SHORT ANSWER:
After their guitar, most people like to run the following order:
Wah > Compressor > Pitch Shifter/Octaver > Envelope Follower/Auto Wah > Overdrive >
Distortion > Phaser/Flanger > Equalization > Chorus > Delay & Echo > Reverb > Looper
So, I'd have to say for your specific pedals:
Wah > Whammy > DOD FX25 > Zakk Wylde OD > MXR phase 90 > Boss CE-3
DETAILED ANSWER:
This is a perennial question on all guitar oriented forums - what order do I put my effects in? While there are some simple guidelines, there is no "right" way to do it. It's all a matter of taste & your personal tone. Let your ears be the final arbiter. The order of effects that produce the sounds most people have become accustomed to hearing is this:
Amplitude-altering effects
Pre-distortion EQ
Distortion
Post-distortion EQ
Small time delays & Phasers
Longer time delays - Chorus, Reverb, & echo
There is a rationale for the placement of each effect in this order; it goes something like this:
AMPLITUDE-ALTERING EFFECTS
As simple as your guitar's volume knob, or as complicated as fancy compressors, attack-delay or other note-shaping device. The idea here is that the basic "shape" of the note that will interact with the later distortion devices gets set for the best tone at that level. Because distortions are level sensitive, the higher the level that comes out of an amplitude device, the more it will be distorted in any following distortion devices, & vice versa. A distortion following a level changing device converts the level-altering device into a distortion-intensity modulator - & that reverts to level changes if you switch the distortion out.
PRE-DISTORTION EQ
Once again, as simple as your guitar's tone control (which is really a simple treble-cut filter) or as complicated as a parametric EQ; pre-distortion EQ sets up which frequencies are loudest - & the louder the frequency, the more that a following distortion will affect it. As I mentioned before, distortions are level sensitive devices - anything under the level at which distortion starts will be largely unaffected. Anything over the threshold will be distorted. So by boosting things we want distorted & NOT boosting things we don't want distorted, we can select the things that get distorted & have a much more animated sounding distortion. One of the most recognizable uses of this was Jimi Hendrix' use of a wah pedal (which is really a sweepable resonant filter - see the Technology of the Wah Pedal at GEO) before a Fuzz Face. A wah boosts one band of frequencies a lot, & if the levels are set right, the frequencies in the boosted range will be distorted most.
DISTORTION
The Ronco Veg-a-Matic of the sound world, distortions take whatever signal is coming in & slice it into analog coleslaw. In doing this, they add harmonics & intermodulation products that were not present in the original signal. This usually results in a hotter high end, as it adds more signal bits at higher frequencies that were originally present.
POST-DISTORTION EQ & TONE CONTROLS
Once the distortion has had its way with the signal & inserted a hash of harmonics into it, post distortion EQ can step in & select which bits out of this sonic stew get heard. As in many things musical, this started out unnoticed, just the nature of the beast. A 10" or 12" speaker in a cabinet has a frequency rolloff that starts between 4kHz & 6kHz, & is quite steep. This puts a serious cut on any real high frequency content from guitar. In fact, any "speaker simulators" are just multi-pole lowpass filters with turnover frequencies in the 4K to 6K range, & do a creditable job. Having noticed the post-distortion tone effect, we can mess with it deliberately, of course. Distortion devices make for lots of high frequency harmonics. We can cut, boost, trim, notch, & otherwise shape what the distortion device turns out. Notice that Pre-Distortion EQ changes what gets distorted in the first place. Post distortion EQ can only cut & trim on what has already been created in the distortion device. You should try it both ways - or both ways at once!. Notice that Post distortion wah sounds very different from pre-distortion wah. Try it! Anything else that does frequency shaping goes in here as well - remember the interaction of level boost-cuts with distortion.
SMALL TIME DELAYS & PHASERS
These add a spacious sound by causing multiple notches in the signal at specific frequencies. The ear is fooled into thinking it's in an acoustic space that has odd cancellations & echoes.
LONGER TIME DELAYS - CHORUS, REVERB, & ECHO.
SOME COMBINATIONS & THE RATIONALES BEHIND THEM:
COMPRESSOR BEFORE DISTORTION
Gives a "smoother" distortion sound because the signal level the distortion gets has less variation - the compressor wipes off more of the signal changes, so the distortion works mostly at one level, & the tone quality of the distortion changes less as the note decays. The disadvantage is that the hiss of the compressor is further amplified by the distortion, so this setup is noisier than either by itself.
DISTORTION BEFORE COMPRESSOR
The compressor adds little but hiss, because the distortion already sets up a fairly fixed output level. The tone quality changes as the distortion would without the compressor.
DISTORTION BEFORE TIME DELAY
The subtleties of the time delay, chorus, flange, etc. are generated after the distortion's harmonic hash, so the nuances of the delay can be heard.
TIME DELAY BEFORE DISTORTION
The distortion's harmonic generation tends to fill in the response notches the time delay created, usually less acceptable.
I hope this helps mate. In the end, only your ears can determine what your sound needs to be. Don't be afraid to experiment as the above information is only some general guidelines which are meant only from which to start! Remember, some people have an ear for Phaser before their distortion or even placing EQ up front instead of the end of the chain. Find "your" sound. In the end, the only right way is your way.
Finally, go check out my post over at Bossarea regarding Tone Loss. It covers things like breaking up a long chain of pedals to preserve your precious tone. http://www.bossarea.com/forum/topic.asp?TOPIC_ID=3892
