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This page focuses on core tone, particularly distortion tone. Effects placement and impact are discussed individually on their own page, for each kind of effect. While effects are referenced below, they are only considered for how they affect core tone when they are set to be as transparent as possible.
The complete signal chain for a typical rig is
== Hands ==
== Pickups ==
Pickups are often an instrumental part of the tone, so be sure to [[Choosing Pickups|choose good ones]] for your guitar. There's no universal answer for what to get - the ideal choice depends on your guitar's tone (generally indicated from the mass and type of wood its made from), your desired tone, your amp or other distortion stages, and your playing style. Guitar manufacturers often outfit low to midrange guitars with crummy, in-house pickups. But even a somewhat high-end guitar might have poor stock pickups. Aside from being deficient in certain frequencies, poor pickups generally have a very poor signal-to-noise ratio. Its It's usually the first thing I look to replace in a guitar, as it has a very large impact on tone.
Some things to consider :
* High output has become an arms race for pickup manufacturers, but modern high-gain amps don't need high output to be driven to saturated distortion. Gain levels can also be augmented by a boost pedal, so high output is often completely unnecessary. And in the case of many digital devices, high output will pickups can cause input clipping. For some amps, you will get distortion even on the clean channel with minimum gain. I do use high output passive humbuckers, but they don't reach the extreme degrees that many actives and some super-hot passives deliver. I've used such actives and found the output to be a severe negative rather than a positive.
* Magnet types can give you a good indication about the response of a pickup, but design still matters.
* Pay attention to the relative frequency response metrics given by a manufacturer. This will have a big impact on distorted tone. See [[#Boosts and Frequency Response|below]].
Be very careful when switching from active to passive pickups or vice versa. Actives usually have much different ideal values for pot resistance and capacitor values. Trying to swap just the pickups but keeping the electronics is a recipe for disaster. If you plan to reuse anything, be sure to read its values carefully. Don't confuse a 25K pot for a 250K pot. Don't confuse a .22mf cap for a .022μf cap. The results can cause very odd things to happen. When changing pickups, it's often a good idea to first wire them up connecting one at a time directly to the output jack to get a good idea of what they should sound like.
See [[Choosing a Guitar#Electronics]].
== Stomps ==
=== True vs. Buffered Bypass ===
There's a lot of debate as to which is better - true or buffered bypass. ''True bypass'' means the signal coming from the guitar is passed directly into the output of the stomp device when the device is set to bypass mode (essentially means it is off). ''Buffered bypass'' means the signal is received by the device and run through a transformer or low -power amplifier in the device, even when it is in bypass mode. True bypass should basically be invisible, as though it was physically removed from the signal chain, while buffered bypass will have some impact on the signal.
Now, which is better? Well, that depends. Passive pickups output a high impedance signal, at least on peaks. Trying to send that load through a lengthy instrument cable will lead to attenuation of high frequency components. In other words, it will dull the tone of your guitar signal compared to a shorter cable. This can be avoided by using a most buffered bypass pedals, which will output a low impedance signal which will retain its frequency response through a longer stretch of cable.
But before moving on, depending on the length and type of cable you use between pedal and amp, you may find you get a better SNR by using max output on your boost. Try it both ways - make sure when you compare that you are getting the same distortion saturation so you don't have a false comparison. In general, the output knob of a boost pedal should be a simple transparent amplifier, having no bearing on the tone of that device.
You may have other reasons to turn up the volume/output on a boost pedal - where you are using the unboosted amp tone as one tone and the boosted tone as another, switching between them the same way as switching channels on an amp. In that case, you should use that as you please rather than working inside of a meaningless set of rules.
=== Boosts and Frequency Response ===
I always like to start with using an EQ alone as a boost - it is more transparent and offers more control than most boost pedals. Then you can find where the sweet spots are for your guitar and amp. If you also like the tone of some boost that isn't strictly related to frequency response, try to use it with as neutral settings as possible and use EQ to refine the resulting distortion. Then try it with neutral EQ and use the boost's tone to find the sweet spot. The best settings are probably somewhere in the middle of these two, using both the boost's tone and some EQ refinements.
See [[Dialing in Distortion Tone]] for more on boosting and using pre-EQ to shape your distortion tone.
