In German colloquialism, telling someone he has a bird -- Du
hast einen Vogel – means you recognize in him that rare but enviable
spark of minor daftness; of a certain eccentricity; of perhaps even a
little inspired craziness. Delivered in this way, your rib poking comes
across as intended. It’s a good-natured jab rather than an accusation of
loony bin destination.
It’s knowing that your friend enjoys riding through town butt-nekkid on
a bicycle in the predawn hours of winter. It’s commemorating that time you
watched him bribe a cop to waive a speeding ticket. He calmly claimed to be
rushing to your wedding and invited the officer to join the
fictitious party. He actually urged him to use his flashing lights
since good times were probably in full swing by then and why should y’all
How about his mid 90s proposal of starting a loudspeaker company that
would deliver handcrafted goods while using mature well-paid American labor
on US soil? You laughingly turned your friend into the proud owner of more
than just a single bird. He cheerfully insisted that all this could readily
be accomplished - against the established design houses no less that even
then were already subcontracting for cheap labor in the Far East. Of course,
when he finally claimed to be just the right guy to pull all this off, you
probably lost your well-practiced patience. Presumably, you accosted him of
having a whole flock of wild-eyed and chirping feathery friends and
paid no more heed to his ambitious dreams.
Par? No, It Pat.
Know anyone like that?
I do. Talked my way into working for him and
enjoyed every minute of it. His name’s Pat McGinty, and that of his
company Meadowlark Audio. His firm’s stocked to the rafters with very
feathery speaker models that go by names like Kite and Shearwater, Heron and
Kestrel, Nightingale and Petrel. What will he christen his forthcoming
subwoofers, pray tell?
More to the point, do you reckon McGinty has a
bird or two?
Based on sheer case evidence, I would have
definitely said yes many moons ago when I granted his long-term survival
prospects skinny hundred to one odds. After all, speaker manufacturing has
turned into a seriously cutthroat business. As a non-drinker, I’d
even have thrown in a bottle of overpriced Napa Valley Kenwood Estate to
make my point. I still worked in audio retail then and was based out of
Sonoma County. From afar, I watched Pat’s little Kestrel floorstander make
the rounds. It soon incited rave word-of-mouth applause. I felt compelled to
nag my storeowner boss to order a pair so I could hear this upstart for
myself while the going was good. Boss-san ended up carrying the line, too.
It soon became evident that Meadowlark Audio was here to stay. I eventually
moved to San Diego County to become McGinty’s National Sales Manager. Good
thing I didn’t bet earlier. I’d probably picked a lousy wine to
congratulate Pat on overcoming the equally lousy odds of my secretive
contest. You see, it’s now quite a few years later again. Not only is
Meadowlark Audio thriving despite a sluggish economy, it’s growing like
one very pregnant ostrich ready to explode.
Backwards In Time Like An Incoherent
As with any good yarn, ours starts in the crib
when the tooth fairy presented li’l Pat with a gold-plated soldering gun.
Dad was a WWII Navy radar man who thought that the proper age for a
youngster’s first electronics lessons was just about when he turned from a
quadruped rug rat into an upright biped monkey. Pat quips that he designed
his first circuits in kindergarten, with a slide ruler rather than pocket
protector sticking out of his jeans. He soon understood electronics the way
other kids understood soccer – from the inside out, indulging it every
spare moment because of sheer enthusiasm. Growing up in close proximity to
the Big Apple, he raptly attended more Leonard Bernstein concerts at Avery
Fisher hall than he can remember. His was also the perfect age to capture
the Fillmore East in the halcyon days of late 60s Rock’n’Roll.
He moved to Southern California where he
eventually transcended surfing and R’n’R to become a hobbyist
cabinetmaker. In his early 30s, woodworking had turned into a full-blown
career. With hands-on training under the ever-watchful eye of master
craftsman Ian Kirby at the Palomar College, he designed and built
furniture-grade custom cabinets and even a few challenging boats.
