Crate Stealth GT-100H Professional Series Amplifier - Owner's Manual

Congratulations! Your love of performing and driving ambition to be the best have brought you to a turning point in your musical career: the Stealth GT-100H Professional Series guitar amplifier. An all-tube, 100 watt powerhouse of an amplifier designed to take you to the top. And keep you there.

We know something about you: we know you were never impressed with those "toys" that some of your friends called amplifiers. We know you were holding out until someone offered you an American-made, affordable piece of professional equipment you could really sink your teeth into. A serious amplifier, designed for a serious musician: an amp with the sounds you've always looked for, the power you've always dreamed about, and the reliability you know you'll need. And all with a name you know you can trust: CRATE.

Like all Crate products, your Stealth GT-100H is made with pride in America, using only the best components. Extensive testing at the hands and ears of skilled technicians and musicians ensures you that this amplifier is the absolute best it can be.

In order to get the most out of your new amplifier, we strongly urge you to go over the information contained in this manual before you begin playing.

And thank you for choosing CRATE.

SOUND LEVEL dBA (SLOW RESPONSE)	DURATION PER DAY IN HOURS
90	8
92	6
95	4
97	3
100	2
102	1-1/2
105	1
110	1/2
115	1/4 or less

ABOUT THE STEALTH GT-100H:

The Crate GT-100H is an all-tube, feature-packed professional stage amp, with three different sound and level settings readily available at the touch of a footswitch. Rugged construction, reliable American craftsmanship and 100 watts of pure tube power are trademarks of this new and impressive piece of professional musicians' equipment. The GT-100H features two distinctly different 12AX7 tube driven channels: one with the classic tube rhythm sounds and one offering you some of the finest lead and overdrive sounds of any amplifier.

Each channel features an all-tube preamp section with input attenuators and three bands of EQ for total tone control. In addition, Channel 2 also gives you two separate, footswitchable Gain controls which work independently, giving you TWO separate sounds and levels for the 3 tube, 7 gain stage distortion channel.

An easy-access front-panel "Aux In" jack lets you connect a drum machine, tape deck, or CD player right into the amplifier, allowing your guitar signal to pass from the preamp so you can "rehearse" with the music. Additional features such as an Effects Loop, a Line Out jack and an Extension Speaker jack further increase your possibilities and add to the flexibility and versatility of this unique and extraordinary amplifier.

FEATURES OVERVIEW:

Given below is a quick overview of the GT-100H's features and controls. Additional information can be found on the pages indicated.

All Tube Preamp and Power Amp: Classic tube sound with Crate's legendary performance and reliability.
Two Completely Separate Channels: Independent Preamp levels, 3-band EQ's, Reverb and Master levels. (page 3)
Two Gain Controls: (Channel 2) Footswitchable. Independently adjustable. Almost like getting a third channel. (page 4)
Aux In Jack: Allows insertion of drum machine or music source. Great for practicing or performing. (page 3)
Total Footswitch Control: Channel selection. Choice of two Gains for Channel 2. (page 4, page 6)
External Speaker Jack: Standard 1/4" mono phone jack. Parallel connection. (page 6)
Effects Loop: 1/4" Line Out/Line In jacks. Allows external signal processor connection. (page 6)
Line Out Jack: Frequency compensated to simulate speaker cabinet. (page 6)
Impedance Selector Switch: For optimum speaker matching using virtually any cabinet configurations. (page 6)

THE GT-100H FRONT PANEL:

[Illustration of the front panel with numbered controls]

POWER: Heavy-duty rocker-type switch to turn the amplifier ON (up position) or OFF (down position). The Power LED (#2) indicates operation.
POWER LED: Glows red when the GT-100H is on, indicating the amplifier is activated and ready.
PRESENCE: Adjusts high-frequency overtones and harmonics. Turning left reduces, turning right increases. Provides up to 10dB boost or cut at 8kHz.
MASTER, CHANNEL 2: Adjusts the output level for Channel 2. Full left means little to no signal. Turning right increases signal strength to the power amplifier, affecting Speaker, Line Out, and Effects Loop Send.
MASTER, CHANNEL 1: Adjusts the output level for Channel 1. Full left means little to no signal. Turning right increases signal strength to the power amplifier, affecting Speaker, Line Out, and Effects Loop Send.
REVERB, CHANNEL 2: Adjusts the amount of reverb for Channel 2. Full left is "dry" (no reverb). Turning right increases reverb, with maximum at full right. This reverb is more traditional, with less bottom end than Channel 1.
REVERB, CHANNEL 1: Adjusts the amount of reverb for Channel 1. Full left is "dry" (no reverb). Turning right increases reverb, with maximum at full right. This reverb is deeper and fatter, suited for clean sounds.
AUX IN: Stereo jack to feed a drum machine, tape or CD player into the internal power amp. Allows practice or playing along with music. WARNING: This jack connects directly to the power amp. Do not plug high-level signals into it. Exercise caution and use an input pad if necessary.

Channel 2 Controls:

LOW: Adjusts Channel 2's low frequency output. Center is "flat." Left reduces, right increases. Provides up to 16dB boost or cut at 40Hz.
MID: Adjusts Channel 2's midrange output. Center is "flat." Left reduces, right increases. Provides up to 13dB boost or cut at 500Hz, affecting the "voice" of your guitar's sound.
HIGH: Adjusts Channel 2's high frequency output. Center is "flat." Left reduces, right increases. Provides up to 16dB boost or cut at 5kHz, adjusting crispness or "bite."
GAIN 2: Adds tube distortion to Channel 2's signal, independently from Gain 1. Effects are similar to Gain 1. NOTE: If a footswitch is not connected, only Gain 1 is active; Gain 2 has no effect.
GAIN 1: Adds tube distortion to Channel 2's signal, creating a variety of sounds and levels. Use with Preamp and Master Level controls. Full left has no added distortion. Turning right adds distortion and increases output level. NOTE: If a footswitch is not connected, only Gain 1 is active; Gain 2 has no effect.
PREAMP: Gain control for Channel 2's preamp section, controlling volume and tube compression. Use with Master Level control (#18). Full left means no signal. Turning towards center increases signal level and compression. Full right provides full strength with tube preamp distortion.
LED: Glows red when Channel 2 is activated via the front-panel Select switch (#16) or a footswitch.
SELECT: Pushbutton switch to select Channel 1 (OUT position) or Channel 2 (IN position). The LED (#15) indicates Channel 2 selection.

Channel 1 Controls:

LOW: Adjusts Channel 1's low frequency output. Center is "flat." Left reduces, right increases. Provides up to 16dB boost or cut at 40Hz.
MID: Adjusts Channel 1's midrange output. Center is "flat." Left reduces, right increases. Provides up to 13dB boost or cut at 500Hz, affecting the "voice" of your guitar's sound.
HIGH: Adjusts Channel 1's high frequency output. Center is "flat." Left reduces, right increases. Provides up to 16dB boost or cut at 5kHz, adjusting crispness or "bite."
PREAMP: Gain control for Channel 1's preamp section, controlling volume and tube compression. Use with Master Level control (#5). Full left means no signal. Turning towards center increases signal level and compression. Full right provides full strength with slight clean tube compression.
INPUT: Connect your guitar here using a shielded instrument cable.

THE GT-100H REAR PANEL:

[Illustration of the rear panel with numbered controls]

IMPEDANCE SELECTOR: Match amplifier impedance to speaker cabinet(s). Set to 8 ohm or 16 ohm position based on total speaker impedance. IMPORTANT: Always keep total impedance at 8 or 16 ohms!

Cab. Imp.	# of Cabs.	Total Imp.
8 ohms	1	8 ohms
16 ohms	1	16 ohms
8 ohms	2	8 ohms

SPEAKER: Connect to a single speaker cabinet. Use both jacks to connect to two cabinets. ONLY use speaker cabinets with 8 ohm or higher impedance. Use heavy-duty speaker cables (not instrument patch cords). Use #23 first.
LINE OUT: Supplies a pre-amplified, post-EQ signal to an external amplifier, mixing board, or recording console. Unbalanced mono 1/4" jack.
FOOTSWITCH: Plug in a dual footswitch here for remote control of channel selection and Gain 1/Gain 2 for Channel 2. Footswitch overrides front panel Select switch (#16). NOTE: This is a STEREO 1/4" jack: "ring" controls Gains, "tip" controls channel selection, "sleeve" is ground. Use a stereo-plug equipped footswitch (e.g., Crate FS-60).
EFFECTS LOOP RETURN: Connect a shielded cable from the output of an external signal processor to this jack to complete the loop. Returns the processed signal to the internal amplifier.
EFFECTS LOOP SEND: Connect a shielded cable from this jack to the input of an external signal processor. Sends the pre-amplified signal to the device for processing.
B+ FUSE: Protects output tubes from overload. Replace with a 2A 120V slo-blow fuse. If fuse blows repeatedly, check AC source; if okay, contact Crate dealer.
FUSE: Protects amplifier from AC power source issues. Replace with a 5A 120V slo-blow fuse. If fuse blows repeatedly, check AC source; if okay, contact Crate dealer.
POWER CORD: Heavy-duty, grounded, three-wire power cord. Plug into a safely-wired, grounded 120 volt, 60 cycle AC power outlet. DO NOT defeat the ground connection. For units outside the US, check rear panel for power rating and follow guidelines.

