MTX Audio Thunder4250D, Thunder6500D, Thunder81000D User Manual

AMPLIFIER OWNER’S MANUAL

POWER
AMPLIFIERS

AMPLIFIERS

2

3

• Intelligent Surface Mount Technology

•

Patented PWM MOSFET Switching Power Supply (#5,598,325)

•

Adaptive Class D Technology

•

High Powered Transformer

•

High Powered stacked inductor

• Pure N-Channel Design

•

Doubles power into 2 ohms

•

Real Time Computerized Protection Circuit

•

Color-coded wire harness for speaker-level input installation on Thunder4250D and 6500D

• Smart-Engage™ auto turn on for easy integration with factory head units Thunder4250D and 6500D

•

Acoustically Seamless Turn-on/Turn-off (i.e. no noise)

•

Variable frequency low-pass crossover, 40Hz to 200Hz, 24dB/octave low pass

•

Defeatable compression circuit included on Thunder6500D and Thunder81000D

•

Continuously adjustable and defeatable Bass EQ enhancement circuitry, centered at 40Hz

•

Low level inputs

•

EBC - External Bass Control Port with an additional 3dB of gain when used, and 23dB attenuation

•

Adjustable input sensitivity

•

Buffered RCA Outputs for daisy-chaining additional bass amplifiers

• Nickel-plated, heavy duty terminal block type connectors

• Unique rubber Insulated Iso-Feet™

THUNDER4250D

RMS Power measured at 12.5 Volts DC:
125 Watts x 1 into a 4 Ohm load with less than 1% Thd+N
250 Watts x 1 into a 2 Ohm load with less than 1% Thd+N
Dynamic Power measured at 14.4 Volts DC
200 Watts x 1 into a 4 Ohm load
350 Watts x 1 into a 2 Ohm load
Signal to Noise Ratio: ≥100dB A-Weighted
Damping Factor: >200
Frequency Response: 20Hz-200Hz
Maximum Input: 8Vrms
Thunder EQ: Variable Bass Boost (0-18dB) centered at 40Hz
Crossover: Variable 40Hz to 200Hz, 24dB/octave low pass
Dimensions: 7" x 9.75" x 2" (17.8cm x 24.8cm x 5.1cm)

9.9" x 9.75" x 2.1" (23.6cm x 24.8cm x 5.3cm) Including IsoFeet™

THUNDER6500D

RMS Power measured at 12.5 Volts DC:
250 Watts x 1 into a 4 Ohm load with less than 1% Thd+N
500 Watts x 1 into a 2 Ohm load with less than 1% Thd+N
Dynamic Power measured at 14.4 Volts DC
450 Watts x 1 into a 4 Ohm load
775 Watts x 1 into a 2 Ohm load
Signal to Noise Ratio: ≥100dB A-Weighted
Damping Factor: >200
Frequency Response: 20Hz-200Hz
Maximum Input: 8Vrms
Thunder EQ: Variable Bass Boost (0-18dB) centered at 40Hz
Crossover: Variable 40Hz to 200Hz, 24dB/octave low pass
Dimensions: 11.5" x 9.75" x 2" (29.2cm x 24.8cm x 5.1cm)

13.9" x 9.75" x 2.1" (36.6cm x 24.8cm x 5.3cm) Including IsoFeet™

Features

Specifications

THUNDER81000D

RMS Power measured at 12.5 Volts DC:
500 Watts x 1 into a 4 Ohm load with less than 2% Thd+N
1000 Watts x 1 into a 2 Ohm load with less than 2% Thd+N
Dynamic Power measured at 14.4 Volts DC
850 Watts x 1 into a 4 Ohm load
1500 Watts x 1 into a 2 Ohm load
Signal to Noise Ratio: ≥100dB A-Weighted
Damping Factor: >100
Frequency Response: 20Hz-200Hz
Maximum Input: 8Vrms
Thunder EQ: Variable Bass Boost (0-18dB) centered at 40Hz
Crossover: Variable 40Hz to 200Hz, 24dB/octave low pass
Dimensions:15.4" x 9.75" x 2".(40.1cm x 24.8cm x 5.1cm)

17.8" x 9.75" x 2.1" (45.2cm x 24.8cm x 5.3cm) Including IsoFeet™
Recommended Fuse = 150A

CONGRATULATIONS...

on your purchase of a new MTX Audio
Thunder Amplifier! MTX has long been
the industry leader in mobile enclosures
and speakers, and we have reached
new heights with the development of the
new MTX Thunder amplifiers. You
couldn’t have chosen a more reliable,
powerful, or better performing amplifier.
In fact, we back up every Thunder
amplifier with a three-year warranty if
installed by an authorized MTX Audio
retailer (see the warranty statement.