By his late 30s, the three predominant forces
in his life began to converge: his firm background in electronics and the
sciences; his by now sharply honed cabinet making skills; and his love of
music. Like a renaissance man born into the wrong century, he began building
speakers on weekends. This turned his garage into the proverbial mad
scientist’s lab from where he cranked out a large number of designs that
included the weird and the wacky, the funny and the purely experimental.
Spreading repute soon had him emerge as the King of the One-Off in
Southern California where he fashioned custom loudspeakers for discerning
audiophiles who had the Jones for something unique and exclusive. Having
delved into the accessible literature on speaker engineering, McGinty
initially espoused the Gospel of the latter-day apostles – steep 4th
order filter topologies wedded to closed and vented box alignments with
vertical baffle boards.
Measurements Sound Imperfect
If You’re Looking At The Wrong Measurements
He chronicled his major turning point as the
arrival of the first Melissa spectrum analyzers. Capable analyzers until
then had been the sole providence of the professionals, priced way out of
reach for even the serious hobbyist. These new Melissa units at $3,000 to
$4,000 leveled the playing field. A euphoric McGinty could now properly
outfit himself to produce speakers with stellar measurements and beat the
world - or have the world beat a path to him. He developed an extensive
analog and digital bench and engineered speakers whose measurements compared
favorably with the very best published in Stereophile at the time.
Still, he couldn’t fail to notice that his
new creations sounded pretty darn nasty – fatiguing and irritating, not
musical. This begged the obvious question: why, despite nearly flawless
measurements, couldn’t he stomach his own offspring?
A secret mentor who had guided our budding
cabinet and now speaker builder through the more overlooked and obscure
corners of applied Physics provided the first clue. A sonic signal is a
transverse wave that can be described entirely in the amplitude and time
domain. Imagine ripples on a pond. By knowing their amplitude (the height of
the waves) and time function (how many peaks arise in a given period), one
can accurately depict this event in its entirety. Frequency response,
McGinty’s prior textbook concern and main focus, really was just a derivative
measurement extrapolated from these two core variables. Henceforth, he was
to regard a speaker’s job as the correct reproducer of time and amplitude
data derived from the preceding amplifier. Getting those right would force
frequency to lock into place. Concentrating on frequency and amplitude
instead as is convention had already proven that time as the senior
denominator did not automatically follow suit.
To implement his new course of action required
implementing 1st order networks that are only casually documented
in the major tomes on speaker design. It also meant physical time alignment
of the drivers. While the latter can be achieved with stepped or sloped
baffles, McGinty decided on the angled option for aesthetic reasons. Between
the two available filter choices – parallel or series – he settled on
parallel circuitry but was quick to point out that phase coherence can be
achieved with either.
To McGinty’s astonishment, careful
implementation of phase and time alignment now produced loudspeakers that consistently
put a smile on his face. They finally did justice to that overworked but
I-know-it-when-I-hear-it musicality term - the ability to emotionally
connect with the music. This is McGinty’s self-professed mission. Even if
all the audiophile checklist traits were to be successfully crossed off
-- soundstage precision, subterranean bass as quick as Sugar Ray Leonard and
as pounding as Joe Frazier, airy treble, seductive midrange, blazing
transients, the works – it’d all amount to naught in the Birdman’s
private black book if the emotional response was absent. Since time domain
fidelity had proven to be the door through which he could meet his muse time
and again, Pat dedicated his new company to the 1st order credo.
In Part II next month, we’ll take a closer look at another
important design philosophy, transmission-line loading, an intrinsic
ingredient to his Meadowlark recipe and incorporated into every single
loudspeaker model he makes. For today, let’s consider phase-and-time
coherence. It could make you smile like Pat or wince in horror. That’ll
depend on your sympathies for and appreciation of the subject matter.
