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IEMs Single DD vs Multiple Drivers

Last thing: be careful with those graphs because they can be misleading and are compensated on the JM-1 curve. Putting them in overlay on the Harman curve (see photo), in my opinion Blue 2 does the opposite of what you are looking for.
At first glance it seems very screaming and closed and has that depression around 200 Hz (which I hated on Red but here it is worse) that takes away body from the timbre to give you the impression of detailed mids. It seems like an improvement in the extension of the treble compared to Red, but a Downgrade in the rest and in any case I do not see real upgrades compared to Zero2.
In the photos there is also the comparison compared to Zero2 with EQ, IE200 (there you have a real upgrade on everything but especially on the treble) and Performer 5, for example.

You will have time to think about it. For the rest I am happy if I managed to make you useful in some way.
I see what you saying. I might have not been completely true to you, or maybe now after you point out those stuff, there are few things that aren't "perfect" so to speak with the PEQ on the Zero 2.

I had to cut down the 15000 Peak from 7 to 5 db, and the 9500 to from 5 to 4.5 db. Still of course missing the extension, but on quite of few songs the high can get a bit harsh. You cant really see the difference on the graph, but those slight cuts make it a bit more less sharper. It's like slight painful-pleasure to listen to, if you get me.

Blue 2 treble extension looks good, but overall the harman bump needs to be trimmed down for me and probably that dip in the 200s to be raised (which i havent tested, but by judging from your replays i think you are getting a grip of my likings). Maybe the slightly calmer air will be to my taste?

The Performer 5 looks great overall, its even on sale atm for 180$, but should i risk and blind buy it, until i'm not sure exactly where i am in the upper range? Reviews look great though.

The Hexa somehow matches pretty well the Zero's PEQ, just no bass, there is another Truthear set called Pure, which is basically Hexa 2. Feedback about it is very positive, but no idea what's its signature.

From what i can understand from you, if the FR isn't really far from your preferred taste (give or take 4-5 db) and mostly if above 10k its in your sweet spot, you can make any IEM (if the drivers allow it) to be EQ in 98% to each other, right? Maybe with silicone tips the graph would of look differently, or no? My Zero's with those Foam tips from Aliexpress sound very muffled, completely different and unenjoyable.



P.S - If the other fellow forum member doesn't take your invitation offer, i might! I love pizza (had a girlfriend which was joking me that i can eat pizza for a living :D ), vauge speed limits ( I'm in love with 458 Italia, still kicking my butt missing the chance to drive one) and in the process you might actually really help me find my IEMs, oh and i'm not that far from Milan, just 2 hours flight.
 

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I am pretty sure our ear channels change in shape while we are chomping down on our pizza preferences just to make my point about the limit the use case for IEMs imposes on us as well as the IEM's capabilities... :)

I own 3-driver Shure SE535 (the follow-up model got savaged my Amir's recent test) and honestly don't think they sound that much better than the single driver Sony WF1000-XM4 that are my walk-around go-tos these days.
Well, I wasn't talking about ANY multidriver IEM (Shure is almost 19th century), but about the best ones around as compared to the best single DDs around.
 
Here, Fascism ended several decades ago and therefore the freedom of self-determination, making different choices and having different tastes, is very important, which is why we have a cuisine with infinite choices and it is reflected in all other sectors (in reality they are common characteristics with the whole Mediterranean up to Spain). We are proud of our culture and we ourselves detest some aspects of it, but we are not so "closed". My invitation always remains valid :)
Sure, go right ahead and eat what you want, put pineapple on it or whatever. ;)
 
Agreed, yet whenever I try to convince others that putting banana and curry on pizza like we often do locally, I get shot down. A good pizza chef can make this combination work very well. But if you were to get a ****** pizza using these ingredients in Sweden, it'd still be a ****** pizza and not representative as to why it is beloved here.

My GF regularly orders "Hawaiian Pizza" with pineapple on it. As mentioned her pizza choices cause regular friction. But she has never been as close to axe murder as when ordering a pizza with pineapple on it :p. Who wants their desert served on pizza crust???
 
