetic headphone. It is on kind loan from a member and costs US $3,500.
The Caldera is absolutely gorgeous to look at. It is lightweight and with its large cup, very comfortable to wear.Will have to find out from the owner which set of pads it came with.
EDIT: owner let me know that it has stock lambskin perforated pads.
The large cups allowed almost instant fit on my GRAS 45CA headphone measurement rig. I am always happy when that happens.
ZMF Caldera Headphone Measurement
As usual we start with the headphone frequency response measurement and comparison with our target:
OK, I get the flattish bass response but what is up with the three troughs above 1 kHz? Watching company video, they talk about their house sound but one has to be quite daring to choose a response like this. Fortunately the big areas should be relatively easy to fill in with EQ:
The large drivers produce very little distortion even at highly elevated levels:
There are some narrow band errors though which would have bee nice to iron out:
I forgot to mention the messiness above 10 kHz which we also see in Group Delay:
As expected from planar magnetic drivers, impedance is essentially flat:
Combine that with average sensitivity and you have a headphone that is pretty easy to drive compared to a lot of its competition:
ZMF Caldera Listening Tests and Equalization
First impression out of the box was inoffensive but pretty boring sound. There was almost no deep/sub-bass response so that was the first low hanging fruit to fix with equalization:
That alone made a remarkable difference. But the job needed to be completed with the three other filters to fill those holes. Once there, I liked the effect very much but thought the sound was a big bright so took down the peaks a bit. With the complete package, the transformation was dramatic as you can imagine. There was impressive bass and excellent detail and quite good spatial effects.
This testing was more exacting than usual in that I had listened to the same test tracks last night with my Revel Salon 2 speakers as part of an amplifier review. Without EQ, the experience with Caldera was simply not there. Tracks that made me drool last night were "meh" without EQ. Turn on the EQ and you get the bass response I heard last night (and a bit deeper actually). The rest did not mimic the speaker response but at least was another high-fi experience. People who like the stock sound of the Caldera really need to do this comparison of an excellent speaker against what this headphone is producing. I am confident they would re-think their idea of "house sound" as we have measured above.
I also compared to my headphones that match the target and they too had superb bass that again, Caldera without EQ lacked.
Conclusions
Objectively it is clear that Caldera deviates significantly from what research tells us is highly preferred frequency response. That is fine but company needs to conduct its own research to see if their target is more performant. In my subjective and objective testing, I find that to not be the case, wasting what seems to be beautiful physical design. Fortunately we have EQ and fix its errors since its distortion is very low. And once there, have an excellent sounding headphone that looks great and is comfortable to wear.
I can't recommend the ZMF Caldera without equalization. With EQ, it sounds excellent but whether it is worth $3,500, you have to decide.
Manufacturer SPECIFICATIONS:
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The Caldera is absolutely gorgeous to look at. It is lightweight and with its large cup, very comfortable to wear.
EDIT: owner let me know that it has stock lambskin perforated pads.
The large cups allowed almost instant fit on my GRAS 45CA headphone measurement rig. I am always happy when that happens.
ZMF Caldera Headphone Measurement
As usual we start with the headphone frequency response measurement and comparison with our target:
OK, I get the flattish bass response but what is up with the three troughs above 1 kHz? Watching company video, they talk about their house sound but one has to be quite daring to choose a response like this. Fortunately the big areas should be relatively easy to fill in with EQ:
The large drivers produce very little distortion even at highly elevated levels:
There are some narrow band errors though which would have bee nice to iron out:
I forgot to mention the messiness above 10 kHz which we also see in Group Delay:
As expected from planar magnetic drivers, impedance is essentially flat:
Combine that with average sensitivity and you have a headphone that is pretty easy to drive compared to a lot of its competition:
ZMF Caldera Listening Tests and Equalization
First impression out of the box was inoffensive but pretty boring sound. There was almost no deep/sub-bass response so that was the first low hanging fruit to fix with equalization:
That alone made a remarkable difference. But the job needed to be completed with the three other filters to fill those holes. Once there, I liked the effect very much but thought the sound was a big bright so took down the peaks a bit. With the complete package, the transformation was dramatic as you can imagine. There was impressive bass and excellent detail and quite good spatial effects.
This testing was more exacting than usual in that I had listened to the same test tracks last night with my Revel Salon 2 speakers as part of an amplifier review. Without EQ, the experience with Caldera was simply not there. Tracks that made me drool last night were "meh" without EQ. Turn on the EQ and you get the bass response I heard last night (and a bit deeper actually). The rest did not mimic the speaker response but at least was another high-fi experience. People who like the stock sound of the Caldera really need to do this comparison of an excellent speaker against what this headphone is producing. I am confident they would re-think their idea of "house sound" as we have measured above.
I also compared to my headphones that match the target and they too had superb bass that again, Caldera without EQ lacked.
Conclusions
Objectively it is clear that Caldera deviates significantly from what research tells us is highly preferred frequency response. That is fine but company needs to conduct its own research to see if their target is more performant. In my subjective and objective testing, I find that to not be the case, wasting what seems to be beautiful physical design. Fortunately we have EQ and fix its errors since its distortion is very low. And once there, have an excellent sounding headphone that looks great and is comfortable to wear.
I can't recommend the ZMF Caldera without equalization. With EQ, it sounds excellent but whether it is worth $3,500, you have to decide.
Manufacturer SPECIFICATIONS:
- Impedance: 60 Ohms
- Driver: 80mm with CAMS Patent Pending technology
- Weight: 490 - 550 (weight varies depending on Chassis)
- Sensitivity: ~95dB/mW
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
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