1
What's New in QC Version 5.0? Overview - General Features (QC Standard Version)
Windows 10 supported (+ Win 7, 8; last version supporting Win XP)
New version of the QC System:
QC Stand-alone Software – perform measurements with any 3rd audio interface
Multiple level measure added to SPL and SPL+IMP
New limit mode for Rub & Buzz: Relative to average level
New calculation mode of harmonics: IEC61286
New acoustic phase calculation removing delay
Online statistics of yield (overall + individual statistic)
Process control : Nelson, Weco or customized rules
Resizable property pages
Impedance Task:
o 4th
order fitting added (vented box parameters)
o Improved measurement of resistive loads
o Pre-loop adjustable for faster testing
o Measure minimal impedance
Live-Monitoring of microphone signal
Yield Statistics: new user interface
Manual Sweep: live analyzer added incl. waveform, spectrum, signal characteristics
User defined windowing of frequency response
Changing setup without discarding Reference DUTs
Improved version control for external references / absolute limits
Settings & limit import unified and extended, feature added to more modules (SPL, SPL+IMP, IMP,
MSC, EXD, EQA); complete test can be configured from external text file
Simplified calibration process (one operation only)
Simplified management of optional features
Level definition of digital audio devices in dBFS
Online detection of new Golden DUT
Reference data supported from any version ≥ QC2.8
Overview - New & Updated Modules
ALS Air Leak Stethoscope (final release)
EQA Equalization and Alignment (final release)
LST Linear Suspension Test
o Measure large size diaphragms up to 18’’
o Optional microphone (resonator parameter fitting) for improved accuracy and stability
WHAT'S NEW IN QC VERSION 5.0
2
QC Stand-alone Software
A new software-only version of the QC System has
been released for measurement with universal audio
interfaces (sound cards).
The KLIPPEL Production Analyzer (PA) is the recom-
mended standard hardware for performing tests on
audio devices with the KLIPPEL QC software. This
measurement device is dedicated to reliable opera-
tion in a production environment and is part of the
QC Basic or QC Standard set. For testing passive
devices (transducers), the Production Analyzer is
required as it provides voltage and current sensors
for accurate measurement of electrical parameters
(impedance, T/S parameters, large signal parame-
ters).
Figure 1 Example setup for testing an active speak-
er with an external soundcard using the QC soft-
ware
However, some testing applications, such as purely
acoustical or line level tests, do not require the spe-
cific features of the PA. A compact USB audio inter-
face may be preferable, especially for mobile testing
applications such as
installed speaker diagnostics,
measurement in car interior,
on-site quality check of rental equipment
and many more.
The QC 5 Stand-alone Software may be purchased
and operated independently from the PA hardware,
only a USB license dongle is required. Virtually any
audio device which provides an ASIO or Windows
Direct Sound driver may be used as measurement
interface. This software version is dedicated to cost-
efficient testing solutions using 3rd
party audio inter-
faces. The Production Analyzer hardware and im-
pedance based measurements are not supported by
this version of the QC System.
Online Statistics Extended – Control
Rules
Control rules (aka zone rules) are a common tool to
monitor whether a process is under control or not.
These rules evaluate the time course of test results
in so-called control charts, which are based on the
moving average and statistical spread of passed
DUTs (devices under test). Well-known rule sets
such as Nelson or WECO rules are provided by the
QC System, but user defined control rules may be
added as well. The picture below illustrates a control
rule example: the resonance frequency fs shows a
trend of six constantly increasing values.
Figure 2 Illustration of a control chart for resonance
frequency (left); Corresponding summary output of
QC Test (right)
By that, scalar test results of the QC system such as
resonance frequency or voice coil offset (MSC add-
on) can be monitored in the background and
checked for the defined rule set automatically. In
case the condition of at least one rule is fulfilled, it
will be indicated in the result window right next to
the individual and overall test verdict. It is possible
to forward a control rule violation to the GPIO of the
Production Analyzer hardware for automated envi-
ronments.
WHAT'S NEW IN QC VERSION 5.0
3
Impedance Measurement - Vented
Box T/S Model Added
The Thiele/Small linear parameter fitting algorithm
of the QC System has been extended for vented box
systems.
Figure 3 Example for 4th order loudspeaker sys-
tems
The standard Impedance measurement task pro-
vides the impedance magnitude and phase as well as
the Thiele/Small parameters (fs, Qts, …). They are
based on a lumped parameter model of the electro-
dynamic transducer (2nd
order) which is fitted to
agree with the measured data. So far, the model
could only be applied to drivers in free air or mount-
ed in a closed test box. For more complex systems,
only impedance could be tested.
Figure 4 Measured and fitted impedance of a vent-
ed speaker system
To extend the model for more complex systems, two
new modes have been added for impedance fitting.
The mode Driver in Vented Box is based on a 4th
order vented box model and it may be applied to
any system with a single driver mounted in an enclo-
sure containing a vent or a passive radiator. This
ensures correct estimation of driver parameters.
Additionally, two new parameters referring to enclo-
sure parameters are available:
fb – Enclosure resonance frequency
(port/passive radiator)
Qb - Total enclosure Q including all enclosure
and vent losses.
