What the hell is this Spice stuff?

I hear people talking about using circuit simulators, and I thought that being able to virtually mess around with components on a computer rather then real ones could save me some time and headaches.

So I downloaded this MacSpice thing and I can't figure out what the hell it is supposed to do? It just acts like an old Apple IIe where you have to type stuff in, etc.

How are you supposed to build a circuit out of words?

I don't get this. I was thinking more of a CAD thing where I would build a virtual power supply and I would plug in the values of the components and it would give me the voltage...

There was no read me with the thing that I could find. Do I need some sort of EE to use this thing?

Sorry for the super newbie post, but I have no idea what I just downloaded.

I'll guess there are better software than MacSpice. If you can get hold of a PC you can test LTSpice. I'm a Mac user myself but LTSpice (freeware) can be usefull. I have simulated my QRV-06 headphone amp amp first and also "tweaked" it a bit in simulation and the real world performance was pretty much as the simulation. LTSpice can also give you distortion as FFT charts.

What you need to know is how to draw a schematic and how you'll get hold of SPICE models. LTSpice has pretty many models in the software but sometimes you must use some other part. Simulation can be very usefull if you want to investigate how certain parts have influence, just change it ans see what you'll get. It's also convenient to have a fast PC. My runs at 1.8 GHz and could be faster.

AAMOF, I've started looking into LTSpice recently to supplement my traditional 'breadboard and see what explodes' design methods. Seeing waveforms and FFT/distortion plots is valuable, but...

Is there such a thing as a voltage source model that takes its signal from an audio (WAV) file, as well as output components that create same, so I can actually hear what the thing sounds like?

Thanks!

--Bob

Wow! :shock: never mind, I found WAV file input/output in the LTSpice help file!! :thumb: :thumb:

Can't wait to boot it up at home and try it!! heh heh!! :green: :guinness: :guinness: :guinness: :guinness:

--Bob

[quote author="nacho459"]

How are you supposed to build a circuit out of words?

I don't get this. I was thinking more of a CAD thing where I would build a virtual power supply and I would plug in the values of the components and it would give me the voltage...
[/quote]

awwww man forget that spice gobbledygook, only rocket scientists know how to use that stuff. For power supply designing though this does just what you need (prolly!).

http://www.duncanamps.com/psud2/index.html

He's got a lotta stuff on there about that spice jazz too if you're really set on it. :? :roll:

Kiira

Nacho, I was reluctant to get into simulators for a long time but was pleased when I finally did. It helps immensely to know a bit beforehand so you can better judge when the simulator lies.

The old sim packages require that you write down node numbers and indicate components between them by typing stuff. This is cumbersome.

More recent packages simply extract the lists from the schematic capture program. You still have to follow some protocols but it is much faster and easier IMO. Circuitmak*r is such a package. I don't know if they have a Mac compatible version.

Simulators can make one very lazy though, and also predict "perfect" behavior because the components of a given type from the library are all identical. The fancier packages give you the ability to step through different temperatures and so forth, but they won't warn you that you should.

I've seen people run to their computers to simulate a two-resistor voltage divider :evil:

nacho459


I like your views.
Spice it is a tool for lazy people to sit at their computer all day long.
It is a usefull tool but most of our audio circuits are
easy to build so just build them.
Then do something spice can never do.
LISTEN to the circuit.

[quote author="adrianh"]nacho459
...snip...
Then do something spice can never do.
LISTEN to the circuit.[/quote]

Hey, I bring in Robbie the Robot and his pal Kemar for that!

:green:

"The worm IS the spice, the spice IS the worm."





sorry, couldn't help meself there....

You can find worms from time to time in fresh basil. What I usually do is rinse the leaves in a collander. I have seen them in Parsley too, but not in curry powder. Too hot. Once in a blue moon, I find a couple under the fresh bay leaves I pick up north, but never in the horseradish.

what the hell is horseradish?

ohh

Who let you out of jaill? :green:

we got internet into prisons too