User Guide and Reference Manual ® i TABLE OF CONTENTS Precautions ....................................................................................................................................i Table of Contents/ Product Description .............................................................................................1 Features .......................................................................................................................................2 Controls/Connections..................................................................................................................3-5 Specifications.................................................................................................................................6 General Operation/Applications ...................................................................................................6-8 Service/Maintenance .....................................................................................................................9 Warranty Information.....................................................................................................................9 Congratulations on your purchase of the BBE BMAX-T Bass Guitar Pre-amp! The BBE BMAX-T is an extremely versatile pre-amp which is capable of achieving a wide array of tones while conveniently configuring itself into any application. No extra devices are needed to get flawless performance out of the BBE BMAX-T. The BMAX-T is a high quality tube bass preamp/processor with applications both in the recording studio and on the road in demanding live applications. At the heart of the BMAX-T is our class A, DC regulated tube preamp section, the design of which follows on in the tradition of the classic tube preamp designs of the 50's and 60's. It features a high voltage (300V) tube front end, providing all of the pre-amp gain and passive interactive tone control. The BBE Process--"What it Is" Loudspeakers have difficulty working with the electronic signals supplied by an amplifier. These difficulties cause such major phase and amplitude distortion that the sound reproduced by speaker differs significantly from the sound produced by the original source. In the past, these problems proved unsolvable and were thus delegated to a position of secondary importance in audio system design. However, phase and amplitude integrity is essential to accurate sound reproduction. Research shows that the information which the listener translates into the recognizable characteristics of a live performance are intimately tied into complex time and amplitude relationships between the fundamental and harmonic components of a given musical note or sound. These relationships define a sound's "sound". When these complex relationships pass through a speaker, the proper order is lost. The higher frequencies are delayed. A lower frequency may reach the listener's ear first or perhaps simultaneously with that of a higher frequency. 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. BBE Sound, Inc. 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 are differences among various speaker designs in the magnitude of their correction, the overall pattern of correction needed is remarkably consistent. The BBE Process is so unique that 42 patents have been awarded by the U.S. Patent Office. 1 BMAX-T FEATURES AND APPLICATIONS · The BMAX-T is perfect anywhere an extremely high-quality, pristine preamplifier is required for the bass guitar · It can be used in the recording studio where a bass amplifier is impractical due to space or loudness considerations · In performance applications, players will find the BMAX-T's ergonomics intuitive and easy to use · All players will find the BMAX-T's EQ and Dynamics controls, as well as our patented Sonic MaximizerTM Process, afford a wide palette of tonal experiences · Full Function BBE® Sonic MaximizerTM · All tube Class A front-end with interactive 3 band EQ and interactive "bright" switch · Hand-selected premium quality Groove Tubes® 12AX7 preamp tube · Jensen® JT-DB-E transformer balanced DI output · Optical "soft knee" compressor · Custom torroidial power supply transformer · Inputs for both passive pickup and active pickup instruments · 1meg ohm input impedance (Passive input), 100Kohm (Active input) · Ground lift switch · Balanced XLR and 1/4" unbalanced output · Mil-spec circuit boards · Extra thick, extra wide circuit board traces for unequaled electron flow · 1% metal film resistors throughout · Solid 1/4" thick aluminum extrusion front panel for extreme ruggedness IMPORTANT Before you begin, please check the contents within this box to insure that included are: 1. The BBE BMAX-T Bass Guitar Pre-amp. 2. The BBE BMAX-T User's manual. If either of these items are found to be missing, immediately contact the BBE dealer from whom the unit was purchased immediately. WARNING! To prevent possible speaker or amplifier damage, always power-up peripheral devices first, wait 10 seconds, and then turn on the power amplifier. Turn off power amplifier first, then power-down peripheral devices. 