linuxaudio.org

On Sunday 22 July 2012 22:14:58 Al Thompson did opine:
> On 07/22/2012 06:12 PM, Chris Bannister wrote:

quoted text
> >> For good reasons most mixers have got a 80Hz EQ, so try to increase

> >> it there. However, IMO there's no big difference, if people say bass

> >> is from 50 to 300 or 60 to 250Hz. What notes are played and what are

> >> their

> >

> > AIUI, you can't hear "proper" bass unless it comes from at least a 15

> > inch speaker. So anything else is just a compromise, right?

>

> It is possible to build a properly designed cabinet that will get fairly

> good response in the low end, just at a GREATLY reduced output.  Having

> said that, trying to design a usable cabinet with less than a 15"

> speaker is kind of a waste of time and money, and will result in serious

> compromises.  If a cabinet isn't +/-3db down to at least 40HZ, it's not

> a good idea to rely on it as your main monitor.  The low E on a bass is

> around 42Hz.  The low B on a 5 string is 34Hz or something like that.

> If you mix on a system than only goes down to 50Hz, for example, there

> is nearly an octave of bass guitar that you will have no idea what is

> doing.  Same for kick drum.

At which point I have to tell a story.  In 1960, I worked for a bit at a

HiFi store at 5150 El Cajon Blvd in San Diego, CA.
At that time the newest pretender to the king of the hill was a box with a

10" driver & dual tweeters.  About a 2 feet square face and about 14"

deep, a ducted port bass reflex made by Bozak.  The store owner was an

experimenter, so he bought 2 of them, and took one of them apart.  He added

some cross bracing to help solidify the panels by coupling each with glued

in bracing to its opposing face, then since it had lots of crepe paper for

internal sound absorbsion, he added about 2x more of it.  And he'd ordered

the long throw version of that bass driver, the B10-AL to replace the more

limited throw std speaker.  The AL could be driven 3/4" in both directions.

After giving the glue a day to set, a dynaco amp was hooked up along with

the bench audio oscillator, and that puppy amazed us.  Using a decent

volume level at 100hz, the oscillator went down, clear to 10hz, without

detecting any of the bass reflexes normal peaks and valleys below 60 hz.

At 10hz, we could hear the air chuffing thru the port, but more

importantly, the room seemed to be bouncing.  Hooking up a turntable

typical of then, a Weathers cartridge in a 16" fairchild arm on a 16"

Battleship turntable, he got out the Command record of various instrument

solo's with emphasis on orchestral drums.  At the end of the kettle drum

solo, we heard and felt something we had never heard or felt before,

because in the std speaker that looked exactly like the rebuilt one, the

end of the drum solo was when the drummer took his foot off the head

tension pedal, you could hear the squeak of the linkage.  Pick the needle

up and move it back 20 seconds and switch the rebuilt speaker in.  That

kettle pair seemed to grow cajones with the switch, but the surprise was

that after the squeak of the pedal release on the big one, the player had

given the slack head another whack.  The whole room bounced.
So it can be done, if you are willing to pay the piper.  That one went on

the show floor that evening, beside the std one that sold for $245 each,

with a $500 tag on it.  He got to do it again, because the guy who gave him

$500 for that one wanted another just like it for his stereo system, for

obvious reasons.
A walk down memory lane, to a different time & place.
While I was in San Diego, one of the other things I did was help build a

couple tv cameras.  They were on the Trieste when it went into the mohole

in Feb 1960.  No one has been back since till James Cameron went down about

a year ago now.  Water isn't compressible?  Ahh, but it is when the

pressure against the hull is 18,000 psi.  So was the hull, it bent the

frames of the equipment racks.
Cheers, Gene

--

"There are four boxes to be used in defense of liberty:

 soap, ballot, jury, and ammo. Please use in that order."

-Ed Howdershelt (Author)

My web page:  is up!

QOTD:

	"I ain't broke, but I'm badly bent."

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