Ampeg SVT450H Bass Head
In the world of high performance bass amps, the Ampeg SVT-450H gives you more power, performance and flexibility than any other bass amp in its class. And if we didn’t tell you, you’d swear the SVT-450H was a tube amplifier. Producing warm, tube-like performance at stunning volume levels (it’s rated at 450-Watts RMS at 4 Ohms), the SVT-450H uses MOSFET technology and offers a full complement of professional features, such as: Optocoupler Limiters, which prevent unwanted power amp distortion, no matter how loudly you play; and an onboard 9-Band Graphic EQ that allows you to sculpt a tone that is second to none. In spite of all these amazing features, the SVT-450H is still our most affordable bass head.
Control panels：
- 0dB (INPUT): The signal output from an instrument (active or passive) or a line level signal may be connected here by means of a shielded instrument cable.
- PAD: This switch, when depressed, attenuates the input signal by 15dB. Attenuation allows the Gain control (#4) to be used in a more usable (higher) position. If clipping is indicated with the Gain control way down, attenuation is needed.
- PEAK: This LED illuminates when the signal level into the preamp (excluding the Graphic EQ) approaches clipping. Adjust the Gain control (#4) until a strong signal from your instrument causes this LED to flicker. NOTE: If the LED illuminates frequently with the Gain at a low setting, use the Pad (#2) to attenuate the signal and readjust the Gain.
- GAIN: Use this control to adjust the level of the signal entering the preamp stage. Adjust this control until the Peak LED (#3) flashes on strong signal peaks (but is not illuminated constantly while playing). To obtain the best signal to noise ratio, set the Gain control as described above and adjust the Master control (#8) to obtain the desired volume level.
- BASS: Use this control to adjust the low frequency level of the amplifier. This control provides 15dB of cut or 13dB of boost at 40Hz. The low frequency output is flat at the center position.
- ULTRA MID: Use this control to adjust the midrange frequency level of the amplifier. This control provides 13dB of cut or 5dB of boost at 400Hz. The midrange frequency output is flat at the center position. Rotate the control counter clockwise for a “contoured”sound (more distant, less midrange output) or clockwise for a sound which really cuts through.
- TREBLE: Use this control to adjust the high frequency level of the amplifier. This control provides 21dB of cut or 16dB of boost at 8kHz. The high frequency output is flat at the center position.
- MASTER: Use this control to adjust the overall output level of the amplifier. For the lowest possible noise level, adjust the Gain control as described in #4 and use this control to obtain the desired volume level. The Effects Loop and Balanced Out (#20 - 24) are not affected by the Master control.
- LIMIT: The SVT450H uses an internal Optocoupler Limiter to assist in keeping the amplifier’s output “clean” at extreme volume levels. (All amplifiers may begin to clip their output signals as they approach maximum output levels, resulting in potentially damaging distortion.) To engage the Limiter, depress this switch. The adjacent LED illuminates when the limiter circuit is activated, indicating that the amplifier is nearing full output and the limiter is keeping peak signals from clipping the output.
- EQ ON: This switch, when depressed, activates the Graphic EQ. The adjacent LED illuminates when the EQ is active.
- GRAPHIC EQUALIZER: Use these sliders to control the amplitude of the frequencies indicated below each control. The center position of each control is flat: sliding the control upward increases the output level of that frequency; sliding the control downward decreases it.
- ON: This LED illuminates when the amplifier is on.
- POWER: Use this switch to turn the amplifier on (top of the switch depressed) and off (bottom of the switch depressed).
- (FAN): The temperature controlled, variable speed fan draws cool air into the amplifier and forces heat out through the exhaust vents (also on the rear panel, between the speaker jacks and the power amp in jack). Do not obstruct the fan or vent hole openings.
- (FUSE): The fuse helps protect the unit from damage due to overload conditions. If the fuse fails, replace it only with the same size and type. If the fuse fails repeatedly, check the line voltage or contact an Ampeg Service Center.
- AC LINE IN: Firmly insert the supplied AC power cord into this socket until it is fully seated. This grounded power cord is to be plugged into a grounded power outlet, wired to current electric codes and compatible with voltage, power, and frequency requirements stated on the rear panel. Do no attempt to defeat the safety ground connection.
- SPEAKERS: The 1/4” jacks offer a convenient method of connecting to speaker cabinets using cables terminated with 1/4” plugs. However, when using the amplifier at or near its full output power, using the Speakon® jack is recommended. (Pin 1+ = hot, pin 1- = return.)
NOTE: When connecting multiple speaker cabinets to the amplifier, keep the overall impedance at or above 4 ohms. The following chart shows the total impedance load when connecting speaker cabinets in parallel:
- POWER AMP IN: This mono jack allows you to feed the preamp output of another amplifier to the input of the SVT450H’s internal power amp. This bypasses the preamp circuitry of the SVT450H.
- PREAMP OUT: A post-EQ signal from this jack may be sent to the house mixing board, recording console, or an external amplifier.
- EFFECTS RETURN: Use this jack to connect the output signal from an external effect to the amplifier by means of a shielded signal cable.
- EFFECTS SEND: Use this jack to send a signal to the input of an external effect by means of a shielded signal cable.
- -20dB/0dB: This switch, when depressed, attenuates the signal at the Bal. Out jack (#24) by 20dB.
- POST/PRE: This switch, when depressed, sends a post-EQ signal to the Bal. Out jack (#24). When this switch in the out position, the signal at the Bal. Out jack (#24) is pre-EQ.
- BAL. OUT: This XLR connector provides a balanced preamp output signal for connecting to the house mixing board, a recording console, or an external amplifier with balanced inputs. The signal at this jack can be set to be pre or post EQ by means of the Post/Pre switch (#23). The level of the signal can be adjusted for mic or line type inputs by means of the -20dB/0dB switch (#22).
Specification:
