[jhelsas]

That's something that I've wondering about for quite sometime now. Etymotic have pulled out some great IEMs, like the HF5 and the ER4 series, but they are all single-BA, and if I remember right, they also use their own proprietary driver.
 
Is there any technical reason why etymotic haven't yet released an dual BA in-ear in the marked or would it (I doubt) only be lack of interest from the public?
 
Who knows, with a bit of wishfull thinking they would manage something in the level (or above?) of a PFE232 or an Westone 4?

 

[average_joe]

Because the ER4 already has "unsurpassed frequency response accuracy and sound quality — 86%+ response accuracy from 20 Hz – 16 kHz."

 

[MrGreen]

Etymotic have stated, fairly publicly, several times that there is no reason to have multiple balanced armature drivers because distortion and frequency response are already low enough, or aren't improved by adding more drivers.

I personally don't know enough about balanced armatures to comment further.


FWIW I would consider the ER4 one of the best (if not the best) balanced armature systems ever made. Better than the westone 4, and several others. YMMV.

 

[ClieOS]

1st, it isn't a proprietary driver. Just a common BA that tuned to Etymotic's preference with acoustic filter, resistors and caps.

2nd, from Don, the man who invented the ER4 himself:

Do you need a dual driver IEM, or did some marketing genius convince you that two drivers are better than one?

The arguement for multiple drivers holds water when there are physical limitations to filling a large room with sound, and not a 1.4cc volume in your ear canal.

What do you plan to gain from dual driver?

 

[soundstige]

The less work each driver is doing (by using crossovers), the quicker the transients can be, from my understanding.
Quote:

1st, it isn't a proprietary driver. Just a common BA that tuned to Etymotic's preference with acoustic filter, resistors and caps.
2nd, from Don, the man who invented the ER4 himself:

 

[ClieOS]

The less work each driver is doing (by using crossovers), the quicker the transients can be, from my understanding.

Maybe, but passive crossover has problems of its own.

 

[jhelsas]

Quote:

1st, it isn't a proprietary driver. Just a common BA that tuned to Etymotic's preference with acoustic filter, resistors and caps.
2nd, from Don, the man who invented the ER4 himself:

 Out of my ignorance, what I thought was that since the BA system have suposely a limited region of the sound spectrum, because of it's non-linear character from the mechanical point of view it would be necessary at least more than one driver to get to cover properly the whole frequency spectrum.
 
 Aparently, I was wrong, but still, if it's not necessary, it remains the question: Why most companies invest in multi-driver design and also why, correct me if I'm wrong, if you compare single drivers from the same line-ups with multi-driver designs, you can hear a diference for better in favor for the multi-driver design?
 
 Would it be only because the companies would be unwilling to tune so they can extract the maximum out their single-driver sistems?

 

[ClieOS]

Do I think single driver can rival multi-BA in SQ? With dedication to R&D, yes. Do I think the reason of multi-BA's popularity is partially due to marketing and easier sell-ability?Most definitely yes. But are these the only reason for supporting either single or multi- driver design? No. I would think the situation is more complex than that.

Before we have IEM, the speaker world has already debating the same question of full-range vs. multi-driver. It is still a topic for people today as it was back then. There are pros and cons on both side and there isn't any clear cut answer that can totally disprove the validity of the other.

 

[belushka]

Because they are still doing good business with 1 BA, they don't need to upgrade. When business starts to fall down, they will release it.
 

 

[MrGreen]

Quote:

Do I think single driver can rival multi-BA in SQ? With dedication to R&D, yes. Do I think the reason of multi-BA's popularity is partially due to marketing and easier sell-ability?Most definitely yes. But are these the only reason for supporting either single or multi- driver design? No. I would think the situation is more complex than that.
Before we have IEM, the speaker world has already debating the same question of full-range vs. multi-driver. It is still a topic for people today as it was back then. There are pros and cons on both side and there isn't any clear cut answer that can totally disprove the validity of the other.

 
As is my understanding, balanced armature drivers do not flex like dynamic drivers, and as such do not enounter issues such as noise and thd when the flex becomes greater with increased SPL. As such, I think cross-overs do not provide this particular benefit to balanced armatures. I think this is the core of etymotics reasoning - they have the frequency response down fine (other reasons for cross overss), and there won't be a change to the noisie performance by adding more.

Maybe I am wrong, I haven't really read too much on balanced armatures.

As for transients being affected I'll have to go ahead and say that isn't the case. A balanced armature producing a 100hz tone and a 1000hz tone will still move at 1000hz, with alterations. Probably an increase in air movement to correspond with the wavelength and phase of the 100hz tone also being played.
 

