Re: sdotd bogner red
I personally prefer the Red. I think it's the most versatile, but the Uberschall and Blue definitely have their place. For high gain, the Red and Uberschall are completely different flavors - the Red is pure hot rodded Marshall pushed balls to the wall, while the Uberschall is more modern metal orientated, and nothing else really sounds like an Uberschall - it's not a Marshall sound, its not a Peavey sound, its' not a Mesa sound - it's an Uberschall.
The Uberschall's gain isn't overly aggressive or grainy, but rather smooth, so while the pedal just has gobs and gobs of gain, it is really easy to hear "not enough gain" and want to max out the gain control - a lot of people were disappointed thinking the Uberschall would sound like it has more gain, but I think it has plenty; I get the feeling that those are the people that think a 6505+ doesn't have enough gain on tap. I select the gain level by just listening to how loud the extraneous noise is. Once I find the spot that I consider too much noise, I back the gain ever so slightly off, and it is enough gain. It also helps to turn your amp up real loud, along with the treble. The Uberschall is great for slightly scooping the mids, but the midrange control really only cuts around 800 Hz-1K Hz, while the treble control can pass on the upper mid frequencies around 2K Hz, so you can get a usable scooped tone for rhythm guitars as long as you don't go overboard with it. It is also really easy to get a mid-heavy tone with the pedal; with all of the controls at noon, it is pretty honky, and you can get a cocked wah sound by just having the mid control near 10. The mid control is definitely the most sensitive control on the pedal. Overall, the gain character is dry, and I love it for rhythm guitars. Usually I'll record something with one guitar using the Uberschall for gain, and mix it with another guitar recorded using the Red for gain and both go to the bass channel on a Bassman 70, usually with either a flanger or chorus between the Bogner and the amp - the Uberschall getting a "jet-plane" flanger setting while the Red gets a "chorus like" flanger setting.
The Red is a sound we've all heard. It is the heavy metal Marshall sound. Screaming For Vengeance/Defenders of the Faith era Priest, '90s Alice in Chains (I'd say the Uberschall pedal describes the modern Alice in Chains sound more - they did use an actual Uberschall a lot on Black Gives Way To Blue after all, but Jerry always used all types of amps in the studio: AC30s, Shivas, XTC's, Ubers, JCM800, 5150s, Dual Rectifiers, etc.), Randy Rhoads, Mercyful Fate, the Scorpions, Iron Maiden, Candlemass, Slayer, etc. The Red will do any high gain Marshall sounds with ease. You can't really scoop the mids with it - it gets hollow sounding real quick. The gain has a pleasant graininess to it - not like a fuzz, but like a very aggressive gain character with a lot more presence than the Uberschall.
The Blue is my least used - but it still has its places. I'm sure it'll receive plenty of use on the next song I'm recording. The Blue excels at low to mid gain - trying to get high gain out of it is just an uphill battle; the most gain you'll get out of it is the overdrive on Thin Lizzy's Live and Dangerous. You can treat the Blue like an older Marshall, and put a treble boost in front of it, which worked great trying to get an early Mercyful Fate sound out of it. The Blue also is great for early Motorhead, really early Judas Priest (like Sad Wings of Destiny or Sin After Sin), Led Zeppelin, Deep Purple, early Black Sabbath, etc. The Blue is also great at cleaning up depending on picking dynamics and rolling down the volume control. The gain character is pretty similar to the Red's but a tad less aggressive. It fits songs where the Red would be too tight and seem like too much.
All of them come with a very useful boost function. I usually keep the volume between 6-7, and the boost mini-pots for volume and gain at "10" and "0" respectively. This will give a very noticeable volume boost for solos, while not adding too much gain - because there's usually enough already. In fact, the Uberschall only has a volume mini-pot and not a gain mini-pot, so you don't go overboard with the gain.
I've tried them all into a modified Bassman 70 (added option of switching between stock negative feedback loop, no negative feedback, and a presence control; also slightly modified tonestacks to leave just a bit more mids in the sound) and a heavily modified Vox Night Train 15 (1st gen - too many mods to list). I don't like the pedals on the Vox - it doesn't have enough headroom in the preamp; that amp just sounds better being overdriven by itself, and then being pushed over the edge with either a fuzz or treble booster. However, the Bogner pedals excel on the Fender Bassman. The Bassman has become my main amp thanks to these pedals. I personally use them more on the bass channel, as I think the normal channel gets too bright/too scooped a bit easily when overdriven. The great part is that you can just use a line switcher to switch between the normal channel for Fender cleans and to the Bogners/bass channel for dirt. I haven't tried them on something like an AC30, but I personally think an AC30 is best left sounding like itself in all of its glory, using treble boosters/fuzzes/OD for high gain (besides, AC30s get pushed into overdrive really easily). These pedals need a pure crystal clean amp to work best, preferably something with a versatile tone stack. I think Bassmans are the perfect amp for these pedals, because you have both the bass and normal channels to experiment with - two very different tone stacks with different gain stages.