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19 October 2012

The Cost of the Cup of Tone

Introduction


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From some time, I am thinking about tone and wondering what's really true and what is just snake oil.
I made lots of statements to myself, trying to run away from GAS, trends or sexy looking gear.
Thoughts as: "guitar's wood cannot have a big impact on tone, pickups are generating the tone, you change the pickup, you change your tone" or "any guitar cable should work, it's just transmiting the signal" or... you get the picture!.

Experience always confirms or rejects what the satisfied mind said and, OMG, I was often wrong, trying to avoid any single change to my gear that supposed an additional cost!.
We always tend to think that in our axe is where the tone is and, that the rest of the chain is just adding some little bricks to our well based building.

You will see discussions about if guitar tone's caps sound different or not. There is nothing in electronics theory that can support this but, the truth (for a group of guitarists, including myself) is that different caps sound different (another discussion is how much this affects to the overall sound and, if it worths the money go for that cap or the other).

You use same pickup in two different axes with same construction, let say LP-like but of different qualities, let say a Gibson and a cheap Chinesse one and, they don't sound the same. Isn't the pickup the device that generates the signal?. So... what's the buzz there?.
You even get two axes of the same maker / model / price and they can show differences that make you to choose just one of both and, I am not talking about the look but, how you perform on each axe and how it sounds to you.

I bought 6 different cables, from cheap to high end to demonstrate to myself that cables will sound the same, using same axe, same amp, same overall setup and... I failed!, I had to recognize that cables sound and feel different!.

What about solid state or tubes?. They are just amps, they should just amplify what is being generated in my guitar, just making it louder... why people loves tube amps, that are a mess from the maintenance point of view?.
What about tubes themselves?. NOS?. If an slot is prepared for 12AX7, everything should sound the same just throwing there any 12AX7 tube of any maker any brand right?. Damn wrong!.
And if the tube is the holy grail in amp A, it should be the holy grail on the rest of my amps, right?. Damn wrong!.

And about speakers? shouldn't they just transparently convert to sound what the amp amplified?.
Why some people wants pre-amp X and mic Y to record their takes in studio?.
And, why in the hell audio or musical stuff is so damn expensive?. Aren't electronics components easy to source and cheap enough?.

Well, you get the kind of questions that were rolling on my head for several years and, after my own experiments, readings and observation, I think I can start to understand what's happening here.
Interested? Let go...


Chain Reaction

What's our first tone generator?. The pickup, for sure but, the pickup itself isn't the whole equation. Firstly, the pickup generates its signal depending on the electricity that it's being induced by the changes in its electromagnetic field, mainly altered by the movement of ferromagnetic strings.
So, type of strings, gauge, entorchment, core desgin (circular, hexagonal, ...) and materials make a difference.

But also, the rest of parts that conform that system called guitar have something to say in the way as those pickups translate the strings' movement into electrical signals. Materials used for body, neck, fingerboard, frets, nut, bridges, stoptails, tuning keys, etc, as well as their dimensions, weight.
Wood grain and pattern, how was the cut, humidity level, among other variables, all these sums up to get a different "starting tone" or, at least, some different nuances of the same foundational tone.

But, the resulting sound, isn't just depending on how the guitar's caracteristics affect the pickup's magnetic field, the rest of electronics components after the pickup affect pickup' sound, as well.
Which potentiometers are after the pickup, which capacitors, which resistors, which cable and how it's the input in our amp affects the way the pickup works.

A pickup is itself a complex combination of an Inductor, a Resistor and a Capacitator but, straight electrical variables doesn't gives you everything about how they sound and, they can sound better or not, depending the rest of your rig.
Seeing a pickup in a very monodimensional way, its caracter is mainly influenced by its resonant frequency and its resonant peak. This gives to the pickup its natural place in a frequential chart.
When you are mixing, you need to bump some frequencies and dime others for a certain instrument to make it "to cut the mix". That resonant fequency and peak are doing just that, to make your guitar more present in a certain range of frequencies. If that range suits the natural guitar presence range, your guitar will be clearly audible in the mix, without big help. If that range suits the natural space of other instruments, an very specially the voice, your guitar (and the other instrument in conflict) will be lost in the mix.
Most of us, tend to increase the volume, instead of changing the amp's EQ or, to use some EQ pedal to better suit the rest of the band.

