Tech Help: SPICE Model for Pickup

[hoerni]

Hi all, this is my first time post, so I hope I'm not asking a question that has already been answered (I did search first).

Has anybody simulated a guitar pickup in a SPICE circuit simulator (PSpice, SuperSpice, etc)? I particular I'm wondering how you modeled the source.

Currently I'm using a voltage source with a series resistance and inductance. (Currently about 30mV with a 8k Resistor and 3H Inductor). This seems to be the common method I've found on the web, but someone suggested using a current source instead.

Thanks in Advance.


- Tim

 

[JB_From_Hell]

Re: Tech Help: SPICE Model for Pickup

Welcome

I have no clue what you're talking about, but it seems interesting, so stick around

 

[hoerni]

Re: Tech Help: SPICE Model for Pickup

Welcome

I have no clue what you're talking about, but it seems interesting, so stick around

Thanks for the warm welcome. This place does look interresting.

What I'm talking about is simulating a guitar's circuits in a computer modelling package. With the right model it should be possible to simulate the effect of the volume and tone knobs on the pickup frequency response. So far I've been able to get some nice curves, but I'm not sure if my model is the best

(If you want to see what I've done so far it's up in a Harmony Central thread)
http://acapella.harmony-central.com/forums/showthread.php?s=&threadid=860643

I'm an electrical engineer and I'm currently teaching a class on music engineering and technology. I'm hoping to have the students simulate a pickup and controls.

 

[rspst14]

Re: Tech Help: SPICE Model for Pickup

I bet Artie or Kent could help you with this, they're the resident engineers on the board. I'm an engineer too, but I don't have nearly the experience that they do, and I don't have much experience with PSpice. I'm sure one of them will chime in with their thoughts shortly.

Ryan

 

[Marcel]

Re: Tech Help: SPICE Model for Pickup

http://www.gitarrenelektronik.de/elektronik/elektronik.html
^^ take a look here! It's the simplest way! It's not that real but you can simulate how the tone controls and vol controls affect the frequence response....
you don't need a big computer programm for this.... it's easy to calc the formula if you use complex numbers but it's got a bit longer coz you have to do the inverse often....
I wrote a php script which simulate pickup and controls...... so be open to ask me

 

[Marcel]

Re: Tech Help: SPICE Model for Pickup

ah! I think you forgot the capacity of the pickup! This is very important!!!
take a look at the link above!
Yeah you always got some diagramms look like a damped harmonic oszillator! If tone control is down it looks like a low pass without resonant peak!

What class is this where you want to do this?
I'm studying physics! I wanna write a simulation which simulate how the string vibrates over the pickup to get the output some day!!

To answer you other question: I used a voltage source too! It makes more sense for me! The change of B-field makes a voltage!

 

[hoerni]

Re: Tech Help: SPICE Model for Pickup

ah! I think you forgot the capacity of the pickup! This is very important!!!
take a look at the link above!
Yeah you always got some diagramms look like a damped harmonic oszillator! If tone control is down it looks like a low pass without resonant peak!

Thanks Marcel. I found that link before too. It seems to be the best thing on the web. I thought about the capacitance too, but when I put the pickup on a LCR meter it couldn't even measure it.

Actually what I found with the current simulation is that there is a resonant peak when the tone is rolled off. It disappears as the tone control is increased and then a new peak is introduced as the tone control is cranked al the way up (only when a cable and amp is connected though)

What class is this where you want to do this?
I'm studying physics! I wanna write a simulation which simulate how the string vibrates over the pickup to get the output some day!!

To answer you other question: I used a voltage source too! It makes more sense for me! The change of B-field makes a voltage!

The class is called "Digital Music", but I used to call it Music and Engineering. It's a class for Junior level electrical engineers. We cover some of the basic stuff like how microphones and speakers work, the basics of electric instruments and then we head off for the fun stuff - amplifiers and effects. This year I'm adding .mp3s and psycho-acoutic compression (hence the title change). I'm currently updating the web-site, but I should have some more stuff posted soon (www.cooper.edu/~hoerni/prof.html)

I like your idea about a simulation of the vibrating string. A couple of years ago I had the class simulate the percentage of harmonics based on where the string was plucked. It was pretty basic though and didn't take the transients into account. That would be really cool to work on and combine with the pickup model.

I think I'm happy with the voltage source model too. I emailed a coworker who's a real Electo-Magnetic fields kinda guy (designs antennas for wireless work, and he's a guitarist). He thought the voltage source made the most sense too.

Thanks.


- Tim

 

[Marcel]

Re: Tech Help: SPICE Model for Pickup

Thanks Marcel. I found that link before too. It seems to be the best thing on the web. I thought about the capacitance too, but when I put the pickup on a LCR meter it couldn't even measure it.

I think you can't measure the capacity coz it's parallel to the coil so it's shorten by it..,
ah a LCR meter! Never knew there is something like this.... I thought multimeter
:smack: