2-way speaker with best bass

I know all the arguments about how crossovers can screw up loudspeakers, and hence the many inherent advantages of 2-ways over multi-driver designs. But there comes a point where the laws of physics can only be bent so far...

So... what IYO is the 2-way speaker that most successfully plumbs the depths, that provides the best full, but "tight and tuneful", bass, with good pitch definition, without completely messing up the higher registers?

For the moment, let's not worry about how this achievement might affect impedance and sensitivity.
Gemme Tanto V2. No crossover on the woofer and only a single cap on the tweeter, very sweet sounding speaker.
Reference 3A DeCappo has much the same setup with an 8" woofer. Wonderful speaker.
"most successfully plumbs the depths, that provides the best full, but "tight and tuneful", bass, with good pitch definition, without completely messing up the higher registers?"

In your room ... Bass Traps correctly placed could help deliver those qualities your looking for

Don't forget Audio Note AN-E/SPe HE with the new Hemp 8 " driver. Possibly my next move for new two-way for "The Office."
Why not add a couple of small, but very good subwoofers behind the speakers you have now? This give you a three way design, without the internal crossover complexity your trying to stay away from....and, including bass flexibility gains overall.

30hz should be more than fine for music, subs with 10-12 drivers are good for this.

A little off topic maybe?....but thats the way I would fill your needs (if I were you of course :-))

The cone of a loudspeaker "breaks up" well below the frequency where it quits making sound. "Breaks up" means that different parts of the cone vibrate at frequencies that have more to do with the cone's mechanical caracteristics than the music. In other words, noise. This sound is undesirable, and should be eliminated by use of an electrical crossover of one kind or another. Output at the desired music frequencies aproaching breakup also exhibits large dips and spikes, also undesirable.

Some cone drivers are better than others. Exceptionally good ones are called "full range". They experience cone breakup too, but the spurious sound is of a pleasant nature that some people like.
This was meant more in the spirit of a "best of" list, rather than as a consultation regarding a specific system.

Recently I briefly heard a diminutive Sonus Faber speaker (not sure which model) putting out prodigious quantities of bass, driven by a Simaudio I-7 integrated, though ultimately it struck me as tending more to the one-note variety.

BTW, I'm surprised to see no votes yet for the Mani-2. What else are the heavy-hitters in this field?

Bass extension and response depends so much on the listening room size and what's in it. Thick carpeting makes a huge difference over even thinner commercial grade carpet. Drapes and upholstered furniture helps tremendously. A first floor room on a slab (vs say a wooden floor with a basement underneath) is a more difficult environment for bass production. The same two way speaker can sound so fantastic in a smaller room with the right treatments vs even a slightly larger room without the right "bass traps" inside. Adding a 2nd powered subwoofer and bass traps are excellent suggestions.

Having said this, I would say a two way speaker with a mid-range/bass driver in the 7" to 8" diameter area vs the more popular 5" to 6" size will produce more bass ext. The Focal 807V Chorus 2-way speaker for example has a 7" mid-range/bass driver with a low frequency point of 41hz. Just a suggestion.
Usher BE-718 tiny dancer. Excellent bass qualities on this speaker. Check reviews for more details.
The original Large Advent has bass appeal I've never heard bettered. If units sold is a valid measure of most successful, these are da bomb.
The problem of bass is that it requires a large driver and a large box. The
problem with midrange is that you need a small driver to produce this
properly - that is without "beaming". You can get prodigious bass
by adding ports to a small woofer but it won't be musical - mostly one note
bass. To get decent bass you need critical damping. To get decent mids you
need proper dispersion (not beaming) and a dome tweeter would be good for
dispersion but it can't handle the excursion necessary to crossover low
enough to a big woofer.

This is all physics.

Given the constraints - there are several ways to go about it.

