Guild ThunderBass I User manual

Operating Instuctions—ThunderBass,
Quantum Bass, and Quantum X Amplifiers
INTRODUCTION
The ThunderBass I, ThunderBass I-A and Quantum X are designed for bass, guitar,
and organ.
The Quantum Basses are for use with electric bass ans organ only. The ThunderBasses
have 100 watt amplifier sections and the Quantum series all have 200 watt amplifiers.
The channel functions and controls are the same for both. The only difference in the
amplifier sections is the power rating.
PREVENTING OF SPEAKER DAMAGE
1. When plugging your instrument in or out of the amplifier input , always place the
Standby Switch (indicated by SBY) in "SBY" position, which is the "off "
position.
2. Use caution when raising the volume level to maximum output. When used with
electric bass, the Guild ThunderBass and Quantum Bass amplifiers are capable
of producing more power than the speakers can handle.
USE OF VOLUME CONTROLS
These amplifiers have sufficient gain to cause overloading with an average guitar when
the volume Controls are adjusted to maximum output. Once an amplifier reaches the
overload point, very little additional volume is produced, but the distortion level
increases exponentially.
Unless distortion is desired for some particular reasons, there is no justfication for
turning the volume Control beyond the setting which produces the maximum clean
output that the amplifier is capable of producing. The most favorable signal-to-noise
ratio (the least amount of hiss) is attained when the volume Control of the individual
channel is set at maximum level—clockwise—and the master Volume Control is at a
minimum setting.
Note: The Master Volume Control overrides the Volume Control of the individual
channel. Whatever the individual Volume Control settings, the Master Volume
Control raises the level of both channels simultaneously.
INPUTS: NORMAL AND HIGH GAIN
No.1 input is the high gain input. Unless overloading is experienced, use the No.1 input.
No.2 input would be used with guitars having pickups of unusually high output.
PROPER USE OF TONE CONTROLS AND TONE SWITCH
1. With Tone Controls centered and the Tone Switch in the top position, the
frequency response is flat. This is preferred position for microfone reproduction
and accordion amplification.
2. As the Tone Switch is moved from top to bottom position, the treble gain
increases significantly.
3. Experimantation with the various Tone Controls will provide the player with a
wide range of sound and tone.

BASS CHANNEL
1. With Tone Controls centered and the Tone Switch in the middle position, the
frequency respons is flat.
2. With the Tone Contrlol Switch in upper position, the sound is "harder" or
"brighter." With the Tone Switch in lower position, it is a "deep" or "rhythm"
sound. Maximum bass response is achieved with the switch in the lower position.
USE OF STANDBY (SBY) SWITCH
The Standby Switch activates an indicator light which gives you a visual as well as
audible indication of the Switch position. When the indicator light is on, the amplifier is
ready for use.
POLARITY SWITCH
Use of the Polarity Switch helps to eliminate excessive hum, string noise, and the effect
of minor shocks. It is located on the front panel.
REAR PANEL FEATURES
You will find an auxiliary AC outlet on the rear panel. This is convenient for the
addition of such accessories as the Guild P.A. System, Copicat or Echorec. The current
rating is printed below the outlet.
HUM BALANCE CONTROL
Each amplifier had a Hum Balance Control on the rear panel to minimize amplifier
hum and buzz. Correct hum-balancing procedure: Make sure that the Polarity Switch
(front panel) is in the most favorable position (least hum). Then disconnect the
instruments from the amplifier. With Volume controls at normal playing level, adjust
the Hum Balance Control for lowest hum. After the instruments are again plugged into
the amplifier, any hum that returns is the result of electric fields picked up by the guitar.
DOLLY ATTACHMENT
You will note a small hole with a metal bushing located on the bottom and/or side of
your amplifier speaker cabinet. An accessory dolly (Guild model TD1) is easily attached
with a special fitting on the dolly. By inserting this fitting and turning it one-quarter of a
turn, the dolly can be attached or detached.
GUILD
GUILD MUSICAL INSTRUMENTS, HOBOKEN, NEW JERSEY 07030
A DIVISION OF AVNET, INC.
No6949-F Litho in USA

