SWR Bass Combo Amplifier Owner's Manual page 16

3AG, 10 amp, fast-blo. Do not defeat the purpose of this feature by using a higher rated fuse as it can
damage your amplifier and void your warranty.
The fuse can open as a result of a fault in the speaker cable, the speakers themselves, or the power amp
being sent well into clipping. With this in mind, it is wise to carry extra fuses at all times.
LINE FUSE (A/C OR MAINS FUSE)
This fuse is provided to protect the internal electronics against power surges, etc. It also protects the unit
against itself should one of the internal components fail. If this fuse should open, replace it with the same
type of fuse and rating. Do not defeat the purpose of this feature by using a higher rated fuse as it can void
your warranty.
Proper size of the AC fuse for all countries is 3AG. Proper rating of the fuse is as follows:
United States: 7 amp slo-blo
Japan: 8 amp slo-blo
Europe (230V-240V): 4 amp slo-blo
A/C CORD RECEPTACLE
This receptacle accepts a standard A/C power cable (supplied with the Black Beauty in the United States)
used with almost all current musical, professional and household electronic devices. We recommend great
care when packing up. If your unit is not in a rack case, put the cable in your instrument or accessory case or
leave it attached and looped around one of the rack handles. If it does become misplaced, a replacement
cable can be purchased at almost any music or computer store.
NOTE: The rating for this cable is 3 conductor, 10 amperes minimum. Look for this rating on the cable.
Make sure the cable is plugged in all the way in both the amp and the wall socket.
REMOVABLE CASTER WHEELS
Your Black Beauty comes with a set of four, heavy-duty, removable caster wheels. SWR uses only closed shaft
sockets so as to prevent air leaks or unwanted noise when the enclosure is in use. To install the caster
wheels on your Black Beauty, carefully turn the unit upside down (or on its side) so that the caster
base/sockets are visible. Insert the shaft of each caster wheel into a socket on the underside of the Black
Beauty. When all four wheels are firmly in place, return the Black Beauty to its upright position and you're
ready to roll. You can leave the casters in place during performance, but it's recommended that they be
removed so as to allow the Black Beauty's speaker compartment to couple to the floor, which can be helpful
in extending its bass response. Please note that the ball bearing type caster wheels provided with your Black
Beauty may require periodic replacement depending on usage and care. Replacement caster wheels can be
purchased from the SWR Service Department.
INTERNAL FEATURE: VACUUM TUBE (VALVE)
SWR installs a specially selected 12AX7A dual triode on the preamp circuitboard of every Black Beauty. If this
tube needs replacing, we recommend that you replace it with a similar high quality product. This tube will
need replacing only if it becomes noisy or microphonic (which sounds like glass tinkling in the background of
certain notes), or completely fails (causing no signal or signal at very low levels). The tube in your Black
Beauty should last one to three years, depending on usage.
FINAL ENGINEERING SUMMARY
The two preamp gain stages utilize a specially-selected 12AX7A. The tone controls incorporate I.C.'s, and the
power amp is designed with extremely high quality bi-polar devices. Each type of device was chosen for its
performance and reliability in the application used. All primary electrical components are U.L. approved, and
SWR uses Beldon Cable for all shielded wire. All units are assembled by hand and individually soundtested in
the U.S.A. at our factory in Southern California.
14 • BLACK BEAUTY OWNER'S MANUAL