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HBB X KZ PR2 Planar IEM

Vini darko

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After using these for a few days outside and around the house. I've ended up with this warm EQ curve. Definitely agree that upper treble is a touch much for long listening without EQ.
Screenshot_20230530-200654.png
 

charleski

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Got these today (ordered May12) and ran a few measurements on my (poorly calibrated) measurement mic.
It looks like I can confirm the distortion measurements shown by Sharur earlier, though some of this distortion may well be originating in the mic:
DistortionL.jpg

DistortionR.jpg

(red: 2nd, orange: 3rd, yellow: 4th)

I see there's some discussion on headfi about people getting samples with an elevated response from 10kHz on. My sample doesn't have black mesh, indicating it's from the second revision at least (and the drivers appear to be properly aligned). Since my setup isn't properly calibrated the frequency response must be taken with a lump of salt, but it appears not to show the elevated hf some are complaining about:
Matching.jpg

I did 4 separate measures of right and left and averaged them (there was very little variation between runs of the same side). The left was consistently 1dB higher (possibly an issue with the plug - the stock cable is as cheap as others have noted). When I matched the two at 1kHz the L/R matching seems pretty good and the overall response seems comparable to early measurements.

I've been listening to them without any EQ for about an hour and they seem fine, certainly there's no sign of a fatiguing treble with my pair. They definitely require more gain in your system and are about 15dB quieter than other iems at the same level, but I can run them fine from an old Fiio K1 dongle (speced at 75mW into 16ohms).
 

Blorg

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I have the new, high treble variant. It's very bright, no way getting around this, it's extremely bright. I'm not that sensitive over 10kHz but it's very very bright in the high treble, I can't imagine a young person could possibly listen to this. Sharur has his issues but no one who can hear to 20kHz could hack this without EQ, the treble is insane.

I need -6dB high shelf from 8kHz for it to be listenable, and I'm older with poor high frequency hearing.

There are two versions of this, KZ did an initial collab with HBB with reduced treble, found that was too difficult to manufacture quickly and removed the treble damping so it's now back to crazy high treble. It's a total bait and switch.

Old one has this black rectangular damping directly on the driver, new one it is missing. KZ admit this was a change but they deny it affected the sound. But this is nonsense, NO ONE complained about the original having excessive high treble, some even thought it was on the dark side. But lots of people are finding the V2 too bright.

1685925862774.png



g4EKRsu.png


My (new) one vs the old one, it's a treble monster now. Totally different IEM. This is with foam, it's even worse with silicone tips, and it's highly dependent on insertion depth too with silicone.
ErEPTpW.png


Comparison from Paul Wasabii of different measurements, you can see the new ones with the high treble:


HBB commented on it, I think he has accepted there are two versions now:

1686583108586.png


One other point of interest, and very surprising for a planar, is that the PR2 is sensitive to output impedance, and an impedance adapter drops the treble:

12088226.png

This actually fixes the brightness 100% but unfortunately it starts dropping it from 3kHz rather than 8kHz which is where it really needs it. It makes it just a little dark in the 3-8kHz region. The V1 kept the pinna gain in that region but muted the higher treble, I haven't heard it but the graph looks about perfect. With this it is a lot more natural sounding though and part of the "sounding dark" is probably from direct A/Bing with it stock which is insane treble levels.

KZ did mention tweaking the "PCB" in the V2 as well, to compensate for removing the physical treble damper. So there does seem to be an electronic component in the IEM that presumably is what is giving it a non-flat impedance curve, and probably also what makes it so hard to drive.
 
Last edited:

markanini

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I have the new, high treble variant. It's very bright, no way getting around this, it's extremely bright. I'm not that sensitive over 10kHz but it's very very bright in the high treble, I can't imagine a young person could possibly listen to this. Sharur has his issues but no one who can hear to 20kHz could hack this without EQ, the treble is insane.

I need -6dB high shelf from 8kHz for it to be listenable, and I'm older with poor high frequency hearing.

There are two versions of this, KZ did an initial collab with HBB with reduced treble, found that was too difficult to manufacture quickly and removed the treble damping so it's now back to crazy high treble. It's a total bait and switch.

