I spent some time last night when I should have been sleeping researching the history of Rats and I came to a similar conclusion. To contact the forum owner hit the Contact Us link. The clipped waveform will be affected by the low pass filter, as shown above, creating a shark fin shape as the tone control is maxed. If the signal to be amplified is too fast high frequencies , the op-amp will not be able to perform properly, only amplifying signals below the slew rate limit. The Power Supply stage provides 9V for the active circuits op-amp and transistor.
Our sincere appreciation to M. Trademarks, brand names and logos are the property of their respective owners. It sounds smoother, fatter, bassier and the dynamic response of the pedal is just awesome. This is how guys like Jeff Beck got such a killer sound out of one. The distortion stage is followed by a passive 'reverse' tone filter and volume control. The usual guitar center guy keeps its output volume low and dimes the gain control which is seriously crap.
The Gear Page is run by musicians for musicians. When the voltage difference positive or negative between the op-amp output and ground is bigger than the diodes forward voltage V F, the diode will turn on. The Clipping Amplifier is the core of the circuit, it is made of a non-inverting op-amp amplifier with variable voltage gain and some filters to shape the distortion response. It looks like I prefer my stock Reissue. All the interesting guitar signal will pass through, only harmonics below 7. Among the most famous are Kurt Cobain Nirvana , Jeff Beck, Radiohead et Sonic Youth guitarists or Graham Coxon Blur. The 1nF cap C 2 shunts high freqs to ground and out to mellow the signal.
This set up results in the rat pedal sounding its best. I scored a 90s Flat Box Rat last week at a screamin' deal from an unnamed big box music store new hires are surely a gift from god. I didn't know him, but I'm told Woodcutter was definitely the man, and did his job very well and very quickly, but he didn't wire them out of spec, in any different way, or have that I know of any magic mojo in his fingers. Part of the Rat's tone remains on the choice of the chip as a function of the Slew Rate, the Gain-Bandwidth Product, and the Compensation Capacitor: The Slew Rate. History In the 70s Scott Burnham and Steve Kiraly repaired and modded distortion pedals in a basement in downtown Kalamazoo, Michigan. With the following instructions you can date any pot and therefore date most of your vintage gear e. In all the vintage rat clones I've built its never one part that changes the texture and response.
If you do hobby building you should for sure get an affordable rat clone or original and pull some parts, put sockets in and start experimenting around to find what works for you. I have a few demos of the pedal comparing it to other pedals There is a big difference in a pedal with one good chip from a pedal built well with all good stufz inside. Each pedal was built in a standard project box, hand painted, and hand drilled. The top surface is too thin, it can be bent by stomping enthusiastically. Chiampi for helping us with the article. The Nocturne Brain is an American company that makes a great boutique version of a rat box. Along with possibly other component variations.
If John Scofield and Bill Frisell can use a Rat for just a touch of heat to give that slightly breaking up amp sound, it might just make it worthy of being considered king of the drive boxes. It has a ton of power for such a tiny pedal. I'd always considered the Rat to be 'high gain' only. The only thing I really read about the difference between those 2 chips in terms of sound result was that dialing in sounds with the distortion knob is more 'consistent. I did a demo video. But the lower gain settings sound great.
Got to be careful on heat with those and then you'll have to replace some of the resistors with low tolerance metal film to bring down the noise. I can get everything from a low gain to Ozzy Randy Rhoads sounds. If you go into it think it was just made for extreme distortion and set that control either high or to max, you will probably end up passing on a Rat every time and favoring other pedals. There are a lot of things folks love that I don't. The distortion stage is followed by a tone filter and an output buffer stage that ends up with a tone control.
Especially when the builder really cares about his products. Maybe I just haven't found the right Rat. The gain will be limited by op-amp characteristics and also by the clipping diodes action, as it will be studied in the Diode Clipping Section. Technical notes: The circuit in the two pedals is identical. Here are the pics: Click to expand. Artificially band-limiting a distorted signal, using both high and low-pass filters, can help it sit more comfortably in a mix, by preventing its spectrum from spreading over too wide an area. The voltages on the batteries read identical.