Re: OD808 TS7/9 OR SD-1?
Subtle difference between those pedals.
I have a TS808 and an MXR Classic Overdrive (kinda like in between an SD-1 and a TS808 but with a bit of its own thing going on), and I used to own a Maxon OD-9. Depends on what your tastes are and what you're going for. I prefer the Maxon/Ibanez family of overdrives for boosting high-gain amps for their familar sound. I personally preferred the TS808 because it's a wee-bit smoother than the OD-9, but the difference is VERY subtle once you drop tons of gain from the amp on top.
The OD-808 ought to be a tad more transparent and open-sounding than the TS808 (meaning it cuts a tiny bit less highs and lows), and the TS7 and TS9 are pretty much interchangeable. They are the same circuit, but the TS9 is made a bit better, so I ought to hold up to abuse a tiny bit better, theoretically speaking. The TS9 is a touch more aggressive in the high mids, and it is a wee-bit more compressed or gainy than the TS808, IME. Subtly. They all both do the Tube Screamer squishy creamy mids, smooth top, and tight lows thing.
The Boss SD-1 is close in the sense that it chops off and tightens the low-end and adds a hint of compression. The SD-1 has less creamy mids, and it sounds a bit more aggressive in the high-mids and highs, and its character is more grainy. I wouldn't say it's interchangeable with a Tube Screamer, but it's definitely within the same family. It can be moded to sound more TS-like easily too.
The Maxon OD-808 is the safest bet from those, I think.
The Electro Harmonix Easty River Drive also does the Tube Screamer thing too for cheap. A buddy has one and we've AB'd it with my Ibanez, MXR, and former Maxon. It's closer to the Ibanez than the MXR is for sure. It's a bit more open-sounding with a touch less gain. It's got less output level too, though.
