Modernizing Pioneer CS-G303's

[Cam94z28]

Hi,
I have decided to toy with the idea of taking an old pair of my speakers, and modernizing them. I have a pair of Pioneer CS-G303 Floor Speakers with the following specs:

6 ohms
crossover points at 3.5khz, and 7khz
12" Woofer
4 3/4" Midrange
2 5/8" Tweeter

dimensions: 15″ × 26.5″ × 12″(WxHxD)
Ported

Rather than throwing these in the garbage I thought I might update all of the drivers with what's available from partsexpress or a similar site. With crossover points that high is it worth pursuing this using the existing crossovers, or am I better off starting from scratch and building my own box(keeping mind I am not a carpenter)?

Any ideas would be appreciated.

Thanks,
-David-

[Bose(o)]

You should probably design (and have someone else help you build the box, perhaps) a new enclosure as t/s parameters do change with age--magnets are weaker, surrounds lose their stiffness, etc. Anyway, are the drivers in operable condition, are their surrounds up to par and such? If not then lend them to the garbage can. However, if they are decent then, measure t/s and we'll go from there.

[Cam94z28]

All of the drivers are in good condition(Although the woofers are showing their use), I just don't like the sound of these speakers. The woofers don't produce low notes at all, and both the mid and tweet have paper cones.

I was hoping i could use the existing crossovers, and find speakers on partsexpress that would go right into these cabinets.

[sreten]

crossover points at 3.5khz(!?), and 7khz

You'll probably find the "crossover" consists of two capacitors.
And the bass unit has no baffle step compensation,
explaining the weak bass performance.

Building a 3-way is very difficult and cannot be taken lightly,
and I don't know any good cheap 12" 3 way designs.

sreten.

[Cam94z28]

sreten,
What would the part of the crossover involved in the baffle step compensation look like. I do not have them apart now, but I do recall more than just two capacitors in the crossover the last time i had one of the woofers out.

[planet10]

Are the drivers alnico? Can you post pictures?

The crossover is the least likely part you can reuse.

I'd suggest a round of modifications -- ductseal, puzzlecoat, better wire, better caps, perhaps some box bracing, streamline the front edges of the box -- before you venture out on a complete driver replacement regime.

dave

[Cam94z28]

How do I tell if they're alnico or another type? Sorry, I'm not only a newbie to the DIY scene, but Vintage speakers as well.

I do know that the magnets looked awfully small to support a 12" woofer the last time i had them out. I'll see if i can get some pics to show you.

[planet10]

Originally posted by Cam94z28
How do I tell if they're alnico or another type? Sorry, I'm not only a newbie to the DIY scene, but Vintage speakers as well.

An alnico magnet is smaller than an equivalent ceramic unit.... i've attached a pic of a typical alnico magnet (some look a bit different -- ie soupcan units).

dave

[Cam94z28]

nope, these are the standard style magnets, they look like the magnets on any modern subwoofer, only they look to only be 10oz or so.

[sreten]

Originally posted by Cam94z28
sreten,
What would the part of the crossover involved in the baffle step compensation look like. I do not have them apart now, but I do recall more than just two capacitors in the crossover the last time i had one of the woofers out.

I find the first crossover frequency of 3.5KHz highly dubious.

Its straight forward to trace a crossover :

high pass : (applicable to midrange and tweeters)
first order series capacitor,
second order + parallel inductor,
third order + another series capacitor
etc.....
low pass (applicable to bass and midrange)
first order series inductor,
second order + parrallel capacitor,
third order + another series inductor
etc.....

You may also find resistors for level matching.

BSDC is usually illustrated by a much larger series inductor with
the bass unit than you'd expect, possibly with a parrallel resistor.

sreten.