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V O L U M E
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I S S U E
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A P R I L
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IN THIS ISSUE
Trends in Microspeakers
Focus
1
FOCUS
By Mike Klasco
Trends in Microspeakers
By Mike Klasco (Menlo Scientific, Ltd.)
ith more than 1.6 billion mobile phones built annually,
each with a microspeaker for the speakerphone and
another for the receiver, this side of the speaker industry
attracts the giants. Top players include AAC, Goertek, Gettop,
ForGrand, Bujon, and Merry Electronics along with others that
share the sizable market—which includes laptops and tablets.
Fast ramp-up, intense pricing, and other tough challenges have
driven the incumbent microspeaker market leader Knowles to
offload its microspeaker business.
I wrote this article while attending Mobile World Congress
(MWC) in Barcelona, Spain, which is the main global event for
smartphones—from the brands and OEM/ODM factories to the
parts vendors, signal processing specialists, and design houses. As
with most events, the most interesting news is found in the back
rooms, the prototypes kept under the table at some display, or
just the industry gossip. However, I will stick to solid information!
The case can be made that we all spend too much screen
time with our smartphones. The range and diversity of features
and functions and apps are mind boggling. But please don’t
forget that at least one of the core functions of the phone is
to talk to each other—ideally with intelligible and aesthetically
pleasing quality. Now with the leading phones priced at $1,000
and more, shouldn’t we expect our smartphones to deliver better
sound? The speakerphone function on most smartphones goes
south at around 750 to 800 Hz, not so impressive when 300 to
3,000 Hz has been considered a marginal standard for telephony
speech for about 100 years. It appears that while we expect
reasonable sound from our soundbars, autosound systems, and
headphones, when we pick up our beloved smartphones, we
leave our expectations behind.
Microspeakers 2019:
Key Vendors for Mobile Electronics
By Nora Wong
8
DIRECTORY
W
12
ACOUSTIC PATENTS
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TEST BENCH
By James Croft
Two New Woofers:
One from SEAS’ New Extreme Line
and the Other from B&C Speakers
By Vance Dickason
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INDUSTRY WATCH
By Vance Dickason
RUSH
Studio quality sound on the go
SOUND
Today’s audiophiles aren’t just discerning; they’re
also mobile. Their #1 take-along? Headphones
that deliver the kind of crystal-clear, distortion-free
sound you can achieve only with genuine beryllium.
That’s right: Truextent
®
acoustic beryllium domes
now come in sizes ideal for headphone design. You’ll
capture accurate, studio-quality sound that rocks
their world — no matter how fast it’s moving.
VOICE COIL
T
HE
T
EAM
PRESIDENT:
CONTROLLER:
EDITOR:
KC Prescott
Chuck Fellows
Vance Dickason
INTERNATIONAL EDITOR:
EDITORIAL COORDINATOR:
GRAPHICS:
ADVERTISING COORDINATOR:
João Martins
Shannon Becker
Grace Chen
Nathaniel Black
S
UPPORTING
C
OMPANIES
ALMA International 2019
ACO Pacific, Inc.
Audiostar Electronics Co., Ltd.
BMS Speakers GmbH
Celestion
Elektrisola, Inc.
FaitalPRO
HEAD acoustics, Inc.
KLIPPEL,GmbH
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21
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32
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17
5
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LaVoce Co., Ltd.
Materion Electrofusion
Menlo Scientific, Ltd.
PanaSound, Ltd.
Solen Electronique, Inc.
Vance Dickason Consulting
Wavecor, Ltd.
YuonYunn Membrance Co., Ltd.
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2
31
21
19
14
15
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NOT A SUPPORTING COMPANY YET?
Contact Peter Wostrel (voicecoil@smmarketing.us, Phone: 978-281-7708, Fax: 978-281-7706)
to reserve space in the next issue of
Voice Coil.
April 2019
ISSN 1521-091X
Voice Coil, (ISSN 1521-091X), The Periodical for the Loudspeaker Industry, is published
monthly by KCK Media Corp., PO Box 417, Chase City, VA 23924 US,
(434) 533-0246, FAX (888) 980-1303.
Head Office:
KCK Media Corp. Phone: (434) 533-0246
PO Box 417 Chase City, VA 23924
Subscriptions:
Subscriptions to Voice Coil are available in print and digital versions. To subscribe, please visit
our website at www.voicecoilmagazine.com and complete a qualification form.
