Bilavideo
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A FEW (ANGRY) WORDS ABOUT IEM CROSSOVERS
I don't want to belittle all the glamor and mystery being sprinkled and shoveled to the public, but here it is: The "integrated crossovers" referred to in ad after ad are mostly for show. By far, most of the frequency tuning is done mechanically, with filters. I was going to talk about this, using UE as a prime example, but held off out of concern that I'd so offend somebody at UE as to end up on the receiving end of major denunciations.
Then again, any denunciations would only disabuse my thoughts of any false conclusions. So, here's what I've found. Feel free to correct me where I err.
1. For all the talk about "integrated passive crossovers," most of these are token crossovers involving a single, low-cost cap, hooked to one wire going into one driver.
2. The driver being "crossed over" is usually the designated "tweeter."
3. Unlike serious crossovers in loudspeaker systems, none of the drivers used are specialized drivers. The "tweeter," "midrange," or "woofer" is a wide-range driver. In the loudspeaker world, the only manufacturer I can think of with the brass balls to market wide-range drivers as either woofers or tweeters is Bose. I'm not a Bose hater, but I priced the sats in Bose's $3,000 system, the one with pairs of mid/tweets arranged along room corners - with one driver directly at the audience and the other aimed at the ceiling or wall - and their replacements were something like $3/driver. Even Bose's subwoofer substitute consists of a set of cheap wide-range speakers, crammed into a box with various bafflings and then crossed low enough to produce an acceptable mid-bass.
4. Lacking specialized drivers, the best an IEM driver can do is employ a combination of crossover, acoustic filtering and tube tuning to produce the psychoacoustic sensation of "powerful bass." The same holds true of the "tweeters" - none of which are reliable past 7 kHz. You'll get some drivers which can push something into 10 kHz, but it's nothing like 100% and anything promised beyond that is blue smoke and mirrors.
5. On most systems, the "crossover" claim is puffery bordering on outright fraud. Where, in the audio world, would anybody brag about a "crossover" that only affected one driver, the "tweeter," and which then had to be supplemented by various filters? If these "crossovers" are any good, why aren't they employed with the midrange and woofer? How are those drivers being tuned, and if it's really just the filter at work, why do we need a "crossover" for a "tweeter" that isn't really a tweeter and is clearly capable of handling the same signal being sent to the other drivers?
6. There ARE exceptions, though by how much is anybody's guess. The UE 10 and UE 11 wire up more than one driver. The UE 11, in fact, has the most sophisticated crossover - an SMD capable of handling up to four separate frequencies. And why? Because the UE 11 employs four drivers, the last of which is its "subwoofer." Even then, we are taking about first-order crossovers of the simplest design, really nothing to write home about.
WHAT I LEARNED ABOUT UE FROM ITS OWN WEBSITE
(Note: This is not intended as an expose aimed at UE so much as a heads-up regarding what the entire industry is doing. To its credit, UE's top customs push the industry to do better.)
Please understand that I am not here to knock UE, the famed pioneer in selling custom-fit, professional monitors to the consumer. I'm just saying that most of the talk about "crossovers" is hype, and that if most consumers were willing to take the time, they'd discover what I've discovered. Understand that I'm not here to run anybody down. I just have my own agenda, which is to make my own in-ear monitors from scratch. I don't feel like paying these companies their mark-up. I feel like I can do as well or better on my own, even if I've come late to the game and have to learn all this stuff on my own.
What I'm going to show you involves UE because UE at least made it possible for consumers to figure things out for themselves. Most manufacturers do a pretty good job of hiding how things really work. In showing off, UE may have shown too much. Who am I to complain?
UE has a pretty complicated product line, with four series of earphones (Metro, Super Fi, Triple Fi and Custom). In addition, there's no attempt at symmetry within these lines. Unlike Westone, which has four universals and four matching customs (though it doubles the top universal - UM3 - into the W3 and the UM3X while doubling the bottom custom - ES1 into the ES1 and CR1) UE is all over the place. They have something like 4 metros, 8 super fi's, 2 triple fi's and five customs - three of which are practically the same earphone. It's a mess. It looks like Apple before it took Steve Jobs back.
If we look carefully at that product line, certain details and patterns emerge. All of the metros are dynamic drivers. Of the 8 super fi's, only the Super Fi 5 Pro claims to have a "crossover," but what it shows on its diagram looks less like a crossover than an O-ring (haha). http://www.ultimateears.com/_ultimat...o_features.php
In fact, this looks like the "low frequency diaphragm for deep rich bass" displayed in the diagram for the Super Fi 5eb. http://www.ultimateears.com/_ultimat...b_features.php
It gets weirder. UE trots another mysterious "crossover" on its Triple Fi 10. Look at this diagram and what you'll see looks suspiciously like another mechanical device being fobbed off on the public as an "integrated passive crossover." Well, if it does the job, all power to UE, but it's not what people think of as a crossover. But judge for yourself: http://www.ultimateears.com/_ultimat...o_features.php
The first actual picture of something that, to me, looks like an actual electrical crossover is the SMD shown in the diagram for the UE4: http://www.ultimateears.com/_ultimat...tom/ue4pro.php
But look at the fine details. I realize this is a diagram, not a photo, but if you increase the magnification of your screen (from 200% to 400%), you'll notice that this crossover is only serving one driver, the dedicated "tweeter."
