DIYaudio, Parts Express, Madisound, any audiophiles out there?

[StarsFly]

What goes through an Engineer's mind upon designing a loudspeaker? Surely there must be some general guidelines, no? Perhaps. Although this is most likely dependent upon the circumstances (cost, enclosure, available power, etc).

If these guidelines do exist, what are they. If you could order them, how would you go about doing it?




I need to design a loudspeaker around these circumstances:

Cost: FREE
Frequency 20hz-20khz
Enclosure: Infinite Baffle (is it baffle or baffled?)
Available Power: .5 RMS


Okay, so this is a bit unrealistic. A full range driver capable of playing the whole spectrum? I'm not sure if that exists. Why IB? This speaker will be for a demonstration, so no enclosure! The .5 wrms is from the LM386. I'll just drive it with my Ipod.


Okay! So I need a loudspeaker with great sensitivity. Wait though, I thought sensitivity was how loud a drive could play without audible distortion (vaguely speaking). When people say "I need a driver that's really sensitive," does that mean they need one that's like 90db+ or a speaker rated at like 5wrms?

I'll stop here. I have no idea how large to make the cone, what angle should it have, what material to make it out of, etc. I assume that last part is up to the individual's taste (I prefer paper!). Btw, I have no idea why cone material affects the sound. I just see sound as a vibration of a medium. Regardless of how they're pushed & pulled, atoms are atoms, right? I have no idea how many turns I need, what AWG to use, the size of the voice coil. I have no idea what magnet to use, & what type (neo or that other one). I don't know whether I need a dust cap or not. I'm not sure how large to make the pole piece (or vent if you will).

^& why stop at the geometry of the cone in relation to the desired frequency response? You don't want a 40oz magnet with a 2" cone. ...lol, a ratio of a ratio.

Maybe I should just start with whatever kind of relation I need between the voice coil & the magnet?

I'm lost!

Thanks




*It seems to me that there are a LOT of give & takes when it comes to designing loudspeakers. For instance, you don't always need a 15" cone to get 30hz. Enclosure type plays a role here. I know there are 5" drivers capable of 30hz in the correct enclosure (like transmission line).

 

[vacuum]

I would approach designing a loudspeaker by first understanding the principles of sound and how it interacts with various materials and structures. This includes understanding the physics of sound waves, the properties of different materials, and the principles of acoustics.

Next, I would consider the specific requirements and constraints of the loudspeaker I need to design. This includes the cost, frequency response, enclosure type, and available power. These factors will heavily influence the design choices and trade-offs that need to be made.

In terms of guidelines, I would prioritize the following factors, in order of importance:

1. Frequency response: This is the most critical aspect of a loudspeaker, as it determines the range of frequencies that can be reproduced accurately. It is important to balance the desired frequency response with the other design constraints.

2. Sensitivity: As mentioned in the forum post, sensitivity is a measure of how loud a loudspeaker can play without distortion. A higher sensitivity is desirable, but it may come at the cost of other factors such as frequency response or cost.

3. Driver size: The size of the driver (cone) will determine the frequency range it can reproduce and the amount of power it can handle. A larger cone may be able to reproduce lower frequencies, but it may also be more expensive and require a larger enclosure.

4. Material: The material of the cone and other components can have a significant impact on the sound produced. Paper, for example, may produce a warmer sound while metal may produce a brighter sound. The choice of material should also consider cost and durability.

5. Voice coil and magnet size: These components determine the power handling capabilities of the loudspeaker. A larger voice coil and magnet can handle more power, but they may also increase the cost and size of the loudspeaker.

6. Enclosure type: The type of enclosure used can greatly affect the sound produced by a loudspeaker. Infinite baffle enclosures, for example, may produce a more natural sound, but they also require a larger space and may not be suitable for all environments.

Ultimately, there is no one-size-fits-all approach to designing a loudspeaker. It requires a thorough understanding of the principles of sound and a careful consideration of the specific requirements and constraints. It may also involve trial and error and fine-tuning to achieve the desired sound quality.