It’s A Toasty Blur
A good initial example for visualizing time
domain fidelity is a four-slice toaster. Let it represent a four-way
speaker, each slice the signal from one of the four drivers. Ideally, all
four perfectly browned slices should pop up from our toaster at the exact
same moment when the alarm rings This would signify the arrival of a
single unified aural event at our ears, just the way it was produced in the
live venue. But unless the speaker/toaster was time-aligned, the slices
instead pop up at different times, and not even in sequence either. What should be
a synchronized wave launch -- of a single signal divided by
the crossover into four parts sent to four separate drivers -- becomes in
fact discombobulated. Rather than arriving at your ear as a composite and
recombinant waveform of four drivers working in concert, “it”
arrives in pieces, the woofers and tweeters like self-absorbed prima donnas
each doing their own thing. What else to call that but “it” since it
certainly is not the original signal? To the further horror of 1st
order proponents, some of these fragments, never mind being tardy, aren’t
even the right pieces. Instead, they’re upside down, out-of-phase
A simple measurement that demonstrates this inchoate effect is called step
response. A speaker is asked to instantaneously go positive, like
hooking up a battery to its terminals. This should cause all drivers
(if wired in-phase) to push out and produce a compression airwave. A
properly engineered coherent speaker will create a measurement that looks
like a step – going from zero to full excursion up in a straight line in
one split millisecond, with the drivers retracting back to zero in a sloping
line because of real world woofer response. Incoherent speakers
without regard for phase and time alignment cannot reproduce this simple
step response. They generate a more complex, jagged and convoluted response
curve. They introduce phase rotations that invert and superimpose parts of
the positive-going signal into the negative domain. They transpose outgoing
compression into retracting rarefaction (those previously dubbed wrong pieces).
They store portions of the event and release it delayed in time (the tardy
late-arrivals). Plainly put, a very simple input signal of a milli-duration
click becomes confused. Instead of being rendered with the precise and
devastating impact of a single bullet, it turns into ricocheting buckshot
salvo scattered in time.
Would it surprise you that one of the claimed audible advantages of time
and phase coherent loudspeakers occurs with percussive transients that are
reproduced without telltale blurring scars? Or that images and their
positioning in the soundstage are more accurate because tones that are
reproduced between multiple drivers (the fundamental in one, certain
harmonics in another) have all their constituent parts timed
coincident and correctly to lock into crisp focus without fuzzy outlines or
unrealistically bloated sizing?
This step response was taken during regular Shearwater QC
and shows perfectly synchronized compression without delays
or transposition into rarefaction (going negative)
This - not particularly bad - step response was taken from
a competing design that claims to be time aligned by virtue
of a stepped baffle but uses a higher-order filter. Note the large
amount of high frequency signal that’s delayed and
inverted (undershooting the center line). What should
have been compression has turned late rarefaction. Some of
the low frequency signal arrives late and inverted as well.
The impulse response measurement
applies a full-frequency click to a speaker to track how it settles.
The ideal impulse response curve spikes up, crosses zero, goes negative (the
driver moved out, then back past its original rest position) and phases out
very rapidly thereafter. This demonstrates how quickly and cleanly a speaker
system comes to rest, i.e. stops to produce sound beyond the actual signal.
Perusing just a handful of past Stereophile review measurements of highly
regarded and expensive speakers will show that most are far from this ideal
impulse response. Instead, many go on ringing far past the actual
The question that any 1st order
proponent would now likely ask of his higher-order colleagues is this: why
do their speakers render such a simple aural event with such complexity -
shouldn’t the output signal reflect the input signal? After all, isn’t
that the precise meaning of High Fidelity – remaining faithful to
the signal without taking liberties?
You might have heard the persistent argument
that while time and phase coherence is admirable in theory, it’s in
practice inaudible and an unnecessarily vexing bother to contend with.
Familiar with this notion, I asked Pat to describe the first rudimentary
test that determines the proper baffle angle of physical time alignment for
an upcoming new Meadowlark model. On a test tone generator, he programs an
infinitely short clicking signal pulse and feeds it to a woofer and tweeter
on a mock baffle board mounted on a horizontally rotating axis. Armed with
his ears, a microphone and an oscilloscope, he assumes position at the far
end of the room, triggers the signal and sends it via the microphone to the
scope. Until he arrives at the correct baffle board slant, his equipment
will register two signals – click, click. It records the tweeter
and woofer signals delayed in time. While the ear/brain can’t discern such
closely spaced sounds as two distinct and separate events, it perceives this
timing discrepancy as blurring. Once adjusted properly, the blurring becomes
a razor-sharp, cleary defined and pronounced “pop” rather than a
“pppopp” (or should that be “poop”?). McGinty claims this is clearly
audible to anyone who’d bother with such an experiment.
