A
Little Background on Me and Lowther Drivers
My
favorite audio writer by far is Art Dudley. I often
still think about, and miss Listener
magazine. It was he who whet my appetite to hear
some Lowther-based speakers. That sounds easier than
it is.
At
the time I started to read Listener, I lived
in Columbus, Georgia and couldn't find anyone who
owned a pair. I knew of no dealers, and there are
still very few dealers who stock Lowther-based
speaker systems. I have never been into DIY stuff
much, because I could really botch kits rated “very
easy” to assemble. This seemed to be a downside if
you wanted to learn about Lowthers. So finally, I
broke down and went to a Stereophile show and
set out to find the rooms with speakers that used
Lowther drivers. I loved the sound, but the cabinets
were huge and I could just hear what my wife would
say about them.
I
share all this because when I started reviewing, the
first thing I asked for was Lowther-based speakers.
I thought I would never get them, but this is my
third pair to review in the last six months, and I
have enjoyed them all. The other point of interest
to me is that it seems Art Dudley was very much
influenced early on as an audiophile by Lowthers and
didn't come to personally own Quad 57 ESLs until
2006. My audiophile path is almost just the
opposite. I cut my teeth on the Quad 57s, and still
in my mind’s eye I judge all other speakers by how
they compare to them. It would be 2007 before I
would have a pair of Lowther drivers pumping music
into my listening room.
Well
enough of that, it's time to talk about Lowther
loudspeakers. You know, someone needs to answer the
question: What has made them continue to be so truly
beguiling to audiophiles for nearly 70 years?
Lowther was able to
combine a low-mass
paper cone that uses a incredibly powerful magnet to
produce a driver that has a voltage sensitivity
around 97dB in free air. Add to that the fact that
they have a sensible impedance curve, and all you
have to do is provide the appropriate cabinet or
horn and you have a speaker that can play very loud
and full ranged with an amp as small as two watts.
Lowther started producing hi-fi amplifiers and
tuners in England in the early 1930s. They came in a
large wooden radio cabinet. What the company quickly
became known for though was the partner speaker. A
Paul Voigt corner speaker. It was an amazing feat
then to get a single, six-inch full-range cone with
the addition of a 'whizzer' to play out past 13kHz.
Lowther did a lot of work on magnets, and after WWII
released the new PM1 driver. It retained the same
performance as the original Voigt but was easier to
manufacture and use. This was an era of real success
for Lowther. By the late 1950s, people began to want
stereo and the search was on in most of the world to
build smaller loudspeakers. Thank goodness, Lowther
has continued to refine and produce their wonderful
drivers to this day.
Now,
their frequency response is not exactly ruler flat.
Surely not what one wanted to see in those graphs
they used to run in Stereo Review and
Audio. There is good news though: the older the
driver the smoother it gets. A new driver will
continue to improve, and a freshly repaired one will
continue to improve for at least three years, or so
says longtime Lowther owners. The longer you listen
to a good pair of Lowthers, the more you will be
drawn into the music itself.
Lowthers are far from perfect though. Over the
years, almost
all the successful attempts at Lowther enclosures
have been horns or pipes of some design. Most all of
these have been rather large, and often not high on
the list of wife-pleasing speakers.
It is
very easy to damage them and very expensive to have
them repaired.
For another thing, the drivers themselves have
certain shortcomings, the likes of which make them
unsuitable for less committed hobbyists.
This
is where the engineers and music lovers at Teresonic
come into the picture.
DESCRIPTION & DESIGN GOALS
First
of all, no one could miss the fact that these
speakers have exceptional and beautiful cabinet
work. Rosewood veneers cover the front, top, and
back while the sides are finished in a high gloss
black, and my pair had a beautiful work of art on
the side panels: An original work of art portraying
Charlie Parker playing his sax. Then, there is layer
upon layer of a lacquer made from a very old
European recipe that is applied to the cabinet, and
then it’s polished beautifully. Everyone that came
by thought they were just beautiful, and if you are
lucky enough to get one of the Jazz Legend series,
you become the proud owner of a one-of-the-kind work
of art. You even get the original art work itself
and certification if you buy a pair of these.