1) A large driver with a whizzer cone - the draw back is distortion and a
bumpy frequency response in the mids.
2) A small but very powerful woofer (6 inch) in a sealed box with a large
phase plug or dome to control dispersion better in the mids. (You still won't
get much bass but mids will be better and what bass you get will at least be
3) A large driver for bass and with a single horn for mid and tweeter. This
allows you to
crossover low down so you can avoid beaming from a big woofer. You get
good bass and great mids with a gentle roll off in the highs. All round pretty
good except you now have your crossover in a rather critical range (700 to
900 Hz)

Thats pretty much all folks - only so many ways to skin a cat. You can play
with TL and bass extended ported designs until the cows come home but
IMHO you will never get the "best" bass response that way.
Although to many people "best" may simply mean "prodigious" - in which
case anything is possible.
The Merlin VSM mentioned by Pubul uses active eq to set what is IME the standard for extention/definition from a reasonably neutral, smallish 2 way box. There certainly could be a non eq'd 2 driver, 2 way out there that can match the VSMs, but I definitely haven't heard it.

OTOH, if you want parlor tricks -and can abide more deviation from neutrality - the original Red Rose mini monitor skillfully gooses the midbass to enhance its already impressive low end output (for a tiny box) and generate a better illusion of bass than anything I've heard remotely near it's size.

The Gallo Ref3 series uses 3 drivers in a 2 way configuration (the tweeters run full range) and allow use of a 2nd amp to "co-drive" the woofers on a second pair of voice coils. These may be the champs per your specifications.

Finally, as a technical matter, you could mate a subwoofer(s) to a single driver speaker and meet your description. To give some perspective, I get flat resonse +/_ 3db (relative to 80 db) from 25hz to crossover from a pair of Velodyne SPLR 8" subs run through an SMS -1 cross/analyzer/PEQ. I use a number of different mains, but I haven't yet tried a single driver. I'm also told that the Magnepan MMG wall (which can be stand mounted) and some electrostats also operate without a crossover. This set-up will win hands down!

Actually, I think some (or all) of the M-L hybrids meet my last description.

The line arrays in my system profile are 2-ways and have bass as you described in your original post...
2nd vote for the original Advent. At the original cost of about 130$ (I'll stand for correction on price) it was an absolute bargain.
In my room it was the Proac Response 2.5. They really seemed to pump out the bass. As for tuneful though, that goes to the Revel M-20. Not deep but extremely detailed bass.
Shadorne you didn't mention the transmission line cabinet. Helps to get optimum bass from a small woofer. My Meadowlark Shearwater Hot Rods--a TL design--have great bass for a two-way.
The original poster made no claims that they wanted the best bass regardless of type of system. only that he wanted suggestions for 2 ways that had decent bass.

My recommendation is the zaph audio L18 design. I have built two of them, and both times the bass has amazed me. One of the best sounding two way stand mounts I have heard. A very fun speaker. You can view the design at zaphaudio dot com. On the front page, look for the L18 design.
The other issue with bass (and yes room size and volume levels matter a great deal)is the issue of quality versus quantity. The Merlin VSM has no output below 28HZ, but is +/- 2db 33Hz to 22KHz - trust me that is a lot of bass extension for a two-way. It will not succeed at pushing a lot of air like a 15" woofer, but that would be a pretty lousy way to build a two-way. The VSM will give a lot of realistic, tuneful, and articulate bass like no 2-way I have ever heard. While I love the VSM, I would not go around touting it as a real "full-range" speaker in the ultimate sense, but when you combine its balanced performance and incredible coherency (that you rarely get a 3-way+ approach)I think it is one of the 2-way speakers that should be on anyone's list and for the most part you will be satsified with its bass output. Unfortunately, its list price is proabably going up in price to the $14K range, which may seem like a lot for a smallish two-way, but close your eyes, it is worth every penny.
Check out the Klipsch Epic CF4 for sale on this site. A 2 way speaker but with 2 12" drivers. 102dB efficient, slamming bass.
Twoleftears, I take you are looking for a refined, highly resolved system in addition to bass? That is a speaker that would also qualify as a "best in class" type speaker for overall performance. I also assume your question is regradless of cost to some extent.
Certainly Brobdingnag has the best bass. Lilliput may offer some astute, refined, defined and well behaved speakers but the greatest among them can ne'er be more than a magnified miniature.
Sonus Faber Extrema and Usher BE-718 were the two best 2-way I have owned when come to bass quality and quantity.
Audio Note AN/E's. Various ways to place which results in various bass response. I prefer the paper cones. To my ears more tunefull. The hemp will probably play louder before breaking up.
These discussions of how low a frequency can be reproduced always lack one important detail...How loud? Earphones, with tiny "cones" can reproduce the lowest frequency, but at a volume so low that they need to be on the ear to be heard. Small loudspeakers can likewise deliver excellent LF performance, but not at a reasonable volume, particularly in view of the human ear's roll-off at low frequency. Large cone drivers can deliver LF at a volume which is realistic, and without the extreme distortion-producing cone excursion typical of small-driver systems trying for the lowest octave.
Eldartford - good point - reasonable SPLs in the bass means large woofers -
large woofers are ill suited to producing midrange - this is why a two way
system ends up as a near-field or life style type trade off. They are the most
common speaker on the planet because they are the "minimum"
necessary to get 60 to 12 Khz in a flat response. Since the 80's two ways
have been delivering ever more prodigious bass but this is at the expense of
quality bass and a quality midrange - it has all become boom boom tizz,
IMHO. And, as a consequence, no wonder some people are enamored by the
midrange magic of single driver speakers!

If one is to ignore home lifestyle and other domestic considerations and go all
out for just quality sound then one is forced to consider three way or four
way (three way + sub) designs, IMHO. However, there is no doubt that a two-
way seems likely to remain the most popular speaker on the planet - so the
question on this thread is an interesting one!

Those who suggest that simply adding a sub will fix the bass issues of a two
way are forgetting that this is NOT true for the majority of ported bass
extended two way designs - if you go this route then you ideally want a
sealed box two way speaker that rolls off at 80 HZ and has its design goal on
the midrange quality rather than shock and awe ( a design that is NOT bass
extended with all the inherent phase & distortion issues and the typical mid
bass bump up to give "impression" of deep bass).
I bought the Acapella LaCampanellas for just this reason. Their plasma tweeter is outstanding but using it in speaker above the LaCampanellas makes for a complex crossover. They go deep and can play loud.
If you want to get bass below 60Hz from a two-way, you can get it. You have to choose your speaker carefully -- the Merlin VSM mentioned above and the orphaned Meadowlark Shearwater are examples -- then place it well. Realistic, tuneful, articulate bass, yes sir, and low enough that the wavelength is too long for the room and them low lows wind up in the kitchen. Punch you in the spleen and flutter your shoelaces, no.

Not forgetting to give your speaker good electronics, a good source, good cables... all things that affect bass from any speaker, just like placement. I would mention room treatment but a poor room also will keep a more-than-2-way from giving decent low end output. But the OP knows about all these, and the crossover tradeoff factor, and bla bla bla.

So to answer his question : Merlin VSM and Meadowlark Shearwater Hot Rod IMO, and I'm sure there are others.
Another approach would be speakers with self-powered LF drivers that can be tuned to optimize bass according to placement such as the Zu Definition 2s or the Rhethm Saadhana. Not sure if these would qualify as 2-way, but they are crossoverless.
Another two way that is impressing many on the Klipsch forum is the Jubilee. 2 12" drivers mated to a huge horn. 105dB. My 2 way Epic CF3's drop down into the 20's. If you don't mind a 2 way that weighs over a 100 pounds, that is.