I am pretty sure our ear channels change in shape while we are chomping down on our pizza preferences just to make my point about the limit the use case for IEMs imposes on us as well as the IEM's capabilities... :)

I own 3-driver Shure SE535 (the follow-up model got savaged my Amir's recent test) and honestly don't think they sound that much better than the single driver Sony WF1000-XM4 that are my walk-around go-tos these days.
I have some problems with Headphones, including the heat that remains in the pavilions (today the temperature was 12°. See you this summer) and the broken seal when wearing glasses.
With IEMs I can get the sound I want and the comfort. On the road I either use my IEMs connected to the BTR17 with my PECs inside (a Qudelix with a screen and much more powerful) or I use the TWS Nothing Ear 2024 which in my opinion sound very good and have a parametric E.Q. in the proprietary app. In the end, every solution has its reason to exist
 
Well, I wasn't talking about ANY multidriver IEM (Shure is almost 19th century), but about the best ones around as compared to the best single DDs around.
In my case. IEMs are confined to less than ideal listening environments. Pre-Covid I used to travel a lot for business so I tried to create some "reference" configs. It was pre-ASR participation so the SE535 paired with a Dragonfly DAC (oh the horror! :p) were admittedly the reference. Perhaps it is because of that I kept checking Bluetooth options until they became pretty capable. For me there is no going back to wired for anything when I am on the move anymore. At home I do wired headphones but they are over the ear. My wired IEMs lead very unused lives these days, poor things.
 
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My GF regularly orders "Hawaiian Pizza" with pineapple on it. As mentioned her pizza choices cause regular friction. But she has never been as close to axe murder as when ordering a pizza with pineapple on it :p. Who wants their desert served on pizza crust???
Nutella Pizzas are fairly popular deserts here. They're... not very good in my opinion, but I wouldn't balk at a banana, chicken, curry & pinapple pizza myself. So what do I know.

I think this thread is kinda going the same way as every other "IEM tech" thread. Yeah, you might like some IEM and how they implemented tech X. All the more power to you, others might disagree.

IEMs are such a personal, finicky sound source. Either they work in your ear, or they very much don't. Yes, the basic frequency response seems to be nailed down by the cheapest of IEMs today but that's just not the entire story. But it sure is a large part of it (if not the largest). Personally, I've never heard any difference between multiple driver IEMs and single driver ones - if the frequency response is close enough to forget it between swapping between IEM pairs.
 
I mean well extended treble without many strong peaks and resonances. The most well known examples are the Truthear Nova and the famous Moondrop Variations.
have you ever tried IE600? For me Moondrop Variation has everything except smooth highs. Unnatural timbre, sibilant vocals, non-existent weight of notes but with good bass, percussion instruments are a mess and among other things many have presented an imbalance of the channels in the highs.
In terms of timbre you can feel the incoherence between the various drivers (KE4 is much better in that sense) and even working with E.Q. the highs remain sibilant and hard. The implementation of the EST driver is quite precarious.

The highs are better on HEXA in my opinion... If I make you listen to IE600 you will start crying because they are so beautiful then XD. We have different tastes, it's normal, but I would never exchange IE600 with Variation even taking into consideration only the highs. The EST implementation is not perfect even on Monarch mkIII but still good in a $1000 IEM. Again, I agree that it's harder to control the highs with 1DD, but some IEMs can still do it really well with a bit of thoughtful acoustic engineering.
 
Nutella Pizzas are fairly popular deserts here. They're... not very good in my opinion, but I wouldn't balk at a banana, chicken, curry & pinapple pizza myself. So what do I know.

I think this thread is kinda going the same way as every other "IEM tech" thread. Yeah, you might like some IEM and how they implemented tech X. All the more power to you, others might disagree.

IEMs are such a personal, finicky sound source. Either they work in your ear, or they very much don't. Yes, the basic frequency response seems to be nailed down by the cheapest of IEMs today but that's just not the entire story. But it sure is a large part of it (if not the largest). Personally, I've never heard any difference between multiple driver IEMs and single driver ones - if the frequency response is close enough to forget it between swapping between IEM pairs.
I've always eaten Nutella pizza since I was a kid. Nothing is bad if there's Nutella :).
Ferrero is 2 km from my house and 25 years ago some employee would take out the faulty products (badly printed label...) and give them to us. As we grew up we discovered the existence of pussy and so we didn't go there anymore... but now the employees can't take anything out anymore.:(
 
have you ever tried IE600? For me Moondrop Variation has everything except smooth highs. Unnatural timbre, sibilant vocals, non-existent weight of notes but with good bass, percussion instruments are a mess and among other things many have presented an imbalance of the channels in the highs.
In terms of timbre you can feel the incoherence between the various drivers (KE4 is much better in that sense) and even working with E.Q. the highs remain sibilant and hard. The implementation of the EST driver is quite precarious.

The highs are better on HEXA in my opinion... If I make you listen to IE600 you will start crying because they are so beautiful then XD. We have different tastes, it's normal, but I would never exchange IE600 with Variation even taking into consideration only the highs. The EST implementation is not perfect even on Monarch mkIII but still good in a $1000 IEM. Again, I agree that it's harder to control the highs with 1DD, but some IEMs can still do it really well with a bit of thoughtful acoustic engineering.
These seem to be extremely subjective impressions. All the measurements I know of speak another language.
For the Variations, you just need to EQ down the 3 kHZ peak by a bit and that's it. The treble of the IE600 has wild swings, good luck in EQing this properly.

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These seem to be extremely subjective impressions. All the measurements I know of speak another language.
Sorry if it sounds rude, or silly, either way you guys more often than not put to much meaning into measurements. As with pizza there are aspects that could be measured, but won't tell anything relevant.

First, the shape of treble is formed by internal cavities in the IEM, the nozzle, the tip, and mechanical filters at certain positions (see HEXA). The driver arrangement is another factor, but not the only one. Then it goes onto your ear canal, and blocks it which makes specific resonances that depend on the former, and then last on your very personal physiology. Your physiology determines the shape of treble curves at the ear drum when listening naturally too, but under quite different circumstances. It is never alike the infamous target curves.

Second, why should a driver of 1cm diameter not radiate 20++kHz linearly? It can do that, and will do that, and in order to follow "target curves" the treble is cut off at will.

As I pray for some time now, the measurments of headphones and IEMs in particular must show peaks and dips. Can't reiterate my sermon--never got a response that confirmed an understanding ... :(
 
These seem to be extremely subjective impressions. All the measurements I know of speak another language.
For the Variations, you just need to EQ down the 3 kHZ peak by a bit and that's it. The treble of the IE600 has wild swings, good luck in EQing this properly.

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You see, you obviously need to learn the language better. The IE600 graph is not due to a worse control of the treble, but on the contrary it is due to a careful tuning. All those depressions between 2 and 10 kHz are not there by casuality, especially the depressions at 6 kHz and 8 kHz, but controlled and obtained through the Helmholtz resonance chambers placed on the nozzle and you go to destroy them through the E.Q.? Basically you take a significant slice of the cost of that IEM and throw it out the window. Buying a Maserati to make it sound like a Golf seems smart to you? If you want to have that kind of post E.Q. tuning (very simple to obtain) why spend more than 150€? It is obvious that a much more complex system will be much more complex to transform, but it is not a defect as you show it, on the contrary...
Also regarding Variation, that peak at 3 kHz is wanted and you are paying for the implementation of more drivers to have that.

Why spend all that money to have a distinctive feature (features that you may or may not like) and then eliminate it to have a "normal" curve that any good IEM between 25€ and 150€ can have? It's crazy! It's like spending 4000€ for a DanClark headphone whose cost is all in the excellent engineering to get to have those features and then eliminate them with the E.Q.
You get a HE400se for 110€ that has "standard" tuning, low distortion and do whatever you want with it. What are we talking about? For me it's bad audio knowledge + bad financial management in one post.
 
Sorry if it sounds rude, or silly, either way you guys more often than not put to much meaning into measurements. As with pizza there are aspects that could be measured, but won't tell anything relevant.

First, the shape of treble is formed by internal cavities in the IEM, the nozzle, the tip, and mechanical filters at certain positions (see HEXA). The driver arrangement is another factor, but not the only one. Then it goes onto your ear canal, and blocks it which makes specific resonances that depend on the former, and then last on your very personal physiology. Your physiology determines the shape of treble curves at the ear drum when listening naturally too, but under quite different circumstances. It is never alike the infamous target curves.

Second, why should a driver of 1cm diameter not radiate 20++kHz linearly? It can do that, and will do that, and in order to follow "target curves" the treble is cut off at will.

As I pray for some time now, the measurments of headphones and IEMs in particular must show peaks and dips. Can't reiterate my sermon--never got a response that confirmed an understanding ... :(
In principle I totally agree with you. With any type of driver you can get almost anything you want, potentially. The problem is that with 1DD the treble management is still more difficult to manage. With many drivers that work on specific frequencies, it is much easier (see Hexa). If you try to build yourself an IEM (I made some especially in the Covid period), you will see that to get a good result with a multidriver, it will be easy (relatively) if you have a little patience. I challenge you to do it with 1DD. All 1DDs over 5€ a pair will in many cases be able to reach even 40 kHz out of the shell, but once inserted the problems begin and the treble is there but it is totally messy and with the filters and the distance of the driver from the nozzle, you can amplify or suppress broadband frequencies. All the unwanted depressions and peaks will remain there. The only solution is to dampen the highs, because it is better to have less than to have them but messy. Then yes, you can do everything with 1DD, but you have to design and build a shell with very specific characteristics and a Driver with very specific characteristics, but it takes many hours, tests and above all money. Almost all IEMs, especially Chinese ones, use "standard" shells among the existing types, existing drivers and they do nothing but match the best and many times they still get very good results, I'm not saying no. A company that makes excellent 1DD is "Final Audio" and they produce 6mm shells and drivers by themselves, in fact they do not resemble any IEM on the market, but the "A line" (famous for having spectacular images and soundstage) goes from a minimum of € 120 up to € 2000 (only the drivers cost € 250 in 2017 and the dome was pure Beryllium, not coated PET) and paradoxically the cheapest is the one I like the most. I have never seen a 1DD with well-tuned treble and highs under 100€ and it is not difficult to understand why.