Warning: LATE night post. Maybe have some errors.

 

[tranhieu]

Quote:

 
As is my understanding, balanced armature drivers do not flex like dynamic drivers, and as such do not enounter issues such as noise and thd when the flex becomes greater with increased SPL. As such, I think cross-overs do not provide this particular benefit to balanced armatures. I think this is the core of etymotics reasoning - they have the frequency response down fine (other reasons for cross overss), and there won't be a change to the noisie performance by adding more.

Maybe I am wrong, I haven't really read too much on balanced armatures.

As for transients being affected I'll have to go ahead and say that isn't the case. A balanced armature producing a 100hz tone and a 1000hz tone will still move at 1000hz, with alterations. Probably an increase in air movement to correspond with the wavelength and phase of the 100hz tone also being played.
 

Warning: LATE night post. Maybe have some errors.

they do, quite frequently in fact, depending on which model you are using. If you ever take a loot at datasheets published by knowles the voltage at which the said driver is measured varies within quite a large range (to BA). Main reason is to control thd and noise.
Moreover due to their mechanism BAs are more inductive than dynamic, resulting in nasty impedance graphs making designing multi order XO a pain.
that said, some well known company here (that I refrain from naming) designed one of their famous iems so poorly that it made me sick when I first opened them up.
 
someone above said the reason for having multi driver iems is because of their limited range. that's one of the reasons, which is mainly because BAs were designed for hearing aid market in the first place, not for us audiophiles, hence the emphasis on the midrange. Some current models can extend well in the upper spectrum but they cost an arm and a leg since audiologists pay less than none attention to those 'hi-end' BAs.

 

[goodvibes]

Quote:

The less work each driver is doing (by using crossovers), the quicker the transients can be, from my understanding.

and that would show up in inner detail. ER4 isn't lacking. Multiple drivers is more for tuning since the ER4 actually is full band for all intents and purposes. Others could use a bit more bandwidth so it's another good reason for multiples in some cases but resolving power has always been a stalwart of BA IEMs. They also tend to have fast rise times. I prefer a bit less etched and slightly warmer sig for instance but that doesn't make the ER4 any worse. It's still a great device.

 

[MrGreen]

Quote:

they do, quite frequently in fact, depending on which model you are using. If you ever take a loot at datasheets published by knowles the voltage at which the said driver is measured varies within quite a large range (to BA). Main reason is to control thd and noise.
Moreover due to their mechanism BAs are more inductive than dynamic, resulting in nasty impedance graphs making designing multi order XO a pain.
that said, some well known company here (that I refrain from naming) designed one of their famous iems so poorly that it made me sick when I first opened them up.
 
someone above said the reason for having multi driver iems is because of their limited range. that's one of the reasons, which is mainly because BAs were designed for hearing aid market in the first place, not for us audiophiles, hence the emphasis on the midrange. Some current models can extend well in the upper spectrum but they cost an arm and a leg since audiologists pay less than none attention to those 'hi-end' BAs.

 
Interesting thank you for the knowledge.

Would you be able to PM me the name/info?

 

[planx]

Ah, posts like these bring forth Head-Fi's most respected and knowledgeable members. As a reference IEM (according to Etymotics goals), I think the ER-4 is their greatest accomplishment and considered perfection in their books. I love my ER-4S and absolutely nothing replaces it. To me, the ER-4 is what music "should" sound like. But everyone gets bored of that very easily so people from Shure, Westone and many more decided to sell IEMs with multiple drivers to make the complete opposite of what music "should" sound like and it was an absolute hit! Honestly, I really like some of the products they created (Shure SE535, Westone UM2, Audeo PFE232 just to name a few) because they filled in the gap of listening pleasure. They achieved what Etymotic couldn't (wouldn't?) achieve and that was a specific sound signature per IEM in their lineup. Think, what Shure, Westone, Earsonics IEMs all sound the same? They might sound similar, but never the same because WHO WANTS TO BUY THE SAME SOUND OVER AND OVER AGAIN? Marketing people, that's why. Compare the UM2 to the UM3X. Very different IEMs targeted at very different potential buyers. I might be very Etymotic biased here, but Etymotic to me is like the ultimate "reference" point in the IEM market. It's sort of a centerpoint. Of course the ER-4S isn't perfect in anyway (cough cough fit and comfort), but to me it's the closest thing to the ultimate reference monitor. The only thing that comes close is the RE272 and possibly a few CIEMs, but even those sound a bit emphasized here and there. ER-4 is no excess, no limiting.
 
Just an opinion from a very bored person on a very hot night in very normal vancouver.

 

[Inks]

I agree completely with the above.