Old one has this black rectangular damping directly on the driver, new one it is missing. KZ admit this was a change but they deny it affected the sound. But this is nonsense, NO ONE complained about the original having excessive high treble, some even thought it was on the dark side. But lots of people are finding the V2 too bright.

View attachment 291779


g4EKRsu.png


My (new) one vs the old one, it's a treble monster now. Totally different IEM. This is with foam, it's even worse with silicone tips, and it's highly dependent on insertion depth too with silicone.
ErEPTpW.png


Comparison from Paul Wasabii of different measurements, you can see the new ones with the high treble:


View attachment 291782
It's not the first time KZ changed things mid production, after sending out review samples that got well received. Well done, Blorg!
 

LearningToSmile

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I have the new, high treble variant. It's very bright, no way getting around this, it's extremely bright. I'm not that sensitive over 10kHz but it's very very bright in the high treble, I can't imagine a young person could possibly listen to this. Sharur has his issues but no one who can hear to 20kHz could hack this without EQ, the treble is insane.

I need -6dB high shelf from 8kHz for it to be listenable, and I'm older with poor high frequency hearing.

There are two versions of this, KZ did an initial collab with HBB with reduced treble, found that was too difficult to manufacture quickly and removed the treble damping so it's now back to crazy high treble. It's a total bait and switch.

Old one has this black rectangular damping directly on the driver, new one it is missing. KZ admit this was a change but they deny it affected the sound. But this is nonsense, NO ONE complained about the original having excessive high treble, some even thought it was on the dark side. But lots of people are finding the V2 too bright.

View attachment 291779


g4EKRsu.png


My (new) one vs the old one, it's a treble monster now. Totally different IEM. This is with foam, it's even worse with silicone tips, and it's highly dependent on insertion depth too with silicone.
ErEPTpW.png


Comparison from Paul Wasabii of different measurements, you can see the new ones with the high treble:


HBB commented on it, I think he has accepted there are two versions now:

View attachment 291782

One other point of interest, and very surprising for a planar, is that the PR2 is sensitive to output impedance, and an impedance adapter drops the treble:

12088226.png

This actually fixes the brightness 100% but unfortunately it starts dropping it from 3kHz rather than 8kHz which is where it really needs it. It makes it just a little dark in the 3-8kHz region. The V1 kept the pinna gain in that region but muted the higher treble, I haven't heard it but the graph looks about perfect. With this it is a lot more natural sounding though and part of the "sounding dark" is probably from direct A/Bing with it stock which is insane treble levels.

KZ did mention tweaking the "PCB" in the V2 as well, to compensate for removing the physical treble damper. So there does seem to be an electronic component in the IEM that presumably is what is giving it a non-flat impedance curve, and probably also what makes it so hard to drive.
What a stupid way to ruin the reputation you were just beginning to recover, ruin your working relationships with content creators, and waste a lot of money spent developing your driver tech(correct me if I'm wrong but they're the only ones using that planar driver as far as I know so I'm assuming it was developed in-house). I get the margins are tight but surely a better way would be to honor the existing preorders, and then just increase the price for the remainder of production if the original damping method was harder(ie more expensive) to do. Really feel bad for HBB here.

I got lucky by ordering on day one and got one of the first 6000 sets with the correct damping mesh, but I'm sure as hell not going to trust KZ in the future.
 

khensu

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That does not bode well... I'm awaiting delivery on a pair. If mine exhibit that problem, I'll be returning them.
 

Blorg

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It's actually still IMO decent for the price and a single -6dB high shelf at 8kHz fixes it and it sounds fine. Do try that. But it's a bait and switch and big disappointment given just how great the original looked, and was reviewed. KZ just can't help themselves. Totally agree they should have just charged more if they had to, this is much worse. How could they have thought it wouldn't be noticed, it's not a small change. And they are flat out lying to everyone complaining about it saying it sounds the same, which only makes it worse.

But it's still very detailed and very technical for the price, and some electronic genres, particularly if you are older, I think you could even hack the treble and it can be fun. Natural instruments, the timbre sounds off though. It's not terrible at all. It's just not the original IEM as promoted in the collab and that got all the rave reviews. It's near identical to the PR1 Pro in the treble, with just a touch less mid bass (that bit is not a negative, it's cleaner, less boomy, actually very close to Harman in the bass now). It's just too bright in the treble, it just goes straight out horizontally rather than falling off. I even think Harman IE falls off a bit too quick, it doesn't need to come down that much. But it needs to come down a bit.