Take a look at the UE5 and tell me if it doesn't look like the same arrangement: http://www.ultimateears.com/_ultimat...o_features.php
Now look at the UE7 and tell me what you see: http://www.ultimateears.com/_ultimat...o_features.php
I see one crossover serving what looks to be one driver. It can't be the same crossover serving both drivers, even if you'd like to imagine that little yellow wire heading over to the other driver. What would be the point of having three drivers use the same crossover setting?
It's not till we get to the $900 UE10 that we see a crossover that looks like a real crossover.
http://www.ultimateears.com/_ultimat...o_features.php
Even then, this three-chip crossover is only wiring two drivers. Check the leads. The second driver is a "dual driver" giving the UE10 its status as a "triple driver" phone. But there's only one set of leads for that "dual driver" so the real basis for separate "low and midrange frequencies" is the use of different acoustic filters. To its credit, the UE 10 uses a dual driver with dual sound outlets, something the TWFK doesn't do. This allows the two drivers to have different filters. But let's not kid ourselves about the "crossover." This triple-driver only has two crossover settings - at least electronically.
Now, look at the UE11, the top of the heap at Ultimate Ears and quite possibly the closest thing the earphone world has to a decent crossover: http://www.ultimateears.com/_ultimat...o_features.php
Magnify it well and you'll see that we now have three sets of wires to feed "four" drivers. It has a separate tweeter, a separate midrange and a "dual driver, subwoofer." That "dual driver" is UE's version of the TWFK. To provide a real crossover to these three transducers, UE has broken down and purchased a multilayer SMD, one capable of handling up to four separate circuits.
As far as I'm concerned, this is the only real crossover out there. Everything else is just hype. Try walking into an audio forum and claiming you have an "integrated passive crossover" but it only works with your tweeter, which isn't really a tweeter, just a wide-range driver you've decided to use as a tweeter. They'll ask you how long you've been working for Bose.
(Note: That last jibe at Bose has to do with the company's Herculean efforts to make mediocre materials sound good, which I think they pull off successfully. In point of fact, Bose uses much more sophisticated crossovers than are found in any IEMs on the market.)
I don't want to belittle all the glamor and mystery being sprinkled and shoveled to the public, but here it is: The "integrated crossovers" referred to in ad after ad are mostly for show. By far, most of the frequency tuning is done mechanically, with filters. I was going to talk about this, using UE as a prime example, but held off out of concern that I'd so offend somebody at UE as to end up on the receiving end of major denunciations.
Then again, any denunciations would only disabuse my thoughts of any false conclusions. So, here's what I've found. Feel free to correct me where I err.
1. For all the talk about "integrated passive crossovers," most of these are token crossovers involving a single, low-cost cap, hooked to one wire going into one driver.
2. The driver being "crossed over" is usually the designated "tweeter."
3. Unlike serious crossovers in loudspeaker systems, none of the drivers used are specialized drivers. The "tweeter," "midrange," or "woofer" is a wide-range driver. In the loudspeaker world, the only manufacturer I can think of with the brass balls to market wide-range drivers as either woofers or tweeters is Bose. I'm not a Bose hater, but I priced the sats in Bose's $3,000 system, the one with pairs of mid/tweets arranged along room corners - with one driver directly at the audience and the other aimed at the ceiling or wall - and their replacements were something like $3/driver. Even Bose's subwoofer substitute consists of a set of cheap wide-range speakers, crammed into a box with various bafflings and then crossed low enough to produce an acceptable mid-bass.
4. Lacking specialized drivers, the best an IEM driver can do is employ a combination of crossover, acoustic filtering and tube tuning to produce the psychoacoustic sensation of "powerful bass." The same holds true of the "tweeters" - none of which are reliable past 7 kHz. You'll get some drivers which can push something into 10 kHz, but it's nothing like 100% and anything promised beyond that is blue smoke and mirrors.
5. On most systems, the "crossover" claim is puffery bordering on outright fraud. Where, in the audio world, would anybody brag about a "crossover" that only affected one driver, the "tweeter," and which then had to be supplemented by various filters? If these "crossovers" are any good, why aren't they employed with the midrange and woofer? How are those drivers being tuned, and if it's really just the filter at work, why do we need a "crossover" for a "tweeter" that isn't really a tweeter and is clearly capable of handling the same signal being sent to the other drivers?
6. There ARE exceptions, though by how much is anybody's guess. The UE 10 and UE 11 wire up more than one driver. The UE 11, in fact, has the most sophisticated crossover - an SMD capable of handling up to four separate frequencies. And why? Because the UE 11 employs four drivers, the last of which is its "subwoofer." Even then, we are taking about first-order crossovers of the simplest design, really nothing to write home about.