Teresonic speakers, right down to the varnish, look
more like musical instruments than high-end audio
speakers. Mike Zivkovic, CEO and co-founder of
Teresonic, says that the shape, woods, and even the
varnishes are part of the Integrum design.
Mentioning Mike, I would be remiss if I did not
share with you that Teresonic speakers are designed
by good engineers who also have a lifelong love for
music and audio. You only have to be with Mike for a
little while to know this. He told me that through
research and trial and error, they have come to
believe that speaker cabinets should be built like
musical instruments. They do not believe that
speaker cabinets should be built as dead and damped
as possible. They feel that a dead cabinet does not
produce a natural and alive sound. That is why their
enclosures are built by fine musical instrument
craftsmen and shaped somewhat like fine musical
instruments.
The
Integrums are so much more than cabinets, they are a
beautiful work of art. They are also a not-so-simple
single-driver, crossover-less speaker. They can use
either the Lowther DX3 that they come with or be
updated to the DX4. The Lowther driver is mounted
in what Teresonic calls an Enhanced Tapered Quarter
Wave Tube (ETQWT). This special transmission line
is a key design priority for Teresonic speakers.
They say this is what enables the extremely clean
and accurate midrange, the widest range of sound
audible to our ears, along with extended low
frequency response.
Most
of us would probably look at them and think they
seem to simply be a Voigt pipe, but there is more in
this design than meets the eye. The sides of the
cabinets are constructed from ľ inch MDF. The front,
rear, and top of the cabinets are curved and thus
are built out of laminated layers of wood that are
built up to also be ľ of an inch thick. There are
internal braces placed to achieve the desired
cabinet resonances.
The
Integrum's quarter-wave pipe is a little over 70"
long, it folds over at the top of the cabinet
instead of curving upward like the top-of-the-line
Teresonic Ingenium. The Integrum's pipe opens to the
front through an 8.5" by 2" rectangular opening near
the bottom of the front cabinet.
Mike
described it to me as both a quarter wave horn and a
transmission line. It definitely has the bass
quality I hear from well-designed transmission
lines. This design gives extended low-frequency
response up to one half-octave below the fundamental
resonance of the Lowther driver. The cabinets also
employ two filled Helmoltz resonators, which are
responsible for correcting the two midrange peaks
that are characteristic of all Lowther driver.
The
sensitivity of the Integrum speaker is stated to be
101.5dB and this seems very reasonable to me. Even
though the manufacturer recommends amplifiers from 3
watts to 100-watt-per-channel, I found they would
play at very loud rock and roll levels with only 2.5
watts. Speakers with this kind of sensitivity open
up a world of dynamics just not available with
low-sensitivity speakers coupled to high-powered
amps.
DESIGNING AROUND THE NATURE OF THE BEAST
As
most of you know, Lowther drivers can be
forward-sounding, or as most often stated, they can
have that “Lowther Shout”.
Teresonic attempts to deal with this with the use of
Helmholtz resonators which are designed for “picking
out” particular frequencies from a complex sound.
The resonators are purely acoustical, and
responsible for the smooth response of Teresonic
speakers without the veiling that notch filters can
cause. These filters are based on the work of Herman
L. F. von Helmholtz from His book, On the
Sensations of Tone, published in 1862. A
Helmholtz resonator is a container of air with an
open neck, or port. A volume of air in and near the
open hole vibrates because of the 'springiness' of
the air inside. A common example is an empty bottle:
the air inside vibrates when you blow across the
top. Teresonic loudspeakers use the Helmholtz
resonators to both smoothen out the 'Lowther Shout'
and to boost the low frequency response. My
understanding from talking with Mike is that there
are two resonators in each Integrum, with a third
inside one of them. My ear tells me this works
incredibly well after the speakers are broken in.
My
pair of drivers came with both the ‘doorknob’ phase
plug (what most people call them this because they
look like a doorknob), and the bullet phase plug.
Each of these phase plugs produce their own unique
sound. To me, the doorknob phase plug helps the
speakers to disappear, but sounds less coherent. The
bullet phase plug is smoother sounding and possibly
a little more detailed. One last way of dealing with
the Lowther shout is in how you position them. I
found they were smoothest when firing almost
straight ahead and towed in very, very slightly.