1686590117831.png
 
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charleski

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Just to be clear: my sample doesn’t have the black mesh, but also doesn’t have the nasty high-frequency lift. So the two aren’t linked, but KZ may well have made another change that isn’t visually obvious.

The measurements I made (and all my listening so far) were done using the rather thin stock cable. I thought about buying the chunky 784-core cable on the grounds that less cable resistance is better, but the impedance adapter measurements make me think that might actually not be a good idea.
 

markanini

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I thought about buying the chunky 784-core cable on the grounds that less cable resistance is better
What a waste of copper, you could instead twist on some miniaturized resistors in an adapter plug, if this is the avenue you are considering.
 

Blorg

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Just to be clear: my sample doesn’t have the black mesh, but also doesn’t have the nasty high-frequency lift. So the two aren’t linked, but KZ may well have made another change that isn’t visually obvious.

The measurements I made (and all my listening so far) were done using the rather thin stock cable. I thought about buying the chunky 784-core cable on the grounds that less cable resistance is better, but the impedance adapter measurements make me think that might actually not be a good idea.
I measured the stock cable vs a thicker Xinhs one, it's not a significant difference. Stock might be slightly higher impedance (which actually lowers the treble) but it's a tiny difference. I was trying to swap the cables without disturbing the IEM in the coupler as even a slight difference in insertion actually makes a big difference in the graph. So I did the Xinhs first and then only barely connected the stock one, I thought it might have been from it being a loose connection. This is actually what prompted me to check it with the impedance adapters (easier to swap them and get consistent measurements as they are not on the IEM end.) But either way... not a huge difference and yes, more conductivity with this if you have the bad one is a negative. Although yours doesn't seem as bright.

1686591304631.png
 

charleski

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Stock might be slightly higher impedance (which actually lowers the treble) but it's a tiny difference.
Yeah, given that the cable’s only 1.2m long I suppose you aren’t going to see much change in impedance. But I really don’t like an elevated upper octave, so I’ll stick with the twisty stock one.

What a waste of copper, you could instead twist on some miniaturized resistors in an adapter plug, if this is the avenue you are considering.
I want the exact opposite actually. But braided cables are nicer from a usability aspect and the 784 is only £12 inc tax, which is why I was about to buy it.
 

markanini

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I want the exact opposite actually. But braided cables are nicer from a usability aspect and the 784 is only £12 inc tax, which is why I was about to buy it.
Cables have their purpose, resistance addition has a different purpose. Anywhere where they intersect will either 1. have a tiny effect, or 2. make the cable ridiculously overdimensioned. Only unless the cable maker did something clever...
 

Tarnith

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This set made me look at KZ, but now seeing what people are actually receiving has turned me off ever buying a KZ.

Not sure why they don't raise the price to the point they can better control the QC if that's what's needed. They would still be affordable and with a better treble tuning could still try to undercut most of the market.
 

boswell

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The rubindum magnets are a fairly new thing as far as i can tell. Wonder how they will progate though the industry. Seems that only Chinese firms currently use it as it's a Chinese invention , here's the patent info for anyone whos intrested.
Rubidium is a group 1 alkali metal similar to Sodium and Potassium, ie very low melting point, highly reactive and non magnetic and would not form any stable alloy. The googled article has Rubidium in its title and first few paragraphs. In a reading of the main article there is no mention of Rubidium but Dysprosium and other rare transition metals that do have magnetic properties, I suggest that there has been some confusion in translating from the Chinese and an erroneous text substitution was made. Interested Chemist/Metallurgist.
 

charleski

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This set made me look at KZ, but now seeing what people are actually receiving has turned me off ever buying a KZ.

Not sure why they don't raise the price to the point they can better control the QC if that's what's needed. They would still be affordable and with a better treble tuning could still try to undercut most of the market.
KZ have changed their production methods for this model. We know of at least one change (initial run had black mesh over the driver which disappeared quite early on), but they may have made other changes as well. I ordered mine on May 12 (i.e. a couple of weeks after the initial run of sales) and there was a wait of several weeks before it shipped, so there may have been a pause as they setup a new production protocol.

