What about ADSR envelope of the tones transmitted by pickups?

[Kindly Killer]

I just had a thought about how different pickup construction yields different attack; and I know that some are more sustain-y than others. Is there a kind of consensus on which factors have effects on attack, decay, and sustain?

E.g. my experience is that MIM type strat pickups have a much mellower attack that is easier for me to play. Then if I switch to A3 rods in the same coils, the timbre is more beautiful but the attack is louder relative to the overall envelope, then A2 louder still, and with A5 more still. Degaussing seems to tame attack while it kills high frequencies. How are these related?

I've noticed that Alumitones/Transensors have longer sustain compared with similar shaped/sounding conventional pickups. Why is that?

After frequency response curve, this is the biggest factor in how a pickup sounds/feels to play, right? And some pickups are different, right? E.g. my totally unscientific, unfounded feeling about Trisonics is that they have a very nice, characteristic ADSR envelope that makes them very agreeable for me to play.

I did a search for "ADSR", then "attack" but there isn't much written here about it. And of course most of the books I have just list what models Gibson, Fender, et al made in the 1960's and list DCR.

Is there a body of knowledge about this stuff? If there isn't much interest, why? Is it because you're often still limited to the harsh attack and fast decay of swatting at the strings with a pick - or maybe because it can all be manipulated electronically, anyway (seen as the domain of electronic effects)? If there are threads on this I would love to have the links. Seems like there must be a conversation on this already but I can't find it.

[salvarsan]

I just had a thought about how different pickup construction yields different attack; and I know that some are more sustain-y than others. Is there a kind of consensus on which factors have effects on attack, decay, and sustain?

Guitar scale length and string tension have the greatest effect on the amplitude envelope.
If it didn't, the single coil middle pickups on the Alvin Lee ES-335 and the Stratocaster would sound a lot more alike.

[bbsailor]

I just had a thought about how different pickup construction yields different attack; and I know that some are more sustain-y than others. Is there a kind of consensus on which factors have effects on attack, decay, and sustain?

E.g. my experience is that MIM type strat pickups have a much mellower attack that is easier for me to play. Then if I switch to A3 rods in the same coils, the timbre is more beautiful but the attack is louder relative to the overall envelope, then A2 louder still, and with A5 more still. Degaussing seems to tame attack while it kills high frequencies. How are these related?

I've noticed that Alumitones/Transensors have longer sustain compared with similar shaped/sounding conventional pickups. Why is that?

After frequency response curve, this is the biggest factor in how a pickup sounds/feels to play, right? And some pickups are different, right? E.g. my totally unscientific, unfounded feeling about Trisonics is that they have a very nice, characteristic ADSR envelope that makes them very agreeable for me to play.

I did a search for "ADSR", then "attack" but there isn't much written here about it. And of course most of the books I have just list what models Gibson, Fender, et al made in the 1960's and list DCR.

Is there a body of knowledge about this stuff? If there isn't much interest, why? Is it because you're often still limited to the harsh attack and fast decay of swatting at the strings with a pick - or maybe because it can all be manipulated electronically, anyway (seen as the domain of electronic effects)? If there are threads on this I would love to have the links. Seems like there must be a conversation on this already but I can't find it.

I believe it has to do with pickup coil time constant (TC) that mainly controls the slope of the initial string attack. A typical strat-type pickup is about 2H and about 7K ohms. That strat-type pickup has a TC of .0002857 seconds (or 3.5Khz) based on the TC calculation of L divided by DCR. Take a current-based Alumitone type pickup with a low impedance string loop of 300 micro-ohms and a primary loop impedance of 5 micro-henries and you get a primary string loop TC of .016666 of 60Hz.

Based on my research on low impedance pickup design, I know that you can tune the tone of the current-based pickup by changing the resistance of the primary string loop. Also, the resistance of the primary string loop reflects its impedance into the secondary by the primary loop DCR multiplied by the square of the number of secondary turns. A 2000 turn SPCT 251 current transformer with a 300 micro-ohm primary loop produces an output of 4,000,000 X .0003 equals about 1200 ohms.

You can't measure these low resistances but you can select the metal you are looking at, the length and thickness on this link Resistivity Calc

I am sure that other technical members of this forum can add more details, verify or refute my observations.


Joseph Rogowski

[fieldwrangler]

I really feel that this is one of the main things I've been pursuing for the past several years; don't really know how to quantify or measure it but I do try to feel it.

