User manual BBE SOUND 381

[. . . ] In some cases, the fundamental components may be so time-shifted that they reach the listener's ear ahead of some or all of the harmonic components. This change in the phase and amplitude relationship on the harmonic and fundamental frequencies is technically called "envelope distortion. " The listener perceives this loss of sound integrity in the reproduced sound as "muddy" and "smeared. " In the extreme, it can become difficult to tell the difference between musical instruments, for example, an oboe and a clarinet. conducted extensive studies of numerous speaker systems over a ten year period. With this knowledge, it became possible to identify the characteristics of an ideal speaker and to distill the corrections necessary to return the fundamental and harmonic frequency structures to their correct order. [. . . ] While there is no absolutely flat position, the response is reasonably flat with the controls set at TREBLE: 2, MID: 0, BASS: 2, with the bright switch off. The circuit can be described as interacting, such that when the TREBLE and BASS tone controls are turned to 0 and the MID tone control is turned to -10, then no signal is passed at all. Para-mids 6. FREQ: A range from 250hz to 1000hz is adjustable with the FREQ knob. GAIN: Plus or minus 12dB. 3 Compressor 8. LEVEL: This is a "soft-knee" compressor using a photo-optical cell as it's attenuating element for controlling gain-reduction. The single-knob LEVEL control will lower the threshold at which gain reduction begins and increase the ratio of input vs. output, simultaneously, as it is rotated in the clockwise direction from "0" to "10". IN/OUT: When switched to the "IN" position, the compressor circuit will be engaged as indicated by the green LED. When the incoming signal reaches the threshold, determined by the position of the LEVEL control, the yellow LED indicates that compression is taking place. This switch is superceded by the use of the optional FS-381 footswitch. BBE Process 10. LO CONTOUR: This control is a low frequency adjustment for the BBE Process. This is a useful feature in eliminating a ground loop between the 381 and any subsequent component in the signal chain. Output 6. DI OUT: This is a transformerless electronically balanced low impedance output. Use this output to feed long cable runs or microphone level inputs on a mixing console or recorder 7. MAIN OUT: This unbalanced output is used to connect the BBE 381 Pre-amp to the next subsequent component in the system, i. e. RETURN: Use this jack to connect the 381 to an effects processor's output. SEND: Use this jack to connect the 381 to an effects processor's input. The send jack can also be used as to feed the input of a guitar tuner. FUS E F E US FUSE 3 4 5 6 7 8 9 5 Specifications Frequency Response: . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Hz ­ 30kHz +/-3dB Signal to Noise: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100dB@unity THD: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . less than 0. 02% Maximum Output: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +22dBu Noise: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -77 dBu @ unity gain, eq flat Input Impedance: Passive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Meg Ohm Active . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 K Ohm Output Impedance: Balanced XLR . . . . . . . . . . . . . . . . . . . . . . . . . . . 600 Ohms, Pin #2 hot or "+" Unbalanced 1/4" . . . . . . . . . . . . . . . . . . . . . 1K Ohms Interactive EQ: Treble (boost only) . . . . . . . . . . . . . . . . . . 18dB@ 6kHz Mid (cut only) . . . . . . . . . . . . . . . . . . . . . . . . . . . 12dB@ 300Hz Bass (boost only) . . . . . . . . . . . . . . . . . . . . . 16db@ 40Hz Bright Switch: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +8dB@ 5kHz, eq flat Para-mids: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +/- 12dB from 250Hz to 1kHz * 0dBu = 0. 775mVrms Power Requirements: . . . . . . . . . . . . . . . . . . . . . . . . . . . U. S. , Canada & Japan models: 120VAC, 50/60Hz, 8 WATTS Standard model: 220VAC, 50/60Hz, 8 WATTS Fuse: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Replace with the same type FASTBLOW fuse U. S. , Canada & Japan models: . 5A, 250VAC fast-blow type All others: . 250A, 250VAC fast-blow type Dimensions: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19"(W) x 5. 5"(D) x 1. 7"(H) Shipping Weight: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 lbs. Note: Due to continuing product improvement, specifications and design are subject to change without notice. General Operation In order to reduce the risk of damage to any equipment, properly connect all audio and power cables before turning on any components in the system. Most important of all, ALWAYS TURN ON THE POWER AMPLIFIER LAST TO AVOID DAMAGING THE SPEAKERS OR THE AMP. The Bass and Treble controls are mainly "boost" and the Mid control only "cut". While there is no absolutely flat position, the response is reasonably flat with the controls set at TREBLE:2, MID:10, BASS: 2, with the bright switch off. [. . . ] The Volume control will simultaneously adjust the 381's output volume from both outputs: The Balanced and Unbalanced outputs. Use either the Unbalanced or the Balanced output to connect to a power amp or a mixing console. The Unbalanced outputs are 1/4" monaural phone plugs while the Balanced output is a male XLR connector with a Ground Lift switch to eliminate any multiple ground connections. 6 LIVE APPLICATIONS from DI Out from Main Out Snake to Mic Input Combo amp or power amp and speakers Mixing console from Main Out from Send Tuner Power amp and speakers 7 Combo a RECORDING APPLICATIONS from DI Out to Mic Input -orMain Out to Line Input 50 40 30 20 10 0 Combo a Recorder Mixing console from Main Out to Line Input -orDI Out to Mic Input Computer recording interface Computer 8 Service We recommend that if at all possible, a BBE 381 which requires service be sent to our facility in Huntington Beach, California. We request that a "RETURN AUTHORIZATION" be issued by the dealer from whom you purchased the unit. [. . . ]