Based on the MESA/Boogie® Bass 400+
500 Watts @ 2Ohms, All Tube, Class A/B Power / 12x6L6, 4x12AX7
Pull Shift Bass, Treble Controls (Standard Mid Control)
Volume 1 offer a high headroom preamp that you might find preferable for active type basses. The gain is slightly lower than Channel 2 and the tonal personality is slightly different. The Pull Bright switch built into Volume 1 can be great for funk bass, as it accentuates the harmonics above the Treble control region.
Input 2 and Volume 2 recreate the classic sounds of the D-180, The gain is slightly higher and may be better suited for traditional basses than Channel One. But be certain to sample both channels because their tonal personalities are both very usable with very interesting differences. It is even possible to preset the two channels
uses traditional type tone controls which have been especially tailoredfor bass, and whose ranges can be extended by use of the “Pull Shift” switches. The Treeble control, when set high, becomes the most powerful of the three. At settings of 7and above it will minimize the effect of the Bass and Middle, but they will become the stronger controls when the Treble is below 5. Most players find a “sweet spot” between 2 and 5 where the tonal balance is just right for them. Pulling out the Treble Shift alters its frequency center point downward, toward the upper mid range. (And since there is more musical energy at these frequencies, your amp will seem to get a little louder as well.)
Using either Bright switch injects an extra dose of high treble. The Bass control is wide ranging and using the Pull Shift can boost its power. Your Bass when used with our speaker cabinets) can produce more true fundamental tone than just about anything else. Its bottom end response is truly “profound” and yet it avoids boominess and muddiness. The Middle control is the subtlest of the three. Its purpose is filling the gap between the treble and bass frequencies. Spice according to your liking.
Full undistorted power is developed at settings around 5. There is rarely any reason to run the Master above 6 or 7, as higher settings merely increase noise without improving power or tone.