Erik, Two sides of midrange driver membrane produce the same sound only when you face it straight. At the angle there will be reduction because of the phase shift (longer distance). At certain frequency and the angle it will cancel the sound completely.
Is the 2.5 way speaker the ideal home speaker?
Time for what I hope is another fun thread.
One type of speaker which is actually pretty common but which gets little press / attention here on audiogon is the 2.5 way.
A 2.5 way speaker is almost a 3-way, but it isn't. It is a speaker with 3 drivers, but instead of a tweeter, midrange and woofer (TMW) it lacks a true midrange. The "midrange" is really a mid-woofer, that shares bass duties with the woofer. Often these two drivers are identical, though in the Focal Profile 918 the midwoofer and woofer were actually different drivers with the same nominal diameter (6").
The Monitor Audio 200 is a current example of the concept, but I am sure there are many others. It's also quite popular in kit form. One of the most high-end kits I know of is the Ophelia based on a ScanSpeak Be tweeter and 6" Revelator mid-woofers. I haven't heard them, but I am in eternal love with those mid-woofers. I believe the original plans come from the German speaker building magazine Klan Ton.
However many other kits are also available
But regardless of kit, or store purchased, are you a 2.5 way fan? Why or why not?
Best,
Erik
One type of speaker which is actually pretty common but which gets little press / attention here on audiogon is the 2.5 way.
A 2.5 way speaker is almost a 3-way, but it isn't. It is a speaker with 3 drivers, but instead of a tweeter, midrange and woofer (TMW) it lacks a true midrange. The "midrange" is really a mid-woofer, that shares bass duties with the woofer. Often these two drivers are identical, though in the Focal Profile 918 the midwoofer and woofer were actually different drivers with the same nominal diameter (6").
The Monitor Audio 200 is a current example of the concept, but I am sure there are many others. It's also quite popular in kit form. One of the most high-end kits I know of is the Ophelia based on a ScanSpeak Be tweeter and 6" Revelator mid-woofers. I haven't heard them, but I am in eternal love with those mid-woofers. I believe the original plans come from the German speaker building magazine Klan Ton.
However many other kits are also available
But regardless of kit, or store purchased, are you a 2.5 way fan? Why or why not?
Best,
Erik
Showing 12 responses by kijanki
Erik, my previous speakers were 2.5 ways (Paradigm Studio 60/2). In reality it is two way design with extra speaker for the low frequencies. My new 3 way speakers have much better bass - not by extension, but rather by very natural attack and decay of the bass notes. Disadvantage of any 2 or 2.5 way design is "bending" at the higher midrange. |
What I mean to say is, there is no 1 ideal dispersion pattern. From ESL's to open baffles, to traditional multi-way speakers, some with horns. All have very different radiating patterns, and all have ardent fans.It is not a dispersion pattern for particular speaker but for the group of them. Speakers that have large membrane (2.5 way) will suffer. |
Erik, Few questions. 1. Isn’t crossing at 2kHz or lower in the range of female voice, that has fundamentals between 350Hz and 3kHz? 2. Isn’t crossing below 2kHz to close to resonance of most tweeters? I’ve read recommendation to keep crossover frequency at least 1-2 octaves above tweeter’s resonance. 3. Break-up modes for typical woofer might be around 5kHz. Isn’t cutting at 2kHz too close - especially for 6dB/octave? In comparison my 3-way speakers cut at 230Hz and 3kHz - outside of "sensitive" zone. Also, I agree with you that small sweet spot, caused by beaming, might be advantage in acoustically bad rooms, but that’s only if you listen alone. For me wide sweet spot is very important. If I’m not mistaken beaming for 6.5" drivers starts around 1.5kHz. Crossing at 2kHz or lower might help but you need tweeter with very low resonance frequency. I’m not sure what it is, since I don’t design speakers but suspect that it is around 1kHz. My speakers should beam (6.5" midrange) but they have wide sweet spot. Perhaps weird design of the midrange makes a difference (ferrofluid instead of spider web suspension and the wide flat disk instead of dust cap) http://www.hyperionsound.com/Images/HPS-938.jpg |
Thank you Erik. Link you provided states that range of fundamental for woman voice is 165-225Hz while I found this: http://www.seaindia.in/blog/human-voice-frequency-range/ that states: 350Hz - 3kHz for fundamental frequency - about 15 times higher. I don't doubt Wikipedia and just wonder. Could this be that "typical" voice is in narrower range while soprano can get 15x (almost 3 octave) higher? Perhaps it is "talking" (Wikipedia stated "speech") vs. "singing". I appreciate your comment about "not laser like" start of beaming phenomena - my tweeters might already provide wider dispersion where large midrange speaker starts to beam. |
Erik, Paradigm Studio 60 v2, I had before, was sold at about $1k. It usually means that manufacturer sell them for $500. In my company cost of materials is about 30% of the cost of the product. That would imply $170-200 for three speakers, box, xover etc. I did not like sound of the metal dome tweeter and found it to be one of the cheapest Vifa tweeters available. It is very tempting to build speaker using the best drivers available, including underhung motors etc. Unfortunately I already attempted to replace this Vifa tweeter and to redesign xover with high quality components. The purchase of Hyperion speakers was direct result of this attempt. Perhaps I'll learn more and try again one day. |