Agreed. Firstly let me say this is an awesome speaker. You are talking prodigious bass in a two way. Extremely impressive. However, do you not notice the "hole" in the midrange - especially around 1 to 3 Khz? For sure this kicks butt in the bass but I am sure you'll agree there has been a trade off to achieve this (mostly unavoidable due to physics).
It is impressive, at least to me--the Shearwater's bass, that is. For a two-way, it's exceptional. Mr. Atkinson is more rolled-off in his praise:

reasonable bass extension

--this from the link you kindly provided, Shadorne.

I can see the dishing in the upper mids from 1K to 5K in Mr. Atkinson's tweeter-axis plot, but like other points he brought up in his test series, it didn't seem to bother the reviewer (Chip Stern). I can't say it bothers me either, perhaps because my as-yet-untreated room is quite lively.

If you'd like to hear for yourself how Pat McGinty managed his tradeoff in the Shearwater design, you're welcome. Drop me a line if you come to Montreal.

Yes I was. I must admit that when it comes to the Merlin VSM though and I
did take a look today - they are exceptionally good - great example of
getting everything right in a two-way - you and Tobias picked out a real
winner there! About as good as can be physically achieved in a two way
design - probably the only limitation will be how loud they can play (you can't
have it all but I am sure these are more than enough for most domestic

So what is the trick - smallish woofer (less beaming) and I think the key is
the tweeter - he gets it down to 2.2 Khz with the crossover - that is hard
work for a tweeter - this probably requires something out of the ordinary
with the tweet. This means you get about as beautiful an off axis response as
you ever see (I looked up the the Stereophile review of the VSM Millenium). A
keeper for sure. Actually the Meadowlark is good too - both designs are
pushing the envelope of what two-ways can achieve.
I've not heard the Shearwater, but I did own the Hot Rod Kestrels and they were very good indeed. I wonder what the designer is up to now; it seems he had a real good way with speaker design.
The Altec Model 19 has very good bass, but it's a tad larger than some of the other two-ways mentioned in this thread.

Yeah, Altec model 19. someone else besides me putting forth 2 ways with big cabs and drivers. Why settle for 6" drivers trying to reach the depths, when the right size ones will do it with ease.
This article may be relevant(I actually posted it on a subwoofer thread too) - it is all about trade-offs and what do you call "better" - is "better" more accuracy (good transients) or is it just copious bass (wow that thing makes lots of bass at LF).

"There thus evolved two camps of woofer design: those with strong magnets, having better transient accuracy but worse LF response, and those with weaker magnets having good LF response but poor transient response. However, the poor transient response of a sealed box with a woofer having a weak magnet pales into insignificance alongside the
wholesale demolition of the waveform that takes place
in reflex, bandpass and transmission line speakers."
I had a pair of those Altec 19's. Wish I had them back. Sold them in the early 80's when I didn't know diddly squat. But, once thing I can say, that even with large drivers in a large cabinet, the bass was not really that 'deep'. Tight/fast absolutely and they produced some fairly high SPL's without overloading my room or distorting. Very impressive I think. I'd love to hear them now with tubes. :-)
If you'd like to hear for yourself how Pat McGinty managed his tradeoff in the Shearwater design, you're welcome. Drop me a line if you come to Montreal.

Thanks! I'm not heading that way anytime soon but I appreciate the offer.
I've said it before and I'll say it again, but take a good look at the SP Technology Timepiece 3.0
Good call, Spenceroo. I forgot about the Timepiece - it definitely belongs in this thread.

11-17-08: Spenceroo
I've said it before and I'll say it again, but take a good look at the SP Technology Timepiece 3.0

Nice but be aware of.......... what are you going to pair them with.
Few amps work really well with SPs. Hungry little buggers. Tube pre also helps.

I've been feeding my 3.0s with a pair of Channel Islands D-200s. I don't have a tube pre (Sim Audio P-5LE), but I have a nice tube CD player and lots of vinyl. Things are sounding great so far.
I haven't read all the posts but maybe the totem mani 2 sigs will do the trick.