Low, Middle and High

[andrew ivimey]

What would the panel consider, in terms of loudspeakers, the range of 'low', 'middle' and 'high' to be?

[petercom]

Ha, this is one of my bugbears.

You often hear people talking about frequencies in the 10 - 20KHz region as 'treble', and those in the 20Hz - 60Hz region as 'bass'.

Rubbish.

If you get the chance run a signal generator through your system with your eyes closed and stop when you think you've reached the midrange and, similarly, when you reach the treble.

Most people are surprised to find that what they consider bass reaches from 60Hz to 140Hz (there really isn't much below 60Hz on many recordings, and what there is is poorly relayed by most speakers), or maybe a bit higher.

Similarly 'treble' starts a lot lower than people think, around 1 - 2 kHz! 1kHz is a surprisingly high tone.

So this leaves us with 'midband' as, say, 140Hz - 800Hz or perhaps a little higher. Remember that middle A is 440Hz. You might want to quantify 140Hz to 300Hz as upper bass as it includes a lot of fundamentals from what we call 'bass instruments' and the human 'bass voice' too.

The attached chart might give you some clues as it shows the fundamentals and harmonics of musical instruments. There isn't much in the way of fundamentals above 3kHz!

Honestly it makes me mad when reviewers look at a speaker response graph and point out a peak at 10kHz as giving a 'bright treble'. At the very best it will emphasis the upper harmonics of cymbals but not much else. Most people won't even hear it at all! Bright treble is nearly always caused by crossover problems in the 2 - 3kHz region. In a three way speaker it is often the midrange unit that is responsible for 'bright treble'!

In a speaker, however, we glibly talk about a 'bass unit' handling the range up to 300 - 400 Hz and a 'midrange unit' handling the range up to 3kHz. This is where the problem of nomenclature arises, and where reviewers get mixed up, but we shouldn't apply these tags to tonal ranges.

I would rather we talked about 'LF units', 'MF units' and 'HF units' as being rather more descriptive of the splits in a typical loudspeaker range.

'Bass' and 'Treble' however are more suited to splits in the range of musical instruments and the human voice and we reference these when we talk about them. As we have seen these bear little resemblance to loudspeaker drive unit ranges.

And don't get me started on the horrible Americanisations of 'woofer' 'squawker' and 'tweeter'... uggh!

[Darren D]

Interesting,

I cross my London Ribbons at 2.5Khz, Listen to them on their own and you wonder why bother. Hardly any volume comes out of them at all. Switch them off and it sounds like you've cut to top half off!!

It is of course only the very top section that's now missing.

Same goes for the sub, 40Hz and below on it's own there's not much volume at all. Turn it off and it sounds like the bass has suddenly gone weak.

[petercom]

There you go! Take the ribbon out and you've lost the upper harmonics but not the fundamentals.

You've got to watch it with the sub, though. It will be contributing considerable harmonics right through the bass region and its addition to your main speakers in raising the level of bass energy throughout the room can be more than you realise.

Otherwise, agreed, it shows that 40Hz is almost subliminal and can hardly be heard except at very high listening levels.

[Darren D]

I actualy use the sub at a low volume setting.
My main speakers use 12" base drivers that are very fast and punchy in their own right, so I don't really need the sub to do much.

Mid range are 7" with a wizzer, I'm still undecided about those. But they do sound sweet so in no hurry to change them.

[steve s]

Originally Posted by Darren D

I actualy use the sub at a low volume setting.
My main speakers use 12" base drivers that are very fast and punchy in their own right, so I don't really need the sub to do much.

Mid range are 7" with a wizzer, I'm still undecided about those. But they do sound sweet so in no hurry to change them.

what drivers are you using daren?

[Darren D]

London Decca's (Originals were Kellys)
7" Wharfdale DDRS 8's, umm they're probably 8" then?
12" Fane POP50's (Original drivers in the Mordaunt Shorts)

All 8 ohms

15" Fane sub, forget which one now?

I have another mint boxed pair of Mordaunts with Londons and twin 10" drivers.
Had them about 6 mths and still not listened to them.

