Compression and sustain in a pickup?

Artie

Peaveyologist
I think I have a reasonably good understanding of how a pup works, but these two things elude me. I see these two terms used all of the time to describe pup characteristics.

Sustain: My understanding is that sustain refers to how long a string "rings out". I can see where every part of the guitar, except the pups, would affect this. The pickup just detects, and sends out, anything the strings are doing. I don't understand how a pickup contributes to how long the string vibrates.

Compression: I think of compression as a purely electronic function. Not sure how a pickup adds to it.

I'm not saying a pickup doesn't. Just hoping someone can help me understand how they do. Am I reading too much into this? Are these just words to describe "flavor"? Kinda like saying a pickup is "warm"?

Artie
 
Re: Compression and sustain in a pickup?

Agreed. Sustain is a mechanical thing. Pickups can only directly affect sustain when adjusted so close to a string as to interfere with excursion. Compression is an intentional reduction of dynamic range. Arguably, any imperfect transducer can be accused of this.

EDIT - It is tempting to quote Itsabass from a recent thread in The Bassment room. "People are idiots."
 
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Re: Compression and sustain in a pickup?

I'd think mebbe a higher output p/up would catch more of the decay

I dunno,carry on...
 
Re: Compression and sustain in a pickup?

Higher resistance pickups offer a more compressed sound, so yes, pickups can affect compression.
 
Re: Compression and sustain in a pickup?

Higher resistance pickups offer a more compressed sound, so yes, pickups can affect compression.

But how? Compression is where you suppress a loud signal, then amplify a softer signal so that the volume tries to remain at an even level. How would a "hot" pickup suppress its initial attack?
 
Re: Compression and sustain in a pickup?

Well, some of the high output pickups roll off the mids/top-end frequencies....and these tend to be the things that come through with hard playing. Also they generate such a signal that the dynamics of playing tends to be lost, which also could be labelled as compression.
 
Re: Compression and sustain in a pickup?

To my thinking, those two things are dependent on pickup output. Higher output pickups (i.e. pickups that create more voltage => more current) hit an amp with more stuff. This causes more compression in the final sound (not "in the pickup") than a low output pickup at the same amp settings. Sustain would be longer because higher output pickups have a lower threshold for picking up string vibration at an audible level. That is to say, the higher output pickups are more sensitive to string vibration. An amount of vibration that would not create an audible note with a lower output pickup does create an audible note with the higher output pickup. Therefore, sustain will of course be longer.

External factors matter as well. For instance, high output pickups may tend to be used at higher volumes, which can contribute to prolonged vibration of the strings. Sustaining notes at high volumes will increase the sustain even more, by way of the sound in the room keeping the string vibrating.

My uneducated guesses, anyhow.
 
Re: Compression and sustain in a pickup?

Higher output pickups (i.e. pickups that create more voltage => more current) hit an amp with more stuff. This causes more compression in the final sound (not "in the pickup") than a low output pickup at the same amp settings.

That's a pretty good uneducated guess. :D

That makes the most sense to me. That the compression is actually happening farther down the line, as a result of a higher output pickup.

I'll buy that. :)

Artie

Edit: BTW, these STK's seem to be some of the most sensitive pups to pickup height that I've ever used. Too high, or too low, and they sound weird . . . "metalicy". But when you find the sweet spot, they're suweeet!
 
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Re: Compression and sustain in a pickup?

I think I have a reasonably good understanding of how a pup works, but these two things elude me. I see these two terms used all of the time to describe pup characteristics.

Sustain: My understanding is that sustain refers to how long a string "rings out". I can see where every part of the guitar, except the pups, would affect this. The pickup just detects, and sends out, anything the strings are doing. I don't understand how a pickup contributes to how long the string vibrates.

Compression: I think of compression as a purely electronic function. Not sure how a pickup adds to it.

I'm not saying a pickup doesn't. Just hoping someone can help me understand how they do. Am I reading too much into this? Are these just words to describe "flavor"? Kinda like saying a pickup is "warm"?

