2 way vs 3 way

[MrBoat]

I've been searching the archives and google with this question. I even came across a video from the audioholics guys touching on this very subject. But the examples they showed looked pretty exotic to my eyes and really didn't answer my question beyond the obvious. If there is other threads here that cover this, perhaps even of that from a minimalistic approach, that would be fine too.

My question is, if a person has no room for a subwoofer, or a center speaker, can a 2 way speaker sound as good as a 3 way with 2 channel listening? I understand about the crossover having to do less with a 2 way as a tradeoff, or an equalizer in this equation. That makes sense. But, if you could only put two speakers in a room and wanted to listen to quality audio with enough bass and midrange, could this be achieved with a 2 way speaker? Would you perhaps choose a 2 way with a larger woofer? What would this do to the midrange?

The reason I ask this is, I notice that a lot of floor speakers are 2 way but with multiple woofers that are the same size and just a tweeter and those seem to rely on a subwoofer. Yet they claim excellent bass and midrange and hi's. It's hard for me to imagine a driver handling all the bass and the midrange simultaneously without stepping on itself. I recall Advent speakers back in the day with a rather large woofer and just a tweeter but I don't remember what they actually sounded like or what I may have been comparing them to at the time.

Another scenario perhaps. If you had a multi-channel amp, say a 5.1, if you needed more pronounced midrange from 2 way speakers, could you perhaps use the other channels just for some stand alone midrange emphasis without going the surround route, or perhaps better put, adding the 3rd of the 3 way after the fact?

 

[shadyJ]

It's hard to do a two way speaker with very good bass extension. You need a very wide band woofer with a large cabinet and very good tweeter, and that is expensive. Much less expensive just to do a three-way at that point. You definitely do not want other speakers in a surround sound system trying to help out the mids when playing back stereo content. I can't imagine that sounding good. If you want more pronounced mode from two-way speakers in a two channel system, just EQ the mids.

 

[zieglj01]

It is about the finished (designed and engineered) product as a whole. Some 2-ways can sound better than 3-ways. Poor crossover work can effect a lot of speakers.

 

[MrBoat]

It's hard to do a two way speaker with very good bass extension. You need a very wide band woofer with a large cabinet and very good tweeter, and that is expensive. Much less expensive just to do a three-way at that point. You definitely do not want other speakers in a surround sound system trying to help out the mids when playing back stereo content. I can't imagine that sounding good. If you want more pronounced mode from two-way speakers in a two channel system, just EQ the mids.

That's what I am discovering. I am considering DIY that uses better components than some of the more affordable mass production options so that should help.

A couple of things make me hesitant. Coming primarily from 3 way speakers which was pretty much the only options in my price ranges, and the overwhelming consensus centered around bass management and subwoofers.

On my pc desktop, I bought a set of rather cheap, 2.1 Logitech speakers from best buy. The mids are only 2" and they kind of surprise me. Not audiophile quality by far, but bearable and they are actually only 1 way without the sub. By that logic, on the surface anyway, a mid-large size, 2 way floor speaker ought to be capable, especially with more professional components.

 

[MrBoat]

It is about the finished (designed and engineered) product as a whole. Some 2-ways can sound better than 3-ways. Poor crossover work can effect a lot of speakers.

I am inclined to believe this. Again, many of the 2.1 desktop speakers are in effect, no more than a two way setup. In my current desktop for example, the mids and highs are handled by a single speaker, while the bass is handled by a single sub. Granted there is separation between the sub a mid drivers, but still, if this is achievable to even bearable levels with cheap components, great components ought to work that much better.

 

[TLS Guy]

The optimal speaker is a one way. A single driver is the only approach that allows optimal phase and therefore time response. It is fortunate that the human hearing is relatively insensitive to the serious transgressions and errors introduced by multi driver speakers with crossovers.

It has been pointed out for many years that crossovers separate the fundamental frequencies from their harmonics, and the transgression is massive. The fact that hearing is relatively insensitive to these gross errors does not mean they are insignificant and should be dismissed out of hand.

The ideal moving coil loudspeaker should have one single cone. No lesser person than the great audio engineer Paul Voight realized this in the early thirties and developed a high fidelity full range driver and loaded it with a corner horn. This came into production in 1934. It is widely recognized as the worlds first high fidelity loudspeaker.

