High efficiency 2-way vs. 3-way

vilayez

Member
2010-07-26 11:28 pm
Hi, everyone.
So far I have always built low sensitivity speakers.
My current speakers are 3 way classic, the system is active through minidsp 4x10Hd
Seas DXT Tweeter
Seas Excel W12CY001
Seas Excel W22EX001
Two Klipsch subwoofer

Now I would like to build high sensitivity speakers. I would like to have a live music sensation, with a great punch in the drums.
My question is the configuration, and I would like to know your preferences.

First option:
Compression driver + 12 "Woofer + Subwoofer
Fc 1200Hz Fc 80Hz

Second option:
Compression driver + 5-6 "Mid + 12" Woofer + Subwoofer
Fc 2000Hz Fc 500Hz Fc 80Hz

Thank you for your attention.
 

Brett

Member
2002-01-07 6:02 pm
Subwoofer has two general definitions: PA and HT, so it depends on how low you want to go. PA is generally 40Hz as that covers most music, but if you want to go lower, then you'll need a different approach.

The first I've done many times and is typically 15/8/1 + WG. The last 2 were;
- JBL2226, ported 40Hz, AE TD10M, QSC152 WG and DE250CD
- AE TD15X sealed, Faital 8HX200 coax; these are still being finalised.
I also have a bunch of other drivers to make a 4 way, just because I can.

There are a number of decisions you need to make before proceeding to decide where the compromises will be. LF extension, xover points & slopes, directivity etc.
 

vilayez

Member
2010-07-26 11:28 pm
Thank you very much for the answers.
My idea is to keep the Klipsch subwoofer for use in the last octaves. The use is only for stereo music.
My question is whether a 12" speaker is capable of reproducing the mid-zone with the same quality as a smaller diameter speaker.
Using a 6 or 8 "midrange speaker, you could use a 1" compression driver that would work in a more comfortable area of the spectrum, with a cutoff frequency near 2000Hz. But I don't know if it means a better sound or it is better to directly pair a 12 "with a compression driver.
The minidsp allows me to choose the slopes at the cutoff frequencies.

I would like to be able to use a 15 "speaker, but the listening room is the living room, and my wife would not be very happy with the size of that speaker :D

Regards.
 

hweb

Member
2011-09-19 8:39 pm
MA, USA
Compression driver crossed to a 6" mid is probably a bad idea. You want to match the directivity of the mid and tweeter at the crossover point or things tend to sound weird. You cannot match the power response of the two drivers at crossover if their directivities are not similar. If the on-axis has flat response the off axis will be lumpy (or vice versa). In order to match a 70° horn/waveguide with a 6" mid you will need to cross at close to 3kHz. Probably higher than you would like. A 10" mid (like the very capable JBL 2123) would be around 1.5kHz - a lot more reasonable.

So then I ask myself "why not just go with a 12 - 15" woofer and go 2-way"? A 15" woofer (like the JBL 2226) would cross around 1kHz and a 12" about 1.3kHz. Seems to make a lot more sense to me. But not just me. YMMV...
 

vilayez

Member
2010-07-26 11:28 pm
Compression driver crossed to a 6" mid is probably a bad idea. You want to match the directivity of the mid and tweeter at the crossover point or things tend to sound weird. You cannot match the power response of the two drivers at crossover if their directivities are not similar. If the on-axis has flat response the off axis will be lumpy (or vice versa). In order to match a 70° horn/waveguide with a 6" mid you will need to cross at close to 3kHz. Probably higher than you would like. A 10" mid (like the very capable JBL 2123) would be around 1.5kHz - a lot more reasonable.

So then I ask myself "why not just go with a 12 - 15" woofer and go 2-way"? A 15" woofer (like the JBL 2226) would cross around 1kHz and a 12" about 1.3kHz. Seems to make a lot more sense to me. But not just me. YMMV...

Thanks for the clarification.
Precisely what I wanted to know are the advantages and disadvantages of the two options that I have in mind.
The question I have is if a speaker with a 12 "+ compression driver with its directivity will only allow me a narrow listening point. I listen to the music many times while doing other tasks throughout the living room, with what I don't always listen in the best place. For this reason I felt that the option of a 12 "+ 6" + compression driver could help thanks to the dispersion of a smaller speaker but I may be wrong.
Greetings.
 
Punch.

I find 12", 15" or 2x15" (most punch) run wide open (down) crossing 750-1200hz to a compression driver.
Run a sub with it (flip phase for most punch).

Better integration 60hz drum (possibly) instead of running through 80-200hz crossover point.

Crossing a 12 at 1.2khz, if the horn is wide enough, will give 90 degree dispersion.

So cone area and a sharp leading edge (horn) helps too.
 