Your new MTX Thunder amplifier was
designed, built and thoroughly tested at our
state-of-the-art electronics manufacturing
facility in Phoenix, Arizona. We manufacture
every amplifier using the latest Intelligent
Surface Mount Technology. Some of the
advantages of the new design are its signifi­cant improvements to the amplifier’s electrical
and mechanical properties. ISMT devices
feature substantially shorter internal and
external lead lengths. This reduces stray
capacitance and inductance, which results in
cleaner and more accurate musical reproduc­tion with significantly less noise interference.
The ISMT mounter produces amplifier boards
with smaller and lighter components, which
are more resistant to vibrations inherent in the
automotive environment.

A word about power ratings. It is important for you
to know how they stack up. MTX has chosen the
most honest, most conservative way to rate our
amps. We show you the RMS power, at 12.5 volts,
and dynamic power at 14.4 volts. However, we go
above and beyond the call of duty. We test each
amplifier. The technician records the “actual”
power output, and records this number on your
Certified Performance Certificate. The amplifier

must meet or exceed the rated specification
before we’ll ship it. No questions. No exceptions.

We want to ensure you get continuous high
performance from your MTX Thunder
amplifier, so we recommend that you have it
professionally installed by your authorized
MTX dealer.

HOW TO USE THIS MANUAL

If you are installing this amplifier yourself, we
recommend that you read the manual cover­to-cover before you install it. Familiarize
yourself with the features and details on the
input and output panels. Make sure you have
all the equipment you need. Then follow the
step-by-step installation instructions included.
Sample installation diagrams may be found
on our website:

mtx.com

If you have any questions, write or call us:

MTX Audio

4545 E. Baseline Rd. Phoenix, AZ 85042

602-438-4545 • 800-CALL MTX

[e-mail]

mtx.com

Please take a moment to register your

purchase on line at mtx.com.

Please also record the serial number of
your amplifier in the space provided below
and keep this manual for future reference,
as well as your sales receipt as proof of
ownership. (The serial number of your
amplifier is marked on the bottom of its
metal chassis.)

Serial Number:
Date of Purchase:

Introduction

ENGLISH

AMPLIFIERS

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5

1. Gain Controls – These controls are used to match the input sensitivity of the amplifier to the particular
source unit that you are using. The controls are factory set to 1Vrms.

2. Thunder EQ – This equalization circuit is used to enhance the low frequency response of the vehicle’s
interior. With up to 18 dB of boost and centered at 40Hz, the Bass EQ can be adjusted to meet your own
personal taste.

3. Frequency Control – This control is continuously adjustable from 40Hz through 200Hz at 24dB per octave.
Factory setting is at 40Hz.

4. RCA Input Jacks – RCA type input jacks for use with source units that have RCA or Line Level Outputs.
A source unit with a minimum output level of 200mV is required for proper operation. However, this input
will accept levels up to 8Vrms.

5. EBC 2 – The EBC, or Electronic Bass Control, allows a remote bass control to be adjusted from the dri­ver’s seat. If the optional EBC is installed, the bass level will be able to be adjusted to overcome noise and
other interference. With EBC 2 multiple amplifiers can be controlled.

6. RCA-Output Jacks – These RCA outputs allow for a signal to be sent to other amplifiers in a daisy-chain
configuration. The RCA outputs also allow for multiple bass amplifiers to be level controlled using one EBC.

7. Speaker Level Inputs – This input will allow the Thunder4250D and 6500D to operate from source units
with speaker-level outputs. Output speaker leads from the source unit should be tied directly to the wire
harness provided with the amplifier.

Wire harness color codes:
Grey / Black = Source units right negative (-) White / Black = Source units left negative (-)
Solid Grey = Source units right positive (+) Solid White = Source units left positive (+)

With the Smart-Engage™ auto-turn circuit, a remote turn-on wire is not necessary when connecting the
speaker-level input wire harness to a high powered source unit. The amplifier will automatically turn on
when music is received.

8. Compression Circuit – This new circuit, found on the Thunder6500D and Thunder81000D,
prevents the amplifier from going into clipping, even at high SPL levels. The compression circuit allows the
listener to play the amplifier at high volume levels, yet protects the speakers against the potential damage
that can occur during dynamic musical passages. The circuit is switchable on/off, for those SPL competi­tors who run their amplifiers into clipping on purpose. Warning: Damage to speakers may occur when the
compression circuit is in the off position.

