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Three-way vs two-way plus sub

HooStat

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I was looking at the Mesanovic RTM10 and the Dutch and Dutch 8C. Both talk about having a "subwoofer". I am not getting into a semantic discussion of what it means to be a subwoofer. I am honestly curious how those speakers are functionally different from something like the Genelec 8340 or 8350 plus the 7370 sub (or 2 7360 subs). If you consider all of these to be 2-way speakers that cross over at an appropriate place (100 Hz for Dutch and Dutch and 150 Hz for Mesanovic), it seems to me that the Genelec monitor + subwoofer(s) would be conceptually equivalent. Extending this logic, something like the KEF LS50 Meta (or your favorite monitor) plus some subs and a reasonable cross-over (150 Hz or so) are all just variations on the same theme.

In contrast, the Genelec 8361A crosses over at 320 Hz, which seems like a slightly different approach to the problem of creating a "full range" monitor (term used loosely).

I am ignoring the cardioid aspect of Dutch and Dutch, and the simplicity of the single monitor approach and near field use.

I am curious as to comments from others on this.
 

alex-z

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Ignoring the cardioid ability is a bit silly, at that is a major selling point. Reduced room interaction at low frequencies is a good thing, unless you are working in a heavily treated environment that damps the back wave fully down to 100Hz.

The Mesanovic RTM10 is a good speaker, but the directivity above 3000Hz suffers a bit from the ribbon tweeter with no waveguide.


Genelec speakers or LS50 Meta plus subwoofers falls into the same camp as the RTM10. While excellent choices, they aren't state of the art in the same way as the D&D 8C. Similarly, you may see upper echelon studios go with something like ATC SCM50ASL mounted in-wall. Smoother mid-bass because there is no energy going behind the baffle and interacting destructively.
 

Sancus

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I mean the differences are mostly a result of the fact that the 8361A is a coaxial and the others are not. The 8361A's midrange is limited by the need for it to fit the tweeter in the center, and is limited in excursion as well to avoid disrupting the tweeter too much.
Extending this logic, something like the KEF LS50 Meta (or your favorite monitor) plus some subs and a reasonable cross-over (150 Hz or so) are all just variations on the same theme.

The main difference is that as the speaker designer you get to choose the midrange. So you can ensure that it will "keep up" with the (sub)woofer. And you also get to optimize the crossover of course.

When you add a sub to an existing 2-way, you didn't get to choose the midrange, and so that midrange is not actually optimized. The LS50 is a good example because its woofer is weak all the way up to 500hz, despite being roughly the same size as the 8361A's. Just look at the 96dB distortion for each(8361A, LS50 Meta). So just adding a sub to this speaker doesn't get it anywhere near the capability of an 8361A. Or even an 8351B, for that matter.

Typically, the woofers in 2-ways are (relatively) compromised as midranges because they're designed to play much lower.
 
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HooStat

HooStat

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I think that mentioning the 8361 and Dutch&Dutch 8C is confusing the issue because they each offer some unique features. I completely get that they are different.

For a moment, let's just look at the Genelec 8340 and 8350 with the 7370 sub (or 2 7360 if you prefer). Doesn't that get to a full range solution with a little more extension than most options, and with more control than most 3-ways? The GLM system should be optimizing the cross-over and phase, correct?
 

ernestcarl

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There aren’t that many three-ways extending down to 20-25 Hz so a sub(s) would likely benefit either one anyhow.

And while I sometimes wonder how much I’m missing out by only using two-ways and a sub (how awful is the IMD to human perception at practical listening SPL volumes, really?) for my nearfield use situation, it probably is a non-issue.

The main advantage with automated solutions like GLM is the ease of use. One can get similar xo phase optimization functionality with other free — but more manual — software like rePhase and REW.
 

Chrispy

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Yeah I'd just call them woofers in those speakers....
 
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HooStat

HooStat

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I sometimes wonder how much I’m missing out by only using two-ways and a sub (how awful is the IMD to human perception at practical listening SPL volumes, really?)
I keep wondering the same thing. For sane listening levels using well-engineered speakers, the most important factor might simply be bass extension.
 

Chrispy

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I keep wondering the same thing. For sane listening levels using well-engineered speakers, the most important factor might simply be bass extension.

Or perhaps dealing with superior subwoofer placement options depending on room vs l/r speakers.
 

dfuller

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So, in comparing 3 ways and 2 ways with similar 2034 performance, the 3 ways almost always sound a bit cleaner. Whether this is because of lower IMD or because of some other reason, I couldn't say.
 

