Heavy Hitters 1 has a 4x12 Recto cab in it.
I agree, I prefer bright tones myself. Most of the commercial IR mixes sound rather dark to me, but I think that's the trend with modern productions, I rarely hear bright high gain tones that were common in the 80s and 90s. Considering that IRs in general seem to be marketed for mixing rather than simply playing by yourself, it makes sense.
In any case, since you have Heavy Hitters 1, just got to the 4x12 Recto cab with a V30 speaker, go in the mic section, make sure to select the MPT IRs (so that you can blend 2 or more IRs without any phase issues), and try a single 57 mic or a blend with 57 and 121. Try the Fredman technique 57 too (they'll also have them pre-mixed in the Mix folder). Be sure to read the included .pdf manual, it explains what everything in the pack is. In general, you want your IR to sound as close to the finished tone as you can. So if you used a bright amp, for example, with treble and presence cranked, and the tone it still dull, change the IR to something brighter, don't try to EQ the tone (though it can work sometimes). EQ is a very crude an primitive tool, it's hugely useful, but it can only affect the sound so much, use it for small adjustments only, if you find yourself doing crazy adjustments and the tone is still not right, just change the IR.
As far as dealing with the low end, first of all, there's always the good old 808 before the amp. You can also use a 10 band graphic EQ, start cutting from 250hz and downward in a diagonal kind of way (cut 2db at 250, 3db at 125, 4db at 62.5, and so on). You can also try boosting from 1 or 2 khz and upwards in the same fashion to accentuate the pick attack. You can also try your luck with a tilt EQ before the amp.
Then, there's the IR block, make sure to use the low and high cuts, personally I cut lows at around 80hz and highs at around 10khz. Finally, use an EQ before (or after, doesn't really matter, but if you're using stereo IR configuration, it makes more sense to throw a mono EQ right after the amp) the IR. Parametric, high shelf, and tilt all are very useful, you can use more than one too to get the desired effect. For the parametric EQ, try the low band at 120-200hz, play with the Q (0.2-0.7) and cut 1.5-3db. And easy way to brighten the sound it to use a high shelf at around 4-5khz, then just boost that range to taste. Tilt can work too, but it's kind of a one trick pony, it might work, but it might not quite give you the result that you want. Be careful with the high cut and low cut in the parametric EQ, they have a pretty steep roll off as compared to the high and low cut in the IR block (in the parametric EQ, the high cut is noticeable if you set it at 20khz, that's a pretty massive roll off).
Obviously, there's also the amp. Recto is flubby as all hell, that's just how Rectos are. Fireball also has tons of bass, and Mark IV can be hard to dial in. With the rest of the high gain amps, make sure to pay extra attention to the balance between bass and resonance. Power amp saturation will affect the bass response as well, Bias and Bias X will also have an effect if you have some power amp saturation going on (for high gain, you don't want a lot of it, try using it sparingly as a tool to smooth out the high end and bring in some extra mids). Don't be afraid of cranking the treble and presence, with some amps you can crank them really high without any ice picky harshness, others - not so much, and of course it all plays together with the power amp - when you're cranking treble, you're increasing the volume of the high frequencies, which will make the power amp saturate those frequencies more if the power amp is cranked high enough, and if the power amp is cranked high enough, it will squash and distort excessive high frequencies instead of amplifying the linearly like an EQ. The Friedman amp is a good example - the default master setting is really high and it makes the amp sound rather dark. Dial the master way down to 3 or 2, and it brighten up considerably. If you then tinker with the controls (try the saturate setting on, and everything else off), it can be dialed really bright.