In the early fifties GE briefly got into the speaker business and produced an 8" aluminum cone full range driver, that was quite good, and was used in the Decca corner horn designed by Dr A.R. Bailey and Ralph West.

One of these was the second speaker I built. It is actually not a horn, but a folded Voight pipe. It was successful enough that it launched the Transmission line project at Radford audio in the early sixties.

At the same time because of the success of these full range drivers, and the fact that Peter Walker's Quad electrostatic speaker had taken the audio world by storm interest in better speakers really picked up.

Quad ESL 1957

At Goodmans loudspeakers their chief engineer Ted Jordan developed a 4" aluminum coned full range driver with a unique suspension. The cone weighed 6 grams. Unfortunately the owner of Goodmans died and the company was sold and turned into a junk brand and most of the employees including Ted were fired.

Ted went into business with the company accountant Leslie Watts and produce the driver. I heard it in 1959 and was smitten with it. Unfortunately the drivers had a life of about 20 minutes. Ted was a brilliant audio engineer but not a good mechanical one. I guess I consider myself an intuitive mechanical engineer and worked with Leslie Watts for around 14 years or so improving the driver and marketing it in Canada.

At our little Eagan residence we have converted a small bedroom into a small sitting room/ listening area and game room for the grandchildren. I'm using just one of these Jordan Watts drivers per side, 2 drivers in all.

The sound is smooth with good detail and depth of image. The bass is much better than other speakers of similar size, in fact F3 is mid forties. In that small room you would actually vow there was a sub.

Fortunately these drivers and Ted Jordan's subsequent designs have not been forgotten. These drivers and speakers had a strong market in the Far East, probably because rooms are much smaller.

In the last years Mark Audio have been producing drivers based on Ted's principles.

The problem with these drivers is power limitation (15 Watts) and oil canning of the cone due to over excursion.

Mark Audio have now been helped by some very good transducer engineers and further developed this driver and found a way to prevent damage from over excursion.

Because of the problems of crossovers, especially in the speech discrimination band, I now detect a renewed interest in wide band drivers. This has always been a goal at B & W in their 800 series, bit until their new D3 series the mid range driver has been plagued with cone break up at the upper end of the pass band.

Recently Dennis Murphy has produced a three way design using this novel 3" full range driver from the UK as a wide band mid range.

So the essence of all this is that no crossover is the ideal and in small rooms is a very viable solution.

Two ways built with wide band bass/mids can be very successful especially if the crossover can do minimal violence to phase and therefore time and make for a seamless transition.

Three ways are very often problematic, because the mid has nowhere near the bandwidth required, so both crossovers end up where the ear is most sensitive and you end up with multiple problems. Power handling of a lot of mid range drivers is also frequently inadequate. A good mid range needs a bandwidth of at least 4 octaves and be able to be crossed around 350 to 400 Hz on the lower end, and preferably at 4KHz on the top end. Those are few and far between.
The development of more good full range drivers to be used as mid range drivers will make this much easier. They will also improve two ways by raising the crossover out of the speech discrimination band.

Lastly you can get excellent bass from smaller drivers, but not good bass and high power handling. If you want good bass and high power then it makes the case for a three way, or a good two way and a sub.

In a small room I think you can make the case strongly for full range drivers. In small rooms you tend to often be close to the speakers, and so driver integration issues can be a problem with close proximity. For a small room I think either a full ranger or a two way is most appropriate.

 

[MrBoat]

Most excellent post, TLS Guy. I appreciate it.

 

[ski2xblack]

TLS, what are your thoughts about compression drivers for the mid-range in a three way design? That would address the bandwidth, power handling, and dynamic range requirements you mention. Drawbacks?

 

[Swerd]

My question is, if a person has no room for a subwoofer, or a center speaker, can a 2 way speaker sound as good as a 3 way with 2 channel listening?

I understand about the crossover having to do less with a 2 way as a tradeoff, or an equalizer in this equation. That makes sense. But, if you could only put two speakers in a room and wanted to listen to quality audio with enough bass and midrange, could this be achieved with a 2 way speaker?

