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maldecido33
06-19-2007, 11:56 AM
I've got decent knowledge of crossovers; what the components in them do, how they work, etc. I'm looking for some good resources to design my own fairly basic active crossovers. They're for a simple 2-way bookshelf louderspeaker.

What sort of resources are out there?

thylantyr
06-19-2007, 03:54 PM
Might be cheaper to buy an active crossover.

DIY link
http://sound.westhost.com/projects-3.htm

maldecido33
06-20-2007, 09:31 AM
I'm sure it'd be cheaper, but I'm looking to actually learn the design process. I can design a 2nd-order LR, Butterworth, or Bessel crossover, but the only factor I'm taking into consideration is a given x-over point. I'd like to learn the processess associated with selecting crossover frequencies based upon various parameter's of the driver.

thylantyr
06-20-2007, 11:43 AM
I'd like to learn the processess associated with selecting crossover frequencies based upon various parameter's of the driver.

I see this as two paths.

The hard path - Electrical engineering

The easy path - Variable crossover, common sense, listening test


You can use your pencil, paper, calculator to figure out the technical aspect
of crossover design factoring in tons of variables, this takes time. People
are moving away from this methodology because there is speaker software
on the market that does this, but you have to learn the software which takes
time.

Or

You can build a loudspeaker using a flexible active crossover, apply some common
sense when you make adjustments, do some listening tests using a test box
and zero in on what settings gave you the best sound. Then you have choices.

1. Continue to use that 'development' processor in your system
2. Take those parameters and make a passive crossover equivalent.
3. Take those parameters and make a active crossover equivalent.

Note, if you built an active crossover, if you choose your components well
you could make your active crossover have variable frequency selection by
using precision ganged pots instead of fixed resistors. Another method is
to use fixed resistors to select crossover frequencies, but you can use
sockets and headers to make resistor modules to change the frequency,
you see this in car audio.

Which path do you take? Depends on your goals. If you want to dazzle people
with a crossover engineering marvel to show off, then make a technically
correct design, but there is no guarantee that it offers better SQ.

If you want to zero in on best SQ, then do the simple approach and don't
worry about if it's technically perfect. All that matter is that you liked the sound.

Or do a combination of both.

For car audio because of the environment, the tweaking method is ideal. You want
to be able to change variables.

For home audio you don't have installation limitations so you can choose any method,
but I still prefer the 'listening to the speaker' method and turning knobs to get the best sound.

The simple method, IMO is superior because it tackles the root cause, what gives me the best perceived sound.
But the simple method also assumes that you used good drivers and you executed a good loudspeaker recipe,
nothing dumb.

maldecido33
06-20-2007, 02:02 PM
I see this as two paths.

The hard path - Electrical engineering

The easy path - Variable crossover, common sense, listening test


You can use your pencil, paper, calculator to figure out the technical aspect
of crossover design factoring in tons of variables, this takes time. People
are moving away from this methodology because there is speaker software
on the market that does this, but you have to learn the software which takes
time.

Or

You can build a loudspeaker using a flexible active crossover, apply some common
sense when you make adjustments, do some listening tests using a test box
and zero in on what settings gave you the best sound. Then you have choices.

1. Continue to use that 'development' processor in your system
2. Take those parameters and make a passive crossover equivalent.
3. Take those parameters and make a active crossover equivalent.

Note, if you built an active crossover, if you choose your components well
you could make your active crossover have variable frequency selection by
using precision ganged pots instead of fixed resistors. Another method is
to use fixed resistors to select crossover frequencies, but you can use
sockets and headers to make resistor modules to change the frequency,
you see this in car audio.

Which path do you take? Depends on your goals. If you want to dazzle people
with a crossover engineering marvel to show off, then make a technically
correct design, but there is no guarantee that it offers better SQ.

If you want to zero in on best SQ, then do the simple approach and don't
worry about if it's technically perfect. All that matter is that you liked the sound.

Or do a combination of both.

For car audio because of the environment, the tweaking method is ideal. You want
to be able to change variables.

For home audio you don't have installation limitations so you can choose any method,
but I still prefer the 'listening to the speaker' method and turning knobs to get the best sound.

The simple method, IMO is superior because it tackles the root cause, what gives me the best perceived sound.
But the simple method also assumes that you used good drivers and you executed a good loudspeaker recipe,
nothing dumb.

I'm an electrical engineering major, but with only two semester's under my belt. Only taken an intro EE class, computer-science for EE, and EE Digital Design. Haven't gotten to the point where'd I'll learn this stuff in school, I just wanted to learn it on my own first. I've got some good budget drivers and a x-over that game with the partsexpress showcase for these drivers, and I'm messing around with tweaking stuff on the 2nd-order Linkwitz-Riley with Zobel Filter and L-Pad. After I get this down I'm gonna mess with 3rd and 4th order x-overs.