The Physics of "mwah"?

[fretlessman71]

Currently looking for a resource that goes into detail about what creates the fretless mwah. I'm after the math/physics aspect of it; hardness of wood, action/neck angle/fingerboard angle, how tension of strings relates to it, that sort of thing. Is there a book or a website I should go to? No luck finding anything on my own yet.

 

[FugaziBomb]

lower action and fretboard material hardness will effect that the most

 

[Deak]

Sub'd for the science and math part of which I have none to offer ATM, but on my portamento, the closer to the neck or even on the neck defines how much Mwah I can produce on it.

 

[bkbirge]

I would guess it's primarily a function of string damping and component of string amplitude that is perpendicular to the fretboard. I'd start by modeling a fixed-fixed spring in 3d coords and try different initial impulse vectors at different points along the spring. Then move onto modeling damping effects of the fingerboard maybe.

 

[byacey]

What creates the sound is the portion of the string close to the end where the note is being stopped against the fingerboard, slapping against the fingerboard as it vibrates. This creates the mwah distortion sound.
The lower the action, the more pronounced the effect.
As for timbre created by different fingerboard materials and strings, I don't have much to offer.

 

[GretschWretch]

This probably will provide nothing to answer your question, but it still is an interesting read.

Invalid Link Removed

 

[mikeswals]

the string is also contacting a flat surface -more area- vs the tippy top of a fret crown.

 

[eastcoasteddie]

What creates the sound is the portion of the string close to the end where the note is being stopped against the fingerboard, slapping against the fingerboard as it vibrates. This creates the mwah distortion sound.
The lower the action, the more pronounced the effect....

This and the use of roundwound strings.

 

[byacey]

What creates the sound is the portion of the string close to the end where the note is being stopped against the fingerboard, slapping against the fingerboard as it vibrates. This creates the mwah distortion sound.
The lower the action, the more pronounced the effect.
As for timbre created by different fingerboard materials and strings, I don't have much to offer.

This and the use of roundwound strings.

I have flats on mine, and it still produces that sound.

 

[Element Zero]

I would guess it's primarily a function of string damping and component of string amplitude that is perpendicular to the fretboard. I'd start by modeling a fixed-fixed spring in 3d coords and try different initial impulse vectors at different points along the spring. Then move onto modeling damping effects of the fingerboard maybe.

Right over my head.

 

[Matthew_84]

I have flats on mine, and it still produces that sound.

I think rounds accentuate the tone though, just like emphasizing the bridge pickup does, IME.

String tension also plays a role - that’s why you get more of it if you play closer to the middle of the string (over fingerboard) then near the end (bridge).

 

[Rumbledore]

The vibrations of a played string dampens into your finger meat

Mwah is because your squishy finger on the string against the fretboard causes a characteristic decay, different than when fret

 

[Sid Fang]

On a fretless fingerboard, or a sitar bridge, instead of having the usual clearance for string vibration between fret/nut and bridge, one end of the string approaches the finger/bridge at a very gentle angle. Vibrations running down the string will, with a probability depending on their frequency and phase, encounter the slope before they hit the string termination, causing some of the energy to be absorbed, and some of it to be converted into reflections sent back down the string that may not be exactly a multiple of the fundamental frequency. Peeowww. Mwwwah.

 

[Drucifer]

I think rounds accentuate the tone though, just like emphasizing the bridge pickup does, IME.

String tension also plays a role - that’s why you get more of it if you play closer to the middle of the string (over fingerboard) then near the end (bridge).

Beat me to it, the mwah(sp?) sound definitely is higher frequency, so the bridge pickup and roundwound strings and treble EQ accentuate it.

 

[chadds]

It’s for me a slight lifting of the “fretting” finger allowing larger string vibration against fingerbd.

 

[JRA]

the string hits the board while it's vibrating.

 

[Bunk McNulty]

"Mwhah" is what the girls say when they give you a kiss while holding an iPhone.

 

[BasementWarrior]

I have no idea what you’re talking about. I thought this thread was going to be about envelope filters.

 

[Jeff Scott]

I have flats on mine, and it still produces that sound.

I prefer the mwah (kiss) I get with TI JFs on my fretless over the tone I got with rounds on it.

 

[Bruce Johnson]

We've had many, many threads here on TalkBass discussing mwah. Mostly in threads about fretless fingerboard resurfacing. Search for the word Mwah. That's what we call it around here.

Here's one post that I wrote in 2014 that covers it pretty well:

Yep. The Mwah sound is really just accurately controlled buzz.

First, the fingerboard needs to "True". It doesn't necessarily have to be flat; that is, it can have some relief. But the surface cannot have any ripples or lumps. That's what "True" means.

Then, you lower the action down to the point where it just begins to buzz, under your normal playing. This will depend on your own playing technique. You want it right where it doesn't buzz when you pluck lightly, and buzzes evenly when you pluck hard.

You can get the Mwah sound with any fingerboard wood or fingerboard surface. Harder woods and hard surfaces will make the buzz brighter sounding; more high end in it.

Same with the strings. Flatwounds can Mwah with a warmer, deeper buzz. Roundwounds will usually be brighter, more highs.

From there, you control the volume of the Mwah on each note with how hard you pluck, and the duration of the Mwah with rolling the left hand finger.

It's a combination of careful setup and accurate playing technique.

The above is from this thread:
What Makes the Mwah sound on a Fretless?
​