Climbing The Mountain And Reaching The Summit.
Review By Clive Meakins
here to e-mail reviewer.
This review is in some ways an
update to my August 2006 review of the Bastanis Prometheus mkII (reviewed
here) loudspeaker kit within the Enjoy the Music.com Review
Magazine. The Bastanis Prometheus loudspeakers have not been replaced,
far from it, but they now have a bigger brother. Indeed in Greek mythology
Atlas was the brother of Prometheus and given larger size of Atlas, as in
the mountains, their name seems entirely appropriate.
Bastanis Atlas are 100dB/W/m sensitivity open baffle
loudspeakers for frequencies of 100Hz upwards, bass below 100Hz is
provided by a pair of 150 watt solid-state amplifiers powering a pair of
15 inch bass units in sealed boxes. As with Prometheus you can supply the
wood for the baffles and bass units then assemble the loudspeakers
yourself, you can instead purchase pre-cut wood or fully assembled
loudspeakers. There are full plans on the Bastanis site for you to take to
your local supplier. As I did with Prometheus I went to Rockingham Display
in the UK for my CNC cut 25mm Baltic birch plywood.
In the US, cabinet kits and assembled loudspeakers are
available from Tony Landry at AudioSpecialtiesOfNM.com.
In Europe contact Bastanis directly if you want pre-built woodwork.
If you already have Prometheus (Airforce version) you can
upgrade to Atlas in that you can re-use the two 12-inch widebands (midrange
drivers, 100Hz to 11kHz), Gemini tweeters and bass amplifiers. You could
choose to stick with the 12 inch bass units from Prometheus or you can
upgrade to the 15 inchers of Atlas. The driver complement per channel of
Atlas comprises two 12-inch widebands connected in series, the Gemini
tweeter and a very substantial 15-inch bass unit. The widebands and bass
units sport paper cones, the tweeter runs as a dipole, i.e. no with back,
it fires through a wooden horn supplied with the kit. As the widebands are
wired in series these are 16-Ohm loudspeakers, if you run a tube amp and
it doesn't have a 16-Ohm connection you can safely run these loudspeakers
via an 8-Ohm connection. The loudspeakers will be better matched via a
16-Ohm output transformer tap but when I compared the difference via my
8-Ohm tap I didn't find it particularly significant.
is no need for me to run through the construction of Atlas as I built them
in much the same way as described in the Prometheus review so I refer you
back to the August 2006 article. Whereas with Prometheus I used brush-on
liquid wax to finish the wood, this time I used Danish Oil that gave
better results. I made two modifications to the standard plans:
1) I decided it was unlikely that I would use the bass
units butted up to the open baffles so I used a triangular piece of wood
behind the open baffle to act as a support.
2) The Atlas baffles as standard are 1490mm high, my
listening position is relatively low so I reduced the overall height of
the open baffles to 1360mm take account of this. The tweeter height was
set to my ear level when I am seated in my chair. If you do this make sure
you reduce the baffle height from beneath the lower wideband driver. Do
not reduce the baffle height above the top wideband driver as you will
change upper bass performance.
took me a while to organize the cutting of my wood so as soon as I
received the new drivers I swapped the two new widebands into Prometheus
to break them in. The break-in traumas that I suffered with Prometheus
were barely noticeable now that I was exercising the new widebands with
broken-in tweeters and bass drivers. Of course once I built up the new
baffles and bass boxes I would need to break-in the 15-inch bass drivers.
Atlas require a little more space to breath than
Prometheus, the open baffles need to be around 1m from side and rear
walls. I run the bass units against the rear wall in my set up, I need to
do this as if the bass units are in the same plane as the open baffles a
standing wave is created such that I hear little bass in my listening
position. Having the bass units separated from the open baffles is a real
boon in my room. I suspect that my 18ft x 15ft room with a 7ft 3in ceiling
(5.5m x 4.6m x 2.2m) is just about as small as you can run Atlas in.
Bigger rooms will be accommodated and driven with ease.
As I built the open baffles first I used the twin
wideband Atlas open baffles in conjunction with the 12 inch bass units
from Prometheus as I couldn't wait to hear how the twin 12 inch widebands
per channel would sound compared to Prometheus. Driven from Diyhifisupply LD91 300B SE
here) amplifiers I found a tonally richer sound with a stronger
upper-bass and a massive soundstage, really wide, deep and high. The sound
was bolder, more dynamic, and smoother – especially with CD - and
somehow there was a greater sense of being at a performance.
The 12-inch bass units coped well and for smaller rooms
will be adequate. I then got the 15 inch units running, breaking them in
with a diet of serious bass from the likes of Goldfrapp and Rodrigo y
Gabriela "Stairway to Heaven" – 12 inch version.
at the 15-inch drivers tells you this is a loudspeaker with serious
attitude! 12-inch drivers now look small and as for 6 inch bass/mid
drivers, they are mere toys! Now with the full Atlas loudspeaker system in
action there was extra "depth" with seriously deep and powerful bass
available. Everything seemed to gel; speed, detail, dynamics, power,
scale, atmosphere and tonality.
