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Why are single drivers disliked to such an extent by most in this forum?

EQ can correct some FR aspects but not the beaming part.
An example is the Bose 901. This uses 9 FR drivers (no whizzer cones) and relies on reflections mostly to obtain a somewhat flat-ish response (and using considerable EQ) but is room and placement dependent.

For loudspeakers they have inherent to the design difficulties. For headphones (excursions, beaming etc. and weight being smaller) this is not that much of an issue.
With speakers it has to be a compromise of surface area, max. amplitude and cone material/stiffness and break-up that are the challenges. There is not a single one that does it all admirably.
From a time alignt/phase coherent behaviour does a singel driver has advantages?
 
From a time alignt/phase coherent behaviour does a singel driver has advantages?
It could when the distance between the driver(s) and ear is short.
At a larger listening distance this becomes less important.
Of course it can't change directivity which is also an important aspect.
 
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I have never heard a single driver design sound ‘good’.
Is it more challenging to ‘design’ a single driver speaker or an open baffle ?
Keith
 
Hard to combine deep lows (at considerable volume) and high frequencies and get a good dispersion pattern from a single driver.
Easier to make a coaxial driver that is also phase coherent but ... dispersion pattern (as the horn is moving basically) is difficult to do right.
 
off topic, but im not a fan of these questions. They imply the whole forum is just hating on something without giving reason.
If you read the whole thread the reasons are given for questioning the performance of single-driver systems used full range.
 
Hard to combine deep lows (at considerable volume) and high frequencies and get a good dispersion pattern from a single driver.
Easier to make a coaxial driver that is also phase coherent but ... dispersion pattern (as the horn is moving basically) is difficult to do right.

Bose 901 with Dirac. This had been with a Harman style bass boost, at about 4-5 meter listening distance.

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Trying for a 2 m listening distance and being smarter about the target curve (instead of 0, the whole thing is attenuated).

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Yep, you can do that... just measure it 1 meter away from the mic/listening position and you can see the limits of the technology.
Also the 901 uses 9 smaller drivers. A nifty trick to increase the needed surface area for bass volume and smaller speakers generally do treble better.
Various speakers at a distance also can cause interference (comb filtering). Luckily for the 901, 8 of the speakers are pointed to the rear walls and only1 is pointing forward.
Without an equalizer/DSP the 901 sounds terrible.
It is harder to build a speaker that does it all well without any EQ (except for perhaps some corrective parts in a passive filter). I guess that's what this thread is about.

Have heard the 901 a few times and while the effect is fun I can hardly call this an exceptional sounding speaker when it comes to sound 'delicacy' etc.
It does have something going for it.
 
A fullrange supported by TML, like Ted Jordan's "The Wall" is not unusual, as far as moderate SPL ist acceptable.
 

Pearl Acoustics Sibelius​

They sound really good, but boy the price
While I find many speakers that cost $5000 to $7000 offensively expensive, nothing screams ripoff more than cheap drivers:
mounted in a simple box:
1720622840271.png

Yes, Harley Lovegrove fits new aluminum cones to the chassis, no that doesn't justify the price.

They sound pleasant to me. But they don't work for my preference, and even if I thought they sounded great there are too many great sounding speakers that cost more like $500 to $700.
 
Yes they may use cheap drivers but they have been ‘designed’ by a ‘designer’ that doesn’t come cheap!
Keith
 
Yes they may use cheap drivers but they have been ‘designed’ by a ‘designer’ that doesn’t come cheap!
Keith
Maybe, but there are these if one wants to dabble. Designs for enclosures and a plethora of drivers.
 
If you read the whole thread the reasons are given for questioning the performance of single-driver systems used full range.
Yes im sure there are plenty. Its just the way the question is posed. Im sure its not on purpose tho.
 
From a time alignt/phase coherent behaviour does a singel driver has advantages?
The degree to which different frequencies are played out of phase can be seen in the frequency response graph, which for a single full range driver is very chaotic on axis, and at high frequencies, even more chaotic off axis. The irregularities are actually caused by different frequency bands being played at different points in time.
 
Without an equalizer/DSP the 901 sounds terrible.
You could say the same about the JBL M2, 708i, 705i or any Meyer Sound, Genelec or Neumann speaker. :). In 2024, the idea of using DSP as a required element of the speaker isn’t unusual.

It is harder to build a speaker that does it all well without any EQ (except for perhaps some corrective parts in a passive filter). I guess that's what this thread is about.
Agreed. I was just fanning the flames a bit and offering a food for thought perspective. There’s no reason you cannot pair a modern Lii audio design with DSP.

Have heard the 901 a few times and while the effect is fun I can hardly call this an exceptional sounding speaker when it comes to sound 'delicacy' etc.
Sort of. I never was impressed with the 901 in the past, but picked a NOS one for the appearance. Once I brought it home, pairing the 901 concept with *modern* electronics had really stepped up the performance of the game.