Yes, without question. A good example of a 2-way floor standing DIY design is described in detail here http://forums.audioholics.com/forums/threads/new-diy-mtm-towers-designed-by-dennis-murphy-and-paul-kittinger.68531/. That DIY design was made by two excellent speaker designers, Dennis Murphy and Paul Kittinger.

Would you perhaps choose a 2 way with a larger woofer? What would this do to the midrange?

With today’s speaker drivers, I’d go no larger than a 2-way using 6” to 7” woofers. As you pointed out, these designs often use two woofers and one tweeter. Two woofers don’t go to lower frequencies than one of the same size, but they do get twice as loud as one woofer, and they can achieve that loudness with less cone movement and less distortion.

Any loudspeaker acts as a point source for sound. Simple physics dictates that if the point source is smaller than the wavelength of the sound being produced, it will radiate out from the point source evenly in all directions. In home audio, widely radiated sound is a major factor in creating a natural sound. With two speakers operating in stereo, this can create a realistic sounding image of musicians who seem to emerge from the speaker cabinets and sound as if they are within the room.

One of the major problems in audio is that the wavelengths involved can be similar in size to cones of the drivers. As the sound wavelength gets similar in size to, or smaller than the diameter of a driver, the sound gets projected in a progressively narrower pattern. Instead of broadly projecting sound, the driver beams it.

For example, look at the manufacturers for the woofers used in that DIY design, the SEAS ER18RNX https://www.madisoundspeakerstore.com/seas-woofers-6-7/seas-prestige-er18rnx-h1456-7-reed-paper-cone-woofer/

They show 3 frequency response curves, one measured directly in front of the driver, on-axis, and off-axis at 30° and 60° angles. Notice that as the frequency increases, those off-axis curves drop at lower frequencies than the on-axis curve. Importantly, the 30° off-axis performance is similar to the on-axis performance as high as roughly 2 kHz. Above 3 kHz, it drops by more than 3 dB, a noticeable drop. The conclusion is that these 6½” (18 cm) woofers can produce good mid range as high as 2 to 2½ kHz. Fortunately it is not difficult to find tweeters that can perform that low without distorting.

In general, as the diameter of a woofer gets larger, the less it can perform in the range where you can directly cross over to a tweeter. Those Advent speakers you recall, with an 8” woofer and an early design dome tweeter, are a good example of how 2-way speakers with too large a woofer, fail in the midrange. Those 8” drivers can produce decent sounding midrange if you listen directly on-axis. But off-axis that midrange falls off enough to make those speakers sound like there is a hole in the mid range. They were limited in how well they could create a good stereo image.

By today’s standards, you will find many good quality 2-way speakers with one or two woofers roughly 5” to 7” in diameter. Larger woofers almost always require a mid range driver. Fortunately, the woofers in that DIY design, mounted in the cabinet described in that DIY link, can produce bass with an F3 (the -3 dB point) of 35 Hz, and useful bass as low as roughly 31 Hz. For most music that works without a subwoofer.

 

[TLS Guy]

TLS, what are your thoughts about compression drivers for the mid-range in a three way design? That would address the bandwidth, power handling, and dynamic range requirements you mention. Drawbacks?

Well JBL seem to have tamed the compression driver and horns in their new pro line. However of the current ones available to the DIY market, I don't think I would like to sit though Wagner's ring cycle with a speaker using one of those as a mid.

The ATC mid has good power handling and a couple of 6.5" units that I use do very well even if I have to crossover a little lower than I would consider ideal. There is always a compromise to be made somewhere. I can't complain though as my rig gives a very faithful.

 

[MrBoat]

I keep hearing mention of the requirement for the sound of a speaker replicating a live performance, as if the musicians were in the room. What about the other end of that spectrum, where some listeners actually prefer the end result of studio recordings? That in spite of such altered efforts not being exactly genuine, still, there is a quality to it that many people find enjoyable, even if they don't know that's what they like about it.

Secondly, what about the "presence" associated (is this something of my imagination?) with larger woofers and cabinets, in spite of some of the scientifically measured ideals with actual sound projection. For instance, the JBL speakers I own are technically way too large for my space and even though they are called "floor speakers", I have them up on end tables in the corners of the room to clear the sofas. But still, their presence ends up overcoming my environment and lack of ideal acoustical treatments within my space. I am 8 feet away from the speakers that are using my sofa and loveseat as whatever damping they provide, with me positioned in my chair as the final acoustic treatment. My new speakers would also ideally sit atop these end tables. They are safer from the grandchildren there as well.

