[sdiy] I got my cheap LM13600s...

[Ray Wilson]

Hi

In the continuing saga of the LM13600 I received my 25 today. I embraced the
bag and rejoiced.

I can only think that confusion reigns at Electronic Goldmine. The scene:
mom and pop Goldmine are surveying their stock.

Pa: "Hey ma, look at that shelf yonder about ready to bust with the weight
of all those LM13600s."
Ma: "Yeah, dagnabbit, what'll we do?"
Pa: "Well now less think on it, Arrow Electronics sells em for $4.25
apiece."
Ma: "Good Lord those fellers sure is greedy!"
Pa: "Yeah ma, lets give em away for $0.20 apiece and see what happens, it
might bring world peace or somethin'"
Ma: "Thats why I married you Pa Goldmine. You is one nice feller."

One week later...

Ma: "Well now, who in the hell was them SYNTH-DIY fellers anyway..."
Pa: "Lord-a-mighty we could a got $5.00 apiece for them LM13600s."
Ma: "One feller was ready to give me his kids for em."
Pa: "Oh well..."
Ma: "Hey Pa look at that shelf yonder about to bust under the weight of all
those Curtis Electromusic chips..."

The end.

Ray (LM13600) Wilson

----- Original Message ----- 
From: "Czech Martin" <Martin.Czech at micronas.com>
To: "Harry Bissell Jr" <harrybissell at prodigy.net>; "Peter Grenader"
<peter at buzzclick-music.com>; "john mahoney" <jmahoney at gate.net>;
<synth-diy at dropmix.xs4all.nl>
Sent: Tuesday, November 25, 2003 4:17 AM
Subject: RE: [sdiy] semi ot: loud speaker for synths


> Harry,
>
> -a sub in the corner was not intended.
>  I think this simply doesn't work. I can hear, if
>  low frequency pressure is on one ear or the other,
>  I do not believe into this "sub bas has no
>  direction" nonsense. The intensity on the ear
>  towards the speaker is always higher then on the other
>  ear, the closer you are the more pronounced.
>  Also, correlation has to be watched
>  for a single subwoofer, otherwise it might
>  cancel in the summing amp already
> -I can not see what the membrane diameter has to do
>  with the useable displacement. (This is not the maximum displ.).
>  But I can see that a large membrane (remember the 80cm
>  Fostex chassis?) has problems with stability and
>  partial resonances. Given that the coils, magnets
>  and crimping have the same quality, a 4*10
>  can work better as a 1x18, because the seperate membranes
>  are better controlled
> -a bandpass or other vented construction can make sense
>  if the LPF cutoff frequency is pretty low, say 50Hz.
>  Other frequencies must not be transmitted (electronic
>  filter). In that area you have the first resonant modes
>  of the room, so the characteristic has nothing to do
>  with the anechoic theoretical response.
>  A good bandpass design can prevent too much distortion,
>  which is a main problem for deep bass sinoids.
>  Only if it works with frequencies it can not handle
>  or is deliberately tuned too high you get this boomey
>  "annoy the neighbour" sound you mentioned.
>  Of course this does imply a 4 way system.
>
>
> m.c.
>
> > -----Original Message-----
> > From: owner-synth-diy at dropmix.xs4all.nl
> > [mailto:owner-synth-diy at dropmix.xs4all.nl]On Behalf Of Harry
> > Bissell Jr
> > Sent: Montag, 24. November 2003 21:46
> > To: Peter Grenader; john mahoney; synth-diy at dropmix.xs4all.nl
> > Subject: Re: [sdiy] semi ot: loud speaker for synths
> >
> >
> > Y'all got your flamesuits on ? :^P
> >
> > Like the movie "Godzilla"... bigger IS better.
> >
> > One good 18" can outrun almost any of the so-called
> > powered subs.
> >
> > Making a system with "bandpass" boxes in a mistake
> > IMHO... good for earthquake rumble and hip-hop
> > annoyance
> > of pedestrians and other motorists... but not for
> > HiFi.
> >
> > The 18" does not require special (active) EQ and servo
> > amps etc...  They are extrememly efficient by
> > comparison.
> >
> > OK now that I've whacked Peter (hmmm that sounds
> > different than I meant it.... ;^)
> >
> > lets discuss why the modern "small" subwoofer might be
> > better.
> >
> > 1) It fits in your studio
> > 2) You CAN spare the extra power
> > 3) you have no problem with the active crossovers
> > 4) did I mention its small ???
> >
> > These are good things, which you pay for in loss of
> > efficiency, and ultimately in overall SPL.  NOT a
> > studio
> > problem.
> >
> > I was assuming that the use (since we were talking
> > about like 4 x 12" speakers) would be for live sound
> > reinforcement... in which case the bigger box is going
> > to win every time.
> >
> > In my studio I'm using JBL4410 and I agree that there
> > is plenty of bass from a 10" driver and you don't need
> > bigger than that. But if I tried them live... Id turn
> > those 10" cones into confetti in no time. There is a
> > limit to the excursion possible in a 10" speaker.
> >
> > Given a choice... I'll take the 18" for live (and YOU
> > get to be my roadie).  For home, I don't feel the need
> > for subwoofer at all.  I like a good full range system
> > better than one sub in the corner...
> >
> > ...your mileage may vary :^P
> >
> > H^) harry
> >
> >
> >
> > --- Peter Grenader <peter at buzzclick-music.com> wrote:
> > > Czech, listen, I have Bob Diamond's email address
> > > (founder of Diamond Audio.
> > > later with M&K, now with Cervin Vega). He can tell
> > > you the optimum cabinet
> > > design if you want to do it yourself.  Contact me
> > > off list for that address.
> > >
> > > in regard to this:
> > >
> > > john mahoney wrote:
> > >
> > > > my point is that good low end does not require 18"
> > > drivers.
> > >
> > > Absolutely correct -18's are total overkill.  I
> > > think you've guys have seen
> > > that I worked at M&K for three or so years.  Now
> > > remember - they invented
> > > the dedicated powered sub (1973), so I assume they
> > > know something about how
> > > they work.
> > >
> > > They don't make anything larger than dual 12s, and
> > > the second one is in
> > > push-pull formation - meaning you don't hear it,
> > > it's mounted FACING INTO
> > > THE CABINET and is purposely out of phase with the
> > > other (this serves to
> > > push and pull the audible driver from the inside.  A
> > > more efficient method
> > > of what a port attempts to do).
> > >
> > > You should be fine with 12s, even 10s if the amp
> > > isn't one of those $26
> > > dollar Sanyo jobs that Genelec uses for their low
> > > end subs.  Those things
> > > suck.
> > >
> > >
> > >
> > > Peter
> > >
> >
> >
>