I've lived with Atlas now for 6 months so I can give
some very considered opinions on their level of performance but first I
should mention some set up details that I found helped optimize the
performance delivered by Atlas.
I was supplied with long interconnect cables (5.5m) and
short loudspeaker cables (2m) so that the power amplifiers could be
positioned by the loudspeakers. I was also provided with Bastanis Epilog
main cables for my power amplifiers. For practical reasons alone this
worked well in my situation as it freed up a lot of room on my equipment
racks, and given the space Atlas need to around them to breathe there is
ample room for the power amplifiers behind them.
There's no question that the Bastanis cabling synergizes
well with Bastanis loudspeakers. The mains cables are rather special
although they are also rather chunky and stiff. I found that bass at first
seemed a tad lower in level but this is because it is cleaner, the notes
are more "described", there being more shape to bass notes.
Mid-range, especially vocals, is more natural and clearer. High
frequencies are cleaner too. The Epilog mains cables certainly make a
I also tried loudspeaker-level versus line-level
connection of the bass units. Along with deciding where you prefer the
power amplifiers to be sited you will need to try these different options
to decide what works best in your situation. What I found was that:
interconnects / short loudspeaker cables brought more resolution to the
connection seemed to resolve more detail even in the mid-range, the
slightly cleaner bass with the line-level connection masked detail less
(my preferred configuration)
The differences of the above changes were not profound
so don't worry if for some reason you need to go a different route or that
you find a different set up works for you.
When using a Transformer Volume Control (TVC)
pre-amplifier I felt the frequency extremes were slightly degraded with
the way I'd configured the system. Keep in mind that my sources were
having to drive 2 power amplifiers per channel and 2 sets of long
interconnects per channel, this is a lot to ask of most sources. I tried
the Burson Audio Buffer (reviewed
here) positioned downstream from the TVC. This buffer is very
transparent and offers a useful 6dB of gain. I found the buffer brought
the sound back to where it should have been. Those with an active
preamplifier should already have good ability to drive long cables. Some
with a TVC may find their sources are pushed to their driving-ability
limits with the way I set up the system.
Atlas are ideal partners for SE tube amplifiers,
although I have no reason to doubt that tubed push-pull, solid-state Class
T or other low powered amplifiers wouldn't be a great match. Be warned
that if there is something not quite right with your system these
loudspeakers will tell you in the same way that looking at a picture with
a stain on it would be distracting. Providing whatever problem exists does
not destroy imaging you may be able to put up with it for a while but in
the end you'll need to make sure you mate these loudspeakers with good
electronics and sources. This does not necessarily mean you have to spend
huge sums on partnering equipment.
Bastanis Atlas loudspeakers are quite simply the best I
My statement above is related to my personal
preferences. There are some who do not care for soundstage and imaging. I
do. I crave atmosphere and emotion. Without question Atlas deliver a
tremendous 3-D image both with CD and vinyl. Add to this bass that can be
delicate or truly thunderous, as required, you also have a totally
believable mid-range plus a top-end of crystal clarity. Dynamics can
scare you half-to-death. These loudspeakers will suit those who value SET
amplifiers – BIGTIME! They have an advantage over horns of having a
total absence of "horn shout". This problem with some horns can be tuned
out of systems but I feel that Atlas provides amazing sounds with fewer
tears and compromises than some other high-efficiency routes.
If there's a downside it is that you need to be able to
accommodate Atlas in your room. They will be fine in medium to large
rooms. As for their final looks, if building these loudspeakers yourself
it's up to you how you finish them, your imagination is the limit.
Before I describe some more of what I've been hearing
with Atlas, I will let you know what four people who have visited me have
said. Each person is well acquainted with hi-fi and live music.
1) "Perfect." What this meant is that music
appeared to be live, not reproduced from a stereo system. There seemed
nothing that could be improved upon; this was a completely realistic
2) "I've never heard anything like it before."
Playing bass heavy techo there is scale and massive impact, huge power;
with jazz it is like being there. "Just incredible."
3) "The best speakers I'd heard to date were the £14,000
Tag McLaren F1 AvanteGarde. Atlas betters the
McLaren's, I must now build a system around Atlas."
4) "The band is in the room, if I close my eyes I'm at a
The comments from my visitors just about say it all. I
should add that going back to a more traditional setup with box
loudspeakers changes the experience totally into one that is clearly a
hi-fi system trying to represent real music. Atlas produce such a 3-D
kaleidoscope of sound that it is hard not to believe there is a band
playing on stage in front of me. There is such immersion in sound that
there are some similarities to listening to high quality headphones. To
make sure the full-sized images form, volume levels need to be wound up a
little, not up to "loud" levels but not too quiet either.
There are some loudspeakers that throw detail at you,
with Atlas detail is not in your face but it is present. There are nooks
and crannies around the soundstage where I found subtle details that I'd
not heard before. Because music happens around you the details are not at
all in your face and due to this, detail comes across very naturally.
