I have an Ampeg SVT3-Pro working with a SWR Henry the 8x8. I just need a little more volume. I have an MXR di+ pedal that I use for a little more oomph, but I really want to keep my tone. Should I invest in a higher end pre-amp/DI like a SansAmp, or something else? I know other people have had problems with the Ampeg SVT3-Pro not pumping enough sound, but what is the best way to attack this? Thanks!