Ron Texas

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I mean the differences are mostly a result of the fact that the 8361A is a coaxial and the others are not. The 8361A's midrange is limited by the need for it to fit the tweeter in the center, and is limited in excursion as well to avoid disrupting the tweeter too much.


The main difference is that as the speaker designer you get to choose the midrange. So you can ensure that it will "keep up" with the (sub)woofer. And you also get to optimize the crossover of course.

When you add a sub to an existing 2-way, you didn't get to choose the midrange, and so that midrange is not actually optimized. The LS50 is a good example because its woofer is weak all the way up to 500hz, despite being roughly the same size as the 8361A's. Just look at the 96dB distortion for each(8361A, LS50 Meta). So just adding a sub to this speaker doesn't get it anywhere near the capability of an 8361A. Or even an 8351B, for that matter.

Typically, the woofers in 2-ways are (relatively) compromised as midranges because they're designed to play much lower.
I wouldn't call it weak up to 500. It just doesn't do well @ 96 db. Somewhere between 86 and 96 it is fine and that is all some rooms need. LS50's with a sub are not an endgame dynamic range system, but they work damn well if the room isn't too big or extreme loudness isn't important.
 

Sancus

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For a moment, let's just look at the Genelec 8340 and 8350 with the 7370 sub (or 2 7360 if you prefer). Doesn't that get to a full range solution with a little more extension than most options, and with more control than most 3-ways? The GLM system should be optimizing the cross-over and phase, correct?
Sure, I think an 8350 + sub w/GLM is pretty close to a similar somewhat larger bookshelf-sized 3-way. You are still going to be limited in mid-bass output compared to the really powerful 3-ways though, and there may be more IMD(audibility unknown). Plus you won't have the same LF directivity control that a larger woofer offers, which can make a difference.

The 8C/RTM10 are weird examples because they're both designed specifically for extreme LF directivity control, although the RTM10 isn't quite as much it's still very low CD compared to a normal speaker. So the choices of midrange, woofers, and crossovers are heavily influenced by their controlled directivity goal.

Most 3-ways have much higher crossovers, like the KH420 has a 570hz crossover and even the Revel F328Be, a very large speaker with a very good midrange, has a 240hz crossover.
I wouldn't call it weak up to 500. It just doesn't do well @ 96 db. Somewhere between 86 and 96 it is fine and that is all some rooms need. LS50's with a sub are not an endgame dynamic range system, but they work damn well if the room isn't too big or extreme loudness isn't important.
Well that's easily solved because I was using my definition of weak, not yours ;) 96dB matters to me because even at an average SPL of 80dB, fairly normal listening level for me, I have music that goes up to 100dB+ in certain parts at a listening position of ~2.3m. Plus I also use my system for home theatre. The LS50 would fall apart in this context.

If you are listening at 1m and/or you don't have to worry about such unusually high dynamic range material then I agree it's not a problem. But my point was just to illustrate that adding a sub to an LS50 Meta does NOT make an 8361A, the 8361A is still much more powerful. That is also to be expected given the size and price differentials.

I think the LS50 Meta is a great value speaker fwiw and have said so elsewhere. I might buy a pair for my bedroom or desktop.
 

Somafunk

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My 3 way Dynaudio lyd 48’s and Dynaudio 18s sub sounds way better than my previous 2 way KRK Rokit 7’s and KRK 10s sub, obviously the 4” drivers are giving me all the mid range definition I was missing from the 2 way KRK's but I wasn’t expecting the bass to tighten up quite as much, the two 8” drivers on the LYD’s along with the two opposed 9” drivers on the sealed sub sharpen everything up, an absolute doddle to set up with the presets on the sub.

The big genelecs with their sub and glm software must be pretty much endgame material in an average sized room, I could never afford them but shame you can’t hire them for a few weeks just to hear how the lucky few experience audio.
 

Pearljam5000

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I mean the differences are mostly a result of the fact that the 8361A is a coaxial and the others are not. The 8361A's midrange is limited by the need for it to fit the tweeter in the center, and is limited in excursion as well to avoid disrupting the tweeter too much.


The main difference is that as the speaker designer you get to choose the midrange. So you can ensure that it will "keep up" with the (sub)woofer. And you also get to optimize the crossover of course.

When you add a sub to an existing 2-way, you didn't get to choose the midrange, and so that midrange is not actually optimized. The LS50 is a good example because its woofer is weak all the way up to 500hz, despite being roughly the same size as the 8361A's. Just look at the 96dB distortion for each(8361A, LS50 Meta). So just adding a sub to this speaker doesn't get it anywhere near the capability of an 8361A. Or even an 8351B, for that matter.