As said, the pickup is complex enough by itself but, things going even worst when we consider the rest of guitar electronics that (among other effects) can change that resonant frequency, that resonant peak or even the way the pickup is rolling off trebles after the resonant notch.
A higher resistance value for a pot, will increase the resonant frequency, making the pickup to sound brighter (or even harsh or honky). A lower resistance pot value will lower the resonant frequency, making the pickup to sound duller or warmer (or even muddy and dark). When you stack more than one pot, you are adding resistance increassing the resonant frequency, and so on.

Guitar cable has also some resistance and capacitance values and changes the high frequencies that are being rolled off and even the resonant stuff.
Also, the input of your amp has a resistor suited for a certain impedance level (usually of about 1 MOhm) and this also affects the resonant stuff.

But, dude, we also love pedals because they can add some other nuances that we love for certain things and, pedals are full of resistors, transistors, capacitors, potentiomenters, all them affecting the overall system.

Then we have that amp, full of tubes or transistors, diodes, resistors, capacitors, transformers, rectifiers, etc., where the signal is being "just amplified". The amp delivers its results to the speaker or cabinet and the speaker translates the electrical signal into that sound preasure waves that we call sound.

But, wait, if it must go thru a PA system or mixing desk, you will use a mic or more, and one or more preamps and then, the resulting mix will go thru some other speakers systems, ...

Yup!. Long run, from where the original tone was generated to where the resulting tone is being delivered. And, the worst of all, your original tone deads just in the first device it inputs!!!.


Preserve my tone

Aha!. That's our main objective to preserve "our tone". But, we don't often realize is that this tone is the result of the whole chain and not just of a subset of gear that we use.
Use a different pick (or plectro), of different shape, stiffness, material and grip and be surprised yourself about how much your performance changes.
Use a different brand of strings or, just a different model (pure nickel, steel, brass-nickel, different core shape, different entorchment...) and see how your "tone" changes.
Use a different cable, from guitar to pedal board, within the pedal board or from pedal board to amp and see how your "tone" changes.
Re-arrange your pedal board in a different order and see how your "tone" changes.
Plug all this in other amp and see how your "tone" changes.
Swap your amp's speaker and see how your "tone" changes.
Use another mic, or change the distance, height and direction were it's being placed and see how your "tone" changes.
Use a different preamp with the same mic and see how your "tone" changes.

Every little change in our system can affect in a a very subtile or dramatic way to our tone.
But, why are we choosing a certain tube, a certain amp, a certain speaker, a certain mic, a certain pre-amp if our tone is being generated in our axe and, the rest of chain should just amplify it to make it louder?.


Tone has dead, long life to Tone

Resistors, capacitors, potentiometers (variable resistors, at the end), are just tone filters. They help to modify the frequential content of our signal. For sure, their work can be so noticiable to ruin or enhance our tone but, they are in some way, passive components that work over the signal that is crossing them, they don't generate signal themselves.
Once we reach an amplification component, our original tone deads and a new tone births.

Imagine that you go to one of those key-copying machines to make a copy of your home's key. We use our original key as the model and, the machine works in a virgin key to sculpt its teeth and slots. But, the key will still work if we changed the shape of the key's head (from circular to squared or hexagonal...). We can now use that new copy as a model for a new key and the new one for one more, etc.. But you know that, from time to time, copies doesn't work fine and you have to come back to the copying machine for some modifications.

Ok. Something like this occurs when we are reaching some amplification component or any transductor (that changes a type of energy in other type, as electric signal to sound presure, by example). The original signal is our original home's key that serves as model to sculpt the new signal but, at the end, we have a new signal (a copy key), not the original one.
Transistors and tube valves generate a flow of electrons from the emitter (or cathode) to the collector (or anode or plate), how much electrons are crossing both spots its being regulated by a third spot (the base or grill) and, it's just to that spot to were the "original" signal is being attached. So, the transistor or the tube generates the signal and, our original signal just regulates how it does it, serving as a model but, at the end, a new signal is being generated (a new key).
Usually a pre-amp tube has two amplification stages (two triodes) and, we can often see little amps with a pair of pre-amp tubes and a couple of power tubes, what means different "copying-machines" in series. After each triode, pentode or transistor, we have a new signal modulated by the previous one (original or copy).

Same happens with integrated circuits that cover amplifying tasks as op-amps, etc.

Pickups, microphones and speakers are transducers. They convert some kind of energy in a different type. Magnetic pickups convert the vibrational movement of strings into electrical signals. Piezo pickups sense the vibrations of the part where they are attached and transform such a vibrations into electrical signals. Microphones (traditionally) have an small diaphragm that moves with the sound preasure, moving a magnet over a coil what generates electrical signals. Speakers work in the oposite way than microphones, transforming that electrical signals into sound preasure.

