GROUND ZERO GZ-ULTRA-K-165 6.5 Inch Midwoofer Owner’s Manual
- May 15, 2024
- Ground-Zero
Table of Contents
GZ ULTRA K-165
Owner’s Manual
THE DEFINITION OF ULTRA-HIGH-END
Objects designated as high-end are assigned to this category based on the
assumption that they belong to the top segment of a respective product group
and are generally characterized by unusual, exceptional and exclusive features
and a very high manufacturing quality. In our opinion, the concept of real
high-end is defined much more
extensively by experiencing feelings and the resulting impression when
listening to your favourite music using such devices. Therefore, it was the
only, constant and uncompromising goal during the development of the ULTRA
series to achieve that tingling sensation that goes along with the goosebumps
when the ear lets us perceive things that go
beyond the spectrum that can only be recorded with a test microphone. “ul-tra”
beyond the range of limits | beyond the ordinary | beyond the others
REFERENCE ULTRA Series – UtTRA-HIGH-END
After collecting detailed experience in SQ performance and general in-car
audio reproduction for more than 25 years during the development of
loudspeakers, subwoofers and amplifiers for highly demanding customers and
having launched a wide range of car audio products used for sound quality
competitions all over the world, GROUND ZERO had started to take advantage of
all these gathered skills devising a very new and super high-end product line.
For the most sophisticated demands, GROUND ZERO introduces an extraordinary
two-channel amplifier and matching loudspeakers now! REFERENCE ULTRA series
products are developed by highly attentive engineers from England, Sweden and
Germany creating products for the most demanding customers without accepting
any compromise in overall quality and SQ performance.
TERMS OF WARRANTY
Warranty for this product is covered by GROUND ZERO’s regional distribution partners and their terms and conditions. For further information contact your local retailer or regional distributor.
SAFETY INSTRUCTIONS & MANUFACTURER’S DECLARATION
Keep all parts of the content and the packaging away from children and pets to
avoid accidents and the risk of suffocation.
Permanently extreme levels of over 85 dB can lead to irreparable damage to the
hearing. Music systems with high amplifier output power can reach levels of
130 dB or more. Extreme levels can also hinder the perception of important
traffic noises and distract from what is happening on the road. Ground Zero
GmbH and its sales partners expressly assume no responsibility for hearing
damage, physical damage or any damage to property or consequential damage
resulting from improper or careless use or improper installation of its
products. In particular, any claims are forfeited through the use under
competitive conditions. Hereby, Ground Zero GmbH declares that this product
conforms to the rules of the following EU directives (including all applicable
changes): 2011/65 / EU RoHS2 and 2001/95 / EC directive on general product
safety. The full text of the EU declaration of conformity is available at www
.ground-zero-audio.com. Loudspeakers
contain magnetized metals and some valuable raw materials and must not be
disposed of with normal household waste. Please leave defective or no longer
required components to a local recycling facility at the end of their
practical use.
GENERAL SPECIFICATIONS
| Speaker type | 165 mm / 6.5” SQ midwoofer |
|---|---|
| Nominal impedance | 4 ohms |
| Frequency Response | 45 Hz – 5 kHz |
| Basket type | Multipiece machined aluminum |
| Cone material | Carbon-fleece sandwich cone |
| Motor | High-grade Neodymium |
| Voice coil diameter | 34 mm / 1.34” |
| Max. excursion (p2p)- Xmax | 10 mm / 0.39“ |
| Power handling (RMS) | 100 Watts |
| Power handling (max) | 160 Watts |
| Nominal diameter | 165 mm / 6.5” |
| Mounting diameter | 147 mm / 5.79” |
| Mounting depth | 67 mm / 2.64” |
PARAMETERS
| Resonance frequency – fs | 43 Hz |
|---|---|
| Efficiency – SPL | 87 dB |
| DC voice coil resistance – Re | 3.4 ohms |
| Driver´s Q (nonelectrical losses only) – Qms | 5.56 |
| Driver´s Q (at fs) – Qes | 0.56 |
| Total driver´s Q – Qts | 0.51 |
| Air vol. compliant to driver´s suspension – Vas | 20.4 L |
| Moving mass incl. acoustic load – Mms | 15.4 g |
| Product of magnetic flux density – BL | 5.05 N/A |
| Mech. resistance of driver´s suspension – Rms | 0.75 kg/s |
| Compliance of driver´s suspension – Cms | 0.88 mm/N |
| Voice coil inductance – LE | 0.12 mH |
FEATURES
- Ultra-high-end 165 mm / 6.5” midwoofer
- Tightly-tolerated technical parameters
- Lightweight carbon-fleece sandwich cone
- High-excursion linear moving rubber surround
- High-grade neodymium motor
- Vented voice coil former reducing distortion
- Round copper wire voice coil increasing power handling
- Fine-blasted, black anodized GZ-design basket from machined aluminum parts
- Optimized motor and voice coil ventilation
- Airflow-optimized aluminum cast spokes
- Generously dimensioned flexible spider-woven lead wires
- Gold plated terminals
- Documented final technical inspection
- Wooden box packaging / in matching pairs
- GZ ULTRA 165-GRILL protection grills available separately
GZ REFERENCE ULTRA SERIES
GROUND ZERO is using the worldwide accepted KLIPPEL® R&D Analyzer
KA3 measurement system for speaker development during the German in-house
development as well as for QC reporting for the production line at the
factory. The results of LPM and LS] measurements are the basis for evaluating
and verifying further development enabling to offer perfectly working products
in any practical application. Continuous and advanced trainings for
development employees ensure the highest possible qualification. KLIPPEL® is a
registered trademark of KLIPPEL GmbH.
The most sensitive frequency range of human hearing is the midrange spectrum.
In 2-way loudspeaker setups this essential part of the audio signal used to be
covered rather by the midwoofer than by the tweeter. For this reason, the
target of development must be a smooth, but wide band response starting from a
low resonant frequency up to the crossover point where the tweeter takes over.
At the same time high-dynamical performance and consistent audio reproduction
quality at each desired output level are major requirements.
Design follows function. In fact, the design of the ULTRA K-165 midwoofer is
way more than just imposing cosmetics. The unique basket consists of a set of
machined aluminum parts providing maximum stability for the moving parts but
showing no disturbing influences owing to an air-flow optimized shape of the
spokes. Two layers of carbon-fleece, impregnated with a polymeric resin and a
layer of special damping in-between are united under high temperature and
pressure resulting in a high-strength, exceptionally torsional-rigid but
though
extremely lightweight sandwich cone. Together with a powerful high-grade
neodymium motor, that´s the perfect basis for the intended purpose of a
midwoofer driver, sounding and performing unrivaled great.
Not a huge surprise but a great honour, the performance of the GZ ULTRA K-165 and T-30 charmed the members of the EISA, a group of international car audio trade journalists, right from the very first listening sessions that much that there was any doubt about the decision to award these speakers as simply the
“BEST PRODUCT — IN-CAR SPEAKER SYSTEM”
GROUND ZERO products are engineered in Germany
GROUND ZERO – international sponsor of
Ground Zero GmbH | Erlenweg 25 | 85658 Egmating, Germany