I thought I had finally narrowed down my search for a new head to the Ampeg PF500 or Hartke LH500 (I actually have my eye on a good deal for the Ampeg). However, I was continuing my browsing other brands and I came across a Carvin BX600. I have an Ampeg BA115 and I have played through an Ampeg PF500 on a 410 and it does sound sweet. The Carvin is older and the only reason that it is a consideration in my deliberations is because the first head that I had was a Carvin Pro Bass II and I actually love that sound. I only have one question regarding the two: Does anyone have any experience playing with a Carvin BX600? I would be paying the same for either one except that the Ampeg is a blem and the Carvin is used. I would like to hear from those of you who have played through a Carvin BX600 and tell me what you think. BTW - I have a GK 410MBX. Thanks!