Somewhere on teh intarwebs Jim Lesurf wrote:
In article , ~misfit~
wrote:
Somewhere on teh intarwebs Jim Lesurf wrote:
In article , ~misfit~

Ideally, you'd equip yourself and be able to do some basic
measurements.

Indeed. I'm trying to find downloads of any good freeware that I can
use.

I'll comment in more detail later if I get a chance. But you should
be able to find various freeware around. If you use Linux (or RISC
OS) you can use some of the programs on
http://www.audiomisc.co.uk/software/index.html
to do things like create test files/audio CDs and analyse the results
in various ways.

Alas, I use Windows, and 32-bit XP Pro at that! I have a really nice little
IBM X32 ThinkPad that I'm going to use for my audio / electrical stuff. I've
installed a mate's (older) copy of BassBox Pro and it comes with a programme
called X-Over [3] Pro. However so far I've only modelled a couple of speaker
boxes, I haven't touched the X-Over part. It's supposed to be quite easy to
learn but a side-effect of my meds is bad short-term memory so learning
*anything* is extraordinarily difficult! I suppose that being 50 y/o doesn't
help either.

Annoying as, at school I was a social outcast due to being put ahead two
years and *still* coming top of the class in most subjects. I find the
contrast alarming.

However I suspect the main challenge will be
carrying out suitable measurements to get the data needed to decide
what kind of crossover may be useful.

My cheap Chinese LCR meter seems to be pretty good in that regard, at least
for inductance. Well, the only reason I say that is that it's repeatable
and, in X-Overs I've pulled apart from old speakers the parts from both
speakers measure the same. This is it:
http://www.dealextreme.com/p/4070l-2...ltimeter-26768


Unfortunately you can't use the probes to measure an inductor, the ends of
the component itself have to be inserted into the sockets on the meter.
That's annoying as I have some nice speakers around and I'd love to know the
values of the components in their X-Overs. (Also I have a friend who will
let me pull the woofer from his speakers to take a peek at how well they're
made [he's curious too but wouldn't do it himself] and it would be nice to
be able to measue inductors in situ. shrug Oh well.) Caps and resistors
have the value written on them. However I'd rather not unsolder everything
to test the inductors.

FWIW I've never bothered to make or mod my own speakers. I've always
regarded it as being too much bother as it can be very hard to reach
a good result. Although I've designed or fiddled with much of the
electronics in my audio systems, I tend to leave speakers to the
professionals as I regard that as the 'hard part' of home audio. :-)

Heh! Yes, hard and expensive. I made my first set of speakers over 30 years
ago as a teenager as I couldn't afford the prices decent boxes cost. However
I didn't bother too much with X-Overs back then (similar to a lot of
manufacturers of the time), simply adding capacitors to protect mids and
tweets. Woofers ran full-range.

Then there was a period when I was earning well and some of what I didn't
save towards starting my business I allowed myself to spend on good speakers
(and other audio gear). Alas, now I've almost come full-circle (except I
can't take part-time jobs like I used to during school holidays) and am poor
but still want to have good-sounding gear.

I find that I don't have to spend a fortune on an amplifier to get something
that sounds pretty good. It's the speakers where there's the biggest
variable, and cost. I simply can't afford to buy (built-up) anything
remotely like I can appreciate so I'm having to build my own again. However
X-over technology and understanding have come a long way and also my ears
have become more discerning.

So, due to financial constraints I'm building my own speakers, mostly using
scavenged drivers (so I don't always coughevercough have the T/S
parameters for them). Sometimes I can find them on teh webs which is great
but mostly I'm flying blind, other than what I can measure.

Oh, as a side-note, although I can wield a soldering-iron with the best of
them I've never learned much about electronics. My experience has mainly
been limited to replacing components (caps on PC motherboards being the big
one) and sticking wires together. I'm currently heh! reading this:
http://electronicstheory.com/COURSES...ICS/e101-1.htm and looking for
more similar educational material. I have a couple old amps that I'd love to
be able to fix and, more than anything else being an invalid with an active
mind (albeit one that has trouble remembering) I *need* to have something to
keep my mind occupied and the less it costs the better! g

If you can suggest any sites that might help me in my quest to learn (but
basically from the start) I'd love to have the URLs. Reading forums like
DIYAudio makes me wish I could build my own amplifier.... ;-)

Cheers,
--
Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)