RockaRoller89
So I am starting to like the sound of BOSS SD1 over DS1. Or perhaps I was wrong on what the sound of distortion is, What's the difference between Overdrive and Distortion ?
Scale really and tone really. Distortions distort more and compress more, though some distortions can work well at lower gain settings. The Rat being one example, and an SD-1 with its gain set high produces quite a lot of distortion. Another way of looking at it is that overdrives are intended to hit an amp with a higher input signal to push it into distortion plus add some clipping of their own as well. Good overdrives usually "clean up" by reducing the guitar volume, distortions not so much.
Many overdrives also produce a mid boost to increase focus so soloing/lead work will cut through a mix, the Tubescreamer being a good example. The SD-1 also adds a mid boost, but it's a bit less pronounced. Distortions often have a scooped mid, the Big Muff being an example. Some guitarists use overdrives with the pedal volume set high and the pedal gain low or even off altogether, using the pedal's compression and mid boost to push their amp.
RockaRoller89
I have BOSS DS1 any suggestions on how I could get more of a SD1 tone with it instead of distortion.?
Try turning the gain down. Though the two pedals are different even though both use diodes to generate the cliping. The SD-1 produces asymmetric distortion where the two halves of the wave-form are clipped to differing amounts, which is closer to how valves behave than symmetric distortion. The Sd-1 is also less bright and more mid heavy.
RockaRoller89
Now I know VST vs real pedal would and could be different but what do you guys think ?
No "would" or "could", they are very different. Having tried the SD-1 emulation in Amplitube and the similar effect in Guitar Rig and TH2 they sound, respond and feel completely different to the real thing. Vintage fuzz emulations, especially of the Fuzz Face are even worse. To get anywhere close to the response and tone changes you get from the real thing simply by turning the guitar's volume pot out of an emulator requires considerable eq-ing and fiddling with the gain levels throughout the software rig.
The easiest way to get the SD-1 sound is to get an SD-1. They're an absolute bargain pedal. The design is essentially the same circuit as the Tube Screamer but with assymetric clipping, flatter tonal response, a better bypass buffer and they cost about a third of the Ibanez or Maxon Screamers. If you use humbuckers the SD-1 might be a bit mid heavy, though not so much a s a Screamer. Desoldering the capacitor marked, if I remember correctly, C6 on the board can open them up quite a lot. And if you don't like the result, just put the capacitor back.