Ampeg V4BH manual Front Panel Controls and Their Use

V4BH Bass Amplifier

The Front Panel Controls and Their Use

	4	5	6			4	5	6		4	5	6	2	3	4	4	5	6		4	5	6
	3		7			3			7	3		7	1		5	3			7	3			7
	2		8		Hi	2			8	2		8				2			8	2			8	Standby/
	1		9			1			9	1		9				1			9	1			9
																								Power
	0		10	Lo		0		10		0		10				0		10		0	10
0dB	–15dB	Gain			Ultra Hi / Lo	Bass				Midrange			Frequency			Treble				Master					Standby	Power
1	2	3		4	5		6				7			8			9				10			11	12	13

1.0dB INPUT: The signal output from an instrument (active or passive – typically passive) or a line level signal may be con- nected here by means of a shielded instru- ment cable. The signal at this jack is sent into the preamp at full strength.

2.-15dB INPUT: The signal output from an instrument (active or passive – typically active) or a line level signal may be con- nected here by means of a shielded instru- ment cable. The signal at this jack is padded 15dB before it is sent into the pre- amp.

3.GAIN: This control adjusts the basic level of signal in the preamp.

4.ULTRA HI: This switch boosts high frequencies.

5.ULTRA LO: This switch, when depressed, provides emphasis to the low frequencies by boosting the low frequencies and selectively cutting the mid frequencies.

6.BASS: This is the primary low fre- quency control. It allows for 12dB of cut or boost at 40Hz.

7.MIDRANGE: This is the primary midrange control. It allows for 20dB of cut or 10dB of boost at the center fre- quency selected by the Frequency control (8).

8.FREQUENCY: Allows you to select the center frequency for the Midrange control (7), giving you a choice of five “voices” for the Midrange. The numbers correspond to the following center fre- quencies as indicated: 1=220Hz, 2=450Hz, 3=800Hz, 4=1.6kHz, 5=3kHz.

9.TREBLE: This is the primary high frequency control. It allows for 20dB of cut or 15dB of boost at 4kHz.

10.MASTER: This controls the signal level to the power amp and therefore the overall listening level. It also controls the level to the Preamp Out jack (20).

11.STANDBY/POWER LED: This is a dual-function LED. In Standby Mode, it glows red. In the On mode (when high voltage is applied to the tubes) it glows green. If it does not turn green in the On mode, there is no high voltage present and the unit needs servicing.

12.STANDBY: The Standby mode allows the tubes to warm up or remain warm without high voltage being applied to them. This extends tube life. This switch should be OFF when first turning the amplifier on. Allow the unit to warm up for 20 seconds before switching to the ON position. During short periods of non-use, the amp should be put into Standby mode.

13.POWER: This supplies AC power to the unit. Turn this switch on before turning on the Standby switch (12), as explained above.

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