Input Panel Layout

❶

❹

❺

❻

❷

❸

❼

❶

❹

❺

❻

❷

❸

❼

❶

❹

❺

❻

❷

❸

❽

❽

AMPLIFIERS

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7

1. Fuses- For convenience, all amplifiers utilize ATC type fuses. For continued protection in the event that a fuse blows,
replace the fuse only with the same value.
Caution - The power fuses on the amp are for protecting the amp against overdrive. To protect the vehicle’s
electrical system, an additional fuse is required within 18" of the battery on the 12V+ cable.

Thunder4250D - 20A x 2
Thunder6500D - 25A x 3
Thunder81000D - 150 Amps (not supplied)

2. Power Terminal – This is the main power input for the amplifier and must be connected direct­ly to the positive terminal of the car battery for the amplifier to operate properly. See the chart
below for recommended cable sizes for each amplifier. Use caution when running this cable
through the car. Try to avoid the input RCA cables, antenna cabling, or other sensitive equipment
as the large amount of current flowing through this cable can induce noise into your system. It is
also very important to have a tight connection to ensure maximum performance.

Thunder4250D – 6-8 Gauge
Thunder6500D – 4-6 Gauge
Thunder81000D – 1/0 Gauge only

3. Ground Terminal – A good quality ground is required for your Thunder Amplifier to operate at
peak performance. A short length of cable the same gauge as your power cable should be used
to attach the ground terminal directly to the chassis of the car. Always scrape or sand any paint­ed surfaces to expose bare metal where the ground wire will attach.

4. Remote Terminal – All Thunder Amplifiers can be turned on by applying 12 volts to this termi­nal. Typically this voltage is supplied by a wire from the source unit marked “remote” or “electric
antenna”.

5. Speaker Terminals – As shown in the wiring diagrams, be sure to observe speaker polarity
through the system. Failing to wire the speakers in proper phase could result in a loss of bass
response and/or poor overall sound quality. Caution: Thunder amplifiers are not recommended for

loads below 2 ohms stereo or 4 ohms bridged.

6. Power LED (top of heatsink)-

A lighted LED indicates that power has been applied to the amplifier. +12V from the
battery to the +BATT terminal (#10) and +12V from a switched ignition or remote lead from a head unit. An
unlighted LED indicates power has been removed or the amplifier has overheated. In the case of the overheat
condition, the amplifier will turn back on after it cools down.

Output Panel Layout

❶

❷

❸

❹

❶

❷

❸

❹

❷

❹

❸

❺

❺

❺

AMPLIFIERS

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9

The following list of terms with their definitions is offered as
help in understanding the set-up and operation of your
amplifier.

1. Crossover (xover) - an electrical filter with high-pass or
low-pass characteristics that divides the frequency range
into playable bands for certain speakers. Subwoofers, mid­bass, midrange and tweeters are all designed to play differ­ent frequencies and should do so to avoid damage. The
xover point is where the playable frequencies cross from
one speaker to the next at -3dB below reference level.

2. Full-range - refers to signals which cover the entire audio
frequency span from 20Hz to 20kHz.

3. High-pass - simply put, this blocks lower frequencies
which damage smaller speakers, and passes the higher
frequencies for smaller speakers like the midrange and
tweeter.

4. Low-pass - you got it, this is the inverse of a high-pass. It
blocks higher frequencies and passes the playable lower
frequencies to the larger speakers, like subwoofers.

5. Impedance - the resistance to the flow of current in an
alternating current circuit (such as with music). Line level
circuits are typically a high impedance of several thousand
ohms, while speaker level circuits are usually a low imped­ance of a few ohms.

6. Line level - the type of signal produced at the outputs of
tape decks, CD tuners, preamplifiers, etc., with a typical
value of a volt or less in a high impedance circuit.

7. Speaker level - the type of output that is meant to drive
speakers. These signals are sometimes called high level
and are usually connected by two conductor speaker wires.

8. Signal - the signal of an audio system is what is heard
from the speakers. These signals may be high pass, low
pass or full-range.

We don’t have enough space for Electronics 101, so if you
have a good, bad or amusing question, please call us TOLL
FREE at 800-CALL MTX! (800-225-5689)

Adjusting the Gain

1. Turn the gain control on the amplifier all the way down.

2. Turn up the volume control on the source unit to

approximately 3/4 of maximum.

3. Adjust the gain control on the amplifier until audible distor-

tion occurs.

4.

Adjust the gain control down until audible distortion dis­appears.

5.

The amplifier is now calibrated to the output of the
source unit.

Typical Speaker

Wiring

Configurations

Definitions of Common Terms

Read this if you wanna be a do-it-yourselfer - or give us a call at 800-CALL MTX.

Problem Cause Solution

No LED indication No +12V at remote connection Supply +12V to terminal

No +12V at Power connection Supply +12V to terminal
Insufficient ground connection Verify ground connection
Blown power fuse Replace fuse

LED on, no output Volume on head unit off Increase volume on head unit

Speaker connections not made Make speaker connections
Gain control on amplifier off Turn up gain
Signal processing units off Apply power to signal processor
All speakers blown Replace speakers

Output distorted Head unit volume set too high Lower head unit volume

Amplifier gain set too high Lower amplifier gain

Balance reversed Speakers wired L + R reversed Wire speakers with correct orientation

RCA inputs reversed Reverse RCA inputs

Some balance reversed Some Speakers wired L + R Wire speakers with correct orientation

reversed
Some RCA inputs reversed Reverse appropriate RCA inputs

Bass is boomy Thunder EQ too high Lower setting

Bass is weak Thunder EQ too low Raise setting

Speakers wired out Wire with correct phase
of phase
Not using MTX woofers Buy MTX woofers

Blowing fuses Excessive output levels Lower volume

Amplifier defective Return for service

Troubleshooting Guide

AMPLIFIERS

10

11

Introduction

FELICITATIONS...

vous félicitant de votre achat d’un nou­veau amplificateur MTX Audio Thunder
! MTX a été depuis longtemps un leader
dans l’industrie d’enclos mobiles et
speakers, et nous sommes arrivés à un
nouveau sommet avec le développe­ment des nouveaux amplificateurs
MTX Thunder. Vous n’auriez pas pu
choisir d’amplificateur plus fiable, plus
puissant ou meilleur - en effet ; nous
garantissons pendant trois ans chaque
amplificateur Thunder s’il est installé
par un vendeur agréé (voir la garantie).

Votre nouvel amplicateur MTX Thunder a été
conçu, construit et testé dans notre usine
électronique de dernier cri à Phoenix,
Arizona. Nous fabriquons chaque amplifica­teur en employant la Technologie Surface
Mount le plus récent et intelligent . Quelques
advantages du nouveau dessin sont les per­fectionnements aux propriétés mécaniques et
électriques de l’amplificateur. Les mécan­ismes ISMT ont de substantiellement plus
courtes longueurs internes et externes. Cela
réduit l’inductance et la capacitance égarées,
qui résulte en une reproduction musicale plus
pure et plus exacte avec considérablement
moins d’intervention du bruit. Le ISMT
mounter produit des cartes d’amplificateur
avec plus petits et plus légèrs composants qui
sont plus résistants aux vibrations inhérentes
dans l’environnement automobile.

Un mot au sujet d’évaluations de puissance.
C’est important de savoir comment elles s’y
comparent. MTX a choisi la méthode la plus
honnête et la plus conservatrice d’estimer les
ampères. Nous vous montrons la puissance
RMS, aux 12,5 volts et la puissance
dynamique aux 14,4 volts. Cependant ; nous
allons au-delà l’appel de devoir. Nous testons
chaque amplificateur. Le technicien enreg

istre la puissance de sortie ‘actuelle’, et puis
il note ce nombre sur votre Certificat de
Performance Attesté. L’amplificateur doit sat­isfaire ou dépasser les spécifications d’évalu­ation avant d’être envoyé. Pas de questions.
Pas d’exceptions.

Nous voulons tout faire pour assurer que vous
obtenez la haute performance continue de
votre amplificateur MTX Thunder, donc nous
vous recommandons de l’avoir installé profes­sionellement par votre vendeur agréé.