SOME SUGGESTED SETTINGS:

CRUNCHY EDGE:

[Illustration of controls set for Crunchy Edge]

Gain 2 can be set as desired for solos.

SPARKLING CLEAN:

[Illustration of controls set for Sparkling Clean]

ROCK RHYTHM:

[Illustration of controls set for Rock Rhythm]

Gain 2 can be set as desired for solos or for more distortion.

FAT CLEAN:

[Illustration of controls set for Fat Clean]

BEDROOM SETTINGS:

[Illustration of controls set for Bedroom Settings]

CLUB SETTINGS:

[Illustration of controls set for Club Settings]

Gain 2 can be set as desired for solos.

A WORD ABOUT TUBES:

Your GT-100H comes equipped with EL-34 power tubes, known for their "British Rock" sound and earlier distortion. For a more traditional "American Rock" sound or heavy metal, consider replacing EL-34s with 6550 power tubes at an authorized Crate service center. 6550s offer more clean power and headroom.

NOTE: Tube replacement and biasing adjustments should only be performed by a qualified service center.

Vacuum tubes are susceptible to vibrations, heat, and age. Worn power tubes can cause weakness, loss of punch, and fading sound. Power tubes work in pairs and should be replaced simultaneously with matched tubes. Your dealer can recommend suitable replacement tubes.

Preamp tubes generally last longer. Worn preamp tubes can cause squealing, noise, loss of gain, or complete failure. A service center can identify faulty preamp tubes.

The GT-100H uses high-quality tubes for excellent sound and performance. To maintain peak performance:

Match speaker cabinet impedance to the amplifier to prevent premature tube wear.
In cold weather, allow the amplifier to warm up to room temperature before use to prevent cold-cracked glass.
Allow the amplifier to cool after use before moving to prevent damage from vibrations.
Replace output tubes regularly (annually, or every 4-6 months for heavy use).
Always have the amplifier's biasing checked after replacing output tubes. Improper biasing can cause overheating (glowing gray plates) and poor sound. Do not operate the amplifier if these symptoms occur.
Let the amplifier idle for 5-10 minutes after new tubes are installed to allow stabilization.
Protect the amplifier from dust and moisture. If liquids spill or the unit is dropped/jarred, have it checked by a service center before use.

Proper maintenance and cleaning, along with regular service, ensures optimal performance and longevity.

SYSTEM BLOCK DIAGRAM:

[System Block Diagram illustration showing signal flow through preamp, effects loop, power amp, and outputs]

All preamp tubes are 12AX7's.

Output tubes: EL-34.

GT-100H TECHNICAL SPECIFICATIONS:


Output Power Rating	100 watts RMS @5% THD 8 ohm load, 120VAC
Gain	Channel 1: 60dB, tones at "5" @ 1kHz Channel 2: 78dB, tones at "5" @ 1kHz
Tone Control Range	Channel 1: Low: 16dB @ 40Hz Mid: 13dB @ 316Hz High: 16dB @ 5kHz Channel 2: Low: 16dB @ 40Hz Mid: 16dB @ 500Hz High: 12dB @ 5kHz Presence: 10dB @ 8kHz
Signal to Noise Ratio	Channel 1: -55dB, all controls @ "10" Channel 2: -52dB, all controls @ "10"
Input Impedance	0dB/1m ohm
Maximum Signal Accepted	2V peak to peak
Tube Type	Preamp: 12AX7 (3) Power Amp: EL-34 (4) (6550 compatible)
Line Out Level	4.5V RMS @ 1kHz
Fuses	Mains: 5A Slo-Blow B+: 2A Slo-Blow
Size and Weight	11.625"H x 30.75"W x 11"D 45 lbs.

The GT-100H is covered with a high-quality carpet-like material; brush clean as needed. Never spray cleaning agents directly onto the cabinet, and stay away from abrasive cleaners which could damage the finish.

Crate continually develops new products, as well as improves existing ones. For this reason, the specifications and information in this Crate manual are subject to change without notice.

CRATE/SLM ELECTRONICS, A DIVISION OF ST. LOUIS MUSIC, 1400 FERGUSON, ST. LOUIS, MO. 63133
P/N 47-631-01