truth about Fullltone distortion pro....

[dubs]

A friend recently reversed engineered the distortion pro and worked out it is basically a heavily modded rat circuit.
Interesting...

[RedHouse]

Ask your friend to post his specific findings

[dubs]

Thanks to my friend for his hard work!!
As I quote from him:
"The IC was an LM308
R6 and R9 are internal trimmer pots. Their values were 10k and 5k respectively. Here are the other pot values:



Gain (R12) = 100kB

Saturation (R14) = 1kB

Voicing (I called it ‘mids’, but it’s not really) (R15) = 25kB

High (R18) = 25kB

Resonance (I called it ‘low’) = 25kB

Volume (R25) = 100kB


It’s interesting to note that this pedal is really just a modified rat at the end of the day,… he’s added the first transistor stage out the front (which doesn’t do much,… just amplifies the signal by a factor of 2 to 4). This has a trimmer he calls the ‘gain trimmer’ (R6). He’s simplified the opamp negative terminal network to ground by getting rid of the 560 ohm resistor with the 4.7uF cap, and just added a variable resistor there (very bad design!) which he’s called the ‘midrange trimmer’ (R9). He’s kept the original tone control from the rat, which he’s renamed ‘voicing’, but changed some values slightly. He’s then added a simplified tone stack for the low and high controls,… and that’s about it. Oh yeah, the ‘saturation’ control effectively mixes in some of the opamp output with the diode clipped signal."

[cd]

Use imageshack.us when you post.

[dubs]

done see above

[cd]

I don't see anything, did you use inline image tags or just a posted link?

[toneman]

what link?

[Lonestarjohnny]

I'll Be RAT FINKED !
Johnny

[jimbob]

Great investigating and work! Also thank your friend! Ill probably not build it since i have a milion all ready but i was curious about that one as well as many others..I hope there's not a long thread about ethics on this one..I am just limited on ethics right  now--and saving it for something more important ..

[dubs]

decided not to host schem anymore, because of ethics and will get me in hot water.  :oops:
I was only posting because it's supposedly  a variation of an existing circuit,  and not an unique, original  design like zvex etc stuff.
It's always interesting to see how people put their own flavour to things and this is not meant to be some ethics debate.

[bobbletrox]

Not to bring up the "let's knock Fulltone" theme, but I just happened to be reading a HC review of the Fulldrive before seeing this thread.  Even though this reviewer still game a positive review for the pedal, he/she says that they sent the pedal back to Fulltone because it didn't seem to be sounding so hot, and the reply from Fulltone was: "Pedal checks out ok.  Check EARS".  The reviewer continues saying that when they contacted Fulltone to get an explaination, Mike Fuller replied that his Tech had to stop work on a Tube Tape Echo to tend to the reviewer's pedal, causing them to lose money.

They still gave it a positive review though!  (1st review at the top)
http://www.harmony-central.com/Effects/Data/Fulltone/Full_Drive_2-01.html

Man, I was pretty surprised about that.

[Johan]

go to AMZ and look for overdrive-pro...
..just after the distortion pro came out there was a discussion on this forum on what was inside that little box and what it sounded like. with a little help from other forumites, Jack managed to design a box that sounded and behaved the same ( if I remember correctly)
I dont know how close this ciruit is to the Distortion-pro but there is  deffenetly is a RAT type circuit hiden inside..
..but then again, so is the Ibaneze Sonic distortion and many other boxes..perfection is in the details..

Johan

[black mariah]

Why would anyone be surprised to find that one pedal manufacturer has used anothers basic design? Didn't we get over this about THIRTY YEARS AGO when everyone and his younger brother made Fuzz Faces? Or TWENTY YEARS AGO when everyone's son decided to stat building Tube Screamers? Or TEN YEARS AGO when everyone's son's little cousin started building Digitech Whammy pedals.... ummm... waitaminute... :lol:

[mcrusk]

In the case of Fulltone, Is there anything he builds that is even partially an original design?  If there is, i would be suprised.  People seem to like his stuff so who am I to judge it.  Having said that, I wouldn't pay a quarter of what he charges for his pedals.  IMO, they are ho-hum and I have my own designs that I like better.  

Gary

[Satch12879]

Why would anyone be surprised to find that one pedal manufacturer has used anothers basic design? Didn't we get over this about THIRTY YEARS AGO when everyone and his younger brother made Fuzz Faces? Or TWENTY YEARS AGO when everyone's son decided to stat building Tube Screamers? Or TEN YEARS AGO when everyone's son's little cousin started building Digitech Whammy pedals.... ummm... waitaminute... :lol:

+1

And on that note, I'd probably shell out for a PC box before one of Douch-tone's

[WGTP]

Coming up with something original at this point in the distortion box life cycle is getting pretty tuff.  Has it been 50 years yet?  That's a while for a "tool" to be around in the modern world, althought the knife has been with us for millinia.  Notice how it continues to be tweeked with old and new technology.  Not too many new knife designs these days.  Bow and Arrow are other good examples, along with the wheel and cloths.  I guess cars are the same basic design, but we keep tweeking (I'd like to tweek myself into a new Mustang).  

I think a Fuzz Face with FETS is conceptually interesting. :shock:

Humans must be genetically engineered to tweek.  

Just changing 1 cap on a device can make a world of difference.   :roll:

[RedHouse]

I'm sooooooooooo tired of these post-n-bow-out "because of ethics" threads.

[AL]

Dubs, what schematic are you using? You mention numbers (R6 etc) and give values. Are these #'s printed on the Rat circuit board, on a particular Rat schematic, or are they Fulltone #'s? Thanks

AL

[Lonestarjohnny]

Shuck's, I'll be Double Rat Finked,  :lol:
Johnny

[Ed G.]

I wouldn't worry too much about what is in it. By all accounts that I've read on harmony-central (for which most people post glowing reviews of their gear) the reviews have been mediocre at best. A lot of people saying it's not the "300-pound violin" tone they were expecting.