Components list Thunderbass by Guild (Supply)
TR 1 Mains Transformer
V 1 Tube, 6GF7 or 6GF7A
D 1 Diode, 300 PIV or any other 4 Amp diode (500Volts)
D 2 Diode, 300 PIV or any other 4 Amp diode (500Volts)
D 3 Diode, 300 PIV or any other 4 Amp diode (500Volts)
S 1 Mains Switch mounted on front panel
L 1 Neon Lamp, mounted on front panel
Con. 1 Mains Auxilairy Connector (Max 4 Amp), mounted on back of chassis
P 1 Potmeter 250 Ohm/Lin
P 2 Potmeter 10K Ohm/Lin
R 1 Resistor 10 Ohm/5 Watt
R 2 Resistor 15K Ohm/10 Watt
R 3 Resistor 4K7 Ohm
R 4 Resistor 220K Ohm/2 Watt
R 5 Resistor 27K Ohm
R 6 Resistor 5 Ohm/5 Watt
R 7 Resistor 3K3 Ohm
R 8 Resistor 18K Ohm
R 9 Resistor 180K Ohm
R 10 Resistor 470 K Ohm
C 1 Capacitor 470nF/600V (x-type)
C 2 Capacitor 250uF/450V (electrolytic)
C 3 Capacitor 250uF/450V (electrolytic)
C 4 Capacitor 80uF/450V (electrolytic) C4 & C5 in one housing
C 5 Capacitor 80uF/450V (electrolytic) C4 & C5 in one housing
C 6 Capacitor 33uF/100V (electrolytic)
C 7 Capacitor 100uF/100V (electrolytic) C7 & C8 in one housing
C 8 Capacitor 50uF/100V (electrolytic) C7 & C8 in one housing
C 9 Capacitor 0,1uF/400V (film/foil)
C 10 Capacitor 2,2uF/450V (electrolytic)
All Resistors 0.5Watt unless Otherwise Specified

Components list Thunderbass by Guild (Pre Amp.)
V 6 Tube, ECC 83
V 7 Tube, ECC 83
V 8 Tube, 7247
L 1 Neon Lamp, indicates "Stand By" mounted on front panel
S 5 Stand By Switch, mounted on front panel
Normal 1 Guitar input Connector, Jack 6,3mm mounted on front panel
Normal 2 Guitar input Connector, Jack 6,3mm mounted on front panel
Bass 1 Guitar input Connector, Jack 6,3mm mounted on front panel
Bass 2 Guitar input Connector, Jack 6,3mm mounted on front panel
Con. 5 Connector, Jack 6.3mm, mounted on top side of chassis
P 5 Potmeter 3M Ohm
P 6 Potmeter 3M Ohm
P 7 Potmeter 1M Ohm
P 8 Potmeter 3M Ohm
P 9 Potmeter 3M Ohm
P 10 Potmeter 1M Ohm
R 36 Resistor 150K Ohm
R 37 Resistor 150K Ohm
R 38 Resistor 330K Ohm
R 39 Resistor 10K Ohm
R 40 Resistor 8K2 Ohm
R 41 Resistor 680 Ohm
R 42 Resistor 1K Ohm
R 43 Resistor 10K Ohm
R 44 Resistor 1K8 Ohm
R 45 Resistor 150K Ohm/2Watt
R 46 Resistor 1M Ohm
R 47 Resistor 1K Ohm
R 48 Resistor 150K Ohm/2Watt
R 49 Resistor 1M2 Ohm
R 50 Resistor 100K Ohm
R 51 Resistor 10K Ohm
R 52 Resistor 220K Ohm
R 53 Resistor 330K Ohm
R 54 Resistor 220K Ohm
R 55 Resistor 1K Ohm
R 56 Resistor 220K Ohm
R 57 Resistor 120K Ohm
R 58 Resistor 150K Ohm
R 59 Resistor 150K Ohm
R 60 Resistor 330K Ohm
R 61 Resistor 10K Ohm
R 62 Resistor 8K2 Ohm
R 63 Resistor 680 Ohm
R 64 Resistor 1K Ohm
R 65 Resistor 4K7 Ohm
R 66 Resistor 150K Ohm/2Watt
R 67 Resistor 56K Ohm
R 68 Resistor 330K Ohm
R 69 Resistor 1M Ohm
R 70 Resistor 6K8 Ohm
R 71 Resistor 1K Ohm
R 72 Resistor 150K Ohm/2Watt
R 73 Resistor 100K Ohm
R 74 Resistor 10K Ohm
R 75 Resistor 680K Ohm
All Resistors 0.5Watt unless Otherwise Specified

