UST QUACK! - Okay, now I understand - UPDATED

[Methos1979]

For years I've heard/read here about the phenomenon of UST (Under Saddle Transducer) pickup quack. But because I've never owned one (at least not for very long) I never really noticed it. Even when others commented on a recorded live performance and complained about the quack it never seemed something to stood out to me. Nearly all of my guitars over time have had SBT pickups in them. Or at least multi-source. Recently I picked up a couple RainSong guitars which have an LR Baggs Element StagePro and Anthem StagePro systems in them.

The newest one with the Anthem seems particularly prone to quack. And now that I've heard it, I get it. And now I can't unhear it! Quack seems to be a direct result of string buzz that comes from a poorly fretted note or a string hit too hard which causes the string to buzz/vibrate against an adjacent object like your finger or a fret which is then transferred directly to the pickup via the saddle. As opposed to a SBT (Soundboard Transducer) pickup which derives its signal from the vibrating soundboard so no, or at least less quack.

And yes, it's annoying. The good news is that it is forcing me to be a much better player, to be more cognizant of playing more accurately and with the right amount of force. I now consider it as much a personal failure when I quack as when a flub a chord. I really like the Anthem StagePro now that I'm used to it. I wonder if anyone has ever tried to convert an Anthem system over to using an SBT in place of the UST. Seems like it would be the best of both worlds.

UPDATE: There was a lot of great feedback (pun intended) from various posters replying to this thread - thanks for that. Yes, the buzzing from poor technique is definitely a different animal than quack, strictly speaking. However, even when played with very good technique the quack was still very apparent at higher gain (as set on the Anthem StagePro preamp) when any sort of attack was used. This became very much apparent on the few songs that are played primarily fingerstyle but at some point (usually in a chorus) I would need to strum. Paul Simon's '50 Ways To Leave Your Lover' is a good example of this.

But wait, what I didn't factor into this was that I'm an idiot. (Hey, if it looks like a duck and quacks like a duck... pun intended again!) I discovered today (two months into playing the guitar in question) that I was not using the onboard Anthem StagePro piezo(UST)/mic blend slider correctly. What I assumed to be blending in the maximum amount of mic was in fact instead just the opposite - blending in nothing but UST piezo. In this position combined with bumped up trebles to enhance fingerstyle playing, I was in effect setting up the guitar to provide maximum quack with minimum attack! DOH!!

Hey, at least I caught it before I went live with this guitar in a couple weeks! Turns out there's little symbols right on the slider that clearly shows slider up as piezo (PZ) and slider down as mic (picture of a mic). At least I got a couple months of deliberate technique improvement motivation which actually has paid off! So while quack is definitely a real thing, and something I'm now more acutely aware of than ever before, at least I can now dial out almost completely and this RainSong Nashville OM continues to get better and better as a gigging guitar. I'm excited to use it in the coming weeks for our first post-pandemic live shows.

[fazool]

Originally Posted by Methos1979

...And now that I've heard it, I get it. And now I can't unhear it!

Yep - exactly!

I have become hyper-over-sensitive and totally intolerant of piezo quack.

Some people have "perfect pitch" and can naturally hear the notes. I have "perfect quack" - I can hear a quack whisper at a hundred yards -it's almost physically distressing to me.

And I can't get beyond that......

Originally Posted by Methos1979

...Quack seems to be a direct result of string buzz that comes from a poorly fretted note or a string hit too hard which causes the string to buzz/vibrate against an adjacent object like your finger or a fret which is then transferred directly to the pickup via the saddle. As opposed to a SBT (Soundboard Transducer) pickup which derives its signal from the vibrating soundboard so no, or at least less quack.

It may be triggered or activated or enhanced by playstyle but no, quack is entirely 100% an electrical signal phenomenon. Soundboard transducers operate as flexural piezoelectric elements while UST's operate as compressive piezo powder (pressed loosely into shape in a retaining jacket or fire into shape). They operate differently.

The quack is caused by the changing capacitance of the piezo material dynamically filtering the mid frequencies - making for a very "nasal" tone.

[Petty1818]

What's funny is that when I started playing guitar back in 2000, I remember watching Clapton live videos and literally loving his acoustic guitar tone. It was a basic Fishman Matrix that would quack like crazy when he would dig in. I thought it was great and actively searched out that tone. Once I heard more natural pickups, I couldn't stand the quack any longer.

[Doug Young]

Originally Posted by Methos1979

And now that I've heard it, I get it. And now I can't unhear it!

Yep, and I think that's true of many pickup sounds - even aside from quack, many pickups have a certain distinctive sound that alerts you to it not being acoustic. Once you hear it, it's hard to ignore. The Element UST has a sound that often bothers me.

Quack seems to be a direct result of string buzz that comes from a poorly fretted note or a string hit too hard which causes the string to buzz/vibrate against an adjacent object like your finger or a fret which is then transferred directly to the pickup via the saddle.