WHAT I LEARNED ABOUT UE FROM ITS OWN WEBSITE
(Note: This is not intended as an expose aimed at UE so much as a heads-up regarding what the entire industry is doing. To its credit, UE's top customs push the industry to do better.)
Please understand that I am not here to knock UE, the famed pioneer in selling custom-fit, professional monitors to the consumer. I'm just saying that most of the talk about "crossovers" is hype, and that if most consumers were willing to take the time, they'd discover what I've discovered. Understand that I'm not here to run anybody down. I just have my own agenda, which is to make my own in-ear monitors from scratch. I don't feel like paying these companies their mark-up. I feel like I can do as well or better on my own, even if I've come late to the game and have to learn all this stuff on my own.
What I'm going to show you involves UE because UE at least made it possible for consumers to figure things out for themselves. Most manufacturers do a pretty good job of hiding how things really work. In showing off, UE may have shown too much. Who am I to complain?
UE has a pretty complicated product line, with four series of earphones (Metro, Super Fi, Triple Fi and Custom). In addition, there's no attempt at symmetry within these lines. Unlike Westone, which has four universals and four matching customs (though it doubles the top universal - UM3 - into the W3 and the UM3X while doubling the bottom custom - ES1 into the ES1 and CR1) UE is all over the place. They have something like 4 metros, 8 super fi's, 2 triple fi's and five customs - three of which are practically the same earphone. It's a mess. It looks like Apple before it took Steve Jobs back.
If we look carefully at that product line, certain details and patterns emerge. All of the metros are dynamic drivers. Of the 8 super fi's, only the Super Fi 5 Pro claims to have a "crossover," but what it shows on its diagram looks less like a crossover than an O-ring (haha). http://www.ultimateears.com/_ultimat...o_features.php
In fact, this looks like the "low frequency diaphragm for deep rich bass" displayed in the diagram for the Super Fi 5eb. http://www.ultimateears.com/_ultimat...b_features.php
It gets weirder. UE trots another mysterious "crossover" on its Triple Fi 10. Look at this diagram and what you'll see looks suspiciously like another mechanical device being fobbed off on the public as an "integrated passive crossover." Well, if it does the job, all power to UE, but it's not what people think of as a crossover. But judge for yourself: http://www.ultimateears.com/_ultimat...o_features.php
The first actual picture of something that, to me, looks like an actual electrical crossover is the SMD shown in the diagram for the UE4: http://www.ultimateears.com/_ultimat...tom/ue4pro.php
But look at the fine details. I realize this is a diagram, not a photo, but if you increase the magnification of your screen (from 200% to 400%), you'll notice that this crossover is only serving one driver, the dedicated "tweeter."
Take a look at the UE5 and tell me if it doesn't look like the same arrangement: http://www.ultimateears.com/_ultimat...o_features.php
Now look at the UE7 and tell me what you see: http://www.ultimateears.com/_ultimat...o_features.php
I see one crossover serving what looks to be one driver. It can't be the same crossover serving both drivers, even if you'd like to imagine that little yellow wire heading over to the other driver. What would be the point of having three drivers use the same crossover setting?
It's not till we get to the $900 UE10 that we see a crossover that looks like a real crossover.
http://www.ultimateears.com/_ultimat...o_features.php
Even then, this three-chip crossover is only wiring two drivers. Check the leads. The second driver is a "dual driver" giving the UE10 its status as a "triple driver" phone. But there's only one set of leads for that "dual driver" so the real basis for separate "low and midrange frequencies" is the use of different acoustic filters. To its credit, the UE 10 uses a dual driver with dual sound outlets, something the TWFK doesn't do. This allows the two drivers to have different filters. But let's not kid ourselves about the "crossover." This triple-driver only has two crossover settings - at least electronically.
Now, look at the UE11, the top of the heap at Ultimate Ears and quite possibly the closest thing the earphone world has to a decent crossover: http://www.ultimateears.com/_ultimat...o_features.php
Magnify it well and you'll see that we now have three sets of wires to feed "four" drivers. It has a separate tweeter, a separate midrange and a "dual driver, subwoofer." That "dual driver" is UE's version of the TWFK. To provide a real crossover to these three transducers, UE has broken down and purchased a multilayer SMD, one capable of handling up to four separate circuits.
As far as I'm concerned, this is the only real crossover out there. Everything else is just hype. Try walking into an audio forum and claiming you have an "integrated passive crossover" but it only works with your tweeter, which isn't really a tweeter, just a wide-range driver you've decided to use as a tweeter. They'll ask you how long you've been working for Bose.
(Note: That last jibe at Bose has to do with the company's Herculean efforts to make mediocre materials sound good, which I think they pull off successfully. In point of fact, Bose uses much more sophisticated crossovers than are found in any IEMs on the market.)