=== Dirt, Distortion, and Fuzz Pedals ===
* [[EQ|External EQ]]
* [[Modulation Effects]]
* [[Pitch ShiftersShifting]]* Wah [[Wah Pedals ]] (if you want the '''''Rage Against the Machine ''''' - ''Bulls on Parade'' tone)
* Volume Pedals
* Unique Processors
== Power Amp ==
=== Guitar Power Amps vs. Pure Power Amps ===
When it comes to power amps, there are two kinds. '''Guitar power amps''' are the ones built into complete guitar amps but can also exist as discrete units. In the context of a guitar amp, it may be referred to as ''the power section''. They are designed to have some impact on tone, although not as much as a [[#Pre-Amp|preamp]]. They often use tubes, and may even be designed to be pushed into overdrive, or may at least offer differing tone at different volume levels. '''Pure power amps'' ' or '''FRFR amps''' (full range, flat response) on the other hand, are designed to be as transparent as possible, ''only amplifying '' the input signal with minimal impact otherwise.
In earlier years, these different types of amps rarely crossed paths. Guitar power amps were for guitarsusually built into guitar amps (or those manufacturers would make clearly-designated guitar-centered power amps), and pure power amps were for PA systems. With the introduction of modelers, which that simulate guitar power amps, cabs/speakers, and microphones, pure power amps began to be used by the guitar community for amplification purposes, the same way a mic'ed guitar cab would be amplified through a PA system. Rather And rather than running them into guitar cabs, they'd run into full-range, full-response (FRFR) monitors. Some brands market power amps that bridge the gap, claiming they work for both purposes.
=== Headroom ===
=== Speaker Wattage ===
Speakers are typically rated in wattage, beyond which they will start to exhibit distortion. Some may find it appealing, but I find it difficult to control and too rough sounding. That said, it's rather difficult to achieve. A 4x12 cabinet with 30 watt speakers will require 120 watts of power to distort, while most amp heads provide only 100 watts. Furthermore, even if an amp is run full open, it is [[Choosing_an_Amp#Watts_vs._Volume|not necessarily outputting a full 100 watts]].
=== Cabinet Back ===
Another huge impact on tone is the construction of the back of the cabinet. The back of the cabinet is important because as the front of the speaker pushes air outward, the back of it the speaker is pulling air in the opposite direction. Sound travels in all directions, and without a cabinet at all, a speaker will absorb most of the sound pushed from the front by pulling from it from the back. Directionality is frequency dependent (sort of - dependent on the size of the speaker), with low frequencies spreading more than highs. Thus, speakers will sound bright and thin without a cabinet.
Typically, there's either open back, half-back, 3/4 back, or closed back. Any kind of opening in the back will cancel out some lows, with the smaller the opening, the less lows canceled out. Furthermore, a fully closed design will have a stronger impact on resonance, covered below. On the other hand, a fully closed back requires compressing the air inside the cabinet, which means more of the speakers' energy is spent on compressing air vs. outputting sound. So open back designs are louder than closed back.
Some modelers allow you to tweak the resonance of emulated cabs virtually, effectively allowing you to tweak the cab's construction in real-time. This is great for dialing in your dream tone, although they tend to sound weird when fake when you deviate too far from center.
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== Gain Staging ==
'''Gain staging''' refers to setting the levels of each device in your signal chain to achieve the highest signal-to-noise ratio (SNR) while avoiding unwanted clipping (distortion).
Analog devices (and digital devices that emulate them properly) have a '''noise floor''' - a small amount of noise that is inherent by nature and cannot be reduced. Running your devices to output at maximum strength means that The further the signal is much higher than this attenuated, the louder the noise floorwill be relative to the signal, maximizing decreasing the SNR. Amplifiers cannot differentiate between signal-to-and noise; they just amplify everything they receive as input. (Devices have other forms If any part of inherent noise that will increase with certain settings and output levels, but we are only concerned with the signal level vs. noise floor here.) Depending on chain lowers the settings of the deviceSNR, maximum output may be too strong for its internal amplifier and clip there is no way to improve it. Then output should be reduced to avoid clippinglater in the chain.
