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SoftAmp PSA
Win32 Win64    VST
VST rate
4.8 / 5
(8 votes)

SoftAmp PSA - Guitar pre-amp
SoftAmp PSA is a virtual-analog guitar pre-amp supplemented with noise gate and compressor, all modeled after famous guitar gear that needs no introduction.

At its core there are 5 distortion stages. First three are based on op-amps with zener diodes in the feedback chain, while the last two are just op-amps being overdriven into saturation. They are followed by tonestack, speaker simulator and an output level control. Each overdrive stage has a distinct frequency shaping quality according to their names. See the EQ plot in the bottom right corner for details.

All stages are modeled as nonlinear filters with their outputs depending on both the frequency and the amplitude of the input signal. It gives the most accurate digital representation, compared to cascaded filter/static waveshaper approach.

In addition to the basic controls, there are two more knobs that control the speaker simulator parameters - Shape and Rolloff. With both knobs at 0, the speaker simulator is completely bypassed (for example, to be used with external impulse loader).

Giving even finer control over the gain structure, there are two more buttons - Asymmetric and Soft-Clip. The former applies to the zener diode stages and replaces the default 4.7v/4.7v zener pair with intentionally unbalanced 3.3v/4.7v pair to saturate the signal with even harmonics. The more the first three stages are overdriven, the more pronounced is the effect. See the clipping LED indicators to have a feel of which stage gets the most saturation from the signal. The Soft-Clip function applies to the two overdriven op-amps and changes their open-loop gain from 1 million to just 200. This effectively makes the transition from linear to saturated region much more softer, making the distortion less harsh and also helping the fading notes sound smoother.

The PSI Denoiser noise gate has a handy "Learn" function. Don't play anything on your guitar and hit the Learn button. As soon as the LED goes off, the gate threshold would be automatically set to your noise level. The noise gate is applied directly to the input signal.

The Squeezo Range compressor is applied to the signal right before entering the PSA pre-amp. It's a very nonlinear, but musical sounding device. It acts as both upward and downward compressor depending on the gain and bias setting. In the original device those controls were not available for user adjustment.

(2.5 Mb)
  V 1.0
(2.6 Mb)
  V 1.0


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Feb 22 2018
  Benny Black
  ?  / 5
This VST is very useful.. U can get very fat heavy overdrivin sounds and the clean sound is pretty good as well. Really nice layout too .. great job !!

Mar 11 2017
  5  / 5
Thanks * * * * * (can I add 6th star? :)
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Jan 28 2017
  Robinson C G
  5  / 5
Really good and a excellent job!

Dec 25 2016
  Baron F.
  ?  / 5
Very capable thing. A lot of good sounds may be tweaked after learning how it works. Buzz and Punch knobs do a great job.

Dec 17 2016
  5  / 5
The range of sounds that this thing is capable of is simply staggering. Be it clean or driven this plugin is serving up all I'm after and so much more besides. Without a doubt this is now my first choice guitar amp VST. Top work AXP this is an amazing plugin.

Dec 10 2016
  ?  / 5
PLEASE make a VST Preamp based on the Yamaha DG 1000 ..
Dec 12 2016
..or a VST based on the old Tom Scholz Rockman Rockmodules, the Sustainor for example.

Dec 09 2016
  5  / 5
You're making incredibly great plugins! I like all of them, especially the tube simulations. This one is a little bit trickier than some others, on the other hand with a lot more sonic possibilites. In fact more or less everything you need in one small package. Fantastic! 10 out of 5 stars!!!

Dec 06 2016
  5  / 5
Отличный плаг!

Dec 05 2016
  3  / 5
Very, very nice plugin. Thanks

Dec 04 2016
  Viper ITB
  5  / 5
Fantastic plugin. Thank you!