[Vapor Audio]

I'm a speaker guy (but not obsessed by it like some) and as QE knows I tried loving the low wattage approach for years.  Have always liked the simplicity and smallness.  I've heard the low level dynamics, etc. that have been expressed above and wholeheartedly agree with those observations.  But I've yet to find the requisite high efficiency speakers that don't exhibit excessive colorations (I suppose all transducers are bound to have some distortions).  And nearly all high efficiency speakers lack deep bass, which isn't high-end audio in my book. 

That was years ago.  Are there now any low-colored, high efficiency (say 95 dB/w/m), full range (F3 of at least 30 Hz) loudspeakers?

Our Perfect Storm is 94db sensitivity AND efficiency, F3 of 22hz, and as low linear and non-linear distortion as you'll see anywhere.  The downside is as Duke mentioned, physics of such are unbendable, and so the bass cabinet is a nearly 7 cu/ft 10:1 tapering transmission line.  Also flat measuring, ultra-low distortion, high sensitivity drivers are very expensive.  Or in some cases they essentially don't exist, so you have to design and have them built just for your purpose.

[Docere]

Regarding the O.P - do you refer to the musical presentation or technical reasons?

I find it difficult to answer these types of questions - QE and Duke have done a finer job of it than I ever could. My thinking is that speakers and amplifiers form an integrated system. While they can be designed in isolation of each other, the "better" results are achieved when considered together. My experience is limited, but might help someone. Maybe.

Background

Currently in use is my (first DIY build) 2A3 SE amp into GPA 604 type iii drivers running Rick Craig crossovers and loaded in a ~300L MLTL designed by Scott Lindgren. The speaker alignment takes into account the amplifier output impedance and wall-mounting in a small to medium room size. Running test tones, I can hear the bass come in quickly in the mid-20s.

To the point

What makes this system special? I don't know if it is, but it sounds rather different to the lower efficiency systems I have heard. One thing that strikes me is the (relatively) effortless, vibrant, flowing and of-a-whole musical expression. The other thing is that music is less likely to sound overtly "reproduced"... music is just music. I was just listening to Sylvan Esso's album, a largely electronic creation. It was just "musical" sounding... musical in the sense that the humanity of duo came through so very strongly - it was clear to me that the music was well worth making. I was rocking and swinging in my chair with hairs standing. Involving. But, at no point did sonic gremlins trigger a critical or analytical response in me. That was despite a low power amp, running EML meshies (not the most dynamic 2A3 in the stash) having to reproduce some pretty serious bass. There was just music. And me.

Every system is a set of compromises, but I can live with those I have chosen. Coloured? Probably, but there is no getting away from them - you choose the colourations you can live with and avoid those you can't. As an aside, no one has mentioned "horn" colouration when listening to my system. Narrow sweet spot? Not obviously - the directivity is not ideal, but it is much better than many speakers I have listened to. Interestingly, despite some drop off in the highs, the sound is still really enjoyable well outside the sweet spot... or out in the yard. Big? Well, yeah relatively - but I would consider them more mid-size. Still, they can are wall mounted so out of the way, kind of. System noise? Filament hum noticeable with an ear about a foot from the speaker - that's it.

Finale

SETs and efficient speakers designed as a system, have done things I've not heard from other systems... things that are musically important to me. That's in a relatively simple (if large) and not-crazy-expensive system.

Cheers,
Ray

[S1NN3R]

The answer is none. Every system is special. They have their own strength and weakness.

[JLM]

It is interesting to me that the people with the strongest convictions about speakers do not own a low wattage amp.

Seems natural to me if you consider that some are "amp guys" (sensitive to those characteristics and probably electrically minded) and some are "speaker guys" (sensitive to speaker related aspects of reproduced sound).  Each type is more willing to compromise on the other side of the coin.  Note that in the studio, they are most often combined (active speakers) which makes sense to me.

VP - nice but a bit much for my 8ft x 13ft x 21 ft study and (at $27,000) for my retiree budget.

Ray - by your brief description most impressive speaker, would like to know more about it.

[mcgsxr]

I used to run 96dB open baffle speakers with a Magnavox EL84 amp with about 4-5 wpc.

I now run 86dB Maggies with an amp pushing about 500wpc.

Both make excellent music for sure.

[Quiet Earth]

Excellent post Docere. Very well said.

[Freo-1]

Regarding Docere's question: 

The musical presentation is what the thread is primarily supposed to be about.  Low wattage systems have special qualities, mostly with dynamics and life like midrange playback.

[Docere]

No problem explaining the speaker JLM - here goes... I will try to explain by breaking down into component parts, but what is important is how it performs as a system and presents music.

The drivers are the Great Plains Audio 604-8H-iii Duplexes (coaxial). The coaxial helps ensure coherence, especially in a small room where the listening distance might not allow multiple drivers to integrate. The mid-bass driver has a low Qts, which makes for "direct" or resolved sounding speakers; it is also a big" paper cone operating up into the mid-range, which presents some challenges. They are 99dB+ efficient. The tweeter is good quality compression driver operating into a small horn, which makes for a direct sound but also presents some challenges. In summary, the driver can sound direct, coherent and robust; it can also suffer poor power response, a narrow listening position and driver resonances.

Rick Craig (of Selah Audio) designed a unique crossover for these. I asked him to build a crossover that would remove the last hind electronic glare from the drivers without killing their strengths. The crossover is apparently unusual in the crossover point/s and slopes and traps used. Rick's goals were to remove the driver's resonances as best as possible and maintain dispersion.

Scott Lindgren of Woden Audio designed the ~300L MLTL cabinets. They are the Bison design - plans may never have been released commercially. The design took into account the high output impedance of SET amps (as per Duke's explanation); wall loading; and a small to medium room size to achieve a system with balanced bass response. Scott recommended a build in ply (up to 40mm thick in places) and heavy bracing, especially around the areas subject to the most pressure. The drivers are positioned using golden ratio to provide flexibility in positioning and to spread reflections or resonances...

Ben Arends  built the cabinet over here in Australia - he did it for a very reasonable cost. Actually, I doubt he made much if anything on these. They're built form void-free ply wit the crossovers housed in the integrated stands. Nicely finished. About 100kg each... probably a bit excessive for what is a two-way monitor speaker 

The sound? Well, I have described the important aspects in a previous post, so this is "in addition" and will qualify some of my statements. The musical presentation is nicely separated yet seemingly "of a whole". Bands play as a group, but each instrument can be easily isolated and followed. The sound is effortless, robust, tonally saturated and dynamic compared to what is common/popular at the moment. The soundstage is fine and gives an impression of depth, despite the wall loading - images are dense, not sharp-edged cut-outs. The sound is not "boxy" or "honky". The system is also transparent: the differences between source components have been obvious; different component supports sound different and so on. These things are not difficult to hear. Downsides? I am used to slightly lean, small-driver bass and the bass at times seems a little weighty or very slightly under-damped - this is likely a room mode and the result of a lowish loading on my output tube. However, a drummer mate of mine loves the bass response and said it seemed accurate to him. Larger multi-way horns would be more dynamic and direct, but unable to fit in my room and could be less coherent. The aluminum diaphragm compression drivers are not as delicately airy as ribbons or the finest soft or Be domes. They are forthright (but not unruly or overtly aggressive), which could be an issue when matched with unrefined/glaring sources and poor recordings, but can make metal instruments sound real in a way other driver types simply can't. They don't disappear like small two-ways or planars, but sound does not beam from nor coalesce around them either.

Overall, they are old-school, all-rounder musical speakers that have a balance of characteristics I like and nothing that I significantly dislike.

Cheers,
Ray