COMMENT UTILISER CE MANUEL

Si vous installez cet amplificateur vous­même, nous vous recommandons de lire ce
manuel de la première à la dernière page
avant de l’installer. Familiarisez-vous avec les
caractéristiques et les détails des panneaux
entrée-sortie. Vérifiez que vous avez tout
l’équipement dont vous avez besoin. Puis
suivez les instructions d’installation point par
point qui se trouvent. Vous pouvez trouver
des échantillons des diagrammes d’installa­tion sur le Web à notre site :

mtx.com

Si vous avez des questions, écrivez ou

téléphonez-nous à :

MTX Audio

4545 E. Baseline Rd.

Phoenix, AZ 85042

602-438-4545

800-CALL MTX

[e-mail]

mtx.com

FRANÇAIS

• Technologie Intelligente Surface Mount

• Source d’alimentation à découpage PWM MOSFET brevetée (n° 5 598 325)

• Technologie d’adaptation Classe D

• Transformateur haute puissance

• Inducteur empilé haute puissance

• Dessin N-Canal pur

• Double la puissance sous 2 ohms

• Circuit de protection informatisé temps réel

• Harnais métallique codifié par couleurs pour l’installation d’éntrée au niveau speaker avec Thunder4250D

• Allumage automatique Smart-Engage™ pour une intégration facile aux appareils sortis d’usine

• Marche/arrêt totalement silencieux

• Filtre passe-bas de fréquence variable (40 à 200 Hz), passe-bas de 24dB/octave

• Circuit d’accentuation des basses Bass EQ, réglable en continu ou supprimable, centré sur 40 Hz

• Entrées de basse fréquence

• Circuit de compression defeatable compris avec Thunder6500D et Thunder81000D

• Prise de commande des basses EBC-External fournissant un gain supplémentaire de 3dB et atténuation infinie

• Sensibilité d’entrée réglable

• Sorties RCA tamponnées pour la connexion en guirlande d’amplis de basses supplémentaires

• Bloc de connexions plaqué or ultra-solide

• Connecteurs nickelés, d’un type bloc terminal à usage industriel

• Iso-Feet™ uniques, isolants en caoutchouc

Specifications

THUNDER4250D

RMS Power measured at 12.5 Volts DC:
125 Watts x 1 into a 4 Ohm load with less than 1% Thd+N
250 Watts x 1 into a 2 Ohm load with less than 1% Thd+N
Dynamic Power measured at 14.4 Volts DC
200 Watts x 1 into a 4 Ohm load
350 Watts x 1 into a 2 Ohm load
Signal to Noise Ratio: ≥100dB A-Weighted
Damping Factor: >200
Frequency Response: 20Hz-200Hz
Maximum Input: 8Vrms
Thunder EQ: Variable Bass Boost (0-18dB) centered at 40Hz
Crossover: Variable 40Hz to 200Hz, 24dB/octave low pass
Dimensions: 7" x 9.75" x 2" (17.8cm x 24.8cm x 5.1cm)

9.9" x 9.75" x 2.1" (23.6cm x 24.8cm x 5.3cm) Including IsoFeet™

THUNDER6500D

RMS Power measured at 12.5 Volts DC:
250 Watts x 1 into a 4 Ohm load with less than 1% Thd+N
500 Watts x 1 into a 2 Ohm load with less than 1% Thd+N
Dynamic Power measured at 14.4 Volts DC
450 Watts x 1 into a 4 Ohm load
775 Watts x 1 into a 2 Ohm load
Signal to Noise Ratio: ≥100dB A-Weighted
Damping Factor: >200
Frequency Response: 20Hz-200Hz
Maximum Input: 8Vrms
Thunder EQ: Variable Bass Boost (0-18dB) centered at 40Hz
Crossover: Variable 40Hz to 200Hz, 24dB/octave low pass
Dimensions: 11.5" x 9.75" x 2" (29.2cm x 24.8cm x 5.1cm)

13.9" x 9.75" x 2.1" (36.6cm x 24.8cm x 5.3cm) Including IsoFeet™

THUNDER81000D

RMS Power measured at 12.5 Volts DC:
500 Watts x 1 into a 4 Ohm load with less than 2% Thd+N
1000 Watts x 1 into a 2 Ohm load with less than 2% Thd+N
Dynamic Power measured at 14.4 Volts DC
850 Watts x 1 into a 4 Ohm load
1500 Watts x 1 into a 2 Ohm load
Signal to Noise Ratio: ≥100dB A-Weighted
Damping Factor: >100
Frequency Response: 20Hz-200Hz
Maximum Input: 8Vrms
Thunder EQ: Variable Bass Boost (0-18dB) centered at 40Hz
Crossover: Variable 40Hz to 200Hz, 24dB/octave low pass
Dimensions:15.4" x 9.75" x 2".(40.1cm x 24.8cm x 5.1cm)

17.8" x 9.75" x 2.1" (45.2cm x 24.8cm x 5.3cm) Including IsoFeet™
Recommended Fuse = 150A

Caractéristiques