Running your devices to output at maximum strength means that the signal is much higher than this noise floor, maximizing signal-to-noise. (Devices have other forms of inherent noise that will increase with certain settings and output levels, but we are only concerned with the signal level vs. noise floor here.) Depending on the settings of the device, maximum output may be too strong for its internal amplifier and clip it. Then output should be reduced to avoid clipping. Usually devices are designed with enough headroom so that their internal amplifiers don't clip, even at extreme settings and max output. However, when creating a whole signal chain, several devices that can boost the signal connected together are very likely to clip when they are all set to maximum output. Proper gain staging dictates that each device should have the maximum output to not only avoid clipping its own amplifier, but also the input buffer or other uncontrollable aspects of the next device in the chain. This ensures that every spot in the chain has the best SNR possible without unwanted distortion.
The way you have to test this all out is by using a completely clean tone. If there's any distortion, you have to turn down one device at a time to locate the source of the clipping. Many times you want a distorted tone, which can mask unwanted clipping and make it difficult to tell where it is in the signal chain. You have to listen with a very careful ear, or substitute distortion for a clean tone of approximately the same volume level.
Let's look at an example signal chain:
We start with the pre-amp and power amp - those are the only parts of the chain that ''have'' to be on. Everything else is set to bypass or removed from the signal chain for now. We set the pre-amp to a clean channel, minimum drive (if available), and a conservative channel volume. We set the master volume of the amp somewhat low - loud enough to hear but the tone should still be clean, definitely far below the amp's clean headroom. This is our baseline to set up at least the stomp effects (before the amp).
=== Room Placement and Conditioning ===
One thing that cannot be understated for a mic'ed tone is the room where the cab is mic'ed. Preventing all reflections from a room is virtually impossible and also undesirable. A mild reverb makes for a natural sound. Try listening to synthesized sounds with no reverb through earphones, and you'll find that the sound is uncomfortable and quite artificial. Many studios treat their rooms not to eliminate all reflections but to minimize some of the nasty effects they can cause. In particular, they avoid parallel walls which produce ringing at certain resonant frequencies depending on the size of the room. If a room does have parallel walls (extremely common), placing dampeners on each wall so sound will not reflect back and forth directly between two opposite walls will be the most beneficial to prevent ringing. Also, normal dampeners will not affect low frequencies, requiring bass traps to do so.
Even with good treatment, there will still be some nodes and anti-nodes throughout the room for certain frequencies. This is where cabinet and mic placement becomes important. Even with the most expensive gear in the world, if your mic is in a dead spot, your frequency spectrum might have a critical null that is like putting a blanket over the tone. If you find you just can't get a good sound, even after messing with mic placement for a long time, try moving the cab around the room and re-mic'ing - you might be hitting a node. Unfortunately, it's pretty difficult to determine where in advance a node will be - it depends not only on the size and shape of the room, but the placement of the cabinet and the frequencies being produced. It's best to avoid corners, which tend to be bass nodes. Otherwise, a bit of experimentation is in order. === Near Close vs. Far Mic'ing ===Close mic'ing (anywhere from inside the speaker cone to several inches away from it) tends to capture the direct sound of the speaker and cab, minimizing the effect of the room, other than direct reflections from the ground or very nearby walls. Far mic'ing captures more of the room's sound with its reverb. Guitar tones are typically close-mic'ed, with reverb being added either post recording or by an effects processor in the guitar signal chain, transmitting through the speakers. That said, if you have a good room, far mic'ing can get you a sweet natural reverb. Or you can mix the two together to get an optimal relative balance - just be sure to adjust for latency in the far mic to prevent comb filtering.
=== Mic Pre-amps ===
Some mics require phantom (or actual) power to operate correctly. Some people believe mics need to be run through a pre-amp to sweeten up their tone. Pre-amps can also provide common effects like compression, EQ/filtering, or mild distortion. I don't know much about mic pre-amps, but most professional studios do tend to use them, often being incorporated into the mixing board, before converting the analog signal to digital for recording and post-processing. As such, they can be an important part of the signal chain, having either a subtle or profound effect on tone.
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[[Category: Guitar]]
[[Category: Gear]]
[[Category: Tone]]
[[Category: Setup]]
[[Category: Amps]]
[[Category: Cabinets]]
[[Category: Mic'ing]]