# 2 way or 3 way



## xtinkshun (May 6, 2011)

My family member wants to build some DIY speakers and was asking a question... What is the main difference between 2 way and 3 way speakers and what if he builds a sub? So that go me thinking as well. Instead of building a full range speaker with 2 or more bass drivers, midrange, and tweeter why not just build a monitor style speaker with a midrange and tweeter. Then place it on top of a nice subwoofer for low end bass. 

What are the pro's and con's of each type of build? Lets stick with a DIY design. How about the Statements? They have a full size tower with bass drivers and a monitor style. Would it sound as good or better if he built the monitors and added a subwoofer for the 10hz - 60hz duties? What is the deciding factor, is it the frequency range? 

Looking at B&W, Monitor Audio, Paradigm etc there isn't much difference between the full size and monitor speakers. Would the noticeable difference be in the midrange bass? or would the subwoofer take care of that? Why build a full size speaker if he can build a nice monitor with a subwoofer. There has to be some reason people buy/build full size speakers over monitors.

Let's assume it's a 15" or 18" DIY subwoofer and whatever DIY brand monitor you wish to compare. (the statements were just an example) but he does want something nice, ie seas,peerless,vifa, hivi drivers (hi-end) drivers and a higher end DIY build. up too $1,000 per speaker.


Feel free to use examples of DIY builds or list manufacturers speakers.


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## GranteedEV (Aug 8, 2010)

xtinkshun said:


> My family member wants to build some DIY speakers and was asking a question... What is the main difference between 2 way and 3 way speakers and what if he builds a sub? So that go me thinking as well. Instead of building a full range speaker with 2 or more bass drivers, midrange, and tweeter why not just build a monitor style speaker with a midrange and tweeter. Then place it on top of a nice subwoofer for low end bass.
> 
> What are the pro's and con's of each type of build?


That is a question with a complicated answer. What might be a pro in one 3-way speaker might not be a pro in another. What may be a pro in a given 2-way speaker might be a cone in another. 

At the end of the day it's all a system. You can get poor results either way and you can get great results either way. Where you realistically have to start is by establishing what you're trying to get out of the system as a whole. And when I say system, I mean everything - amplification, room interaction, seating positions, and the listener expectations.

There is no one-size-fits-all solution, no matter how badly we want there to be. 

But I'll start with this basic premise:

Crossovers between different drivers are an inherent, but necessary evil. 

The most simple speaker, then, is of course a *1-way - a speaker with no crossover*. You can equalize a single driver pretty flat and get respectable results. The larger the driver is, the less impressive it'll be up top, for a vast number of reasons that are probably well beyond the average person's understanding (voice coil inductance, diaphragm breakup, surround resonance, off-axis beaming being a few reasons, but not all). The smaller the driver is, the more problems you have at the bottom end of the frequency range - less extension, less efficiency, less maximum output, frequency modulation distortion, etc.

Of course, that does not preclude 1-way speakers from sounding very, very good. Some people will even argue they are "the best" because they do not have a crossover. All the sound is coming from an absolutely single point in space - just like a real life voice will. Start by looking around at some designs, like the Mark Audio Alpair 10:










Can you imagine where it might have an advantage or disadvantage over some big 4-way to take it to the _other_ extreme? 

Ultimately, it becomes a matter of which tradeoffs you're willing to go with. The less crossovers, the less potential for crossover-induced error, but you're further at the mercy of drivers' inherent limitations. I'll say this: I've made a pair of excellent two-ways that can hit SPLs none of my 3-ways can hit, and I've got a pair of 3-ways that can resolve top-octave detail that no other speakers I've heard can. I have no real preference between two-way or three-way without context.



> Lets stick with a DIY design. How about the Statements? They have a full size tower with bass drivers and a monitor style. Would it sound as good or better if he built the monitors and added a subwoofer for the 10hz - 60hz duties? What is the deciding factor, is it the frequency range?


Those 8" woofers on the statements run up to around 300hz give-or-take. Can a small 6" monitor match that between 100hz and 300hz? Those 4.5" mids on the statements handle the 2khz to ~3.5khz range. There are some definite advantages of that approach. For starters you're not relying on a 1" dome to produce in the same range.

So no, it's not just "frequency range". Everything from

- max SPL at a given frequency and by extension, linear-distortion (and non-linear)
- horizontal off-axis response
- ON-axis response
- vertical off-axis response
- electrical impedance
- acoustic phase 

factor into the design.



> There has to be some reason people buy/build full size speakers over monitors.


Of course! And it's very application dependant. Of course below 100hz especially the best placement for bass is rarely the best placement for imaging so subs are always recommended. But subs are not a substitute for speakers' own midbass capability - the ability to seemlessly blend to subs.  Here's a pair of sealed 3-ways that are crossed over to a pair of subs.


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## xtinkshun (May 6, 2011)

Wow, I wasn't expecting such a detailed answer. Thank you.. This will certainly cause me to rethink my options.


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## xtinkshun (May 6, 2011)

Should I be looking at specific drivers? ie, Accuton, Raal, Seas Excel or doesn't it matter...


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## ajinfla (May 10, 2009)

Only if your budget $$ allows. They are certainly not necessary for great sound. But the effect of $$, reputation, expectations and looks, on humans, should never be underestimated. YMMV.

cheers,


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## xtinkshun (May 6, 2011)

You hit the nail on the head.... but does spending more money on expensive drivers equate to "better" sound reproduction or will less expensive drivers be sufficient. Would a person really notice if its a "Raal or Neo" ribbon? Or an Accuton vs. Tang Band mid bass driver? While the B&W 800 Diamond series and Wilson Audio speakers sound incredible I can't justify $20K on a pair of speakers..


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## GranteedEV (Aug 8, 2010)

xtinkshun said:


> Should I be looking at specific drivers? ie, Accuton, Raal, Seas Excel or doesn't it matter...


Drivers might matter under _the most extreme scrutiny_ (we might be talking a single note on a piano might excite an issue in one driver that does not exist in another), but you can make a very good speaker with hundreds of different drivers if they work nicely together to produce good final results. And ultimately "what bothers" you may not even be noticeable to another person (and that's assuming it even exists!) in the same recording. If you haven't done the scrutinizing comparisions yourself, all you're left with is someone else's biased opinion, which doesn't help you the final listener!

In general, I suggest look for midrange / midbass drivers that

- Are stiff and do not contain breakup peaks/nulls within an octave of the appropriate crossover point at their top-end
- Have the x-max to crossover to woofers or subs at their bottom end without too much strain

For tweeters, you should look at

- getting good off-axis matching at the crossover point to the midrange/midbass. Waveguides, such as the ones made by Pellegrine Acoustics, really help in getting this seemless transition compared to flush-mounting when using larger mids.
- getting decent power handling at the bottom end of their range

The rest, is kind of a judgement call and like AJ said, will depend on your starting budget. Don't feel compelled to stretch your budget chasing that last 10% unless you've personally experienced whether that last 10% actually exists. A lot more performance can be squeezed out of getting good system design than out of great drivers - within reason.


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