Bob Palmieri

[David Schwab]

Guitar scale length and string tension have the greatest effect on the amplitude envelope.
If it didn't, the single coil middle pickups on the Alvin Lee ES-335 and the Stratocaster would sound a lot more alike.

Also if you stick humbuckers in a Strat, or another 25.5" inch scale guitar, it sounds twangier than a Les Paul and more like a Fender.

[Steve Conner]

I think the envelope has to be mainly determined by how the string moves relative to the poles.

A pickup has a time constant, sure, but it just manifests as a filter that shapes the frequency response. A filter isn't an ADSR.

Playing the pickup through an overdriven amp complicates things: A good tube amp converts changes in level into changes in timbre in quite a complicated way. It includes about a half dozen time constants that do modulate the signal.

This could make it hard to understand what tonal changes are really to be attributed to the pickup. For example, maybe degaussing the magnets just reduces the output, and the amp then generates less "splatter" on the attack.

So, if I was researching this I would ditch the amp and listen to the pickups through a studio monitoring system.

[fieldwrangler]

I think the envelope has to be mainly determined by how the string moves relative to the poles.

A pickup has a time constant, sure, but it just manifests as a filter that shapes the frequency response. A filter isn't an ADSR.

True, but the transient behavior could be an influence.

Playing the pickup through an overdriven amp complicates things: A good tube amp converts changes in level into changes in timbre in quite a complicated way. It includes about a half dozen time constants that do modulate the signal.

This could make it hard to understand what tonal changes are really to be attributed to the pickup. For example, maybe degaussing the magnets just reduces the output, and the amp then generates less "splatter" on the attack.

This is why I think of all of these elements (pickups, preamps, power amps, speakers, cabs, rooms, etc.) as fundamentally translation devices, which interpret what they take in and pass it on in some new form to the next interpreter.

So, if I was researching this I would ditch the amp and listen to the pickups through a studio monitoring system.

U Buckin' Fetcha. Or even headphones, if you can stand such a thing.

Later on down the line you'll be listening to it through amps, loud, in rooms, in context, etc...

Bob Palmieri

[David Schwab]

I would think the "transient behavior" is from the string/guitar. Scale length plays a big part. Shorter scales aren't as snappy/twangy. Longer scales seem to have more harmonic content.

I have never heard a pickup really changing the attack or sustain on a guitar. Some pickups might seem to have a stronger attack, but I think it's just because it has a resonant peak at the frequency where the string's attack pulse is. However, Leo Fender did use the two poles under the string thing to limit the attack of the string. In his patent he actually had a magnet between each string, including on the outsides. He stated that by softening the attack you would have more apparent sustain. I think this is because the volume levels of the attack and sustain are closer.

[lhpcope]

Hello All,

I'm new to the forum, but I do have a comment. I have a MIK Hamer Standard that came with MIK humbucker pickups. The attack on most all single notes and chords seemed, to my ear, to contain some sort of intermodulation product that was quite unpleasant and unmusical. I tried another set of pickups and was still not happy with the attack of the guitar, even with that brand of made in Asia pickup. I wound a set for myself, and at this point I am very pleased with the attack of the instrument. So for what its worth, it does seem to me that the pickup can change the character of the attack of an instrument. Now I do agree with everyone else that a Humbucker in a Fender still sounds like a Fender.

[salvarsan]

Just a few after-the-fact thoughts here.

Is there a body of knowledge about this stuff? If there isn't much interest, why?

UTFSE. I got 43,500 hits on "ADSR+amplitude+envelope".
There's been interest since the 70's when synthesizers became consumer products.

Is it because you're often still limited to the harsh attack and fast decay of swatting at the strings with a pick

Maybe we like guitars for being guitars instead of something that they are not.

- or maybe because it can all be manipulated electronically, anyway (seen as the domain of electronic effects)?

ADSR and electronic sound manipulation is the purview of music synthesizers and not so much about guitars.

The SynthAxe was a MIDI controller incidentally shaped like a guitar for people jaded from the plucked string sound.
There were only 100 or so made. Owning one was a socioeconomic distinction unrelated to musical prowess, with Alan Holdsworth the outlier, but I digress.

Here, the plucked string is used as a TRIGGER event and the amplitude envelope is configured beforehand according to the performer's skill and taste, or lack thereof.

If you want pitch information, then you accept a 12 millisecond worst case latency conferred by physical laws.
On your average guitar, one cycle of an 82 Hz open low E takes 12 ms.
Faster, cleverer schemes infer pitch from 2nd and 4th harmonic content.