Note that the Motor+Suspension Check (MSC) add-
on for fast large signal parameter testing also sup-
ports 4th
order systems.
Manual Sweep Scope & Live
Monitoring of Mic Signal
The manual sweep sine tone generator is a valuable
tool for manual diagnostics of critical units or prob-
lems in the test setup. This feature has been extend-
ed by a real-time scope and controller function.
Failed DUTs can be analyzed while mounted in a test
jig using the response waveform, spectrum and
signal characteristics (peak, RMS etc.).
Figure 5 Schematic overview of driver test setup
with manual sweep diagnostics and live monitoring
For mouse-free operation, KLIPPEL now provides a
new accessory for the QC System: the Manual Sweep
Controller. This universal 3D controller is connected
to the test PC via USB. It enables the operator to
control the frequency and voltage setting of the
WHAT'S NEW IN QC VERSION 5.0
4
manual sweep continuously in an intuitive way
without any additional mouse operation.
Live monitoring of the measurement signal is anoth-
er brand new feature which is a valuable upgrade for
the manual sweep function. Any measurement per-
formed with the QC System may be monitored in
real time using headphones for subjective acoustical
evaluation. Handling is simple; the captured micro-
phone signal is streamed to the standard audio de-
vice (e.g. internal sound card) of the host PC.
Update of Linear Suspension Test
(LST) Add-on
QC5 comes with an updated version of the LST add-
on module for fast testing of suspension parts (spi-
ders, cones, passive radiators) introducing model-
based parameter fitting.
So far, the LST has used laser displacement meas-
urement only. An additional microphone provides
the transfer function between sound pressure and
displacement. This is the base for a resonator pa-
rameter fitting algorithm providing more accurate
results and improved robustness. The technology
has been adapted from SPM Lite module of the
KLIPPEL R&D System.
Figure 6 Principle of LST two signal method
A major benefit of the new measurement technique
is the measurement of parts with a large surface. For
this reason, the SPM Bench has faced an update as
well in order to meet the QC requirements (fast,
upright mounting). Using this equipment, parts with
a diameter of up to 18’’ may be tested.
Figure 7 testing an 18'' cone on the SPM Bench with
QC LST
Import of Setup Parameters and
Limits
Since QC version 4, selected test settings and limits
may be imported from a plain text file. In QC5 this
infrastructure has been generalized to allow com-
plete test setup and limit configuration from exter-
nal files.
Figure 8 Test configuration using text file settings
import
This general settings import may be used for differ-
ent applications such as:
WHAT'S NEW IN QC VERSION 5.0
5
Applying local settings that are specific for a
certain test station (e.g. equalization data for
frequency response)
Exchanging settings between tasks (e.g. online
equalization of reference sound source)
Automated test configuration using external
framework software
Accelerate test setup for repeated settings
(similar tests or multi-channels tests)
and many more.
The simple file format is fully compatible to the
settings log files which are generated automatically
by the QC system for traceability. Therefore, it is
possible to backup and restore setup modifications
easily.
Relaxed Coupling of Setup and
Reference DUTs
By default, the measured reference data for limit
calculation is tightly connected to the measurement
setup, ensuring reasonable and traceable test limits.
This coupling is designated as Reference DUT Integri-
ty. Once reference DUTs are recorded, the meas-
urement setup is protected from modification. How-
ever, display parameters and other non-
measurement relevant settings (e.g. digital in- and
output) can always be modified.
Special applications may require modifying the setup
without any consequences for reference DUTs. Typi-
cal applications are
Use of absolute limits
Use of floating limits
Setup independent limits.
For those cases the tight coupling can be relaxed. As
a consequence, most parameters may be modified
freely, without discarding reference units or limits.
Existing limits are automatically adjusted in case
frequency range and resolution have changed (for-
mat changes).
Windowing of Impulse Response
Impulse response windowing is a common approach
to suppress room reflections (at higher frequencies)
for testing audio systems in a room without anecho-
ic treatment.
Figure 9 Comparison of impulse and frequency
response with and without windowing
This feature has been added to the QC standard
tasks Sound Pressure and combined SPL+IMP. The
window type, length and automatic delay alignment
may be controlled by the user.
Rub&Buzz Testing Relative to
Average Level
A new relative limit calculation mode has been in-
troduced for Rub&Buzz distortion.
Defining testing limits relative to approved reference
units is a common approach in end-of-line testing.
Result deviation caused by the test environment can
be handled by simply shifting the reference average
(or overall max) by a certain tolerance.
Setting reasonable limits can be challenging, espe-
cially for Rub&Buzz distortion (irregular defects,
black solid curve). Comparing the SPL of the distor-
WHAT'S NEW IN QC VERSION 5.0
6
tion relative to the fundamental (main signal) is a
simple but effective approach to evaluate severity of
defect distortion.
Figure 10 Result plot illustrating Rub&Buzz limit
definition relative to the average level of the fre-
quency response
A new limit calculation mode allows defining the
Rub&Buzz testing limit relative to the average level
of the frequency response (reference pool). In com-
bination with the normal shift algorithm, this can be
used as a floor option to prevent the limit from fall-
ing below a defined relative threshold. This improves
robustness for false rejects.