SPEAKER SETUP & BREAK IN
The
Teresonic Integrums went right into my system. They
were partially broken in, but it still took many,
many hours before they passed the mark of daily
improvement and reached the optimum. Just don't
forget: Lowther drivers take a long, long time to
break in. For most of the time, they were driven by
the Wavac EC300B integrated 300B SET amplifier with
all Western Electric tubes. Later, I will talk
about how they sounded with Teresonic's own custom
built and also special-order 2A3 SET amp. I used
both the Shindo Masseto preamp with its built-in
Shindo step up transformer and the Vacuum State SVP
1 preamp with its active high-gain phono preamp. The
source for vinyl was the Clearaudio Ambient, and
later, their Reference Anniversary turntable both
with their Satisfy tonearm and the wonderful
Micro-Benz TX very-low-output moving-coil cartridge.
I
used the Integrums with Audience, Auditorium 23, and
Teresonic's own speaker cables, the Clarison.
Teresonic's Clarison speaker cables are
copper-stranded wire that is sheathed in an
armor-plated shell to filter out RF and EMI.
Reportedly, this is the same wire and shielding that
is used in fighter jets. It is also the wire that is
used inside the speakers. If I was purchasing
speaker cable, I would get the Teresonic wire, it
seemed to match the best, but I found all three
speaker wires sounded very good with the Integrums.
Like
I mentioned above, at first they sounded best aimed
straight ahead, but over time I towed them in ever
so slightly. They need the supplied spikes to sound
their best, but I recommend you wait and put them on
after you have found their best positioning. I spent
weeks playing with where they sounded best. Some
people have found them best nearer the back wall. I
tried them there; heck I even tried them in the
corners, but in the end they sounded best with the
front of the driver three feet from the back wall
and two feet from the side walls. I found no need
for any special room treatment other then what I use
for all speakers in my room.
SOUND
I want to say right
off the bat that the Teresonic Integrum speakers are
all about extraordinary transparency with incredible
speed at the leading edge. They have dynamics like
you can never get from anything but a horn-loaded
speaker, and voices that are so clear and palpable
that you may think you are there. I'm getting ahead
of myself though, so let me
backup and get started on how they sound, but you
did hear me say they will play seriously loud and
really rock, didn't you?
As I said, I did
most of my listening with the Wavac EC300B
amp, the Shindo Masseto preamp and vinyl. Always
one of the first albums I listen to is Joan Baez's
live recording From Every Stage.
The
recording quality is excellent, with a nice mixture
of instruments to listen to for timbre, there is
also the sound of a live recording to listen to,
then there is that great voice, but most of all it
is just incredible music. The Integrums play this
album as good as I have ever heard. Joan's voice and
the band sounded alive, natural, and just plain
beautiful.
Midrange
The
midrange is where you have to start with these
speakers. As I mentioned above, the Integrums are
extremely transparent,
immediate, dynamic, and alive sounding. Much of this
is from how they get the crucial midrange right. You
can compare them to the Quad ESL 57s, the Ikonoklast
Model 3s, or the Auditorium 23 Solo Vox speakers;
and I think you will come away still thinking the
Integrums are just incredibly realistic and
beautiful in the midrange. I continue to find
speakers with no crossovers to sound so much more
like music. A big reason for this is how they sound
in the midrange.
There are
significant differences in midrange though between
these speakers. The Quad ESL 57 and the Ikonoklast
are both slightly more laid back and maybe a little
more refined-sounding than either of the
single-driver speakers. In contrast, the two
single-driver speakers I mentioned have a raw
aliveness to them that the other two do not have,
and I find it absolutely intoxicating. The Integrums
are beautifully detailed speakers. In this area they
stand up to comparison with great speakers like the
Quad 57s and the unbelievably transparent and
detailed Audio Note Es. The Integrums are very
articulate speakers in the midrange. Voices sound
very alive, very articulate, yet very natural at the
same time. When listening to Alison Krauss, the
Integrum’s ability to recreate the harmony and the
interplay of the voices was just beautiful. Pianos,
like most instruments, benefit from the coherency of
this speaker. They sound powerful and engaging. You
can also very clearly hear both the brushes and the
sticks as they come in contact with cymbals and
drums; they sound so correct and beautiful.
