(Click image to enlarge)

The Eclipse SP6900 6×9 car audio speaker can be used as either a quality 6×9 coax, or as a 6×9 component woofer with separate tweeter.  This alone makes it unusual, but there is even more to the story (see below.)  First, though, here are the features and specifications for the Eclipse SP6900:

Specifications:

Fs:  45 Hz
Frequency Response: 45-40,000 Hz*
Efficiency:  *
Power handling: 90 watts RMS
Woofer voice coil DCR: 3.6 ohms.
Woofer Impedance: 4 ohms
Tweeter crossover: Modified 12 dB / octave (shaped response)

Features:

6 x 9 woofer section:
•Synthetic rubber roll
•Low mass, low distortion Kevlar-PMI cone
•Progressive spider w/ woven in leads to the woofer coil
•Magnet size / type / dia.:  24 oz. / Ceramic 5 / 4.312″.
•Mounting Depth: 3.7″ (Top-mount depth: 3.375″.  See drawings)
•1.5″ diameter, 2-Layer Cu wire voice coil*
•1.5″ TIL voice coil former*
•Speaker terminals: Dual spade, .205″ / .105″

1″ titanium hard dome tweeter:
•Treated cloth surround
•1″ AL wire voice coil
•Ferro fluid cooling
•Neodymium tweeter magnet

Crossover features:
•12 dB/oct. high pass design
•Low loss non-polar electrolytic capacitors
•Solid core, Hi-Q, low loss inductors
•5 watt wire wound resistors
•+6 dB or 0 dB sensitivity switch (jumper)
•Smoked plastic top crossover enclosure

System:
 •Grilles and Adaptors included
 •Mounting hardware included
 •Woofer bullet phase plug
 •Optional tweeter height extension
 •Tweeter relocation kit flush/surface mount kit includes:
    - extension wires
    – all necessary “relocation” hardware / bracket
 •External crossover
 •Tweeter sensitivity switch control

 Dimensions Drawing

*Note:  Eclipse’ specifications for this unit are in several instances too conservative.  They, for example claim only 88 dB sensitivity, while we measure   dB in the piston band of the woofer (usually the most conservative area to rate a speaker) in our “2 pi field” test baffle, in a large room.  (This test also precludes any low frequency gain from the cabin of the vehicle.)  Eclipse specifies a woofer section voice coil diameter of 1 1/4″, but anyone who looks at the unit carefully can easily determine that the voice coil is actually 1 1/2″ diameter, which actually matches up the the 90 watt rms power handling:  90 watts RMS would be a suspiciously high rating for a straightforward design 1 1/4″ coil non-subwoofer car speaker.  Additionally, depending on the mounting and other factors, usable in-car response may well go below 45 Hz, though for really powerful bass, we would recommend a good subwoofer, of course.

Price:  (unmodified) $80.00 / pair.  Modified:  See below.

For additional Ordering Information please click here.

Usage:

Recently we received a request from a customer who needed 6 x 9 woofers in the rear of his truck, and tweeters added up front.  After quite a search, we found no reasonably priced, good quality, separate 6 x 9 woofers.  However, what we did find was these rather intriguing Eclipse SP6900 6×9 coax speakers, which have the “detachable tweeter”, and an outboard, high quality crossover, as described above, and in the Eclipse manual.  This allows the SP6900 to double as a component 6×9 woofer and separate tweeter.

As a coax, the SP6900 is a good performer, with very efficient, punchy bass, and a crisp, extended top end that is strong out to 20 kHz and beyond, thanks to a neodymium magnet 1″ titanium dome tweeter with a treated fabric surrround.  Upper midscan be a problem for a 6×9 coax, but Eclipse has addressed this by positioning the tweeter such that the main 6×9 cone forms a gentle horn load to boost the upper mids from the tweeter.   This helps to overcome what is usually a weakness in the off axis performance of 6×9 coax speakers in the upper midrange, and also helps reduce the typical reflections and diffraction effects one sees in tweeters used in 6×9 coax speakers.  Eclipse calls this a “point source” design and it is reminiscent of some very expensive home and pro audio drivers with concentric woofer / tweeter designs.  (Note 1)

The SP6900 also works well in installations where the tweeter is mounted separately, near the woofer, and the woofer section is on axis with the listener.   Separate mounting of the tweeter, properly done, reduces or eliminates remaining tweeter diffraction issues, resulting in a smoothly rising, very clean top end.   However, it’s difficult to design a unit like this for everything, and if one must be off axis of the woofer section, while using the separate tweeters, the upper midrange drops down a little.  This is very common with 5″ and larger component woofers, and may be a blessing in situations where the auto’s acoustics tend to result in too much upper midrange from a flat response driver.  (Note 2) 

However, the customer mentioned above didn’t want/ need a “subdued” upper midrange response from the system, and, also, he wanted to place the tweeters further away from the 6×9′s than would work well with the existing crossover’s fairly highish High Pass frequency.  So…  we got to thinking:  The bass and lo-mid performance of the SP6900 is really pretty good.  Why not match up it’s woofer with an audiophile quality tweeter designed for a lower crossover frequency, and design a high quality crossover to go with it? 

That is exactly what we have done, and it worked out even better than we expected:  A good design now has an upgrade that makes it great, and we are working on a couple more ideas for the real audiophiles out there.  (Stay tuned!)  In the meantime, if you are looking for a 6×9 component woofer / tweeter system that can easily compete with anything available at up to twice the price, go to the Eclipse SP6900 6×9 component woofer / upgrade tweeter page.

Note 1:  We in fact do not particularly recommend Eclipse’ option of mounting the tweeter higher in the center “post”, when the speaker is used as a coax.  This may give a little more highs in some situations, but the midrange response is rougher.  We instead recommend using the tweeter sensitivity switch on “high”, or eq’ing in a bit more high end, or using the “detached mode.”  We would also note that mountings where the woofer is recessed back into somewhat of a cavity will tend to lead to “hollow” sound, regardless of how the tweeter is mounted.  Such mountings should be avoided with any driver.

Note 2:  Many manufacturers compensate for a lack of off axis upper midrange by designing in a peak in the woofer’s on axis upper response, but, unless carefully and subtly done, this is QUITE problematic.  For one thing, such peaks are usually accompanied by ringing and poor transient response in the region of the peak.  Plus, such a peak almost guarantees higher harmonic distortion from the woofer section, than need be.  In fact, harsh sound off the the upper end of the woofer section is often blamed on the vehicle’s acoustics, when in fact that may not be the cause at all.)  Then add in the fact that ringing and distortion problems cannot be equalized out.  One of the things we really like about the SP6900, in fact, is that the midrange / upper midrange is respectably well behaved, for an efficient driver, and is relatively free of serious ringing and exaggerated distortion problems.

Note 3:  For SP6900 replacements parts (separate tweeter, etc.) please click here.