Alright, all you tech-oriented people out there, I need some guidence and suggestions. This would pertain primarily to 2000s heads, but should apply to the original 1200s, as well as all the 60 watt amp varients as long as they had the "contour" knob and switch. This is a multi-level question, so here we go... With practically all of the classic Sunn tube heads I've played through(Sorado, 200s, Sceptre, 2000s)I've noticed that, with varying degree, while fiddling with the tone controls, the appearant change on either "treble" or "bass" is not very gradual or "linear"(this term not in the strict audio sense). Now, I realize that these tone contols are passive roll-off; but still, for example, turning the bass from "1" to about "5" or "6" brings about an increase of low frequency tonality, but there's hardly any perceived change from "6" on up to "10". Additionally, the "bass" increase doesn't seem to real kick in until about "3". Is this lack of a smooth taper of tone due to the type/resistance of pots used, or capacitor value. Anybody have any tricks they have used to turbo-boost the EQ potential? Now, granted, the 2000s of course has the bass boost switch, but I hate to leave that on all the time(doesn't that eat up pre-distortion headroom when pushing the volume?)in order to get some "oomph" out of the rig(the head is going into a 2000s cab with EV 15's--I just prefer them to JBL's). Treble has never been a problem. Concerning the "contour" knob, I realize that it is a primitive mid-range control. Does going from "1" to "10" change the EQ curve from "smiley" to "frown"(or vice-versa)or is the circuitry not that sophisticated? It seems that the overall midrange emphasis, whether on 1 or 10, could be improved; like the intensity could be increased---is there any playing around with capacitor values that could accomplish this? One tech who worked on the head improved it(the mid-range) a bit, but at the expense of the bass response--I then had him change it back. He explained that the "contour" was on a separate side chain-like circuit, but still interacted with the "bass" enhance circuit when cap values were changed. What's up with all that? Can any of you explain it in basic terms, and what could be done about the "interaction" so that the contour effect can be goosed a bit, and I can get a more gradual and smooth change in the other tone controls as I roll the knobs. I realize some of you may be "anti-mods", but surely there can be some component improvement/substitution without the wholesale butchering I'm sure you've seen on the insides of old Marshall heads. Discuss amongst yourselves, and please don't tell me to just get an old SVT; Sunn rules---plus a 2000s head still doesn't weigh as much!!!!