He then recalled a long-ago demonstration he
had hosted for an audiophile club meeting. His 1st order
presentation sported a two-way speaker with a tweeter mounted onto a drawer
slide. Via a long skinny stick from the listening position, each participant
could freely alter the physical offset between tweeter and woofer by about
1.5 inches to and fro. Without exception, every single music lover not
only heard the differences but also independently adjusted the tweeter to
the same final position. This proved to everyone present McGinty’s
prior audibility contention. What really were rather minor timing
discrepancies of the treble signal in a misaligned 1st order
two-way versus the rather more obvious broadband midrange errors a
misaligned 3-way would have elicited – these relative subtleties were
cleary and repeatably audible. More importantly, they were discerned and
correctly accounted for by average listeners who weren’t trained to
consciously recognize time domain perturbations as any serious engineer of 1st
order loudspeakers obviously would.
Now Prove It
However, outside such an ingenious
demonstration, real world customers comparing 1st order
loudspeakers against any other types in retail or trade show environments
are always comparing apples to oranges. They are never empowered to isolate
the effects of accurate time alignment between two speakers that in all
other regards are absolutely identical. This lamentable fact gave
rise to the popular notion that time coherence is an unnecessary and
inaudible luxury. This retort simply cannot be disproved in any such
settings. It’s something I imagine must ruffle the feathers of
numerous 1st order designers who have no associations with winged
creatures at all.
After speaking with many music lovers over the
years, I’ve learned that those who have “crossed over” into the camp
of phase and time coherent loudspeakers can never retract. Once their
hearing mechanism has identified the artifacts of time domain disturbances
for whatever reasons, they can never not hear them when present - as
they are by design in any loudspeaker that’s not 1st order.
McGinty is obviously very sensitive to this
aspect. He has trained himself to recognize the higher-order sonic signature
he refers to as ringing. Capacitors and inductors store energy and
release it later – that’s their whole raison d’ętre. Higher-order
designs use a larger number of these devices, hence suffer from pronounced
time-domain smearing. Segments of the signal are spread out in time and
arrive sequentially. That’s plain ringing. McGinty hears it readily on
piano, in the impact of the hammer on the string. What should be a sharp
“clack” attack turns into an extended “boiiiinnnng”. He easily
perceives it in soundstage precision, too, and in what he simply calls
naturalness and musicality. For those not attuned to what he’s listening
for, those are vague terms to be sure. But for those who relate, these
qualities are as plain as day. Jim Thiel, incidentally, pointed to the very
same recognizable time-coherent reproduction traits when I interviewed him
earlier for another publication.
Plucking A Feathered Myth
What caught McGinty’s attention when he
explored his first matured 1st order design were greatly improved
dynamics. Dynamics refers to the linear scaling or tracking of increased
input signal versus output signal. Does doubling the input voltage at the
speaker terminal produce double the output level for all drivers? Do
output levels scale proportionally as input voltages are increased? Is this
balance maintained not only with steady-state signals but transients as
well? When does compression set in?
Pat’s findings aren’t entirely surprising
- simpler systems scale more smoothly than complex ones. Their filter
networks insert less reactive, energy-absorbing components into the signal
path. He pointed out that comparing two identical woofers attached to 1st
and 2nd order filters respectively would prove the dynamic
superiority of the simpler filter in a heartbeat.
Then there’s the prevailing myth that 1st
order designs are inferior snake, ahem power handlers. Power handling in a
bass driver is a combined function of excursion and heat. Maximal excursion
– hitting the physical stops – occurs only at a woofer’s lower
reaches, in the octave of 20-40Hz where the effects of its low pass filter
network aren’t operational. This plainly removes the crossover components
from the power handling equation. Thermal limitations arise from
overheating. The glue holding the voice coil in place melts. Meadowlark
drivers employ glue that liquefies at 800°F. While prolonged excessive
power into a woofer will cause self-destruction, this once again is
unrelated to the circuit’s filter network. Rather, it’s a function of
irresponsibly overriding the effective voice coil’s cooling mechanism.