If you are interested on all this, you should probably heard before that "simple designed" amps, with "short signal paths", have a best tone and, this makes full sense, if you think that we are reducing the number of "copying-machines" in series and, therefore, the number of copies of copies that we do of our original signal.


Amplification accuracy and Musicality

To make the best possible amplified copy of the input signal, all the electrical magnitudes should be multiplied by some factor but, they should preserve the proportion, just like if you wanted to zoom in a picture without pixelation. Anything that changes the proportionality in a single variable is known as Distortion. Using the example of a picture, when zooming it, distortion can be pixelation, defocused image, lost of colors, brightness, contrast, etc.

Every amplification component or transductor distorts the copy in one or more different ways.
Hi-fi devices are being designed to deliver an amplified image of the original signal with the less possible distortion levels (high fidelity). And, that's ok, because the source sound is already "cooked" (recorded, mixed and mastered). But, this is not the case of guitar stuff.

Did you hear your electric guitar unplugged?. Do you really like how strings sound?. Can you imagine that your gear is just giving you a loud exact version of that sound?.
So, some levels of distortion of some types are welcome in our guitar gear. Some distortion types sound more musical than others to our ears so, the kind of distortion that every "copying-machine" introduces in the signal has a lot to see with the final sound and how much we enjoy it.


Magical Parts?

In our guitar world and, extensively in the whole audio world, lots of gear are hyperhiphened. Is there anything real there?. Snake oil?.
Based on what we were discussing above, every amplificator or transductor will generate its copy with a certain degree of distortion (as even or odd harmonics, floor noise, etc) and, all them do it in different ways.

Ironically, transistors create amplified copies more accuratelly than tubes but, the kind of distortion that tubes introduce are felt as more musical, instead.
But, not all transistors work equally. Germanium tansistors are very raw and unstable, producing a sound that feels more musical than silicon ones but, that happens only when working fine. They are very sensible to temperature and other environmental changes and, they need often to be rebiased to get their best. But silicon transistors are more reliable and they always deliver same tone so, you have no surprises.
To fine tune a set of germanium transistors is certainly an art. A fuzz is one of the simplest pedal effects design but, even using the same transistors, some pedals seem to have more magic than others. Most of "self-made" pedals simply doesn't deliver that magic.

There are many kind of amplification components (JFET or MOSFET transistors, by example) and, some seem to work more musically than others, more close to how a tube valve works. What every maker chooses for each part of its circuit counts for the resulting tone.

There is a lot of noise around lots of components, depending on if we are talking about an amp, a pedal effect, a guitar or whatever other part of our gear.
By example, discussions about amp's resistors (carbon resistors give a warmer and raw sound but increase floor noise), coupling capacitors (some magic brand/models there), transformers and, even the material of the eyelet cards for wiring the components or the metal used for the frame.
Discussion about tubes goes so far as you want, not only talking about NOS (New Old Stock) tubes but, also discussing on how every internal component of the tube affects the tone.
Pickups are another good example, wire type and gauge, isolant type, magnet composition, shape and size, rods, screws, spacers, covers, etc. Everything sums up for the tone.

The magic attributed to certain NOS components (Tropical Fish or Buble Bee capacitators, Mullard Transistors or Tubes, etc.) has created a good ground for pedal or amp boutiquers, with more or less success but, always at high prices.
Similarly, we are seeing every day more cable boutiquers also, that aren't real cable manufacturers but which order special production runs to a cable maker under their own technical specifications (by example, Lava cable is made by Sommer Cable), in a similar way as the Tube Rebranders do (as TAD, Ruby Tubes, Groove Tubes or Harma), for just a few models of the tubes they sell.

Do two components of same electronic value, but different making, affect the resulting sound?.
Well, I cannot test everything but, all the experiments I did to convince me about the contrary went wrong and, at the end, I had to recognize that they affect, sometimes in a very subtile way, sometimes in a very clear way.
A resistor seems the most stupid, dummy and passive component that an electronic circuit can have. It just resists to the pass of current and disipates the "stolen" energy as heat. How in the hell can two different resistors with same resistive value give different nuances to the signal?.
I didn't experienced that personally so, I have not a formed or firm opinion. If I read amp boutiquers, they seem to agree that carbon resistors have some magic (probably because of their imperfections and rawness) but they are so noisy that they usually end mounting carbon-composite resistors instead, as a compromised solution between the "most musical but noisy" resistors and the "most accurated, quiet but sterile sounding" ones.