Also a pair of Original Mordaunts with the Kellys in, along with Quad 63s and various other speakers I seem to have collected.

Like you I really must sell something, but it's hard ya know....
I have no idea what I have altogether tucked in the back of the containers. I go in there sometimes and think Oh have I got one of those !!!!

[Ianm2]

yes it certainly reveals things once you have an eq. to play with modern 'bass' occurs around 80-160 hz, and, like peter says, 2-4 going on 5 and 6 khz can give brightness, even going down to 1khz. 6-8k being the upper end, praps that's even past it a bit. so most apart from bass is occuring 400-4khz, and that's optimistic, that's roughly tallying with the range of fundamentals, and that's what I have heard with the graphic, too.

certainly boosting from 80-160 hz really beefs the 'bass' up. not a lot happening below 50 hz to the extent people would call bass, its all around 80-160.

there are probably many ways to divide the audio band, say 20-20khz no arguing about range for this definition please, just the accepted audible band for conveneince

so perhaps 20-200 is bass, 200-2khz mid, and 2khz -20khz is top, (3 decades ie x10 freq.), I didn't read that anywhere, just made it up., and it conveniently works, but I have no doubt its probably been put forward b4 or similar, dividing it into decades.

you can subdivide these into low, mid and upper, or even into 4 or 5.

I would say tho, around less than 20 is infrasonic, 20-160 bass, 160-3k5 or 4- 6k is mid, and above that top, and then ultrasonic above 20k ( I would say 15k) if that's not contradictory to the std. definition, perhaps extra-sonic, or outer sonic( insert greek/latin word)

Its one way, actually, that's 2 ways

but yes, looking at instruments is very helpful.

this sort of stuff has been covered at length in books btw, and recording practise.

dogs woof, crows squawk, birds tweet

squawker is a great name for a mid unit.

[andrew ivimey]

Thanks Peter, you have nicely summed up (a lot) of what I was going to say! And then there are issues ...

What do we really hear?

I really do spend a lot of time worrying about this. I'm paid to, sure, but it is also my hobby and an active academic discussion too.

Human ears are generally held to hear the range 20Hz-20kHz. Of course you will find exceptions, particularly (a little) above this. But the other side of the coin is that many HiFi buffs will actually have much poorer hearing than the 20Hz-20kHz range. (This average range was 'discovered' by huge and repeated samples of US service personnel, average age was 20)

We know that children's hearing (when not glue eared up) is far more sensitive than their parents. And a serious caution must be observed when, eg playing Deep Purple at Dad's preferred SPL, this CAN damage infant's hearing. And we know that in this busy noisy world in which we live, our hearing deteriorates. If nothing else happens, the hair cells (the little microphones in the cochlea) wear out; high frequency ones first. So at fifty there is often a beginning of a loss and it gets progressively but slowly worse.

OTOH, they who must be obeyed always relate, shall we say, 'gender issues' when accompanying their hubbies to the clinic. We don't hear what they say, at strategic times so we boys are selectively deaf. And as proof, our kind of 'boys' are passionate about music and hifi, when often, at an objective level of the clinical hearing test our hearing is found to be wanting. Yet we insist on the finst of recordings and the bestest of equipment.

What do we really hear?

The dearest of wonderful partners, insists this is proof of our selective hearing and is another reason why we can't be taken seriously to choose what's on telly or decide the outcome of a major military conflagration. We're sunk.

So for music we need 80Hz bottom line (assertion: its all nasty boom box stuff below that!) and as Peter reminds us, concert pitch is 440Hz and very little musical content is left above say 2kHz and far far less, an octave above at 4kHz. Yes there are higher harmonics, I know, I know.

It is fascinating though how a) we audiophiles may 'tune' our hearing (having once had good hearing, presumably!) b) even severely hearing impaired people enjoy and play music and c) although I am still to be persuaded, supertweeters, for example, make any difference. <there are probably more points too>

[andrew ivimey]

Hasn't someone called a Lowther, a squawker?

But why then aren't we satisfied with say, a superb 300b SE amplifier?

Answers are, I know, legion. But your're all WRONG.