Guitarix team http://www.guitarix.org/
5 Pedalboards using it

GxJCM800pre

Plugin screenshot

Emulation of the classic Marshall JCM800 preamp (*) (*) 'Other product names modeled in this software are trademarks of their respective companies that do not endorse and are not associated or affiliated with MOD. Marshall JCM 800 is a trademark or trade name of another manufacturer and was used merely to identify the product whose sound was reviewed in the creation of this product. All other trademarks are the property of their respective holders.'

Control Default Min Max
Pre Amp 0.50 0.00 1.00
Middle 0.50 0.00 1.00
Bass 0.50 0.00 1.00
Treble 0.50 0.00 1.00
Presence 50.00 0.00 100.00
Master Volume 0.00 -20.00 20.00
http://guitarix.sourceforge.net/plugins/gx_jcm800pre_#_jcm800pre_ v.1:28.3-9