I spent a couple of hours this weekend, testing a stock Grail and DF modified Plexi modules against the real things. I have a freind who has both a early Dual Rectifier (with matching recto 4x12) and DF modified Marshall head 2203 (through a vintage 1960 with 75watt Celestions. )
I was running the modules in a RM-4 through a 2502 poweramp and into a newer 1960B 4x12. Although there were extreme variables (6L6 tubes in the Recto and much larger Mesa cab (with Vintage 30 speakers) with the Recto head for just a couple), the Grail did a great job of re-producing that sound. I think the sound was 90% there. The main difference was the low end hump (thud) registering in different frequencies, but without a critical A/B, the difference is minimal. If the same cabinet and a 6L6 based poweramp was used, my guess is that it would have been 95% there.
Regarding the DF Plexi module vs., the DF 2203 head, the results were predictibly even closer. I would say the sound was 98% there. The 2203 had a slight brightness that the module could not replicate, even with the bright switch on - it was just a different tone. Also, adding presence on the power amp didn't really do it either. But, the sound was very, very close.
So, to me, it just proved that the modules, at least those two, really did what they are supposed to do. I have to say I was totally impressed with both modules. Any body else do any A/B testing?
I was running the modules in a RM-4 through a 2502 poweramp and into a newer 1960B 4x12. Although there were extreme variables (6L6 tubes in the Recto and much larger Mesa cab (with Vintage 30 speakers) with the Recto head for just a couple), the Grail did a great job of re-producing that sound. I think the sound was 90% there. The main difference was the low end hump (thud) registering in different frequencies, but without a critical A/B, the difference is minimal. If the same cabinet and a 6L6 based poweramp was used, my guess is that it would have been 95% there.
Regarding the DF Plexi module vs., the DF 2203 head, the results were predictibly even closer. I would say the sound was 98% there. The 2203 had a slight brightness that the module could not replicate, even with the bright switch on - it was just a different tone. Also, adding presence on the power amp didn't really do it either. But, the sound was very, very close.
So, to me, it just proved that the modules, at least those two, really did what they are supposed to do. I have to say I was totally impressed with both modules. Any body else do any A/B testing?