Webb Steel Guitar Operating Manual - page 6
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recognizing the options available on the Webb!]
If you do not need the EQUALIZER to modify/build your primary tone, you may choose to use it as a pre-set
option for another desired tone. Switch it "IN" or "OUT" as needed for the option of a desired pre-set tone. For
example, since you can make a major tone change with its EQ tone spectrum bands, you may wish to have it pre-
set to obtain the fat-heavy chord-sound of the great Curly Chalker. Or, if you want a cutting, crisp sound similar to
steel guitar legend Ralph Mooney, that too can be dialed in. Once it is pre-set, that sound becomes available
when you choose to flip the "IN" switch! You just need to take a little time and learn how you want to use the
EQUALIZER, a very useful and versatile tone-shaping tool.
SPEAKER:
All manufacturers select a speaker designed to match the wattage output of the amp they
accompany. Those speaker’s voice coils must be capable of handling the high temperatures created by
momentary output voltage surges. However, few speakers can take high volume for long periods of timea
situation that would lead to premature speaker blow-out/burn-out, even when the volume control is set at half (or
less) of its total range.
Webb recommends an 8-ohm speaker be employed with its amps. A 4-ohm speaker (or speaker system) can also
be used, but users should be aware that speakers with resistances of less than 8 ohms are more prone to
destruct because of the high (225) wattage output power provided by Webb’s power design. A speaker or speaker
system having less than 8 ohms of resistance does offer a bit more volume during general use. All Webb
amplifiers produced after 2006 were equipped with an 8-ohm, 15", Kappalite speaker, manufactured by the
Eminence Company. This speaker was found to mimic the response of the JBL speakers previously supplied with
Webb amps. [JBL ceased manufacturing amplifier speakers in about 2004.] The Kappalite speaker weighs 8
pounds; a weight appreciated when compared to a usual alnico-magnet amp speaker weighing over 20 pounds.
This speaker is front-loaded onto the amp’s ported metal baffle. These speakers use a neodymium magnet in
place of an alnico or ceramic magnet. A magnet made of neodymium material is the strongest permanent magnet.
[For information regarding these magnets, see
http://www.britannica.com/Ebchecked/topic/408837neodymium
.]
SPEAKER CHAMBER:
This innovative chamber, with its front and rear ports, isolates the speaker from the
amp chassis. The chamber is riveted and also bonded to the amp’s metal speaker baffle, which is securely
mounted to the cabinet’s sidewalls. The chamber has four, front-accessible ports bordering the speaker on the
baffle, as well as a 4" X 13" rear-accessible port. Six screws release the speaker grill for access to the baffle. If
one, some, or all of these ports are closed, the amp’s sound is altered incrementally. For example, covering the
rear port of the chamber, while opening any or all of the front ports, will project the speaker’s back-sounds
forward. This provides the ultimate in directional sound, gives additional volume and fullness to the output, and
prevents the escape and echoing of the amp's sound out the back, which is typical of open-back speaker
cabinets.
The amp is delivered with the rear port and the two top front ports covered. The two front-bottom ports have port
tubes in place and are otherwise open. This configuration significantly provides a greater bass presence to the
sound. If the user chooses to open the top two front ports, the bass presence is somewhat reduced. When the
back port is opened, the very common “room-filling” sound of open-back speaker cabinets is created.
Port Covers: Four, full-fitting port covers are supplied with each Webb amp, allowing the user to customize the
way the speaker projects its sound. Installing certain covers provides options for "personalizing" the tonal
characteristics of the amp's sound delivery chamber. Users are encouraged to experiment with the front ports to
determine the character of the sound delivered by the chamber. This could mean closing or keeping open one or
both of the upper two and/or closing or opening one or both of the bottom two ports. If all 5 ports are closed, the
result is the characteristic sound of an enclosed speaker cabinet. By opening the back port (whether any or all of
the front ports are opened or closed), the characteristic “room-filling” sound of most "open-back" amplifiers is
projected. The options of an adjustably ported and bottom "tubed" speaker chamber is Webb’s effort to support
users’ desire to obtain tonal "supremacy", an advantage which discriminating musicians seek but rarely find in
most amplification systems.
Port Tubes: The amp comes with acoustically designed tubes installed in the lower front ports. Testing revealed
little beneficial tonal change if the upper ports have similar tubes. The use of the tubes will emphasize the bass
overtones from the amp's speaker, regardless of what speaker is used. All users are encouraged to experiment
with these tubes as well as the port covers provided, either having both tubes inserted or just one (and with,