If you want small and super precise images you won't
find them here, images are BIG scale, there is space around them but these
are big, believable images. If you have a small room and want a
mini-monitor direct sound listening experience then these loudspeakers won't
be for you. Another word of warning, these loudspeakers don't do casual
listening. You cannot avoid a musical experience when you listen to them.
Forget reading while you listen to background music, it simply doesn't
happen, just as you couldn't read a book at a live music venue. Strangely,
whilst I cannot listen and read at the same time I do find I can sleep.
Talking about live music, I travel to Amsterdam every
now and then, when there I try to visit Bourbon Street Blues Club, Atlas
in my room provide an experience that is comparable to being in the club.
This is not just when playing music recorded live such as Jazz at the
Pawnshop which not surprisingly, comes across with bags of atmosphere,
but also with studio recordings. Sonny Rollins, Saxophone Colossus
and Rollins Plays for Bird along with most other recordings do not
come across as being studio based due to the 3-D space the performance
produces. I do not live solely on a diet of jazz, for example
playing Rodrigo y Gabriela "Stairway to Heaven" exhibits pummeling low
frequencies from those 15 inch woofers, the mid to higher frequencies from
the twin 12 inch widebands also move plenty of air – yes they go loud!
It was interesting comparing 8 watts of 300B SE power
versus 2 watts of 45 SE power. The 45 SE amplifier was slightly more
delicate but not in anyway soft. Given that bass below 100Hz is provided
by two 150-watt solid-state amplifiers, there is a powerful foundation for
both of these tubed SE amplifiers. Some will want to be more purist by
using dipole bass units driven by tube amplifiers but I feel the Bastanis
configuration with active solid-state bass provision is a very sensible
approach. A big test was to find out whether 2 watts would be enough. In
my 18ft x 15ft x 7ft 3in room (5.5m x 4.6m x 2.2m) there was just enough
power to play music at high levels but there was little power to spare.
Unless you particularly want to run at ear damaging levels then in my size
of room 2 Watts is enough, not plenty but enough. Do bear in mind that
rooms with lots of soft furnishings, especially if they are behind the
open baffles, will require a little extra power.
I could reel off examples of music from Coltrane to
Dylan, Alison Krauss to Vivaldi, Bach to Grieg, Led Zeppelin through
Cream, Deep Purple and Pink Floyd, they were all played with brilliance.
Bass, when present, is deep, detailed, textured and tuneful with excellent
timing. Mid-range has strong, almost physical, presence – vocals,
guitars and other instruments hang in space. To focus on how Atlas
performs in detail would be the miss the bigger picture and they do create
a BIG picture! Going back to box loudspeakers is quite a shock, a very
different experience and one which somehow encourages me to listen in a
more technical way rather than focusing on the music.
3-D kaleidoscope of sound that Atlas produce leaves me feeling I have
attended a performance, leaving a sense of euphoria. There is a word that
can be over-used, I'm going to use it but with my sense of British
understatement – Awesome. Attack, decay and inner resolution are
only very slightly off the mark, though I do not have any complaints about
these areas. Small drivers with extremely lightweight moving parts
possibly could do fractionally better but would they do as well overall
– I doubt it! I reiterate, Atlas are the best I've heard. Are they
keepers? You bet!
The Bastanis open baffle speaker design is "outside of the
rules" in many aspects, crossing the borders of conventional speaker design. The complex but in other ways simple technical solutions allow us to take a step ahead in sound quality in combination with low wattage amps. Atlas provides the option to choose between assembled
"ready to play" speakers and diy, the diy option uses identical drivers and technology to the assembled version giving
diy'ers access to a sound they won't find in typical hi-fi stores.
All customers get unlimited factory support for assembly, integration and setup, so it is guaranteed that the speakers
will sound optimal within the possibilities of your room and electronics. This extended support is our proven policy, beside the product-quality, the right combination of partnering equipment and speaker placement greatly enhance satisfaction.
Many thanks to Clive Meakins for his fair review, he takes time to learn a product in-depth and lives with it for a while before he starts writing, this method is
superior over the common quick-checks you find in many magazines and offers very good information for the reader.
Type: Open baffle loudspeaker system with
Tweeter: 1 inch compression, horn loaded, 16
Wideband (midrange): Two 12 inch in open baffle, 100Hz to 11kHz, 16
Weight: 42lbs with 25mm birch ply baffles
Woofer: 15 inch in sealed cabinet
Weight: 80lbs with 25mm birch ply cabinets
Power: 1 watt minimum to 150 watt maximum
Subwoofer amplifiers: 150W, 30Hz to 160Hz crossover,
24dB/octave, 3dB boost at 40Hz, subsonic filter at 25Hz, 24dB/octave
Auto switch-on, line and loudspeaker level inputs, 115V and 230V operation,
phase adjustable 0 to 180 degrees
1,300€ for the Atlas wood kit
3,400€ / $4,590for the Atlas kit (excluding baffles & cabinets)
5,200€ for fully assembled loudspeakers
Am Pfaffenbrunnen 7
Voice: +49 (0) 178-7117925