I could go on and
on about the midrange, but let me just say when I
got the Clearaudio Reference Anniversary turntable
and the Benz Ebony TR dialed in with the Integrums,
they sounded more alive than I had ever heard a
stereo sound, and I wasn't the only one to think
this. Mike came over to hear them and he agreed.
What else needs to be said, I just want to listen,
pat my feet, and sometimes just get up and get into
the music. Isn't that all you can hope for from the
midrange of a great speaker?
The Bass
In my review of the
Teresonic Magus I said, “but let's be honest,
Lowther’s don't have a lot of deep bass. I've never
heard a Lowther application that went really deep.”
Well, let me tell
you I have now. The Integrums really do go down to
nearly 30Hz in my room. I can both hear it and
measure it. Let me put it this way, when Warren
Gregoire, the designer of my WGA Ikonoklast
speakers, visited me during the time I was listening
to the Integrums, the first thing he said as he just
walked in the room while the Integrums were playing
was, “they really play deep don't they.” Incredible
midrange is what you expect from Lowther-based
speakers, but not deep, powerful, well defined bass
like this.
The bass doesn't
just go low; it is quick, tight, and really carries
the bass line in the music. Just listen to David
Holland's bass on “Sauerkraut 'n Solar Energy', it's
so lifelike on this setup that I get a lot of quick
glances in my direction when I play it for people.
It has speed, power, and attack that will blow your
mind, but that's not the point. You can follow the
musical line so much better than with most speakers,
and if you have been listening to digital and boxed
speakers, you won't even believe this kind of bass
is possible outside of the live event. As I listened
to recording after recording on the Integrums, I
realized I had never heard a speaker that produces a
more realistic-sounding standup bass. As I tried to
figure out why this was, I came up with three
conclusions; first, the speed of the Integrums
combined with how deep they go; their incredible way
of placing the standup bass in its own space; and
last, their transparency allows it to sound so
lifelike.
Drums sounded
equally good. It didn't matter whether we were
listening to jazz, rock, or classical, the tympani
and drums sounded lifelike. They also had lifelike
dynamics, something you seldom get. They do roll off
fast below 30Hz, but I did not find this to detract
from their musical sound. I would never think of
putting a sub with them, but I know those who would.
I just got out Elvis is Back on vinyl and
played it. No, they don't go as deep as the big
Wilson's do when they demo with this music and
hugely powerful amps; and no they don't rattle the
room like the Wilson's. What they do is play just as
low using a 2.5 watt amp and have a much more
naturalness to the bass. The attack on the drums is
quicker and more startling. The difference between
the power with which the drums is struck, the early
part of the song and the ending climax is much more
apparent with the Integrums. I know this is the
section on the bass, but I must mention that the
real difference is in the voice. If you have not
heard this Elvis recording on the Integrums, the
Solovoxes, or the Shindo Latours you can't imagine
how they captured the essence of Elvis' voice on
this recording. I have heard no conventional or
panel speaker that can do justice to his voice on
this record.
If you come to my
house to hear speakers, I'll start you out with Joan
Baez, and move on to Miles, Ray Brown, and most
definitely Ella and Louie. If my oldest son is home,
you'll get Jimi Hendrix, the Doors, and the Beatles.
Then, if you were over at Mikes house, you would
hear mostly Classical and some choral. It doesn't
matter a bit with the Teresonic Integrums: You will
get bass that sounds like the real thing and goes
plenty deep enough to support and emotionally
involve you in whichever musical performance you are
listening to.
Treble Extension
Just like the
Magus, I never thought about the treble of the
Integrum one way or the other when I was listening
to music, which is the highest compliment I know how
to give a speaker. I say that referring to the
speaker after they broke in. They were bright for
the first few hundred hours, but not in the end; and
I don't think the brightness came from the top-end
anyway. I should not say by comparison that the
treble might not be as airy or as silky as my
Ikonoklast, but I repeat – I only noticed this when
I ask myself to listen for it, not ever when I was
enjoying the music. The speaker has real presence
and has great sparkle. If it misses a little air in
the top, I found it hard to hear. Heck, the midrange
has so much great air and space if they do lack any
in the very top I can't imagine this ever keeping
the speakers from sounding like music.