As for peaks and valleys, if well implemented and dosed they are essential to emphasize certain frequencies without the defects (airy and well extended highs but without sibilance and harshness, for example) but they must be controlled with precision. In many cases they are just unwanted peaks, but too expensive and complex to manage for certain product ranges.
 
As for peaks and valleys, if well implemented and dosed they are essential to emphasize certain frequencies without the defects (airy and well extended highs but without sibilance and harshness, for example) but they must be controlled with precision. In many cases they are just unwanted peaks, but too expensive and complex to manage for certain product ranges.
I appreciate your professional clarification. One point I have still. An IEM circumvents the head's shape, especially the pinna. It has to simulate it in terms of frequency response. But that shape is an individual trait of humans. IEMs need to be tuned or equalized to the user. If tuned in the factory a variety of options needs to be offered, that a person can chose from, given that an optimum is the goal.

This applies to the resonances in the upper treble likewise. The problem is harder, but luckily of lesser impact. As it seems to me, people are less sensitive to tamed peaks and dips, even if they do not match the individual HRTF perfectly, because the common noises present in the upper register are for one pretty broadband, and second mostly short lived. Not the least the HRTF changes a lot with incidence angle, and more rapidly the higher the pitch.

It is well understood, that multi driver designs could be tuned to more complicated shapes more easily. Question is, if that helps any individual, and in case a tighter match is desired, if it wasn't better done with electronic equalization--to taste, if that is really available.
 
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Single DD IEMs are the way to go.
I'm not convicted. I use my IEMs daily and I've had numerous 1DDs clogged and usually replacement filter aren't available or are proprietary. Secondly, I discovered a tuning style in my current main IEM which I haven't found in an 1DD IEM, yet. For 1DD to be great it should have all the benefits the of hybrids IMO, currently it doesn't. You might want to point at distortion metrics, but that doesn't negate the all the issues. Theres a possibility that audibility thresholds for real audio content could negate the low-distortion benefits, even more so when you factor in frequency masking.
 
Why aren't single planar driver IEMs the way to go?
Cost versus performance, same as with full size loudspeakers.

I'm not convicted. ... For 1DD to be great it should have all the benefits the of hybrids IMO, currently it doesn't. You might want to point at distortion metrics, but that doesn't negate the all the issues. ...
Which issues, or virtues do you refer to? The original post was (watch the condition "If the tuning is the same ..."):

Current trend in IEM design seems to be multiple drivers in the shell, with the more the better. The Simgot Supermix 4 has 1 DD + 1 BA + 1 Planar + 1 PZT, for example. If the tuning is the same as an IEM with just 1 DD, do these combinations offer anything more? Or in fact, are they actually worse given the complexity of the design?

I suspect you’re best off buying a 1 DD design with FR you like, and that gives a good seal in a shell you like the design off, and that fits in your price range; and that there’s no benefit to expensive multi-driver designs? But I have no evidence to prove this.
I cannot agree more. Except for special demand, example given an urge to just collect collector's items in fancy shells. I do not speak against that, it can be fun; I ordered the Hexa, but couldn't get past its distortion profile in the end. I let go the Zero:Red also, but because of its industrial design that I had chosen the Hexa for, and so forth.

Finally, it depends on the 'preference', a personal taste that may be based on sonic properties. To find a match to that significant head related transfer function of your's is hard, even if one would once stabalize on such a preference, which is hard to begin with. We see it with equalization all the time--people e/q to an on-paper "target" that is by design guaranteed to not match and express delight.
 
Cost versus performance, same as with full size loudspeakers.
Maybe not dirt cheap like Zero:2, Gate or Chu, however planar driver IEMs aren't a novelty anymore and the prices are perfectly reasonable (many of them cost less than 100 EUR) and thus uncomparable to the exotic and rare Magnepan speakers that cost thousands.
 
Maybe not dirt cheap like Zero:2, Gate or Chu, however planar driver IEMs aren't a novelty anymore and the prices are perfectly reasonable (many of them cost less than 100 EUR) and thus uncomparable to the exotic and rare Magnepan speakers that cost thousands.
I was thinking of a more generalized principle, but didn't tell. The DD was found to be simple, successful, flexible, and cheap. So the attention gravitates towards it, which accelerates its adoption and optimization until a point where alternatives can't compete anymore. In single or multiple criteria, as with the Magnepan, alternatives are quickly left behind.
 
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