rat variants

[JIG]

What's the difference between them all? I have seen this site:

http://happybob.com/rstrand/rat/rat_versions.htm

which does a fair job but doens't explain it all.

I just got a Turbo Rat and tried it into my silverface Champ along side my FX50 (which is supposed to be the DOD 250 OD/pre) and they sound pretty similar to me. Maybe I just like to dial in a certian tone.

The Turbo rat is set like this
Dist- 12:30, Filter 10, Vol 10:30

DOD FX50 Vol- 12:00 - 1:00
Dist: maxed.

I did swap out the chip in the FX50 for a 4558.

I have found that the distortion on the Turbo Rat gets pretty farty/ muddy when turned past 2:00. It could be due to sag from the tube rectifier in the Champ.

Running the FX50 into the Turbo Rat adds some cool intensity that I like.

My biggest question is which modern Rat is true to the original Rat cicuit? And how does the Rat 2 differ? Is the Vintage Rat REALLY  the original circuit?

I know the Turbo Rat uses LED's for the clipping diodes. I opened it up and played a bit watching the Led's light up. Pretty cool! Does using Led's as opposed to silicon diodes account for the doubled output of 2.8v as opposed to the 1.2v in the other Rat versions? All I know is that the Turbo Rat hits the front end the the Champ VERY hard! I would like to try another Rat to see the difference.

TIA,

JIG

[dominatrix_volleyball]

I don't have much to offer... except for the name: LM308.

That's all I got. It's what the original Rat used and is <supposed> to be a pretty big deciding factor in the differences between Rat models. If you know how to find similar opamps (I don't), you should totally experiment...

But you probably already knew that.  :oops: