Guys, Here are the parameters I think are most important for dialing in good tone on all of the Atomic products. For dialing good tones, here are the parameters that I think make the biggest impact. EQ BLOCK-In my mind this is the most important tone parameter. This EQ is called PRE TONE on the AmpliFirebox and PRE on the AF3, AF6 and AF12. The parameter is called ROLLOFF on the AmpliFirebox and LOWCUT on the AF3, AF6 and AF12. This is a HPF (High Pass Filter) that rolls off low frequencies BEFORE the amp model. This helps every amp model to sound more defined. A good starting point for this value is 250Hz. This means ALL frequencies below 250Hz will be rolled off. If you feel this takes away too much of your low mids can lower this value. You probably shouldn’t set this any lower than 125Hz. On the AmpliFirebox the EQ block needs to be ON and the PRETONE needs to be ON. On the AF3, AF6 and AF12 the PRE block needs to be active. AMP BLOCK-DAMPING-Every amp model reacts differently to this parameter. Try hard left, Center and hard right. You'll quickly get a feel for what sounds best with that amps model. With higher DAMPING levels you'll need to boost the LEVEL parameter. With lower DAMPING levels you'll need to lower the LEVEL parameter. (Note that the Rumble, Rumble Brite and Top Boost amp models are not affected by this parameter.) CAB BLOCK-Obviously the IR you load will make a HUGE impact on the tone. But the ROLLOFF parameter is very important. The best results come with settings between 7kHz and 10kHz. This is the best way to dial out the high frequency fizz that some people complain about. The PEAKING parameter is also very important. For darker sounds set to.70. For brighter sounds set it to 1.00. For any amp model that sounds too bright to you, set this all the way down to .50. KNOBS-MASTER-Different amp models react differently. Some I set far right, but never less than a center setting. This drives the power section of the amp model. On a clean amp, this can be the difference between crystal clean and breaking up. KNOBS-GAIN-Even for clean amps I set this at least to 3 or 4. You need enough input signal to get a strong tone, but too high and it breaks up. For high gain tones I find it sounds fuller and heavier at about 2 O'Clock as opposed to cranking it up all the way. With some amps I bring the gain down a bit and drive it with the SCREAMER or OVERDRIVE boost. The Recto is an example of an amp that works better this way. LEVEL MATCHING-Anytime you boost anything (EQ frequency, Echo Level, Boost Post Level) you're boosting the output level of the preset which can clip the output and cause distortion. Try to keep most effect block levels at 0dB or less. In the AMP BLOCK use the LEVEL parameter to try and match your different preset levels. If you find that you're clipping the outputs, lower AMP BLOCK LEVEL as much as you need to until the CLIP warning goes away. Lower your other presets AMP BLOCK LEVELS as well to match levels from preset to preset.