Clean Channel version of JFET based Amp Emulators?

[YouAre]

We all know and love the FET amp emulators (BSIAB, English Channel, Prof Tweed, etc...) for their gainy sounds, but what if we want the cleaner sounds their respective amps produced?

I'm probably planning too far ahead here (who doesn't on this board?) but I want to build a little amp using the tiny giant, with one of the ROG or other fet based amp simulators as a preamp. I think it'd be nice/nifty to be able to switch to a cleaner sound.

How would you guys go about this? First thing that comes to mind for me is to increase the source resistance or mess with the bypass cap of the source resistance to lower the gain. Alternatively, you could remove a gain stage. My bet is that the smart move would be a combination of both. Of course bias would be re-adjusted for the decrease in current through the FET caused by adjusting the source resistance.

What say you?

Thanks again!

[Quackzed]

theres a 'fet2-b' project thats basically a clean jfet sim of a blackface fender twin/showman that would fit the bill. however most jfet sims offer a bit of distortion. if they didn't, you wouldn't hear 'em working... i mean, clean is clean. nada. so really, you'd be talking eq/tonestack for changing the tone. without the clipping, you've got a linear boosted/cut result. no change in effect.
now if you want a bit of overdrive etc... then you suddenly can hear the effect of jfets vs. trannies/opamps etc...
so there arent alot of jfet sims that do clean, due to the 'already clean' nature of a guitar signal...
its a bit like taking orange juice and adding a bunch of other ingredients to make it taste like orange juice...

[YouAre]

I certainly understand what you mean.

I should (re)define what I mean by "clean." I mean a less gainy/distorted sound out of the preamp, without simply dialing back the gain. As in what you'd get from the clean channel of any of the aforementioned amps.

I was thinking since we're overdriving the fets to get distortion, what if we pulled them back from clipping so that we get simple coloration from them? Logically to me, that seems like it'd make for a nice preamp for an amp.


Also, would you happen to have a link to the FET2-B?

Thank you.

[Quackzed]

fet 2-b
http://www.diystompboxes.com/smfforum/index.php?topic=73173.0
and that makes alot of sense really. you often just want a bit of 'rounding' or compression and a bit of overdrive without a big change in tone... makes perfect sense.
imho a single jfet stage or a mini-booster/srpp stage can be pretty subtle and good sounding cleanish options. they both offer a bit of clean -plus- type tones... that is a bit of overdrive character when you push em...
just keep in mind that whatever they get fed into needs to have enough headroom to allow them to stay clean as well.
there are quite a few single transistor boosters that do that type of thing...
sparkle boost, stratoblaster, mini-booster, the beginner project, not all jfet emulations, but still...
i like the mini booster myself... just a bit of compression/od barely. but feels a little ampy.
maybee a minibooster/fender tonestack/minibooster type thing could be pretty versitile
http://www.muzique.com/amz/mini.htm
http://www.google.com/imgres?q=fender+tone+stack&um=1&hl=en&sa=N&tbm=isch&tbnid=1NAb1jaOv-tHYM:&imgrefurl=http://www.ampbooks.com/home/classic-circuits/bassman-summary/&docid=cgufCsxspSOFTM&w=292&h=241&ei=mT1bTr2mEtPqgQeRxviXDA&zoom=1&iact=hc&vpx=336&vpy=203&dur=2281&hovh=192&hovw=233&tx=132&ty=87&page=1&tbnh=145&tbnw=176&start=0&ndsp=8&ved=1t:429,r:5,s:0&biw=1024&bih=567