I don't think that's the source of quack, but it is somewhat avoided with a lighter touch. Less of an issue for fingerstyle than hard strummers, for example.

I wonder if anyone has ever tried to convert an Anthem system over to using an SBT in place of the UST. Seems like it would be the best of both worlds.

I haven't tried that, but I and some others, if I recall, have tried K&K+Lyric, which would be similar. In the end, I didn't care for it, I'd prefer K&K+standard mic, but your mileage could vary. One issue is that the optimal placement for K&Ks and the recommended TruMic placement are the same spot - right under the saddle line, so you have to compromise somewhere.

[AeroUSA]

Originally Posted by Methos1979

For years I've heard/read here about the phenomenon of UST (Under Saddle Transducer) pickup quack. But because I've never owned one (at least not for very long) I never really noticed it. Even when others commented on a recorded live performance and complained about the quack it never seemed something to stood out to me. Nearly all of my guitars over time have had SBT pickups in them. Or at least multi-source. Recently I picked up a couple RainSong guitars which have an LR Baggs Element StagePro and Anthem StagePro systems in them.

The newest one with the Anthem seems particularly prone to quack. And now that I've heard it, I get it. And now I can't unhear it! Quack seems to be a direct result of string buzz that comes from a poorly fretted note or a string hit too hard which causes the string to buzz/vibrate against an adjacent object like your finger or a fret which is then transferred directly to the pickup via the saddle. As opposed to a SBT (Soundboard Transducer) pickup which derives its signal from the vibrating soundboard so no, or at least less quack.

And yes, it's annoying. The good news is that it is forcing me to be a much better player, to be more cognizant of playing more accurately and with the right amount of force. I now consider it as much a personal failure when I quack as when a flub a chord. I really like the Anthem StagePro now that I'm used to it.

I wonder if anyone has ever tried to convert an Anthem system over to using an SBT in place of the UST. Seems like it would be the best of both worlds.

Stay out of those rabbit holes Methos!!!

[MrErikJ]

Originally Posted by Methos1979

I wonder if anyone has ever tried to convert an Anthem system over to using an SBT in place of the UST. Seems like it would be the best of both worlds.

I do believe someone on the forum did try that but I can't recall who.

I think it's also important to note that, with the Anthem, the UST is intended to be used very specifically. While you can dial it in to carry the majority of frequencies, its purpose is to handle ultra-low lows and be feedback resistance. I've heard that the Anthem's sweet spot is to dial in max-mic and then dial back just a tiny bit. The Anthem SL is preset at that "sweet spot" where the mic carries most freqs and the Element just the lowest ones.

The problem with the K&K or some other SBT in the spot of the Element is that they require the same location to function (the Tru-Mic is a microphone operating as a SBT) and you'd lose the feedback resistance a UST offers. You could, theoretically, use another UST that you prefer or a magnetic pickup. I think the best sounding USTs are usually the unitary saddle designs, like the Barbera Soloist or the Baggs LB6. However, those pickups are both more difficult installs (the reason I no longer use the LB6) and have mixed phase piezo elements that may not work well in a crossover circuit. I'm not sure if I entirely believe that as plenty of folks have mixed LB6s and Soloists with internal mics (including Baggs in the Duet, Dual Source, and Godin Doyle Dykes Multiac) but it's definitely possible there could be phase cancellation.

Anyway, long story short, I also don't love the Element but there's a reason Baggs uses it in that configuration: it most easily solves the tone/functionality conundrum.

[Chriscom]

Originally Posted by fazool

It may be triggered or activated or enhanced by playstyle but no, quack is entirely 100% an electrical signal phenomenon...

That's my understanding. I've long been disappointed by the quacky Sonitones in my two gig guitars, a problem that is more than tamed to my satisfaction by the ToneDexter (tale for another day). But a couple of local musicians like to play my guitars when we happen to meet at jams, and I'm always struck by how good they sound without any high-tech help, just the Sonitone signal through the modest house PA. And I think the key, which is part of their all-around higher level of musicianship, is they don't try to murder the strings the way I slide into too often. They were playing Use Me (Bill Withers) and the guy playing the bass-y line on my GPRS1 sounded great and surprisingly acoustic.

[shufflebeat]

Originally Posted by Methos1979

...Quack seems to be a direct result of string buzz that comes from a poorly fretted note or a string hit too hard which causes the string to buzz/vibrate against an adjacent object like your finger or a fret which is then transferred directly to the pickup via the saddle.

There are two separate issues that I associate with early attempts at piezo amplification.

One is the "quack" which is the result of several phenomena. My amateur explorations over the years would suggest that if you were to take a decent guitar sound, strip away the sound of pick on strings and somehow do away with the influence of the soundboard you'd end up with something quite "quacky" which is then exacerbated as described previously.