If all things were equal, a steep order
tweeter would outperform the identical unit in a 1st order
circuit during a loudness abuse contest since a shallow slope treble
transducer extends considerably lower in frequency. But clearly, things
aren’t equal. A 1st order designer could and would never
use the cheaper, narrower bandwidth tweeter his 4th order
colleague could get away with. While the latter must spend extra funds on
additional crossover components, the former will spend those dollars on a
better tweeter that can withstand the extended bandwidth demands of his
preferred network. Such budgetary considerations between both camps tend to
balance out in the end, with the steep-order design perhaps saving a few
dollars overall. By way of case evidence, McGinty can’t recall ever
replacing a single Shearwater Scanspeak tweeter due to power failure. With
literally thousands of Kestrels in the field, tweeter warranty repairs for
his entry-level floorstander are less than a handful, something he
attributes to conservative design and fanatical parts QC.
Prototype of new Kite model in new factory -
1.25" excursion custom woofer, 1000-watt internal amp
with bass contour controls, Scanspeak Revelator midrange
and 9800-series tweeter - bass flat to 20Hz, 90dB sensitivity
for hi/mid module.
At the end of the day, power handling is
determined by how loud a speaker can play before it blows up. Pat
invites disbelievers to compare any of his speakers with higher-order
designs of equivalent specifications. He predicts such folks would notice
the exact same thing with either speaker: beyond a certain threshold of
excessive and prolonged decibel levels, both would blow their woofers.
Having built 4th order speakers for close to 20 years, he knows
what he’s talking about.
The Health Food Connection
At this juncture in my interview, I reflected
on the curious status quo which occasionally forces 1st order
proponents like John Dunlavy, Pat McGinty, Jim Thiel and Richard Vandersteen
into having to defend their engineering approach in the face of stalwart
prevalent opposition. It reminds me of pre industrial revolution
society. They didn’t practice biotech genetic engineering on crops then.
Radiation, homogenization, pasteurization, preservatives, pesticides,
artificial colors and foods with zero nutritional value were still a mere
glimmer in the imagination of future exploitation corporations. Our early
ancestors would have been hard-pressed to conceive of the mere idea
of health foods since this very notion suggests the existence of foods that
are actually bad for your physical health. Who but 21st century
man would even consider calling poisons food?
But many obviously do. This turns those who
embrace vegetarianism, health foods, organic and biodynamic produce into
cranks, fanatics, weirdoes and outsiders. Doesn’t it seem more appropriate
to call consumers of Coca Cola, McDonalds, processed American cheese and pop
tarts to the stand? Aren’t they the very ones needing one rocking
explanation as to why they so blatantly trespass against common sense and
the temples of their own physical shells?
I wonder then. Rather than attacking 1st
order loudspeaker designers for preserving the fragile phase and time
relationships of the music signal as it is passed on from source to
amplifier – and may I add, correctly even by the cheapest CD player
or preamp – shouldn’t it rather be the establishment of non-1st
order practitioners who owe us an explanation for why fidelity to timing
isn’t as important as their reasons for disregarding it? What possibly
could those reasons be?
Practicing good cliffhanger routine, we’ll
bow out of these explosive questions for today to revisit Meadowlark Audio
next month. We’ll explore transmission line loading, talk about Pat’s
recent relocation to Watertown, Upstate New York, his new in-house cabinet
shop and a productive new way to overcome traditional operating constraints.
We’ll also check out forthcoming products like his Heron and Nightingale
center channels, two subwoofers and the Kite, a modestly sized 8-inch 3-way
that can be adjusted to extend to 18Hz at +1dB – and that’s not a
Meadowlark Audio Inc.
800 Starbuck Avenue
Watertown, NY 13601
Voice: (315) 779-8875
Fax: (315) 779-8835
A combination of personal and other issues has postponed my planned
interview with Joe Fratus of Art Audio by a few months – expect it around
May or June.