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hweb

Member
2011-09-19 8:39 pm
MA, USA
The examples I gave above offer a listening window of ±35°. If your speakers are 2m away from you (probably too close, IMHO) your listening window is only about ±1.2m. Still probably wider than your couch. If you go to a listening distance of 4m you now have a window of about ±2.3m which is pretty big!

Where you hear horror stories about small listening windows are with exponential horns (whose directivity narrows with increasing frequency) or with large planar drivers (like ribbons) that have very narrow vertical directivity. Use a constant directivity (CD) waveguide and you'll have no issues with too narrow a listening window.
 

vilayez

Member
2010-07-26 11:28 pm
Punch.

I find 12", 15" or 2x15" (most punch) run wide open (down) crossing 750-1200hz to a compression driver.
Run a sub with it (flip phase for most punch).

Better integration 60hz drum (possibly) instead of running through 80-200hz crossover point.

Crossing a 12 at 1.2khz, if the horn is wide enough, will give 90 degree dispersion.

So cone area and a sharp leading edge (horn) helps too.

Thanks for such a direct response.
It seems that option 12 "+ compression driver is winning.
Due to the high Fs of a high sensitivity speaker, to be able to link with a subwoofer I suppose I will need a bass reflex enclosure.
Any suggestions on suitable drivers for my project?

Thanks a lot
 

vilayez

Member
2010-07-26 11:28 pm
The examples I gave above offer a listening window of ±35°. If your speakers are 2m away from you (probably too close, IMHO) your listening window is only about ±1.2m. Still probably wider than your couch. If you go to a listening distance of 4m you now have a window of about ±2.3m which is pretty big!

Where you hear horror stories about small listening windows are with exponential horns (whose directivity narrows with increasing frequency) or with large planar drivers (like ribbons) that have very narrow vertical directivity. Use a constant directivity (CD) waveguide and you'll have no issues with too narrow a listening window.

Thank you very much for the clarification.
The most complicated part of the matter seems to me to be to choose the type of horn, there are many different types ....
 

camplo

Member
2019-02-25 2:27 am
Punch.

I find 12", 15" or 2x15" (most punch) run wide open (down) crossing 750-1200hz to a compression driver.
Run a sub with it (flip phase for most punch).

Better integration 60hz drum (possibly) instead of running through 80-200hz crossover point.

Crossing a 12 at 1.2khz, if the horn is wide enough, will give 90 degree dispersion.

So cone area and a sharp leading edge (horn) helps too.

Norman can you explain why you feel 60hz is better intergration vs "80-200hz"
 
can't.

not the crossover point.

If I remember, a low chunk of drum is 60hz, then all the higher stuff that comes with it.

I just noticed using 12-24db crossover, drum runs didn't sound right to my ears (crossing 80-200hz, couldn't try lower).
Since then, a deep 2-way or a 2-way run with a sub (not crossing over lower bass from the 2-way), sounded better to me.

Voice, maybe 150hz crossover is fine to me, but you hear something funny going on through the bass guitar range, and especially drum runs down. I think it is the phase wrap through the crossover point.

I have yet to hear a time aligned (6db) bass crossover, but should work as I am a 6db fan.
 
What You and your Family experience at the main listening seats must be MUSICAL MAGIC or there is very little reason for DIY.

GOAL: Stereo front 3-way 30Hz - 18kHz controlled directivity 3-way speakers, plus rear stereo Klipsch subwoofers

Sketch your room + seating positions + room treatments and run a few simulations.
==============
I would use a great 12" in a low diffraction SEALED cabinet with a horn tweeter, and add sealed+equalized front woofers.
----------
FRONT STEREO 3-way pair: 1" CD Horn + 12" midbass + room equalized woofers
---Consider a design like the Tweek Geek BMF-1 with side-side counter-force 12" woofers.
You can use your KLIPSCH SUBS for the first experiments, but plan for new front subs.

REAR STEREO pair of subwoofers:
---room equalize rear placement of your stereo Klipsch subwoofers
====================

I'm still a fan of the Tweek Geek BMF-1 style speaker design. 24Hz to 18Khz @93db/watt $606 for drivers. The BMF-1 stands 43”high x 16”wide x 20”deep. Reduce depth with H46" W18" D17" cabinet.

