PUNCH! How do we define it?

[svart-hvitt]

Everybody talks about punch but few take the time to define it. Is punch an audiophile term only, too vague to have a meaning? Or can we use audio science and engineering insight to fill the term with meaning?

In a previous thread (https://www.audiosciencereview.com/...speakers-in-particular-speaker-dynamics.7742/) competent and experienced speaker designer Klaus Heinz talked about «dynamics», which sounds (sic!) related to punch. Despite Mr. Heinz’s vast experience, he isn’t able to define «dynamics» and describe it using a formula.

Our member and gear designer @March Audio recently wrote the following about his new amplifier:

«...these NC1200 modules have some serious punch».

Are @March Audio ’s words just marketing fluff, or is he using a word that makes sense to him despite not being able to define the term?

In the latest JAES, there’s an article devoted to the term, «A Perceptual Model of "Punch" Based on Weighted Transient Loudness»:

http://www.aes.org/e-lib/browse.cfm?elib=20484

Authors Fenton and Lee write: «Punch is an attribute that is often used to characterize music or sound sources that convey a sense of dynamic power or weight to the listener».

The AES article has a literature section that makes it clear that «punch» is NOT a term without content, and many researchers have previously written about the subject. So one cannot wave off the term as pure marketing fluff; there’s something to the term that audio interested people care about.

The AES article deals with punch in recorded material. However, Heinz and @March Audio use the term related to audio gear. So I suggest this path of inquiry when discussing the term «punch»:

(1) Punch in recorded material
(2) Punch reproduced by audio gear

I had primarily gear (2) in mind when I made this thread, but it may be hard to skip any references to recorded material (1)? So feel free to discuss both (1) and (2). For some reason, it seems like most if not all of the AES articles on punch are related to (1).

To start off the discussion, I had a handful of questions in mind:

(a) What does it take make sound with punch? Can we have punch in headphones, in desktop and bookshelf speakers, or does size matter?
(b) Is punch related to speakers only, or can DACs and amplifiers have punch?
(c) Is punch related to SPL? Can we have punch only if sound pressure levels are high?
(d) Is punch related to lower frequencies only, or can a tweeter be «snappy» and have punch?
(e) Are highly efficient (say 120 dB/1W) compression drivers more «punchy» than other driver designs?

Don’t let these questions limit the discussion and feel free to express any thoughts and critique you may have related to the term «punch»

 

[Cosmik]

Without listening to any music or equipment, I will say that if the step response isn't a step because of timing and phase misalignment, and if the speaker includes any additional wheezing resonator device (takes time to get going and time to stop) its 'punch' will be compromised.

We people with sealed, DSP, phase-corrected, active, time aligned speakers take punch for granted and sometimes forget that not everyone is so fortunate.

 

[svart-hvitt]

Without listening to any music or equipment, I will say that if the step response isn't a step because of timing and phase misalignment, and if the speaker includes any additional wheezing resonator device (takes time to get going and time to stop) its 'punch' will be compromised.

We people with sealed, DSP, phase-corrected, active, time aligned speakers take punch for granted and sometimes forget that not everyone is so fortunate.

I listened to Kii (a speaker which is an answer to your criteria), and it left much to be desired.

I listened to Kii BXT, and it was like a new, punchier speaker (though its vertical directivity reveals flaws as you stand up and walk in the room).

The main difference between Kii and Kii BXT is a tripling of the speaker footprint.

On phase, @Floyd Toole wrote:

«An enormous amount of evidence indicates that listeners are attracted to linear (flat and smooth) amplitude vs. frequency characteristics; more to be shown later. Figure 7 in Toole (1986) and the excerpts shown here in Figure 5.2 indicate that listeners showed a clear preference for loudspeakers with smooth and flat frequency responses. Figure 5.2 also shows phase responses for those same loudspeakers. It is difficult to see any reliable relationship to listener preference, except that those with the highest ratings had the smoothest curves, but linearity did not appear to be a factor. Listeners were attracted to loudspeakers with minimal evidence of resonances because resonances show themselves as bumps in frequency response curves and rapid up-down deviations in phase response curves. The most desirable frequency responses were approximations to horizontal straight lines. The corresponding phase responses had no special shape, other than the smoothness. This suggests that we like flat amplitude spectra, we don’t like resonances, but we seem to be insensitive to general phase shift, meaning that waveform fidelity is not a requirement.»

So it seems like your opinion is not supported by Toole’s research?

 

[Cosmik]

I listened to Kii (a speaker which is an answer to your criteria), and it left much to be desired.

I listened to Kii BXT, and it was like a new, punchier speaker (though its vertical directivity reveals flaws as you stand up and walk in the room).

The main difference between Kii and Kii BXT is a tripling of the speaker footprint.

On phase, @Floyd Toole wrote:

«An enormous amount of evidence indicates that listeners are attracted to linear (flat and smooth) amplitude vs. frequency characteristics; more to be shown later. Figure 7 in Toole (1986) and the excerpts shown here in Figure 5.2 indicate that listeners showed a clear preference for loudspeakers with smooth and flat frequency responses. Figure 5.2 also shows phase responses for those same loudspeakers. It is difficult to see any reliable relationship to listener preference, except that those with the highest ratings had the smoothest curves, but linearity did not appear to be a factor. Listeners were attracted to loudspeakers with minimal evidence of resonances because resonances show themselves as bumps in frequency response curves and rapid up-down deviations in phase response curves. The most desirable frequency responses were approximations to horizontal straight lines. The corresponding phase responses had no special shape, other than the smoothness. This suggests that we like flat amplitude spectra, we don’t like resonances, but we seem to be insensitive to general phase shift, meaning that waveform fidelity is not a requirement.»

So it seems like your opinion is not supported by Toole’s research?

OK. The Kii I have yet to draw a conclusion on - I haven't heard it properly yet, I think. When you heard it, was it standing in free space?

But on the general point about human sensitivity to phase and so on, we don't need to go down that path: we can simply use the literal definition of 'punch'. To punch someone in the face doesn't mean to 'slap them several times rapidly with a small fish'. It means 'deliver all the energy in one moment'. All I am doing is translating the literal definition of the word into the closely-related movement of some cones. To 'punch' they have to deliver all the energy to the intended target in one moment.

 

[flipflop]

Without a definition, it's nothing but a marketing buzzword.
Based on the Interactive Frequency Chart™, I would define it as following:
"Sufficient or excess sound pressure from 100 to 170 Hz"
Going through your list of questions, the answers should be obvious with this definition in mind.

 

[solderdude]

(a) What does it take make sound with punch? Can we have punch in headphones

Actually Marv (the one and only) at SBAF made some interesting measurements that may shed some light on this matter. Which combined with @j_j his talk (and to be fair @Sergei his point) about the first wave of an 'impulse' being paramount for perception these measurements show a substantial difference in the amplitude of the wavefront.
One would say ... well that's a slow membrane but the Stax is anything but slow.
And when looking at the first post it seems 10kHz does rise fast so it's not the membrane speed causing this.
But John (REW) later stepped in with explanations as well.

Just tossing a coin.

Yes, some headphones have more 'punch' than others but in general these headphones have a boost at around 150 Hz region. Probably not accidental.
But while some headphones sound 'punchy' or show 'slam' others may sound 'boomy' or 'muddy' with a similar 'hump'
I made the plot below which contains some of the flowery descriptors often used.

Edit: flipflop just beat me to it.

 

[svart-hvitt]

OK. The Kii I have yet to draw a conclusion on - I haven't heard it properly yet, I think. When you heard it, was it standing in free space?

But on the general point about human sensitivity to phase and so on, we don't need to go down that path: we can simply use the literal definition of 'punch'. To punch someone in the face doesn't mean to 'slap them several times rapidly with a small fish'. It means 'deliver all the energy in one moment'. All I am doing is translating the literal definition of the word into the closely-related movement of some cones. To 'punch' they have to deliver all the energy to the intended target in one moment.

The Kii + KiiBXT setup (so two different setups in the same big room) I heard was in a pretty big room, high ceiling. The BXT transformed the Kiis into another type of reproduction machine. And are we surprised as you just tripled the size?

I think your notions are lacking. My Mac computer speaker is probably excellent on such technical specifications that you listed, but the Mac speaker doesn’t deliver punch, it isn’t snappy. I have previously said that Kii (without BXT) sounds like my computer speaker. So I guess size matters. Don’t you?

I reckon punch is a system quality? And are system qualities equal at all frequencies and across different SPLs, from 50 dB to 140 dB?

Could Kii’s decision to discard their marketing fluff about «a small big speaker» be a clue to follow in this thread? The Kii people are competent, but did they rely too much on computer assisted design when making the Kii? So when reality, real experience set in, they realized something was lacking; PUNCH! was lacking.

And could this story tell us something about punch? Is punch something which is difficult to model on a computer, and only real-life experience will tell you ultimately if your design is delivering punch or not?

 

[Cosmik]

Could Kii’s decision to discard their marketing fluff about «a small big speaker» be a clue to follow in this thread?

Are you strictly impartial on this? Might there have been a slight chance of expectation bias in your listening 'test'?

 

[Cosmik]

I think your notions are lacking. My Mac computer speaker is probably excellent on such technical specifications that you listed, but the Mac speaker doesn’t deliver punch, it isn’t snappy. I have previously said that Kii (without BXT) sounds like my computer speaker. So I guess size matters. Don’t you?

My earlier comment was about what would compromise a speaker's punch, not what was needed to create the best punch. Clearly, it also needs heft and the ability to move a sufficient amount of air for a sufficiently long time to convey the requisite sounds in the music. So big speakers are good. I like big speakers.

Without big enough speakers and time alignment etc. people may search for other explanations such as punch being a phenomenon of EQ. But really, if a speaker doesn't do what it says on the tin i.e. reproduce the signal, then all bets are off, and all that is left is to scrabble for 'artificial punch' in the form of EQ boosts and so on - which will have other side effects on the sound.

