Center channel - Best crossover for voices

[rick57]

50-70% of soundtrack content is in the center channel.

Although many soundtracks contain some music in the center, the most important function of a center channel is maximum clarity of dialog.

Male voice fundamentals average * only 130 * Hz (female 205 Hz).
To be capable of comfortably covering deeper voices, a ‘safe‘ crossover (for argument's sake, 4th order) to bass would be about 80 Hz.

This would mean a mid-bass rather than a mid, with Fs of 50 or less, and or a Zobel.

Do you agree with these facts, or the desirability of such a low crossover for a mid for the center speaker, to reproduce male voices better than a sub/bass driver?

[Nappylady]

One of the most annoying things in the world, to me, is having the guy from Radio Shack tell me that bass sounds are non-directional, and then he tries to sell me a $200 HT setup with overglorified PC speakers (YUCK!) as satellites and an 8" woofer in a decent box.

While it's true that the REALLY BASSY sounds are non-directional, what they catergorize as "bass" really isn't--listen to the bass man in Rockapella, and hear that his voice goes way below consumer HT crossover frequencies--and then try to tell me that's non-directional! I could bounce him around the room with a decent setup and you could hear where it's coming from without a hitch.

(wow, that was quite a tangent.)

For my HT setup, I'm actually aiming at having full-range speakers (down to 45hz, up to 20k) and then a subwoofer to reach everything down to 20 hz or so. I don't believe bass becomes non-directional until about 30 hz, so that's a nice compromise, since I don't want 8" woofers in all of my satellites. This is just my personal preference; I bet if you did your crossing over at 80 hz it would be just fine, and maybe even higher than that... but please, don't go above 150. That's just insane.

[Bose(o)]

Yes, bass is non-directional but, because of distortion heard from the cone, the localization made by the listener increases. There are many ways to work around this problem, one for example, is to create a down-firing sub.

In addition, to your Radiosh$t experience, I agree, I agree, and I agree. Many times I have journeyed in after work and had a demo of 'wicked' speakers for one hundred bucks. Horn sounded like horn pluse RS cr#$py sound, mid-bass was garbbled and the bass was peaky in that there was an obvious blip in the frequency response. I told the guy that sounded decent for 100 dollars and walked away...after buying my beloved Sennies ofcourse.

Rick, where did you pick-up this research? Basically what I'm doing for my centre channel is to create it such that the response where voices are concerned are not affected by a cossover as much as possible. Unfortunately my mains are already made and the Audax drivers I am using have an increase in the response around 3800-4500Hz (rough estimate from what I remember), and will need to x-over a little differnt in what I have done for the mains. I hope to timbre match as much as possibl but, could it be possible to buy Peerless drivers or some FRs from Tangband and keep the same 'voice' as my mains?

[rick57]

A month ago I searched on Google for things like:
male +voice +fundamental
and
voice +intelligibility

IIRC there was some very good material from eg
a national voice/ singing academy, one of the pro equaliser makers, and the Schiller Institute.

All said much the same thing - female voice fundamentals average 205 Hz, male * only 130 * Hz.

A lot lower than many of us think . .

[Vatos]

I've made a centerspeaker just a few month ago.

Its made of the following units:

Monacor SPH-100KEP
Monacor DT-250

At first a had a premade crossover, but that didnt suit the speakers (I found out the hard way). It just didnt ound good enough.

Then I was advices to insert a 1.order network, because off linearity off the speakers and it wold enhance the speak.


One thing I learnt is the importance off the high sounds when we speak. It is the "Tsssssss" and "hssssssss" that gives the openness off the center.

Just my experience !

[The Paulinator]

I think crossing your subwoofer higher than 100 hz is insane, let alone 150. I just finished a center channel today using two 3" Tang Band full rangers and I am very happy with it. I think the voices sound very natural, without that raspy top end that you get with diolouge through an oversensitive tweeter.

Speaking of bass directionality, that is one of my pet peeves about the Bose systems, and all those other inferior Sub/Sat set-ups. When you are watching the Lion King and all the characters voices are coming out of the center channel, and then suddenly Mufasa bellows from under some table in the corner of your room. Just a slight loss of realism there. My little dual 3" canter channel has no problem handling most of mufasas voice.... At least enough to make your brain think that the rest of it is coming from the center channel, and not the subwoofer, where it's REALLY coming from. Keep those subs crossed over nice and low, folks.

[Nappylady]

Can I get an AMEN?

Crossover -> perhaps 60 hz? Perhaps 45? I've got a set of nearfield monitors (they're almost like very high-end bookshelf speakers) and they respond down to 45hz... if I had 5 of those and a subwoofer for everything below that, think how nice that would be!

[thylantyr]

What is your SPL levels desired
out of the center channel ?

/crazy thoughts

1. 80hz - 150hz playback from
small drivers, let say 6" midrange
is not very loud. If you expect
high spl levels, I would look into
8" - 10" drivers.

2. Typcally, midrange driver capable of
good midbass performance (lets say down to 80hz) will lack in midrange
top end ... (1k - 2k)

3. Typically, midrange driver capable
of good midrange performance
(let say up to 2k - 4k) will lack in
midbass low end (80hz).

*****************************
Compromise is always a problem,
trying to fine tune the system
design.

Do you want a good sounding
midrange operating from 200hz - 2khz
cleanly *or* a midrange driver
capably of midbass operating from
80hz - 1khz ? Pick your poison.

If you use PHL "midrange" drivers,
either 6.5" or 8", you may operate
those around 200hz if using duals
(MTM center channel) and using
a 24db slope.

The gain/loss is;
I gain better performance
between 1khz - 2khz, vs. a loss in
performance from 80hz - 200hz.

If you were to use the Seas Excel's,
then you may gain better performance on the low end, but
sacrifice the top end. Some people
think 2k is where this driver breaks
up, proably 1.5khz - 2khz crossover
is needed.

I've use a single PHL 2520 crossed
at 220hz with a 18db slope, the midrange performace is incredible
and this driver is able to handle
my mono 600w amplifier. Very
strong vocals, but the catch 22 is...
You need a high output tweeter that
can operate high pass 2khz, the
2520 sensitivity is 100db 1w/1m.

Fun stuff

[planet10]

Personally, i have been very happy with my virtual centre channel...

dave

[rick57]

> What is the desired SPL levels out of the center channel ?

Don't have a number in mind. Enough for reasonable levels in a room 22 ft* 17 ft * 10 ft.
As I'm aiming for "high" spl levels, rather than driver size, I'm focussing on best intelligibility of voice.

> Do you want a good midrange operating from 200hz - 2khz cleanly *or* a midrange driver
capably of midbass operating from 80hz - 1khz ?
For intelligibility of voice, the latter is probably more important.

The best appears to be Manger, sold by Andre (alas big $, but only use one).
http://www.manger-msw.com/en/inhalt.html
This driver is 93 db efficient, can cover from 170 Hz to beyond 20 Hz.
It's not a conventional driver, and while it can handle many octaves, it's not a normal "fullrange" driver.

Perhaps should use the Seas Excel, Triangle or PHL 10 inch to "fill in" between Peerless XLS 12 and the Manger.

I was going to go virtual centre channel, but how well does it work for mutiple people and thus off center listening?