Components list Thunderbass by Guild (Pre Amp.)
R 76 Resistor 1K Ohm
R 77 Resistor 220K Ohm
R 78 Resistor 220K Ohm
R 79 Resistor 220K Ohm
R 80 Resistor 10K Ohm/3Watt
R 81 Resistor 10K Ohm/3Watt
R 82 Resistor 56K Ohm
R 83 Resistor Ohm
C 24 Capacitor 68nF/100V film/foil
C 25 Capacitor 33uF/25V electrolytic
C 26 Capacitor 10nF/100V ceramic
C 27 Capacitor 33nF/100V ceramic
C 28 Capacitor 0,1uF/400V film/foil
C 29 Capacitor 33uF/25V electrolytic
C 30 Capacitor 0,15uF/400V film/foil
C 31 Capacitor 10nF/200V film/foil
C 32 Capacitor 1nF/250V ceramic
C 33 Capacitor 1nF/250V ceramic
C 34 Capacitor 75pF/250V ceramic
C 35 Capacitor 3,3nF/400V film/foil
C 36 Capacitor 33nF/400V film/foil
C 37 Capacitor 33nF/400V film/foil
C 38 Capacitor 50nF/400V film/foil
C 39 Capacitor 33uF/25V electrolytic
C 40 Capacitor 50nF/400V film/foil
C 41 Capacitor 135pF/400V ceramic
C 42 Capacitor 68nF/100V film/foil
C 43 Capacitor 33uF/25V electrolytic
C 44 Capacitor 22nF/100V film/foil
C 45 Capacitor 22nF/100V film/foil
C 46 Capacitor 22nF/100V film/foil
C 47 Capacitor 0,1uF/400V film/foil
C 48 Capacitor 33uF/25V electrolytic
C 49 Capacitor 0,15uF/400V film/foil
C 50 Capacitor 10nF/200V film/foil
C 51 Capacitor 3,3nF/400V film/foil
C 52 Capacitor 33nF/400V film/foil
C 53 Capacitor 3,3nF/250V ceramic
C 54 Capacitor 33nF.250V film/foil
C 55 Capacitor 75pF/250V ceramic
C 56 Capacitor 50nF/400V film/foil
C 57 Capacitor 33uF/25V electrolytic
C 58 Capacitor 50nF/400V film/foil
C 59 Capacitor 135pF/400V ceramic
C 60 Capacitor 40uF/250V electrolytic (C60 & C61 in one housing)
C 61 Capacitor 40uF/250V electrolytic (C60 & C61 in one housing)
All Resistors 0.5Watt unless Otherwise Specified

GuiM Outputstage - SHEET
1 NOTES:
ALL D.C. VOLTAGE MEASUREMENTSARE RESPECTT0GROUND
AND ARETAKENAT 230V LINEVOLTAGEWITH 8 OHMLOAD
CONNECTEDT0OUTPUTAND NO SIGNALAPPLIEDT0INPUT
ADJUST EACHOUTPUTTUBE BIAS CONTROLT0PROVIDE0.3V D.C.
ENG: 0.L LUGT
PROJECT: THUNDERBASSBY GUILD (OUTPUTSTRAGE)
COMPANY: OCTHODE
ADDRESS: FERDINAND BOLLAAN I2
CITY 2251 JD VOORSCHOTEN
COUNTRY: NEMERLANDS
INITiPi 1506-19sB1
w2
A
d\
AUX.
OUTPUT
8 OHM

Components list Thunderbass by Guild (Outputstage)
TR 2 Output Transformer
V 2 Tube, ECC 83
V 3 Tube, 7247
V 4 Tube, 6550
V 5 Tube, 6550
Con. 2 Output Connector, Jack 6.3mm 8 Ohm, mounted on rear side of chassis
Con. 3 Auxilary Output Connector, Jack 6.3mm 8 Ohm, mounted on short side of chassis
Con. 4 Bias Test Connector, mounted on rear side of chassis
P 3 Potmeter 3K/Lin
P 4 Potmeter 3K/Lin
R 11 Resistor 1M Ohm
R 12 Resistor 330K Ohm
R 13 Resistor 100K Ohm
R 14 Resistor 680 Ohm
R 15 Resistor 22K Ohm
R 16 Resistor 1K8 Ohm
R 17 Resistor 220K Ohm
R 18 Resistor 10M Ohm
R 19 Resistor 1M Ohm
R 20 Resistor 1K Ohm
R 21 Resistor 100K Ohm
R 22 Resistor 330K Ohm
R 23 Resistor 1K Ohm
R 24 Resistor 14K Ohm/2Watt
R 25 Resistor 15K Ohm/2Watt
R 26 Resistor 6K8 Ohm
R 27 Resistor 6K8 Ohm
R 28 Resistor 6K8 Ohm
R 29 Resistor 91K Ohm
R 30 Resistor 91K Ohm
R 31 Resistor 1K Ohm
R 32 Resistor 4K7 Ohm
R 33 Resistor 1K Ohm
R 34 Resistor 6,8 Ohm
R 35 Resistor 6,8 Ohm
C 11 Capacitor 0,1uF/400V film/foil
C 12 Capacitor 15pF Ceramic
C 13 Capacitor 75pF Ceramic
C 14 Capacitor 0,1uF/400V film/foil
C 15 Capacitor 0,75uF/250V film/foil
C 16 Capacitor 0,1uF/400V film/foil
C 17 Capacitor 10nF/200V film/foil
C 18 Capacitor 47pF Ceramic
C 19 Capacitor 0,1uF/400V film/foil
C 20 Capacitor 0,27uF/400V film/foil
C 21 Capacitor 0,27uF/400V film/foil
C 22 Capacitor 300nF Ceramic
C 23 Capacitor 1nF Ceramic
All Resistors 0.5Watt unless Otherwise Specified