Qualified subscriptions run for one year. Renew on-line at www.voicecoilmagazine.com
Address Changes/Problems: customerservice@circuitcellar.com
Postmaster: Send address changes to Voice Coil Circulation Dept., PO Box 417,
Chase City, VA 23924.
When you qualify, you will receive an e-mail confirming your subscription. The current
issue of each digital Voice Coil will be posted to www.gotomyvcoil.com at the end of the
month. To access, use the link in the e-mail notification, or you can simply log into the
website to view your issue along with the archived issues.
For those overseas, the cost of a printed subscription is $150.00 per year. Please contact
customer service or order your subscription online at www.voicecoilmagazine.com.
US Advertising:
Strategic Media Marketing, Inc.
2 Main St., Gloucester, MA 01930 US
Phone: (978) 281-7708, Fax: (978) 281-7706, e-mail: voicecoil@smmarketing.us
Advertising rates and terms available on request.
E-mail Nathaniel Black with artwork inquiries at: advertising@audioXpress.com.
Editorial Inquiries:
Send all press releases and information to: Voice Coil, KCK Media Corp.
Editorial Dept., PO Box 417, Chase City, VA 23924.
FAX material to: (888) 980-1303 or e-mail: editorial@audioXpress.com
Legal Notice:
Copyright 2019 by KCK Media Corp. All rights reserved.
Quotation from Voice Coil is forbidden without written permission of the publisher.
Printed in the United States
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VOICE COIL
My wife recently spent $1,500 on an iPhone XS (she likes
lots of memory!). This is about the cost of the Devialet
Phantom, which had the best sounding audio in Apple stores
last year (with real bass to 18 Hz). However, my wife’s XS
microspeaker buzzes when pushed hard. Earlier generations
of iPhones were in the $500 range so it would be a reasonable
expectation of not so special audio. But at $1,500, the value
proposition better offer some magic of the “shock and awe”
variety. The “certified genius” and the store manager took a
listen and rendered their judgment that all was well and the
buzzy voice quality was reasonable for a smartphone. That
works until TCL, Huawei, or OPPO Digital comes along with
something closer to “hi-fi” quality and an extra octave of bass
response without the rattles.
Yet, the future is bright and we are in for a step-change
in sound quality from our smartphones. The smartphone
platform is comprised of a system-on-chip or chipset
(SoC), which includes audio codecs, DACs, and power
amplifiers—and actually these are all quite decent. ESS
Technology, Asahi Kasei Microdevices (AKM), Cirrus Logic
(previously Wolfson), NXP Semiconductors, Qualcomm’s
Qualcomm Aqstic, and even commodity vendor Realtek
more than deliver the goods on the circuit performance. The
compromises to “hi-fi” quality are in the protocols used by
the carriers with which your phone is aligned. But now 5G
is coming to both smartphones and the carriers’ cell towers.
In the US, the race is between AT&T, Verizon, and others
for conversion upgrades to 5G. Add to these protocols
of pristine quality (e.g., Fraunhofer’s EVS) and the move
toward Super Wide-Band (SWB, up to 14 kHz response)
and the sound from next generation of smartphones will be
truly impressive.
Achieving
wideband
clean
sound
from
the
microelectromechanical systems (MEMS) mics is mostly a
design effort of the mic port stack-up configuration and acoustic
wind noise suppression techniques so as not to degrade the
mic’s performance. The microspeakers in the smartphone are
going to be the limiting consideration in speakerphone and
stereo audio playback (gaming, movies, music, etc.).
The push to reduce the footprint and depth continues,
but the microspeaker depth (Z-axis) has ratcheted down
to 2.5 mm from 3 mm for smartphones—driven by the
evaporation of the 3.5 mm headphone jack, which had
been the bottleneck. The same product development teams
that are demanding increased efficiency, power handling,
cleaner sound, and extending the bass and top-end
responses are also demanding the lowest possible price.
Several approaches are being used to overcome the
limitations of size, acoustic output, and power handling in
smartphone microspeakers. One path is to overdesign the
speaker to absorb more power while maintaining practical
mechanical excursion limits. Another more productive path
is using DSP to maximally drive the speakers close to the
edge of their safe operating area (SOA) without overdriving
or damaging the speaker. The SOA can be crudely defined
as the power limits, but it is more accurately defined as the
thermal and mechanical limits. If you use advanced DSP to
bring the microspeaker to its limits but not over them, can
BEST TESTING
Experience cutting-edge technology that enables
true-to-reality and comprehensive tests for your
car audio systems.
HEAD acoustics, Inc.
•
info@headacoustics.com
•
www.head-acoustics.com
APRIL 2019
5

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