BTW, I don't mind being told I have this all wrong and that's why I am here. If I'm missing out, I am all for improvement. But there's a limit to how much someone like me may want to know. Is kind of like building a hot rod. Where you take a normal car, rebuild the engine towards performance and make it faster, which it ultimately is, but as you get used to the new found performance, you find yourself wishing you had gone for the stage 3 kit instead of the two. Next thing you know, you're shopping for a Corvette.

 

[MrBoat]

Yes, without question. A good example of a 2-way floor standing DIY design is described in detail here http://forums.audioholics.com/forums/threads/new-diy-mtm-towers-designed-by-dennis-murphy-and-paul-kittinger.68531/. That DIY design was made by two excellent speaker designers, Dennis Murphy and Paul Kittinger.
With today’s speaker drivers, I’d go no larger than a 2-way using 6” to 7” woofers. As you pointed out, these designs often use two woofers and one tweeter. Two woofers don’t go to lower frequencies than one of the same size, but they do get twice as loud as one woofer, and they can achieve that loudness with less cone movement and less distortion.

Any loudspeaker acts as a point source for sound. Simple physics dictates that if the point source is smaller than the wavelength of the sound being produced, it will radiate out from the point source evenly in all directions. In home audio, widely radiated sound is a major factor in creating a natural sound. With two speakers operating in stereo, this can create a realistic sounding image of musicians who seem to emerge from the speaker cabinets and sound as if they are within the room.

One of the major problems in audio is that the wavelengths involved can be similar in size to cones of the drivers. As the sound wavelength gets similar in size to, or smaller than the diameter of a driver, the sound gets projected in a progressively narrower pattern. Instead of broadly projecting sound, the driver beams it.

For example, look at the manufacturers for the woofers used in that DIY design, the SEAS ER18RNX https://www.madisoundspeakerstore.com/seas-woofers-6-7/seas-prestige-er18rnx-h1456-7-reed-paper-cone-woofer/

They show 3 frequency response curves, one measured directly in front of the driver, on-axis, and off-axis at 30° and 60° angles. Notice that as the frequency increases, those off-axis curves drop at lower frequencies than the on-axis curve. Importantly, the 30° off-axis performance is similar to the on-axis performance as high as roughly 2 kHz. Above 3 kHz, it drops by more than 3 dB, a noticeable drop. The conclusion is that these 6½” (18 cm) woofers can produce good mid range as high as 2 to 2½ kHz. Fortunately it is not difficult to find tweeters that can perform that low without distorting.

In general, as the diameter of a woofer gets larger, the less it can perform in the range where you can directly cross over to a tweeter. Those Advent speakers you recall, with an 8” woofer and an early design dome tweeter, are a good example of how 2-way speakers with too large a woofer, fail in the midrange. Those 8” drivers can produce decent sounding midrange if you listen directly on-axis. But off-axis that midrange falls off enough to make those speakers sound like there is a hole in the mid range. They were limited in how well they could create a good stereo image.

By today’s standards, you will find many good quality 2-way speakers with one or two woofers roughly 5” to 7” in diameter. Larger woofers almost always require a mid range driver. Fortunately, the woofers in that DIY design, mounted in the cabinet described in that DIY link, can produce bass with an F3 (the -3 dB point) of 35 Hz, and useful bass as low as roughly 31 Hz. For most music that works without a subwoofer.

Another excellent post. This information is what I am also looking for. Thank you.

 

[everettT]

I had asked if anyone had heard these in a thread, didn't receive any comments. Based on specs this seems to a great diy design
https://www.madisoundspeakerstore.com/full-range-speaker-kits/halcyon-markaudio-sb-acoustics-full-range-with-bass-assist-tower-pair/

 

[highfigh]

I keep hearing mention of the requirement for the sound of a speaker replicating a live performance, as if the musicians were in the room. What about the other end of that spectrum, where some listeners actually prefer the end result of studio recordings? That in spite of such altered efforts not being exactly genuine, still, there is a quality to it that many people find enjoyable, even if they don't know that's what they like about it.