Strings make a difference, picks make a difference, pots make a difference, jacks make a difference, capacitors make a difference, wood makes a difference, nut's material makes a difference, wires inside make a difference, cables make a difference, tubes make a difference, ... I've experienced lots of things and, they certainly make some difference but, not all have the same "weight".


The Cup of Tone

Imagine your "tone" as a void cup. Each part of your gear is filling up the cup with some drops. Some parts fill up the cup more than others but, every drop contributes to fill up the cup.
To me, snake oil is anything that I try and for which I (personally) cannot distinguish any change in tone. This doesn't mean that no other people can hear something and be of their interest.

Then, there are those things that I really feel as affecting the tone in some way. If they affect the tone in a bad way, I am not interested on them anymore. If they affect the tone in a good way (always from my very personal perspective, that doesn't have to match yours!), my interest will depend on how much it helps to fill my cup of tone and, what economic effort it represents.
By example,its more important a different capacitor or a different pick?. Clearly, a pick (plectro) has more impact in my tone, since it seriously affects my performance (attack, speed, dynamics...) and, lately the resulting tone. A PIO (Paper In Oil) cap sounds to me warmer and smoother than an Sprage Orange Drop, even if it is theoretically removed (tone pot at 10) but, most of people doesn't seem to hear the excessive harsh frequencies of the Orange Drop. Even hearing that differences, the "weight" of that tone drop is so small that I have no way to justify to use an expensive NOS PIO cap. I can stand a reasonable priced modern PIO cap, as Sprage Vitamin Q or Mojotone Vitamin T or Q but, nothing else beyond that price.
Best practice is to focus first on the tone drops that fill more the cup of tone and then, go for the drops with less "weigth".

Guitar must be ergonomic and have a good resonant wood. To get guitar X because your hero has it, even if it is the guitar that worstly suits you its an error (that everybody, including me, does at some time). Maybe stock pickups aren't what you wanted but, if the guitar is good enough, you can only enhance it with changes, later, when possible.

The amp is even more important than the guitar. There is a rule that is plain true: use a bad guitar in an awesome amp and you will get a good sound, use an awesome guitar in a bad amp and you will get a bad sound, use an awesome guitar in an awesome amp and you will get an awesome sound.

The speaker or cab is so important as the amp is, because is the last "copying-machine" (if we are not using mics) in your chain. A change of speaker can produce a dramatic change in distortion grain and type, headroom, frequential representation and loudness, by example. Usually, amps makers are pairing their designs with certain models of speakers, as they designed the amp to sound and, usually there is no reason to swap the speaker but, if you want to experience it, try your amp's head with whatever speaker models that supports your amp's power and that matches the impedance levels of the amp (ask your friends to let you test your head with their cabs or speakers!) and, how knows it!, maybe you will find a speaker that helps you to fill half of your cup of tone.

Every pedal effect that you insert in your chain must help you to go where you want. If it compromises your tone,it doesn't matter how expensive it is, how recognized is by the dedicated press, your friends or forum mates. If it doesn't works for you, resell it and try another one. Sometimes, the pedal will work fine alone or in a different positon in your chain, try all that before rejecting it because, maybe you have to reject other pedal that compromises that good pedal, instead. Remember that every pedal is just one more (or a chain of) "copying machine" that generates a new signal.

To me, this vision of my gear as a chain of "copying machines" helps me to understand why some changes work better than others and, why I am feeling more comfortable with certain gear than other. It also helps me to understand the myths of studio gear. I can understand why a certain mic preamp will work better for your tone or why a certain processor (compressor, leveler, equalizer, mixing board, preamp, ...) will suit better your song.

Alright. All that basically summarizes my thoughts and experiences along several years. For sure, when I had no economics possibilities to buy even the cheapest of the pedals or to buy a complete set of strings (but just the 1st string to substitute the broken one), I had nothing to worry about. My tone was what the gear I had helped me to deliver, and that was all, but I recognize that I wasn't never satisfied with my tone. Nowadays, my cup seems more filled than void (contrarely to my pocket!) and, that makes me feel happier.

Unfortunatelly, gear that has real magic is very few and, since we live in an offer-demand market, the prices go so high that every drop of tone seems to be made of gold or platinum, instead of clear and fresh water.
I wish the good things were reasonablely cheap, for the love of music, instead of for the love of money!.

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1 comment:

  1. My brain hurts. Thanks for the giving us all something to think about...and something to be a little sad about.

    ReplyDelete

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