Artie

I'm not sure if this has already been said in finer words, but surely stronger magnets would dampen the string's vibration faster. I think I've heard the term "string pull". That's Lace's explanation for why you typically see more sustain from their "low string pull" pickups. Putting a big magnet by a moving piece of steel wire will attract it, putting tension on it, helping to stop movement.

As for compression its probably a lot to do with how the pickup effects your other gear, you'd get quite a compressed sound putting a super distortion (am I allowed to say those words on this forum?) pickup through a tweed champ.

In old school methods though if you get a more powerful pickup you'll probably see more sustain because you'll be playing louder and running your amp into overdrive, despite the greater string pull of the stronger magnets.

Having said that. Angus Young always got good sustain out of his pickups and if they were standard (on the early DC records) then they would likely have been quite low powered and unpotted (as has been mentioned) helping to get feedback from that old JTM head. I've found it helps to get that lovely singing sustain if you have a valve rectifier too.
 
Re: Compression and sustain in a pickup?

Disclaimer I guess this will be an applied physics type of story, so just skip this post at will ;).

I quess any amplifier has a maximum output and the same goes for transducers (that much is true at least from a physics point of view). For most transducers there comes a point where they do not respond linearly to an increase in energy anymore (sound waves in our case). The (negative) deviation from linearity is percieved by our ears as compression. For instance a microphone has some point it will start to compress or distort (although with a mic you may never reach that point, just saying it could happen). The same principles apply to our pickups, I just don't know if the onset of this effect will be in the range of our use of a pickup. My guess is that we do hear it with high output pickups. There are two issues, one is getting near to the absolute limit (you cannot get more energy out of a transducer than the energy you originally had), I guess we are not near that limit, but the other limit is more important. We all know that more windings shifts the resonance peak to the left (if all other things are equal). That means all of the signal above the resonance peak gets compressed more. So in effect the pickup will sound more compressed with more windings. Even though you may flatten out the EQ of the pickup a bit more by combining magnets and winding types and gauges etc., fact remains that also internal to a pickup there is some compression possible. And the higher the output of the thing gets, the more 'risk' of compression. I don't know if pickups get much into this territory, but some tests with a pickup and an oscilloscope could tell you a little bit about it.

Since compressors increase sustain, so will pickups with more compression seem to be more sustaining.

Is the pickup the biggest source of compression: no way, any gain stage near its limits will compress and in our amps and pedals we have lots of them...

Maybe someone with a twin (on low volume) can test one extreme high output humbucker and vary the picking intensity. And next replace it with a very low output pickup and vary picking intensity. When you compare the dynamic range between the pickups you can say something about the compression going on. My feeling is that there are some pickups that are way more sensitive to picking dynamics than others. The insensitive ones we would call compressed I guess...
 
Re: Compression and sustain in a pickup?

That's a pretty good uneducated guess. :D

That makes the most sense to me. That the compression is actually happening farther down the line, as a result of a higher output pickup.

I'll buy that. :)

Artie

Edit: BTW, these STK's seem to be some of the most sensitive pups to pickup height that I've ever used. Too high, or too low, and they sound weird . . . "metalicy". But when you find the sweet spot, they're suweeet!

Yeah that's it. Other guys said that already. HO PUS have the compression effect in conjunction with the amp and also at kind of high gain settings (MrTondo also has a point there about tranducer output too). High output pickups hit the amp rails faster and for more time keeping the note at constant level for the most of its duration. There you have compression.

In fact compression and sustain are one and the same when it comes to one note. Sustain is compression and compression is sustain if you think about it.
Higher output pickups pick up more of the note as it fades off and can hold it (with the help of the amp) almost at the same volume throughout. That gives compression.

Now fast attack is also a compression aspect. Not strong attack but fast attack. Again high output pickups reach the maximum volume of an amp on a distorted channel faster because of it's output once again. Even the attack has its envelope, beginning with lower amplitude (it just happens fast). With high output pickups happens faster. High output pickups never have strong attack, they have fast attack.

