The number ONE rule for building a good pedal chain is that there are no universal rules. Crafting a sound is a complicated process that requires various experiments and yields different results depending on the setup.
PEDAL CATEGORIES
In my experience, a typical chain should be assembled in this order:
- Tuner
- Wah-Wah
- WHAMMY
- Compression
- Overdrive / Booster
- Distortion / Booster
- EQ
- MOD (Chorus/Flanger/Phaser/VIBE)
- Delay
- Reverb
- Volume
Here’s a brief description of the categories:
Wah
The pedal controls a potentiometer that adjusts the EQ: lowering and raising the pedal generates the effect represented by the onomatopoeia Wah-Wah.
Compressor / Limiter
The compressor is a somewhat overlooked pedal because it can tend to make the sound lose transparency and can heavily impact the dynamics.
This pedal acts on the sound by leveling the output, reducing volume fluctuations.
One effect of this pedal is the increase in sustain.
When it comes to David Gilmour there are 3 main uses of the compressor: enhancing the attack, get more sustain, give the guitar a slight boost.
There are situations where David Gilmour stacks 2 compressors: the goal is getting more compression and attack.
Boost / Overdrive / Distortion
The booster typically serves the purpose of raising the signal level, or the output volume, without significantly impacting (there are very clean ones) the quality of the initial signal.
Overdrive and distortion, on the other hand, work differently by saturating the sound. Overdrive is usually used to make the sound grittier, dirtying it in a more or less aggressive way.
Distortion, instead, serves to create a full, powerful, and warm sound.
For this category as well, the effect involves an increase in sustain.
It is possible to chain (stack) overdrive and distortion pedals, giving the overdrive the function of a booster.
The order depends very often by personal taste, although there are pedals which IMHO aren’t really suitable to be placed as boost after distortion. One example is the TS9 (I personally tried the TS808, more or less same pedals): while it’s ok to have it before a big muff, where it will boost the mids and the gain, if you place it after a big muff it will flop your big muff.
“Boosting” the Big Muff with the Tube Driver
Regarding this particular habit of David Gilmour, after some tests, I initially found it more effective to use the Tube Driver before the Muff, mainly because I was setting the TD incorrectly.
In reality, I discovered that for this function, the drive must be kept at a minimum: the settings are as follows.
DRIVE
4-5 notches (not the ones drawn around the knob, but the ones you feel click when you rotate the potentiometer)
VOLUME
2 o’clock.
In my TD, I replaced the stock tube (12AX7) with a 12AU7/ecc82 for some time before going back to the original.
So be careful!! Don’t take anything for granted! Everything needs to be tested with your own setup!
Equalizer
Although often each pedal has a tone control that can adjust highs and lows, it’s a good idea to use an equalizer for greater control over certain frequencies.
In fact, it can significantly enrich the sound quality by using it as a mid-boost (that is, to enhance the mid frequencies), since it is placed after the gain pedals.
It is also possible to use it as a post-gain booster by using the volume control.
Chorus/Flanger/Phaser/VIBE
All these pedals belong to the MODULATION group. These effects all work similarly, creating a copy of the sound, applying a phase shift, and outputting the mix with the original sound.
Delay/Reverb
Delay is a signal repeater that can be analog or digital. With set values for time, feedback (repetitions), and mix (level between clean and affected signal), it repeats the signal over time.
Reverb reproduces the effect of a sound moving through space, lending more realism.
See also this video about ambient in Gilmour sound.