Precision Power TD 1250 Owners Manual

Owners Manual TD 1250

CONTENTS

(click on a topic to view)

CONGRATULATIONS ENDPANEL LAYOUT

FEATURES / SPECIFICATIONS ENDPANEL LAYOUT (cont.)

INSTALLATION TROUBLESHOOTING

WIRING TROUBLESHOOTING

POWER / GROUND TROUBLESHOOTING (cont.)

CONNECTIONS TROUBLESHOOTING (cont.)

CONNECTIONS (cont.) SYSTEM DIAGRAM 1 / 2

INPUTS / CONNECTIONS BLOCK DIAGRAM

INPUTS WARRANTY

(cont.)

Thank you for choosing TUBE DRIVER. Tube Drivers musicality and absolute sonic
transparency allow accurate reproduction of recorded music enabling you to hear as well as
feel the music the way the artist intended. These handcrafted amplifiers feature full differential
“front ends” based upon a true instrumentation amplifier topology. Tube Drivers utilize only
the highest quality Svetlana tubes in our unique configurations. All of the internal amplifier
stages have been designed to have ultra-wide bandwidth together with a high degree of
linearity. The tubes used in these amplifiers provide both voltage gain and current gain where
they are connected in Cascode and Cathode Follower configurations. D.C. servos are used
to control any D.C. offset. These servos are critically positioned in the circuit so that not only
is D.C. offset eliminated but also any subtle differences between tubes are internally
compensated. These tube stages are then connected to a high current BiPolar output stage
that uses the same audiophile quality Sanken output devices featured in the PrecisionPower
2500F1.The output stages receive their power from a highly regulated D.C. power supply
which enhances their performance significantly. Very little negative feedback is used. Low
feedback designs have greatly improved sound quality having an extremely warm and open
sound with enhanced musicality consistent with only the highest quality home tube amplifiers.

Service

Do not attempt to service TUBE DRIVER products yourself.
Performing exploratory surgery on your audio equipment yourself
will void the warranty . Many parts of your TUBE DRIVER gear
are custom built to our specifications. Our factory parts are not
made available to anyone else nor are they for sale. Our goal
is to make sure that your TUBE DRIVER product will always
sound as good as the day it was purchased. Contact your
authorized TUBE DRIVER dealer about obtaining any warranty
service through TUBE DRIVER.(See Warranty insde back cover)

Model
Serial Number
Purchase Date

Caution!

The extended use of a high powered audio system may
result in hearing loss or damage. While TUBE DRIVER

systems are capable of
incredible accuracy, they are also designed for you to
enjoy at more reasonable levels all of the sonic subtleties
created by musicians. Please observe all local sound
ordinances.

"Concert Level"

volumes with

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Fully regulated adaptive MosFET power supply
Balanced Mini-Din Input
High Voltage Input Capability with Input Attenuation Switch
Gold Plated RCA Input connectors
Three Year Warranty when installed by an Authorized
Completely Designed and Handcrafted in the USA

TD

dealer

Specifications

Power Bandwidth: 5 Hz -50 KHz
Total Harmonic Distortion: 0.2% or less (A-weighted)
Input Topology: Balanced Differential
Input Sensitivity: 500mV - 12 volts RMS
Input Impedance: 10K Ohms
Output Impedance: 2 - 16 Ohms

Continuous Output Power

TD1250

250 WRMS x 1 @ 4 Ohms
500 WRMS x 1 @ 2 Ohms

Dimensions

TD1250

Length = 17”
Height = 3.2”
Width = 9.25”

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Tools/Parts Needed for Installation

Small flat blade screwdriver
Phillips screwdriver (#2 or medium sized)
Wire cutters
Wire strippers
4 – #6 round head screws, and 1 – #8 sheet metal screw

(or nut, bolt, and star washer)
2 – Ring connectors (large enough to accommodate your method of grounding)
In-line fuse or circuit breaker — see fuse requirements below
Power and groundwire — see Power Wire Calculator on the next page
Speaker wire — 16 gauge or larger
Grommets (sized to work with the power wire you plan to use in your installa-

tion)
Tube of silicone sealant

(not supplied)

Fuse Requirements

Recommended Fuse Rating for TD1250 i s 10 0 Amps

You will need to install an in-line fuse or circuit breaker in the power wire
within 18” of the battery. This fuse or circuit breaker protects your vehicle
from fire in case the power wire shorts to the vehicle bod y. If you are only using

one amplifier, use the recommended fuse rating. If you are using more than one
amplifier, add up the fuse ratings for all amplifiers, and use this sum for your main
fuse or circuit breaker. Use a power distribution block or fuse near your amplifiers
with the appropriate fuse for each individual power wire.