Secondly, what about the "presence" associated (is this something of my imagination?) with larger woofers and cabinets, in spite of some of the scientifically measured ideals with actual sound projection. For instance, the JBL speakers I own are technically way too large for my space and even though they are called "floor speakers", I have them up on end tables in the corners of the room to clear the sofas. But still, their presence ends up overcoming my environment and lack of ideal acoustical treatments within my space. I am 8 feet away from the speakers that are using my sofa and loveseat as whatever damping they provide, with me positioned in my chair as the final acoustic treatment. My new speakers would also ideally sit atop these end tables. They are safer from the grandchildren there as well.

BTW, I don't mind being told I have this all wrong and that's why I am here. If I'm missing out, I am all for improvement. But there's a limit to how much someone like me may want to know. Is kind of like building a hot rod. Where you take a normal car, rebuild the engine towards performance and make it faster, which it ultimately is, but as you get used to the new found performance, you find yourself wishing you had gone for the stage 3 kit instead of the two. Next thing you know, you're shopping for a Corvette.

Expecting a studio or live recording to sound like the other is futile unless many specific details are used. If a live recording is going to sound like they were in a studio, nothing can be recorded with a mic in open air because mics used for one instrument would pick up sound leakage from other instruments and once that's on the recording, it's not going away. The only way to prevent this is to use isolation boxes for guitars and transducers instead of microphones for others- those almost never sound as good as a mic. Bass and keyboards would be connected directly, without any mics. That said, the bass frequencies can't be stopped from entering any mics used because they pressurize the air. Making a studio recording sound live is often equal to making it sound worse because live recordings A)* don't do well capturing the sound from the listener's POV, B) the sense of space isn't achievable without multiple speakers and C) the sound from a studio recording is more noise-free, meaning ambient sounds don't usually exist. It's hard to add just the right 'noises' that might make a studio recording sound truly live.

*- Many fine live recordings have been made, in all kinds of situations and of all kinds of music. It can be, and has been, done. It's difficult to experience it in a place where it wasn't recorded, though.

Depending on the type of music, it may be almost impossible to replicate a live show because the speakers used for listening at home just don't move as much air and the system isn't powerful enough. It can be very loud, but it's not the same.

 

[TLS Guy]

I keep hearing mention of the requirement for the sound of a speaker replicating a live performance, as if the musicians were in the room. What about the other end of that spectrum, where some listeners actually prefer the end result of studio recordings? That in spite of such altered efforts not being exactly genuine, still, there is a quality to it that many people find enjoyable, even if they don't know that's what they like about it.

Secondly, what about the "presence" associated (is this something of my imagination?) with larger woofers and cabinets, in spite of some of the scientifically measured ideals with actual sound projection. For instance, the JBL speakers I own are technically way too large for my space and even though they are called "floor speakers", I have them up on end tables in the corners of the room to clear the sofas. But still, their presence ends up overcoming my environment and lack of ideal acoustical treatments within my space. I am 8 feet away from the speakers that are using my sofa and loveseat as whatever damping they provide, with me positioned in my chair as the final acoustic treatment. My new speakers would also ideally sit atop these end tables. They are safer from the grandchildren there as well.

BTW, I don't mind being told I have this all wrong and that's why I am here. If I'm missing out, I am all for improvement. But there's a limit to how much someone like me may want to know. Is kind of like building a hot rod. Where you take a normal car, rebuild the engine towards performance and make it faster, which it ultimately is, but as you get used to the new found performance, you find yourself wishing you had gone for the stage 3 kit instead of the two. Next thing you know, you're shopping for a Corvette.

Obviously a studio recording with isolated microphones has no point of reference when played back.

I do not listen to pop or rock or recordings of that nature. I only listen to recordings made in concert hall or church/cathedral spaces. So I need a system that can deliver playback as close to the original sound as possible in a home environment.

So I think you have older JBL speakers and are used to the old "East Coast Sound". That has had its vogue among pop music fans.

Your new speakers will likely not sound anything like those speakers. When you do set them up the tweeters should ideally be 36" above the floor. This is why speakers are a problem as many listeners do not want accurate speakers. For listeners like me the mantra of Peter Walker which was "The closest approach to the original sound" applies.

