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When the TREBLE is set in its higher regions (2:00 – 5:30) the dominant character will be one of very bright, TREBLE-heavy fre-

quencies and the BASS and MID controls will seem less effective. Conversely, a very low setting on the
TREBLE will produce sounds that are perhaps a little BASS heavy and overly dark and the BASS and
MID will appear as the dominant controls. So you can see that setting the TREBLE with care and taste
in mind is critical for the Tone control string to work in harmony.

In all the Channels, the middle region of the TREBLE delivers the best balance and creates sounds that are plenty bright enough ,
yet still rich and warm. We suggest that you start with the TREBLE at 12:00 and adjust up or down slightly until the desired blend is
achieved. Remember that you can use the PRESENCE to add additional (and slightly higher) top end with no penalty in regards to
the effectiveness of the other Tone controls as the PRESENCE works in a part of the circuit that is much farther down the line in the
signal path and has no direct effect on the preamp controls.

NOTE: High settings of the TREBLE (2:30 – 5:30) can put extra stress on (even borderline) microphonic preamp tubes (ones that
are susceptible to high pitched ringing and noise) and cause them to begin ringing or show other signs of instability. Many tests were
run on the set of tubes that shipped in your amplifier to ensure they were stable at the time of construction. However, tubes are not
perfect devices–much like light bulbs–and can change over time and become more microphonic or increasingly unstable. Luckily you
can remedy most tube problems with a simple tube swap. Avoid these settings (especially in Combo amplifiers – where the added
sympathetic and vibrational forces put even more stress on the tubes) to ensure trouble free performance.

MID

The MID control acts much more like a standard tone control and doesn’t have quite the massive global shaping power of

the VOLUME and TREBLE controls, yet its setting does impart a strong character on the sound. It brings in and out a broad band of
midrange frequencies and along with these rides a fair amount of higher “low treble” range frequencies. These highs are lower than
that of the TREBLE or PRESENCE, but they are important for the punch and cut of the amplifier in a mix.

The middle region (10:00 – 1:00) is where the punch and attack begin to come on with more urgency and
this is where mahogany guitars really like to see the MID set for adding the cut and definition. Here the
top end begins to creep into the mix of the MID controls’ spectrum and chording sounds start to chime
and slash with a more forward and very present character.

From here on up (1:00 – 5:30) the MID introduces an aggressive range of sounds that are both full and quite forward as the dominant
frequencies become those present under control of the MID. In this range you will likely have to increase the BASS to add back in the
richness and warmth that gets overshadowed when the MID control is set high. If you like the attack and urgency found in this range
of the MID, all the other controls (except maybe the MASTER, which you may have to back down as the sound gets more forward)
may have to be set higher to keep up with the MID dominant curve. This is fine, although there will reach a point of diminishing return
as the headroom in the preamp gets eaten up by this tonal arms race and you begin to clip the preamp with the high signal from the
Tone control string.

For gain sounds in Channel 2 and 3 a similar story unfolds as the MID is increased. Lower settings (7:30 – 10:30) will produce wider
sounding, more elastic feeling chordal sounds and the single notes will have a more creamy, smooth character. High harmonics cre-
ated by the gain circuit and controlled largely with the TREBLE and PRESENCE will add a layer of three-dimensional haze on the
sound that smears nicely because the midrange is relatively scooped by this lower setting. As the MID is increased past this region,
more thick “gut punch” and low-Treble region attack creeps in and the sound becomes more forward.

NOTE: Channel 1’s MID control is of a higher than normal value to allow more punch and cut for Clean sounds. Because of this,
midrange settings (sounds) you may be used to on other amps, including MESA’s, may be found at lower settings here in Channel
1 of the JP-2C. The frequencies carried in the preamp are identical, there is just more amplitude (more mid) available. You might
think of it this way; if you are used to a MID setting of 11:00 on other amplifier’s Clean Channels or Modes, an equivalent setting may
be found here at 8:30. The entire range from what would be 0 to 10 on a “normal” MID control is spread across a tighter region here
and is available from 7:00 - 1:00 (0 to about 6.0 if there were numbers on the control).

80Hz

240

750

2200 6600

80Hz

240

750

2200 6600

GAIN

TREBLE

MASTER

PRESENCE