Typically, the woofers in 2-ways are (relatively) compromised as midranges because they're designed to play much lower.
What do you mean by limited? And if the mid driver is that compromised, isn't a normal 3-way with midrange that have no limitations better than the coaxial in this context?
 

Sancus

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What do you mean by limited? And if the mid driver is that compromised, isn't a normal 3-way with midrange that have no limitations better than the coaxial in this context?
I mean those are design constraints they had to take into account when designing the speaker. There are dozens of other factors. For example the Neumann KH420 uses a relatively small 3" dome for the midrange and that's probably why it has a higher crossover, because that dome doesn't work well below 500hz. The 8C uses an unusually larger 8" for the midrange to generate the cardioid effect, so that involves different tradeoffs as well.

It doesn't really make any sense to compare speakers at the driver level as a listener. They're a whole integrated system, you get what you get because of a long list of interrelated decisions the designer made.

Personally I think Genelec made the right tradeoffs for my use case(a multi-channel system with mixed speaker sizes). If I wanted a purely stereo system I'd probably have gone for something with cardioid bass over the 8361A/8351B, even at a higher cost. That's because I typically live in apartments with asymmetrical living rooms and I think cardioid bass has more value the less room treatment and more difficult room geometry you have. If you have space for a dedicated, treated and symmetrical room, then cardioid bass has less value, so maybe you make a different decision entirely.

There isn't really any such thing as "better" or "worse" for all situations unless you are comparing speakers that are way outside of the same class.
 

ernestcarl

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What do you mean by limited? And if the mid driver is that compromised, isn't a normal 3-way with midrange that have no limitations better than the coaxial in this context?

As Sancus said, there are always design constraints.

One alternative coax that does not have the same excursion limitation would be something like Fulcrum Acoustic's RM28 -- I'm sure you've already seen me mention it before -- but there's also the trade-off a much less smoothly flat frequency response since it uses a much smaller waveguide that doesn't extend continuously with the rest of the front baffle.

Of course, there are other 2- and 3-ways that aren't concentrically configured and as mid-driver "excursion-limited" like the Genelec Ones that will be able to play louder (e.g. JBL M2). But there are also many more cheaper 3-way speakers the like of KRK Rokit 10-3 G4 that simply aren't gonna cut it in the SPL and distortion department.
 

mmi

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I am in this boat right now. I’ve been researching my main system upgrade for years (with lots of info garnered from here and other sources) and have narrowed down to three way vs two way w/ active sub integration. My shortlist is:

Legend Tripos - 3-way by a local maker (there used to be some more detailed soundstage style on + off axis measurements of different models floating around online, I guess I’d say trust me that they all tracked his highly gated on axis charts)

Neumann KH 80 + 750

Philharmonic BMR - but unfortunately he won’t ship to AUS

I guess I can try listen to the Tripos as he lives in my state, and maybe a music gear store will have the Neumann setup.
 

ethanhallbeyer

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I mean the differences are mostly a result of the fact that the 8361A is a coaxial and the others are not. The 8361A's midrange is limited by the need for it to fit the tweeter in the center, and is limited in excursion as well to avoid disrupting the tweeter too much.


The main difference is that as the speaker designer you get to choose the midrange. So you can ensure that it will "keep up" with the (sub)woofer. And you also get to optimize the crossover of course.

When you add a sub to an existing 2-way, you didn't get to choose the midrange, and so that midrange is not actually optimized. The LS50 is a good example because its woofer is weak all the way up to 500hz, despite being roughly the same size as the 8361A's. Just look at the 96dB distortion for each(8361A, LS50 Meta). So just adding a sub to this speaker doesn't get it anywhere near the capability of an 8361A. Or even an 8351B, for that matter.

Typically, the woofers in 2-ways are (relatively) compromised as midranges because they're designed to play much lower.
Would an 8351b with sub get close to an 8361a? Say of you prefer the smaller size speakers, start with a smaller room (20'x18') but possibly move some day to a larger space.
 

Sancus

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Would an 8351b with sub get close to an 8361a? Say of you prefer the smaller size speakers, start with a smaller room (20'x18') but possibly move some day to a larger space.

It just depends on the content. But I would say 8351B + subs > 8361A. Subs, especially 2+, just give you much nicer low bass when setup properly. The 8351b is still a ~8" woofer class 3-way monitor, so it's not "weak" for mid-bass by any sane definition.

My 8351B + 2x sub multi-channel setup is capable of playing >110dB at the ~2.5m listening position without any strain at all, which is frankly more than I need.

The 8361A is the speaker for people who just don't want to deal with subs, or for extremely large rooms with 4+ meter listening distances if you can't afford the W371A. Nothing wrong with that, they both have their use cases.
 
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