Then, there is MIDI latency.
A minimal MIDI NoteON+pitch message is 4 bytes long.
Clocking out data at 31.5 kHz adds another 1.25 milliseconds.
The latency for a full 6-string chord bothers some players, and the utter inability to do a convincing 'rake' may be a deal breaker.

MIDI 1.0 is mindlessly anachronistic by modern standards, hence several competing audio-over-ethernet/USB/optical standards have blossomed since.

So, Kindly Killer, you want to check the resource links on a MIDI forum like MUSIC FORUM :: Index instead of trolling here.

[Steve Conner]

I'll try to revisit the point I tried to make earlier in a little more detail.

To a first approximation, the envelope of the sound from a pickup is just the envelope of the vibrating string.

To a second approximation, the frequency response of the pickup shapes the attack transient. According to Fourier, fast transients are composed of high frequencies, and large ranges of frequencies. Hence, an overwound pickup, acting as a low-pass filter, may reduce the subjective "attack" of the sound, compared to a hi-fi design with a wide, flat frequency response.

To a third approximation, a guitar string can vibrate in two dimensions: in the plane of the pickup coils and at 90 degrees to them. The two sets of modes are independent ("orthogonal") but there is some energy transfer between them through the bridge, nut and guitar body. The resultant direction of motion of the string can vary all through the duration of the note. It can shift between a line at any angle, an ellipse, a circle, a figure 8 and whatever else it feels like.

The simple mental model we have of a guitar pickup is only sensitive to vibrations at 90 degrees to the coils. But all real pickups will have some sensitivity in the plane of the coils, and the amount of it will differ between different pickup designs. So, different pickups may modulate the envelope of the note differently as the string writhes around.

[Mark Hammer]

Let us not ignore the bridge system. Remember that what the pickup detects, or can detect, whether in terms of frequency content, or amplitude, is constrained by what the string is delivering. Not only does string length/scale and tension impact heavily on that, but so does the bridge system, and the extent to which the guitar "supports" sustain and harmonics after the initial attack.

For years, folks have been attempting to nail the distortion sounds used in funk, Motown, and soul recordings, and they tend to fail miserably. Why? Because a lot of those recordings were made by session folks using big jazz boxes with wooden floating bridges. The drop in harmonic content after the initial pick attack tends to be rather substantial on those. Throwing a distortion on it gives the distortion something very different to work with than throwing a distortion on a solid body with a firmly-anchored bridge, even though the string length/scale, gauge, and tension may be identical. In effect, the construction of the instrument, and accompanying bridge system, already provides a distinct envelope. That's why big body jazz boxes have a more percussive feel than solid-bodies.

None of this is to suggest that pickups and specific magnet types or polepiece designs could NOT have any influence in amplitude envelope. Rather whatever impact they have would be thrown into the hopper with what the guitar construction and the string properties also contribute. That's gonna be a tough one to surgically separate.

[Mike Sulzer]

Let us not ignore the bridge system.

Very good point. Even the bridge systems on solid bodies can make a real difference. TOM + tailpiece is nothing like a low flat tele. Even a combination one piece TOMandTail is different from two separate.

[dor baruch]

from the experiments that i conducted with ADSR of electric guitars
It turns out that the ADSR of a given guitar When all variables are equal and the only variable is the pickup type and the distance itself from the Vibrating String
is that the time is constant in all the pickup types from the attack to the Decay-Sustain-Release and the only variable is the amplitude of Each one

You can modify your guitar ADSR even strumming with a different strumming Methods and the type of material that you strumming with
(amplitude and time)
ADSR as a concept is time based and i think its Not entirely suitable for examining the guitar sound or the pickup Behavior

[Mike Sulzer]

To a second approximation, the frequency response of the pickup shapes the attack transient.

Yes, the high frequencies are damped quickly, and so they are important for the attack and decay. In fact "ADSR" is kind of artificial: the A and D go together as the transient. I think the reason that they are separated out is that one way to synthesize a signal is to construct a set of fundamental and overtone ratios and then complete the sound by modulating them. You need to specify both attack and decay since this is something you are imposing on the signal, not something you are just letting happen. (About 35 years ago I thought a different way to make a synthesizer would be to solve the differential equation describing an instrument, be it real (and thus approximating reality at some level) or artificial (and capable of "unreal" sounds). Then the ADS would just happen, and you would have a related equation for the R. Computers are probably just about up to doing this now.)