The other one is the "broken glass" or "bag of spanners" sound which is how I characterise the string rattle you describe very accurately. I found Ovations to be Public Enemy #1 in this regard, partly because of the nature of the pickup but also because they often achieved an admirably low action which made them great to play and horrible to amplify. Somehow Takamine managed to avoid the worst of the razor blades.

Thankfully we now have the technology to deal with this to a great extent (thank you, James) but unfortunately not everyone is on the same quest.

As far as, "once you've heard it..." I have a visceral aversion to magnetic pickups on my own guitars but I have heard others make nice(ish) noises with them.

...kind of.

[Methos1979]

Originally Posted by fazool

The quack is caused by the changing capacitance of the piezo material dynamically filtering the mid frequencies - making for a very "nasal" tone.

Interesting! I never really knew the answer, just my own thoughts as to why. Nice to have a more definitive, technical reason.

Originally Posted by Doug Young

I haven't tried that, but I and some others, if I recall, have tried K&K+Lyric, which would be similar. In the end, I didn't care for it, I'd prefer K&K+standard mic, but your mileage could vary. One issue is that the optimal placement for K&Ks and the recommended TruMic placement are the same spot - right under the saddle line, so you have to compromise somewhere.

Funny thing is, when I was wondering if someone had tried this swap, my mind immediately went to you, Doug!

Originally Posted by AeroUSA

Stay out of those rabbit holes Methos!!!

LOL! Says the guy that digs these holes for us with his awesome reviews!!!

[Doug Young]

Originally Posted by Methos1979

Funny thing is, when I was wondering if someone had tried this swap, my mind immediately went to you, Doug!

Here's the thread from when I did this (from 2013)

https://www.acousticguitarforum.com/...d.php?t=289058

[AeroUSA]

Originally Posted by Methos1979

Interesting! I never really knew the answer, just my own thoughts as to why. Nice to have a more definitive, technical reason.



Funny thing is, when I was wondering if someone had tried this swap, my mind immediately went to you, Doug!



LOL! Says the guy that digs these holes for us with his awesome reviews!!!

I’m trying to fill the holes!

[James May]

Oh yes, quack. It is true that once you hear it you can't unhear it. It's a bit like catching a glimpse of the man behind the curtain, which of course marketing departments don't want you to do.

A point of clarification about the cause of quack. Ceramic Piezo crystals are just as linear when operating in compression mode as they are when operating in bending mode. In fact, as far as the atoms are concerned, they are the same thing.

The source of quack is actually pretty simple. A UST mainly hears the strings with very little body sound. In fact, quacky is what strings actually sound like without the benefit of much guitar resonance. That's why I'm a huge fan SBTs when done right.

[shufflebeat]

Originally Posted by James May

In fact, quacky is what strings actually sound like without the benefit of much guitar resonance.

...or pick "slap", or room.

[/pedantry].

[Brent Hahn]

One thing that can help is having a very-high-impedance preamp be the first thing the pickup hits. That seems to both remediate the quack itself (a bit) and let more "attack thump" though, which can sort of distract your ear away from the quacky aspect. Unfortunately, most UST guitars come pre-packaged with a crummy preamp so you get what you get and no further electronics will really help.

The outboard preamp K&K sells for their passive Mini isn't the best of the best, but it's still a lot better than any barndoor preamp and it's only a hundred bucks or so. But you have to reroute your UST directly to the output jack to use it.

[varmonter]

Originally Posted by shufflebeat

There are two separate issues that I associate with early attempts at piezo amplification.

One is the "quack" which is the result of several phenomena. My amateur explorations over the years would suggest that if you were to take a decent guitar sound, strip away the sound of pick on strings and somehow do away with the influence of the soundboard you'd end up with something quite "quacky" which is then exacerbated as described previously.

The other one is the "broken glass" or "bag of spanners" sound which is how I characterise the string rattle you describe very accurately. I found Ovations to be Public Enemy #1 in this regard, partly because of the nature of the pickup but also because they often achieved an admirably low action which made them great to play and horrible to amplify. Somehow Takamine managed to avoid the worst of the razor blades.

Thankfully we now have the technology to deal with this to a great extent (thank you, James) but unfortunately not everyone is on the same quest.

As far as, "once you've heard it..." I have a visceral aversion to magnetic pickups on my own guitars but I have heard others make nice(ish) noises with them.

...kind of.

Magnetic like piezo have there own distinct sound.. I like mag pups for their live performance capabilities.
Feedback resistance at volumes that
will make piezos howl. Pickups on acoustics in any form are a compromise over a mic. They all impart a change in our acoustic tone.
Its only us musicians that climb down this rabbit hole.
The audience for the most part could care less..
Ask a question on this forum like
"What is the best wiz bang preamp box for my acoustic" And if 50 people
respond you'll likely have 50 different
answers. This tells you why "my guitar only louder" is a myth.