Strong attack is a characteristic of a loose sound. Because you have a strong beginning of the note that fades out fast (low output pickup effect). But that's good with low gain or clean channels because it is more expressive. There it's mostly the player that determines how long and how loud the note is with his playing.
 
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Re: Compression and sustain in a pickup?

Sustain is more related to the construction of the guitar... The best test of sustain is using an unplugged guitar and seeing how long the note will ring without amplification... As mentioned above, pups can benefit or hurt sustain, but they can't increase an instruments natural sustain, only amplify the decay of the signal...

Compression is more of an amplifier or FX trait. We all no wait a compressor/sustainer will do, so let's skip that one... An amp can be built so as to have compression like traits... It will raise a weak signal, but the architecture can be designed so as to "squash" the hard attacks on strings. Not necessarily intentional, but organic nonetheless...
 
Re: Compression and sustain in a pickup?

I would guess that active pickups can cause compression when the dynamic limits of the internal preamp are exceeded
 
Re: Compression and sustain in a pickup?

I've been thinking about this, specially the sustain bit for a while. I've always liked one pickup guitars, all the way from Esquires to Les Paul Jrs to single humbucker shredsticks like the RG2610. Sure, there's a design philosophy I gel with, but at the same time, I've always felt a difference from playing an Esquire and a Tele on the lead pickup. I've never had the chance to try it out but I've always wanted to grab a Tele, a Les Paul Special, a regular RG, etc and just play them with the neck pickups installed, record them, then remove the neck pickups, stuff the cavities or put blank pickguards in (so feedback doesn't play a part in it), record again and just random AB them to see if I can hear any difference without the extra magnet pull.

But then again, I'm too lazy, I'd rather just play the damned things. I'm sure the difference (if there's any) isn't much anyways.
 
Re: Compression and sustain in a pickup?

As for compression its probably a lot to do with how the pickup effects your other gear, you'd get quite a compressed sound putting a super distortion (am I allowed to say those words on this forum?) pickup through a [redacted].

No you can't; mentioning a t***d c***p round here is a bit of a no-no. You'll probably pick up an infraction for that...
 
Re: Compression and sustain in a pickup?

This is a classic forum/internet real-life example of what happens when we interchange the 'literal' physical definition or properties with the same word as a tonal description. Both are correct.

Sometimes describing a pickup as 'compressed' is useful and accurate. Its not complete, but it can be useful in a real-life, real-time attempt at describing something as ineffable as tone. It describes a 'less open' sound. Compression in general reduces dynamics and from a tonal point of view reduces the natural open transients. So 'compressed' is sometimes a great word choice.

'Sustain' is also accurate as part of a pickup characteristic description in some cases. This is particularly relevant when you are swapping out pickups. If it were guitar/build/setup only, then the guitar would sustain the same while plugged in no matter which pickups you use. This is never the case. Some pickups/magnet strength, style, design voodoo (whatever) provide greater sustain in a particular guitar versus another. Try 20 different pickup sets in the same guitar. Its very evident.

This is why we see some people say that the 'XXX' pickup sounds thin and weak and other say the 'XXX' sounds full and complex. Both are correct.

The whole tonal gig is an interaction. Its a holistic chain All of it. It must eventually all be view/assessed/recommended etc. with that in mind for it to be of any real service IMO.

Cheers and respect,

RG


I think I have a reasonably good understanding of how a pup works, but these two things elude me. I see these two terms used all of the time to describe pup characteristics.

Sustain: My understanding is that sustain refers to how long a string "rings out". I can see where every part of the guitar, except the pups, would affect this. The pickup just detects, and sends out, anything the strings are doing. I don't understand how a pickup contributes to how long the string vibrates.

Compression: I think of compression as a purely electronic function. Not sure how a pickup adds to it.

I'm not saying a pickup doesn't. Just hoping someone can help me understand how they do. Am I reading too much into this? Are these just words to describe "flavor"? Kinda like saying a pickup is "warm"?

Artie
 
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