I'm pretty sure I would strongly dislike your speakers. This is the whole problem of the speaker market.

 

[Swerd]

I keep hearing mention of the requirement for the sound of a speaker replicating a live performance, as if the musicians were in the room. What about the other end of that spectrum, where some listeners actually prefer the end result of studio recordings? That in spite of such altered efforts not being exactly genuine, still, there is a quality to it that many people find enjoyable, even if they don't know that's what they like about it.

I mentioned this mainly because it is something we can control in DIY speaker building. I used the words:

"In home audio, widely radiated sound is a major factor in creating a natural sound. With two speakers operating in stereo, this can create a realistic sounding image of musicians who seem to emerge from the speaker cabinets and sound as if they are within the room."​

to describe an illusion I (and others) can perceive with stereo playback. I emphasize the word illusion, it isn't real. It's the difference between music sounding as if it were played by little tiny musicians sitting inside the speaker cabinets, or musicians who emerged from those boxes and appear to sit within your room.

I do find if the crossover frequencies are carefully chosen, it is a illusion I like. I find it makes a big difference if the drivers (woofers in a 2-way or mids in a 3-way) generating the all-important mid range sound don't beam.

Secondly, what about the "presence" associated (is this something of my imagination?) with larger woofers and cabinets, in spite of some of the scientifically measured ideals with actual sound projection. For instance, the JBL speakers I own are technically way too large for my space and even though they are called "floor speakers", I have them up on end tables in the corners of the room to clear the sofas. But still, their presence ends up overcoming my environment and lack of ideal acoustical treatments within my space. I am 8 feet away from the speakers that are using my sofa and loveseat as whatever damping they provide, with me positioned in my chair as the final acoustic treatment. My new speakers would also ideally sit atop these end tables. They are safer from the grandchildren there as well.

Most of those older designs with large woofers often do sound better (for several reasons) if they are raised above the floor. At an earlier time, I had JBL L-100 3-way speakers with large 12" woofers.

Now I have narrower but taller 2-way towers (MTM design) with two 6" mid woofers, Salk Veracity ST speakers. They certainly do the mid range better, and surprisingly, they also do bass better.

BTW, I don't mind being told I have this all wrong and that's why I am here. If I'm missing out, I am all for improvement…

We do get that, and that's why I and others, such as TLS Guy, like answering you .

 

[MrBoat]

These are the ones I have now.

 

[MrBoat]

I am now considering how I can incorporate a sub into my situation. Even if it means it becomes separately a part of my component shelf system. While although, optimum room placement might not be ideal, perhaps rear, side, or down firing may provide some options.

 

[TLS Guy]

I am now considering how I can incorporate a sub into my situation. Even if it means it becomes separately a part of my component shelf system. While although, optimum room placement might not be ideal, perhaps rear, side, or down firing may provide some options.

What is it you don't like about the speakers you have? Those speakers have an f3 of 32 Hz, so unless you are watching a movie with lots of LFE sound effects, a sub will not add much.

 

[MrBoat]

What is it you don't like about the speakers you have? Those speakers have an f3 of 32 Hz, so unless you are watching a movie with lots of LFE sound effects, a sub will not add much.

No, these speakers definitely don't need a sub. They really don't need much of anything and I don't really have any complaints with them.

I have a couple of other receivers, one of which is the Denon 3805 my friend gave to me which looks like it's never been used with not a scratch on it. He quit using it when he upgraded to HDMI receiver (if I remember what he told me correctly) and has had it stored in it's original box since.

The amp I have hooked to the JBL's is a late 80's, 150w, HH Scott amp of questionable quality. It's a beast. A friend has suggested I change out the spring clip wire terminals with binding posts for a better connection that the JBL's deserve, if nothing else. Still, it's ancient.

I'm just interested in getting current with audio and the improvements must be notable because the speakers and equipment look entirely different than where I came from with it. It would not be a bad thing to have multiple systems to play with and maybe I can learn something new.

DIY interests me because I have likely built at least half of what amounts to my prized possessions. Building things is my day job as well.


ETA: The sub consideration would be for more modern speakers.