Paired with classical music, where you do need bass extension but there is much less high frequencies expected due to normal HF attenuation in a real symphony hall and you get a speaker that sounds better than it has any right to.

In the past, the 901’s would be hooked up without the EQ, with people assuming that the EQ was to season the sound as opposed to a fundamental component of the design.

I agree the concept of single driver speakers doesn’t make sense in the world of modern waveguides. (All my other speakers are Meyer Sound right now.)

Still, I don’t think the Bose 901 is worse than the delicacy of a Lii Audio or Eclipse single driver speaker.

That said, other than appearance there is very little that is superior of a single driver direct radiating Lii or Eclipse over a conventional speaker. At least with the 901, you get unique spatial effect that cannot be reproduced by simply turning around a regular speaker to face the wall.
 
You could say the same about the JBL M2, 708i, 705i or any Meyer Sound, Genelec or Neumann speaker. :). In 2024, the idea of using DSP as a required element of the speaker isn’t unusual.


Agreed. I was just fanning the flames a bit and offering a food for thought perspective. There’s no reason you cannot pair a modern Lii audio design with DSP.


Sort of. I never was impressed with the 901 in the past, but picked a NOS one for the appearance. Once I brought it home, pairing the 901 concept with *modern* electronics had really stepped up the performance of the game.

Paired with classical music, where you do need bass extension but there is much less high frequencies expected due to normal HF attenuation in a real symphony hall and you get a speaker that sounds better than it has any right to.

In the past, the 901’s would be hooked up without the EQ, with people assuming that the EQ was to season the sound as opposed to a fundamental component of the design.

I agree the concept of single driver speakers doesn’t make sense in the world of modern waveguides. (All my other speakers are Meyer Sound right now.)

Still, I don’t think the Bose 901 is worse than the delicacy of a Lii Audio or Eclipse single driver speaker.

That said, other than appearance there is very little that is superior of a single driver direct radiating Lii or Eclipse over a conventional speaker. At least with the 901, you get unique spatial effect that cannot be reproduced by simply turning around a regular speaker to face the wall.
Only heard the 901 once or twice, but I think the benefit of this design is how it puts mids and treble into the reverberant field of the room. We accept as a design ideal that speakers should have restricted directivity with frequency but this is not an ideal, and for some music (like symphonic, hall recordings) getting that midrange and treble into the room is advantageous. This is why people like dipoles as well.
 
You could say the same about the JBL M2, 708i, 705i or any Meyer Sound, Genelec or Neumann speaker. :). In 2024, the idea of using DSP as a required element of the speaker isn’t unusual.
yep ... sortof... the difference being that the DSP is an integral part of those speakers and not an add-on that has to be inserted in the chain.
With the 901 you had to use the supplied equalizer, which added tone control (a bit like one can trim the sound of said actives)
That was just analog EQ (bass and treble boost) and arguably the 901 with a DSP and measurement mic can sound tonally more correct than with the obligatory EQ box that had to be in the loop before the power amp.

There are situations where the 901 works 'pleasantly' enough and can fill a room with sound unlike said active monitors though.

I got the point of it using full range speakers (but with obligatory elaborate and extensive active EQ) to correct the FR.
If that were the real solution there would be many monitors with full range speakers and DSP... would be cheaper too :)

I don't know if many buyers ever used the 901 without the supplied equalizer though. It's only some muffled mids without it.
 
yep ... sortof... the difference being that the DSP is an integral part of those speakers and not an add-on that has to be inserted in the chain.

JBL M2? The 901 EQ box is integral.

They did make the active Bose 901 in later years.


With the 901 you had to use the supplied equalizer, which added tone control (a bit like one can trim the sound of said actives)
That was just analog EQ (bass and treble boost) and arguably the 901 with a DSP and measurement mic can sound tonally more correct than with the obligatory EQ box that had to be in the loop before the power amp.
1720633310872.png


The analog EQ versus a Dirac with the +10 dB Harman bass boost to unEQ’d design actually looks pretty darn similar showing you that it’s not just arbitrary bass and treble boost. The hump around 1-2 kHz in the electrical EQ is also matched by Dirac.

So it really was a JBL M2 style setup where you need a BSS in the between the source and the amp also.

If that were the real solution there would be many monitors with full range speakers and DSP... would be cheaper too :)

I think this is the key point. It is NOT *the* solution, it is *one* solution out of many.

I have looked at what it would take to replicate the Bose 901 with modern full range drivers. Once you add up the cost of 18 top tier transducers, consider the cabinet build, it suddenly gets really expensive.

The Bose 901 is really only a good option in 2024 because used ones can be found for cheap and DSP/amplification is also cheap.
 
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