[marcan]

One of the benefits of headphones is the ability to produce a sufficient acoustic pressure on the full spectrum with ONE driver. If you start with multi drivers speakers (I’m talking about different drivers for different frequencies), you will have phase and time issues between the different drivers. This issue has never been solved (unless you introduce other sonic problems linked to linear phase filters) and I don’t see how it could have been solved for IEM.
You can easily hear this:
•Deeps and peeks in the frequency response
•Lake of consistency (sibilance, you can separate highs from medium and bass of the same instrument)
•Multi-band compression
These problems are particularly obvious on voices.

I bought a Shure multi-driver (don’t know which one) and it was so obvious: Bass and trebles were there but medium was a ruined. So yes you could hear details in the trebles, but completely inconsistent with the medium. I sold them right away on ebay.

I can understand for people using it on a live stage (actually it’s the original market for these multi-driver headphones), but I really don’t see the point buying these kind of headphones, unless you want to damage your ears with huge levels. Technically, for the same price you should always be able to make better headphones with one driver…

 

[xand]

*shrug*

You're right, in that the superfi5pro (2 drivers) sounds worse than both the ety 4p (although this has less bass) and the Ortofon (both of these have 1 driver), but the UE11s definitely sound better than all of the above.

 

[MayaTlab]

I don't really know anything about the technology involved, but I do see what you mean by sound inconsistency.

However, this isn't a caracteristic of multiple drivers only : I don't find the IE8 sound to be particularly cohesive while the Earsonics SM2 are, to me, among the most "dynamic drivers-like" IEMs I've tried... and yet they have two armature drivers.

 

[Young Spade]

Well you should try different phones before dismissing all of them because you didnt like that pair. Maybe try getting a more neutral pair of IEMs and see how you like those?

While reading that it sounded like you were describing a pair of IEMs that was very colored; I wouldnt like the pair you described either.

@xand: Thats probably because the superfis arent even remotely as good as the etys or the ortofons. Dont compare different tier IEMs to create false fact for someones opinion.

 

[marcan]

Quote:

Originally Posted by xand /img/forum/go_quote.gif *shrug* You're right, in that the superfi5pro (2 drivers) sounds worse than both the ety 4p (although this has less bass) and the Ortofon (both of these have 1 driver), but the UE11s definitely sound better than all of the above.

Yes, I have ety's 4 p/s. Great headphones very coherent sound. A bit shy on the bass department tho.

 

[marcan]

Quote:

Originally Posted by Young Spade /img/forum/go_quote.gif Well you should try different phones before dismissing all of them because you didnt like that pair. Maybe try getting a more neutral pair of IEMs and see how you like those?

The technical issue is still there. You can't have a multi driver system without phase problems. However this problem is solved in headphones because you just need one driver. It is understandable if you need a very high sound pressure but not for casual listening.

 

[Lex]

Quote:

Originally Posted by marcan /img/forum/go_quote.gif I bought a Shure multi-driver (don’t know which one) and it was so obvious: Bass and trebles were there but medium was a ruined.

I totally agree, medium was ruined.

 

[marcan]

Quote:

Originally Posted by Lex /img/forum/go_quote.gif I totally agree, medium was ruined.

Actually, it was the E500.

 

[TopPop]

Quote:

Originally Posted by marcan /img/forum/go_quote.gif The technical issue is still there. You can't have a multi driver system without phase problems.

I don't know enough about acoustics to answer this question, but it seems to me that phase shift shouldn't be much of a problem with multidriver earphones and headphones, since the drivers are so close to the eardrum. Shouldn't any phase shift introduced in the wave propagations be negligible at a distance of, say, 2cm~2.5cm, which is most likely a pretty liberal estimate of the distance from the drivers to the eardrum?

 

[marcan]

Quote:

Originally Posted by TopPop /img/forum/go_quote.gif I don't know enough about acoustics to answer this question, but it seems to me that phase shift shouldn't be much of a problem with multidriver earphones and headphones, since the drivers are so close to the eardrum. Shouldn't any phase shift introduced in the wave propagations be negligible at a distance of, say, 2cm~2.5cm, which is most likely a pretty liberal estimate of the distance from the drivers to the eardrum?

On the contrary, if the drivers are perfectly time aligned, then the phase shift will be more noticeable.
Moreover, phase shift from filters are not constant but different according the frequency, so you can't even compensate with a simple phase shift...

 

[SilverCans]

the phase shift would only be an issue at Fc (the crossover point of the drivers) and not at passband frequencies (were the drivers are independent / not overlapping).

 

[semisight]

Quote:

Originally Posted by SilverCans /img/forum/go_quote.gif the phase shift would only be an issue at Fc (the crossover point of the drivers) and not at passband frequencies (were the drivers are independent / not overlapping).

Yes. Assuming the Fc points are the same for the low pass of the "upper" driver and high pass of the "lower" driver, I think there would be a phase shift of 90 degrees? Somebody correct me if I'm wrong.

 

[ajkda]

why worry so much just enjoy the music

 

[Young Spade]

Quote:

Originally Posted by ajkda /img/forum/go_quote.gif why worry so much just enjoy the music

I had no idea this whole issue was relevant, but I do agree with you to some extent. However this is interesting and I'm reading some articles about it right now. Nothing wrong with educating yourself

 

[marcan]

Quote:

Originally Posted by SilverCans /img/forum/go_quote.gif the phase shift would only be an issue at Fc (the crossover point of the drivers) and not at passband frequencies (were the drivers are independent / not overlapping).

You are right. Problem is you have at least two octaves that are smeared. You can use a steeper filter but you will add more distortions. With two drivers chances are that the frequency of the crossover is in the mediums, which is particularly audible for the human ear. So you can add a third driver in order to have two crossovers frequencies in a less sensible area but it means more octaves smeared and more distortions…