The real amazing
thing is that you can get this kind of treble from
an 8-inch driver. As I said, I never thought about
the top-end. I sure can't say that about most
speakers I listen to. I'm usually thinking about how
the tweeter integrates with the rest of the system,
or wishing I could tone it down a little, or I'm
blown away by its air and extension. I think part of
the wonder of a single-driver speaker that is well
executed is exactly that. The bass, midrange,
treble, and anything in between all are cut from the
same cloth, so you don't notice the separate parts
of the frequency spectrum, and you are free to just
listen to the music.
Let me make the
point about the top-end one last time. When
listening to Opus 3's Test Record 1, Depth of
Image, I thought the sound was beautiful. For
example, on cut one, “Tiden Bara Gar”, there was
plenty of sparkle and air. The female vocalist
sounded as if nothing at all was separating her and
her acoustical environment from me. Cut six is an
incredible recording of panpipes, and again I could
hear all the air around them. Cut seven on side B is
a recorder and I have never heard it sound more
natural. I know there is no tweeter, but I find the
top-end just beautiful to listen to.
Soundstage and Imaging
The
Teresonic Integrums and the Lowther America Alerions
are quite a contrast in what different people want
in a reproduced soundstage. The Alerions have the
most spectacular audiophile soundstage I have ever
heard. People, instruments, and even the audience
sometimes have their own acoustical space. This is
true both in side-to-side relationships and
front-to-back ones. It is most beguiling and helps
make up for what the eyes do when we watch and hear
live music. On the other hand, the Teresonic
Integrums “soundstage” much more like a real musical
performance than a high-end audio system. By this I
mean they have a whole, complete soundstage. Just
the opposite from what I just described. You get
what I refer to as a coherent soundstage. The parts
are not separated out, but allowed to be individuals
in part of a whole, musical event. Don't get me
wrong, I know how popular the first type of
soundstaging is, but most of my favorite speakers
(Audio Note, Auditorium 23's Solovoxes, Shindo's
Latours, and the WGA Ikonoklast) do not do this, but
they all give you a wide and deep soundstage that is
rock solid; so do the Integrums.
The
speakers are so alive and immediate sounding that
the questions of imaging and soundstaging just don't
seem to come up when people were listening to them.
The reason I say this is not because they lack in
these areas, but that they do not depend on
soundstage and imaging to sound real. I think often
times soundstaging and imaging compensate for an
unrealistic sound. So the soundstage makes us feel
like at least the images in space are amazing. Let
me ask you, have you ever thought about this at a
live concert? I know some of you have closed your
eyes to see how live music images. I have too, then
it dawned on me the insanity of it. I mean when
you’re at a live event it is more than an auditory
experience, don't rob yourself. The Integrum give us
a very realistic soundstage, but they depend on
their musical sound to trick you into thinking you
are there. Truth is just like I have often said
about my Ikonoklast, they sound as real on a great
mono recording as they do with stereo recordings.
Scale
As I have said many
times before, scale is far more important to me than
soundstage and imaging. The Integrums excel in this
area. They have the ability to have huge scale when
called for and to sound small and precise when they
should. They
have a wonderful way of allowing you to experience a
completely natural sense of scale. No better example
could be had of this than the beautifully recorded
audiophile old faithful, Cantate Domino. The
way the organ surrounds and towers over the choir is
so realistic.
The
micro-dynamics
are what I would
expect from a good execution of a Lowther driver; in
a word, they are world class. Yes, the Integrums
have startling dynamics when the big passages come
along, but it may be the micro-dynamics that make it
really sound so alive. I always listen to Muddy
Waters sing the blues when I am evaluating
micro-dynamics. The Teresonic Integrums will stand
up to any speaker in this regard, be it an
electrostat, a ribbon, or most any other speaker.
The way they are with micro-dynamics allows voices
to sound very articulate and natural at the same
time. It allows plucked strings to sound alive. The
micro-dynamics allow you to hear the fingering of
guitars, and just listen to Ray Brown play the bass.