2 FRONT PANEL CONNECTIONS Input 1. PASSIVE: This jack allows for the connection of a bass guitar with passive-pickups to the BMAX-T. 2. ACTIVE: This jack allows for the connection of a bass guitar with active-pickups to the BMAX-T. It is attenuated, with respect to the "passive input", by about 6dB to allow for the higher level output of active-pickup systems. Pre-amp 3. BRIGHT: The Bright Switch connects a capacitor to the GAIN circuit creating a 10dB boost @ 10Khz. 4. GAIN: This controls the output of the preamp section post EQ. 5. 3-BAND INTERACTVE EQUALIZER: 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 circuit can be described as interacting, such that when all 3 tone controls are turned to 0 then no signal is passed at all. Para-mids 6. FREQ: A range from 250hz to 1000hz is adjustable with the FREQ knob. 7. GAIN: This control is adjustable as follows: "0" = -12dB "5" = 0dB "10" = +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". 9. 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-BMAX footswitch. BBE Process 10. LO CONTOUR: This control is a low frequency adjustment for the BBE Process. It provides a boost of 10dBu when turned to its maximum position (clockwise) at 50Hz. When turned to its minimum position (counter-clockwise) it would be flat or no change. 11. PROCESS: When the knob is in its minimum position, completely counterclockwise, no process is taking effect and the circuit is in its noise suppression mode. Turning the knob clockwise will introduce the BBE Process. Adjust the knob to mix the desired amount of process to suit your taste. Use the BBE as an extension of the tone controls. Generally a good place to start the BBE process is to set the knob to it's 12 o'clock position, then adjust accordingly. Note: The BBE process is applied after the effects return. 12. BBE IN/OUT: This switch engages the BBE Process as indicated by the green LED. When in the "OUT" position, the green LED will not illuminate, indicating that the BBE Process has been disengaged. This switch is superceded by the use of the optional FS-BMAX footswitch. Output 13. MASTER: This control simultaneously adjusts the signal level of both the Balanced and Unbalanced outputs. 14. POWER: This switch applies AC power to the BBE BMAX-T. The green power switch will illuminate when the power switch is in the "ON" position. 4 REAR PANEL CONNECTIONS 1. AC POWER CORD: This is a standard two-pronged AC power cable. 2. FUSE: Replace ONLY with same type Fastblow fuse. U.S., Canada & Japan models: .5A, 250VAC fast-blow type All others: .250A, 250VAC fast-blow type Footswitch 3. BBE: This jack allows remote in/out switching for the BBE Sonic Maximizer section of the BMAX-T. Please use our (optional) FS-BMAX dual footswitch. 4. COMP: This jack allows remote in/out switching for the COMP section of the BMAX-T. Please use our (optional) FS-BMAX dual footswitch. Ground lift 5. GROUND LIFT: In the "up" position, use this switch to disable the ground pin of the XLR connector. This is a useful feature in eliminating a ground loop between the BMAX-T and any subsequent component in the signal chain. Output 6. DI OUT: This is a transformer 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 BMAX-T Pre-amp to the next subsequent component in the system, i.e. power amplifier. Effects 8. RETURN: Use this jack to connect the BMAX-T to an effects processor's output. 9. SEND: Use this jack to connect the BMAX-T to an effects processor's input. The send jack can also be used to feed the input of a guitar tuner. 5 Specifications Frequency Response: ...........................15Hz ­ 30kHz +/-3dB Signal to Noise: ....................................100dB@unity THD: ................................................Tube section 1%, Post-Tube section 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) ..................15dB@ 6kHz Mid (cut only)...........................15dB@ 300Hz Bass (boost only) .....................15db@ 40Hz Bright Switch: ....................................+10dB@ 10kHz, 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 circuit can be described as interacting, such that the frequencies affected by each control is affected somewhat by the settings of the others.When all 3 tone controls are turned to 0 then no signal is passed at all. BBE's exclusive "PARA-MID" midrange equalization offers even further control over the crucial mid-band of the Bass' overall tonal characteristics. Compression is a feature that will be welcomed by any bass player. Adjust the LEVEL knob to eliminate any volume peaks. An increase in sustain is also a desired result of large amounts of compres ...