The information below is a basic formula you can use to determine approximate
current draw. A 50% amplifier ef ficiency rating is used as an average. This formula
is only a guideline. Using wire of a larger gauge can only improve the current transfer
of your system. Do not use smaller gauge wire.

Total 4-Ohm rated RMS output x 2 = Total Input Wattage

Total Input Wattage/Supply Voltage = Current Draw (in Amps)

Example:

Your TD1250 has 1 channels at 250 watts RMS into 4-Ohms
(250 x 2 =500). You would use the formula below:

250W x 2 = 500W/12.5V = 40 Amps Total Current Draw

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Power Wire Calculator

Recommended MINIMUM Gauge

Total Current Dra w Length of Wire to Run (in Feet)

(in Amps) < 3 4 - 7 7 - 10 10 - 13 13-16 16-19 19-22 22-28

0 - 20 14 12 12 10 10 8 8 8

20 - 35 12 10 8 8 6 6 8 4

35 - 50 10 8 8 6 6 4 4 4

50 - 65 8 8 6 4 4 4 4 2

65 - 85 6 6 4 4 2 2 2 0

85 - 105 6 6 4 2 2 2 2 0

105 - 125 4 4 4 2 2 0 0 0

125 - 150 2 2 2 2 0 0 0 0

Warning!

Amplifiers Generate Heat!

Y ou can mount the TUBE DRIVER in any position, even upside-down. However,
you must maintain proper airflow. Do not install your TUBE DRIVER under
carpets or enclose it behind airtight panels. In trunk-mounted applications, be sure
to provide venting for air circulation. Let the amplifier breathe. Without adequate
air circulation, your Tube Driver will turn itself down to protect itself.

Mounting

Y ou need to mount your TUB E D RIVER securely in your vehicle to prevent damage.
You may mount the system right-side up, on its side, or upside-down, provided
there is adequate ventilation.

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Warning!

To prevent a short to ground, disconnect the negative (-) terminal of the system’s
battery before you begin. If the power cable shorts to ground, current will continue
to flow until the short is opened, the main fuse blows, the battery explodes, or the
wire melts.

Reconnect the terminal only after you make all connections.

Grounding

Your TUBEDRIVER is designed to operate from a car’s positive 12 volt, negative
ground electrical system. The ground wire should be the same gauge as the power
wire indicated in the chart.

The main power cable should run from the amplifier location, through or under the
vehicle, to the battery . Y ou must use a grommet wherever the cable passes through
a steel panel to prevent an eventual short to ground.

The ground connection is the most important part of any installation. If the
connections are poor and/or the resistance is high, the resulting drops in voltage
will rob you of amplifier power and may allow noise to enter your system. Your new
Tube Driver features a fully regulated power supply. It will make full power even if
the voltage changes. It will draw more current at lower voltages to make that power.
Lower voltage and high cable resistance means more total current draw. Using a
digital multimeter (DMM), try to get cable resistance as low as possible. If resistance
is too high, use a larger gauge wire. T ry to ground your system to a single point in
the vehicle. In larger systems, use distribution blocks and run both power and ground
cables directly to the system battery.

Remote Turn-on

IMPORT ANT! Your new Tube Driver is equipped with our unique tube warm-up
circuit. When your system is turned on, The LED labeled “WARM UP” will
illuminate and full power is applied to the tube heaters for appr ox. 35 seconds.
The internal fan will then turn on and two seconds later the amp outputs will
be switched on. The system will then play as normal.

You must connect a wire to the remote (REM) terminal (located in the speaker
terminal plug) of your amplifier to power on your TUBEDRIVER. The source unit
normally provides a remote amp turn-on or power antenna lead that provides this
+12 volts when you turn on the unit.

• Run a wire from the chosen turn-on lead to the REM connection

of your TUBEDRIVER (See Endpanel Lay out: Page 10)

• Tighten the connection

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