Operation Manual

670| Effects for the Sounds

AMP (Ampliﬁer)

Pa4X includes accurate guitar and bass ampliﬁer and cabinet modeling.

Some of the effects combine an ampliﬁer and a cabinet model.

Modelling ampliﬁers

Pa4X comes with a wide selection of the best amps, that offer the widest

possible array of great tones. The operating mode of the preamp and power

amp, the response of the tone controls, and their placement within the cir-

cuit will change depending on the type of amp you select, precisely replicat-

ing the exact gain and tonal character of the original amp. The all-impor-

tant power amp stage (class A or AB) and negative-feedback circuit (or lack

thereof) are also carefully simulated.

The volume controls

Two main controls affect the volume (or gain) and at the same time the tone

of the amp: Drive Gain (controlling the preamp gain and the amount of pre-

amp distortion) and Volume (controlling the preamp output level). Each con-

trol has its own speciﬁc job, and the sound of a particular amp model can

vary over a very wide range just depending on the settings of these controls.

In addition, the Cabinet Trim control (a power attenuator) is placed between

the output of your amp and the input of your speaker cabinet. At the end of

the signal path, the Wet/Dry parameter in the FX Edit page, and the Master

knob in the Mixer/Tuning > FX Send page, control the level of the ﬁnal mix

and allows you to balance all your presets to each other.

We have made the relationship between preamp and power amp work in the

same way as in the original amps. Therefore, to obtain truly authentic tones,

please use the Pre/Drive Gain parameter to control the preamp distortion,

and the Volume parameter to control the distinctive distortion and warmth

of the power amp stage.

Be advised that setting the Drive Gain too high will result in heavy distortion,

and is not recommended.

Tube talk

‘Tubes’ is the name adopted in the USA, while ‘valves’ is the British equiva-

lent. As all the amps we’ve modelled come from one of the two countries just

mentioned, we will use the corresponding term in the following descriptions.

Also, please note that an ECC83 preamp valve is the British version of a

12AX7 preamp tube used in the USA.