WOOD CONE MICRO COMPONENT SYSTEM

EX-A15

2009/06/22

EX-A15Product concept　　 Wood Cone system with No.1 Expressive sound

DVD Player•DVD-Audio/Video•HDMI-out with CEC [1080p up conversion]•DIVX standard / JPEG play back•USB Host•USB Music Recording [CD only, MP3, 128kbps, x1]•Vibration suppression mechanism•Independent power supply

RECEIVER•POWER: Wo: 40W x 2 + Tw: 30W x 2•4ch Bi-amp structure•FM (RDS) / AM Tuner•New High-quality sound amplifier “Hybrid Feedback Digital Amplifier”•JVC original “K2 technology” for higher sound quality•2ch mode for connection with other speakers [4Ω/40Wx2]•Vibration suppression mechanism•Independent power supply•iPod option Dock (not include) Ready

SPEAKERS•Sound boards and ribs make significant improvement in expressive base sound •10cm advanced Wood Cone Woofer with “Anisotropic diaphragm” •Maple wood chip absorber makes clearer base sound and higher sound resolution.•Improvement of 10 cm woofer unit. •Improvement of 2cm tweeter unit.•Larger speaker cabinet for richer bass sound [compared with EX-A10]

・ Clear sound

・ Finer “pianissimo” expression

・ Heavier bass sound

・ High resolution bass sound

・ Cloudy sound

・ Difficulty of “pianissimo” expression

・ Lighter bass sound

・ lower resolution of bass sound

Bad effects for sound quality by vibration

Vibration suppression mechanismHybrid insulator, Ark base and High gravity disc tray

Hybrid insulator

Brass foot

Ark base

9mm MDF ark base

High gravity disc tray

High rigidity honeycomb constructionSuede finishwith high gravity resin material incl. glass

Minimize the mechanical vibration

and achieve high quality sound

1. Wider bandwidth （ refer fig. 1 ） ❑ EX-A15 ： 80kHz@ -3dB, 4Ω ❑ EX-A3 ： 50kHz@ -3dB, 4Ω

Higher expression for acoustic field including harmonic overtone.

2 ． Decrease distortion rate, improvement of S/N （ refer fig. 2 b ）

less distortion sound by expanding loop gain to higher range.

New Hybrid Digital Feedback Amplifier

0

-2

-4

-6

-8

-10

2

4

-3dB

-10

-8

-6

-4

-2

0

2

4

1000 10000 100000

Nor

mal

ized

Gai

n [d

B]

wider bandwidth

EX-A3

EX-A15

1kHz 10kHz 100kHz

Fig. 1: frequency relativity with gain Frequency

2ch mode function enabled to connect other speakers that customer likes

Wo: 40W + 40W Tw: 30W + 30W

Bi-Amp Bi-Whirling

40W x 2

2ch Mode

Connecting with SP-EXA15 Other SPKs

2ch mode for connectable with other speakers

The specification and quality that when used in 2ch mode is much higher than EX-A10

This construction improves deep bass sound dramatically with enhanced sound field and

large-scale audio reproduction.

Sound boards and ribs

“ “ is fiber direction

① ②

③ ④ ⑤

Five bamboo parts double-decker construction

PATPEND

Internal braces are optimally placed within the enclosure

Graph of the sound pressure on the point of Frequency 7.8kHz

Normal WOODCONE

EX-AR3 （ Japan model)

Anisotropic diaphragmEX-AR3LTD 　（ Japan model))

This graph said anisotropic diaphragm could make sound field wider

Anisotropic diaphragm makes faster horizontal / vertical sound propagation. This creates detailed

resolution and superior sound field.

Anisotropic diaphragm

Thin wooden sheets are attached on the back of the woofer diaphragm

※Wooden sheets is put on front surface of diaphragm of EX-AR3LTD, not on back side.

New wood chip absorber

Wood chip absorber made of maple makes clearer base sound and higher sound resolution.

Wood material

superficial

dimension (m2/g)

EX-A15 Maple 0.61EX-A3 Cherry 0.37

CherryMaple

Frequency (Hz)

Nor

mal

inci

denc

e so

und

abs

orpt

ion

coef

ficie

nt

α

High-tone range impedance tube, sample size Φ29-40mm

Normal incidence sound absorption coefficient

Cherry for EX-A3

Maple for EX-A15

Higher absorption coefficient material “maple” is much better for pure and high resolution sound

We adopted the world’s 1st cherry wood chip absorber for EX-A3 for clear sound and pureness on high-tone range. We will improve the sound

quality by changing the material from cherry to maple For EX-A15

Improvement of 10 cm woofer

Improves on sound field expression

WOOFER SPK cap improvement

Material: BIRCHEX-A10 EX-A15

Material: CHERRY

Direction: vertical Direction: horizontal

Additional 3 acoustic adjustment parts

1. Aluminum short ring

2. Cupper cap 1 & 2 reduces acoustic distortion

considerably

3. Acoustic Wood chip

3 Improves on sound field expression for

vertical direction Fiber direction: vertical

Material improvement

POLYESTER SILKImproves on three-dimensional sound

image and airy expression

Improvement of 2 cm tweeter

EX-A10 EX-A15

Improves sound purity and realistic

voice coil: CCA(Copper Clad Aluminum)This material is easy to solder which have particular sound

voice coil: 6NOFC99.9999 purity 6N OFC voice coil

Acoustic wood chip

Acoustic Wood chip

Improves on sound field expression for

vertical direction

Fiber direction: vertical

Sound Tuning with JVC Studio Engineers

Studio engineers from the Tokyo Aoyama Recording Studio collaborated in the final sound-tuning stage of the Wood Cone systems. Advice and opinions from the sound-creation experts helped to successfully complete the painstaking process of fine tuning aimed to reproduce sound that is as close as possible to what musicians and composers originally intended.

Professional tuned by Victor studio

Thank you