In my way of thinking, well done micro-dynamics like
what the Integrums have is what allows us to really
obtain PraT.
The Sound of Strings
To me, strings are
a big test for any speaker. The Integrums play
strings with speed, life, and air. Like the Shindo
Cortese amp, they are just incredible on plucked
strings. It didn't matter whether it was a blues
guitar, a standup bass in a jazz group, or a harp,
they all sound so natural and so wonderful. You hear
the leading edge, fast, quick and dynamic.
For example, one of
my favorite recordings is King of the Cellist,
Starker plays Kodaly. This is one of the
most beautiful recordings of a cello I have ever
heard. It can also be insightful to listen to the
cuts that are of the cello and the violin. The
Integrums let all of the emotion of this
performances come through. I find Starker to come
across as quite intense, but full of feelings. When
listening to this recording over the Integrums I
found it very hard to take notes, so involving was
the experience. The cello was warm, beautiful, and
quick. The Integrums, when paired with the Shindo
Masseto and the Wavac EC300B, have that special
ability to exhibited a great sense of breath and
space not only around the instrument, but within the
instrument as well. A lot of the speakers that come
in for review can't pul this off.
They convey this
warmth and life without any bass hangover or
boomieness. The violin sounded just as good as the
cello, very sweet, and never bright or strident. The
violin did seem very intense and even aggressive, as
it should on this piece. The emotions the Integrums
relay, as the bow is slowly pulled across the
strings, are very moving. They allow you to hear
different layers and textures of the tones of the
strings as you hear bow passes over each of them.
AMP #2 COMES TO PLAY & A NEW TURNTABLE SHOWS UP
When I went by to
pick up the Teresonic Integrums for review from Mike
Zivkovic, he asked me to sit down and hear them
first. He wanted me to hear what they sounded like
when correctly set up.
I was shocked by
the sheer volume and scale they were capable of,
driven by just 2.5 watts with his custom made 2a3
amp.
Then,
as I was finishing this review, I had an idea. I
called Mike and ask if he could bring the amp over
and leave it for a while, so I could comment on how
the Integrums sounded with 2.5 watts, as well as the
10 watts I had. So I begin my education about the
sound of 2a3 amps. Not only did I get the new amp to
hear them with, I also got in Clearaudio's
Anniversary Reference Turntable. The addition of
these two into my system made for astounding sound
in the bass.
With either amp,
the Clearaudio Anniversary brought a degree of focus
to the Integrum that was just dead on. With the
Teresonic amp and the Anniversary table, the bass
had incredible power and slam. The difference
between the two amps was interesting enough that I
plan to devote an entire review to the Teresonic 2a3
Reference Amplifier.
The new amp did
nothing, but confirm my opinion about these
wonderful speakers. They are capable of revealing
whatever is fed to them. It did show me they could
sound a little bigger and more powerful in the bass
than I had heard them. Again though, that is the
difference in the amps. What I learned from what the
Teresonic Reference 2a3s in my room did accomplish
(besides all the fun of listening to these great
amps) was to confirm what I heard at Mike's place.
The Integrums can really rock and play very loud
with just 2.5 watts. So for all you flea amp lovers
out there; here is a great speaker for you.
CONCLUSION
These speakers both
met my expectations and surprised me. I expected
transparency, tunefulness, speed, and clarity. I
didn't expect such great bass, and I surely didn't
expect them to go down to near 30Hz. It's not weak
bass either. It’s powerful and tight.
Don't misunderstand
me, these speakers are not mostly about the bass.
No, they do so much more. They will absolutely make
music. The Teresonic Integrums deliver all the
single-driver magic I had hoped for without any of
the limitations of the other single-driver speakers
I have heard.
I didn't want to go
overboard here about how great these speaker are,
but it seems I couldn't help myself. They aren't
perfect, but I do really, really like them. They are
natural sounding speakers that really bring music to
life. If you find musical truth in single-ended
triode amps like I do; speakers like the Teresonics
fulfill a real need. Well I've said enough. Let me
leave you with one thought; the Teresonic Integrums
make beautiful music!