34 Best Tweek Geek'''s BMF Speaker in the making images | Loudspeaker, Flooring, Geek stuff

A 3way 24Hz to 18Khz will cost you....$606 for drivers from PartsExpress + 100Hz Bi-amping
-Faital 12PR320 sealed midrange with -F3 ~100Hz cost ~$230,
-B-52 PHRN-1014 [Part # 299-2303] 1" Horn 10" x 14" Bolt-On waveguide cost $14,
-Peerless 1.75" DFM-2544R00-08 coated Ti-diaphragm compression driver cost $62
----option the 1" B&C DE250 mylar dome compression driver costs $104,
-plus two $150 Dayton RSS315HF-4 12" counter-force subwoofers (one amplifier per woofer)
-------------------------
$606 for drivers
------------------------
Best value: Passive crossovers for the TM and biamp at 100Hz LR4 to the two 12" subwoofers.
----------Lower Cost----------
The $130 12" Eminence Delta Pro 12A woofer is frequently used.
=============

diysoundgroup $310 HTM-12 uses an Eminence DeltaLite 2512 with a light weight NdFeB magnet, and SEOS15. CNC front baffle. $40 cabinet flat pac
 

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vilayez

Member
2010-07-26 11:28 pm
Thank you for the options you offer me "LineSource".
The Faital Pro PR320 seems like a good option, and I can buy it at a good price in Europe.
I had thought about using the Faital in a closed box and crossing it with a subwoofer at 100-120Hz, but the comment of "Norman Bates" makes me doubt and it may be better to use a bass reflex enclosure to be able to perform the cut at 60Hz
Regards.
 

hweb

Member
2011-09-19 8:39 pm
MA, USA
Agree with Linesource (and others) about the B52 horn (parts-express 299-2303) being a great performer. Likewise either of the Peerless larger compression drivers offer great performance. I prefer the 1.75" diaphragm model if you will use active DSP crossover (which you absolutely should) as you might need some delay on the mid-woofer and some PEQ to hammer the response flat. I'm not crazy for the DE-250, but that's a personal choice. I also like any of the Radian compression drivers, but they are much more than $62!!!

I would also agree that a sealed cabinet is the way to go. You can always EQ the bass response as you wish with the DSP. Sealed or vented, the ultimate determinant of bass response will be the cone area and Xmax of the driver (assuming room and placement are constant). In any case, it's a good idea to keep the <80Hz stuff off your mid-woofer to avoid intermodulation distortion.

As far as <80-Hz is concerned; use 2 or more subs placed around the room. Start with FBQ or FBM positioning if possible (rarely possible in a real room). Move the subs around until they sound good. Each sub individually will excite some room mode (resonance). There's almost nothing you can do about that. But having multiple subs placed such that each excite resonances at different frequencies fixes up the bass nicely.

Once you understand this principle, it's easy to see why multiple subs work better. This is precisely why I DON'T like to have subs integrated with the main speakers - you can't move the subs (to fix up the bass) WITHOUT moving the mains.
 

Brett

Member
2002-01-07 6:02 pm
I'm still a fan of the Tweek Geek BMF-1 style speaker design.
That's a well thought out design there LS.
I've had something similar sketched up for a while now, but have not got around to building it because of other projects and an injury last year. PRV version of the same flare, DE250, AE TD10M and sealed and EQd LAB12's for the bottom end. Might have to get off my butt and build it now.

LS, do you have any more detail on the force cancelling rods? Looks neater than the threaded rods I've used in the past.
 

vilayez

Member
2010-07-26 11:28 pm
Agree with Linesource (and others) about the B52 horn (parts-express 299-2303) being a great performer. Likewise either of the Peerless larger compression drivers offer great performance. I prefer the 1.75" diaphragm model if you will use active DSP crossover (which you absolutely should) as you might need some delay on the mid-woofer and some PEQ to hammer the response flat. I'm not crazy for the DE-250, but that's a personal choice. I also like any of the Radian compression drivers, but they are much more than $62!!!

I would also agree that a sealed cabinet is the way to go. You can always EQ the bass response as you wish with the DSP. Sealed or vented, the ultimate determinant of bass response will be the cone area and Xmax of the driver (assuming room and placement are constant). In any case, it's a good idea to keep the <80Hz stuff off your mid-woofer to avoid intermodulation distortion.

As far as <80-Hz is concerned; use 2 or more subs placed around the room. Start with FBQ or FBM positioning if possible (rarely possible in a real room). Move the subs around until they sound good. Each sub individually will excite some room mode (resonance). There's almost nothing you can do about that. But having multiple subs placed such that each excite resonances at different frequencies fixes up the bass nicely.

Once you understand this principle, it's easy to see why multiple subs work better. This is precisely why I DON'T like to have subs integrated with the main speakers - you can't move the subs (to fix up the bass) WITHOUT moving the mains.


Thanks "hweb".

I think it's a good option to force the speaker response with ecu.
Unfortunately in the placement of subwoofer I have no options. The current subwoofer supports the three-way loudspeakers that I currently enjoy. For this reason I have thought about building an enclosure that also includes subwoofer, I know it is not the best option but I can do nothing to improve it.
After your help the speaker could be configured as follows:
-FaitalPro HF108 + Horn - Crossover 1200Hz
-FaitalPro 12PR320 Sealed Box - Crossover 60/80Hz
-Dayton Audio DCS305-4 Sealed Box

Would it be a good choice?
Regards
 
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