I'm not even saying anything that isn't an obvious fact: if a speaker doesn't reproduce the signal, it won't produce punch when, and only when, punch occurs in the music. And if a listener wants punch when it doesn't occur in the music, they're not really into hi-fi. Give them a graphic equaliser to play with, or some laptop plugins that compress or expand with configurable responses; they might find something they like with certain tracks.

 

[pozz]

There are measurements from Harman on the Performas (not sure) that show misaligned step response. Their position is that it's not superimportant on the perceptual side of things.

Punch is likely more to do with other speaker characteristics.

 

[pozz]

Just to add: from the room acoustics aspect, room gain doesn't detract or add to the sense of punch in my experience. What will contribute is the level of direct sound at the listening position, particularly versus early reflections.

 

[andreasmaaan]

I’ve always associated “punch” more with the production side of the process; audiophiles generally talk about “slam”

 

[svart-hvitt]

Are you strictly impartial on this? Might there have been a slight chance of expectation bias in your listening 'test'?

I find the Kiis very interesting. Like you, I like the concept. The speaker ticks off all the boxes (except vertical directivity). But does it pass the listening test?

After adding the BXT module, it does pass the listening test, as I see it. The BXT transforms the Kii into a speaker of more authority.

The Kii project is therefore interesting if you want to hear how a clever design sounds in a small package and in a bigger package. People should take their time to listen how size alters the listening experience.

What I just wrote MUST be in accordance with what the Kii people think themselves. Why would they otherwise triple the size and more than double the price?

 

[svart-hvitt]

Without a definition, it's nothing but a marketing buzzword.
Based on the Interactive Frequency Chart™, I would define it as following:
"Sufficient or excess sound pressure from 100 to 170 Hz"
Going through your list of questions, the answers should be obvious with this definition in mind.

The AES paper I referred to in the OP says that most of the punch happens in lower frequencies, and punch decreases as you go up in frequency. See figure 4 from the paper below. The speaker used in the test (Genelec 8040A) doesn’t have capabilities for producing the lowest frequencies, which may explain why those low frequencies weren’t tested for «punch».

 

[RayDunzl]

Everybody talks about punch but few take the time to define it. Is punch an audiophile term only, too vague to have a meaning? Or can we use audio science and engineering insight to fill the term with meaning?

Experiment with speakers:

If you do have "punch", and a punchy piece of music, and some control of EQ...

Remove some range in the bass, and see if the punchiness disappears.

My vote goes for 50-100Hz range.

Is a kick drum punchy? Yes, and it generally falls in the 50-100Hz range.

Is punch (not paunch, that's lower) felt in the chest?

If yes, guess what!

Subtle Clue:

My 9v Transistor Radio doesn't have much punch.

My four cheezy fifteens and the two twelves in the mains do.

 

[flipflop]

The AES paper I referred to in the OP says that most of the punch happens in lower frequencies, and punch decreases as you go up in frequency.

They were using noise bursts as playback material. No one would use terms like 'muddy', 'tinny', and 'sibilant' about noise bursts. The term 'punch' isn't appropriate either.
If they had used music recordings with typical kick drums, the 100-170 Hz range would likely have received a higher 'Mean Punch Score' than 63 Hz and below.

 

[svart-hvitt]

I’ve always associated “punch” more with the production side of the process; audiophiles generally talk about “slam”

«Slam» is so...amateur...

Big boys want PRaT!

https://www.whatsbestforum.com/thre...timing-or-pretentious-audiophile-trash.25102/



On a more serious note: I think many of the words used in audio and hifi contribute to the confusion instead of adding to clarity. However, on some occasions certain words or terms stick, and that could be becuase these words, or qualities, really matter - even if we don’t have all the tools yet to put them into one single formula. That’s why Mr. Heinz talks about «dynamics» even if he can’t define it in one sentence of greek letters. I believe most of these evasive words and terms have to do with speakers, where there is still some «art» to it and we can’t ask the computer to solve all the equations for us, yet. I am not a proponent of introducing magic and such into an audio discussion, and if I were to define «punch» on the gear side I would probably go for «headroom» and «radiation pattern» in combination with «direct sound>indirect sound» (> meaning «bigger than»).

 

[svart-hvitt]

They were using noise bursts as playback material. No one would use terms like 'muddy', 'tinny', and 'sibilant' about noise bursts. The term 'punch' isn't appropriate either.
If they had used music recordings with typical kick drums, the 100-170 Hz range would likely have received a higher 'Mean Punch Score' than 63 Hz and below.

They used signals to calibrate a model. This model was then used to measure the perception of punch in real music.

 

[flipflop]

This model was then used to measure the perception of punch in real music.

That's not what the abstract says.
I haven't read the paper, so I'll abstain from commenting on it further.

 

[gvl]

I don't care about punch unless it has alcohol in it, and even then I prefer scotch.