I have to say that I'm quite satisfied with my pair, the high distortion is disappointing, but I can't say I really hear it. One thing I really do appreciate is the close matching (apart from the 1dB balance shift) between R and L, which is quite uncommon at this sort of price. It's certainly a lot better than some people got with the first run of units. I run them heavily EQ'd to Harman corrected to match my personal preference and have to say that subjectively I find them very pleasant and beguiling: I end up listening longer than I'd planned.

Unfortunately unless someone goes out and buys a bunch from the current production run we won't know if KZ have fixed the problems they had with the first run or if it's still a bit of a crapshoot. They are pretty cheap, though (I think several independent AliX stores are still selling at around the $30 sale price), but I wouldn't buy them at full price on Amazon.
 

Truckasaurus

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I have an original pair with the mesh and they're nothing short of legendary for the price, and have a second pair at the ~$32 price on the way, most certainly a revised pair. I'll be curious to compare them.

What I don't get is that kz changed one piece of foam and now charges like 25% less per pair now. That black piece of foam CANNOT be worth more than ten bucks in labor and materials to apply. If they noticed it was a little expensive to apply, why not just... increase the price to meet it? People (myself included) were RAVING about these and if KZ said "sorry these have to cost $75 to cover costs" they'd still be a spectacular deal. This makes zero business sense.

It seems like KZ has great engineers and truly brain damaged management.

Makes me wish the trn rosefinch wasn't so treble hot. Their amazingly nice, modular cable, great built quality, and custom planar driver for $42 was ready to break the market segment. And TRN build quality is much more reliable. But KZ broke the market and then pissed in their own cornflakes. It won't even matter that it's probably going to be the case that the new, hotter version is still going to be an absolutely obscenely good deal. It's all about how they handled going about it. Utterly puzzling
 

khensu

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Anyone have experience with Aliexpress support? I ordered these back in May. They gave me an estimated arrival of June 14. That date has obviously passed. Their tracking says it left from the shipping partner in Compton, CA on 5/24 on their way to USPS. USPS says they are still waiting for it. Ali support told me I need to check with usps. I haven’t, but I don’t see the point if they haven’t received it.
 

markanini

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Anyone have experience with Aliexpress support? I ordered these back in May. They gave me an estimated arrival of June 14. That date has obviously passed. Their tracking says it left from the shipping partner in Compton, CA on 5/24 on their way to USPS. USPS says they are still waiting for it. Ali support told me I need to check with usps. I haven’t, but I don’t see the point if they haven’t received it.
The seller is in a contract is with their shipping partners, not you. Just tell them you checked out of courtesy, they said they didn't receive it, and that you want a refund, since the goods appear lost by the available information. If it's after the 90 day mark you can't raise disputes.
 

Truckasaurus

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I got the "new" version and good God they ruined them. I LIKE treble. I like a bright, sparkly design. But these are now sharp AND less detailed. The tuning itself isn't even the problem. The whole vibe of the complete package has just been thrown off and they sound horribly, terribly unnatural.

They're sharp and sibilant and less detailed, I love planar weird tamber but these are just not good now. I wouldn't even recommend them for the $30 they're asking. The truthear Hola, CCA cra, or 7hz zero are all better. The base model quarks. The tangzu princess Chang le. All better. Because those all are a cohesive sound. This is unpleasant because it's discordant. Mids sound muffled and muddy, treble is harsh and muddy, midbass and sub bass just somehow enhance the harsh unpleasant treble.

Bummer. They went from being a dominant sub-100 set that I'd recommend to EVERYONE, to something I'll never recommend to anyone.
 

*Cihan*

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Besides the fact that above 10kHz the readings are unreliable, there's surprisingly little content in that region for most contemporary music, and anyone older than a teenager is unable to hear it anyway.

View attachment 286231
I just wanted to mention it without any offense, I'm 38 and I hear 15 kHz yet I understand speech with noise or reverberation much harder compared to an average person. But I hear noise floor and high frequency well.
 
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