Creativesound FR125s

[npdang]

The Creativesound FR125s is an attractive, high end 4.5" driver with an extremely wide bandwidth. It also features a shielded motor, and a cast frame with windows under the spider landing for ventilation. If you look carefully you can see holes cut into the voice foil former, further improving airflow. The cone is made of untreated paper, with a copper phase plug sitting in the center.

http://diymobileaudio.com/pics/cssfr125s/css1.jpg
http://diymobileaudio.com/pics/cssfr125s/css2.jpg
http://diymobileaudio.com/pics/cssfr125s/css3.jpg

The fr125s certainly lives up to it's reputation as a wideband driver. Practically flat response from 80hz to 20khz on axis with a slight droop past 6khz. Off-axis response suffers dramatically past 6khz though.

http://diymobileaudio.com/pics/cssfr125s/fr.JPG

T/S parameters. Pretty spot on, except qts is a bit higher than spec and efficiency is a bit lower by ~2-3db.

http://diymobileaudio.com/pics/cssfr125s/impedance.JPG

The ridge at 3khz looks to be a room related, but there is some energy storage at 1.6khz.

http://diymobileaudio.com/pics/cssfr125s/waterfall.JPG

Energy storage at 800hz, quite good.

http://diymobileaudio.com/pics/cssfr125s/decay 800hz.JPG

Energy storage at 1600hz, pretty bad.

http://diymobileaudio.com/pics/cssfr125s/decay 1600hz.JPG

Energy storage at 3khz, very good.

http://diymobileaudio.com/pics/cssfr125s/decay 3000hz.JPG

Energy storage at 5khz, not too good. Looks like cone breakup around 5-6khz?

http://diymobileaudio.com/pics/cssfr125s/decay 5000hz.JPG

These distortion tests are conducted at 96dspl at 1m in free-air and Imo represents a fairly dynamic, real world max listening volume.

100hz: High distortion.
http://diymobileaudio.com/pics/cssfr125s/distortion 100hz.JPG

200hz: Better, but still high.

http://diymobileaudio.com/pics/cssfr125s/distortion 200hz.JPG

400hz: Much better. A suitable highpass point.

http://diymobileaudio.com/pics/cssfr125s/distortion 400hz.JPG

800hz: Not so good.

http://diymobileaudio.com/pics/cssfr125s/distortion 800hz.JPG

2000hz: Very clean at this point and above.

http://diymobileaudio.com/pics/cssfr125s/distortion 2000hz.JPG

This is probably one of the most perfect BL and KMS curves I've ever seen. Le is good, but still shows a somewhat wide variance over the operating range.

http://diymobileaudio.com/pics/cssfr125s/klippel1.JPG
http://diymobileaudio.com/pics/cssfr125s/klippel2.JPG

Overall, an excellent buy. The driver is well designed and built. I wouldn't exactly say however, that it provides uncompromised full range performance. Crossing below 300-400hz causes a significant increase in distortion, and anything above 5-6khz suffers from poor dispersion and energy storage. When used within this range though, it's definitely one of the best performers that I've come across... except for perhaps some rough spots at 800hz and 1600hz.

[newtitan]

wow they tested better than I thought :)

I know I liked what I heard personally, but I had mine semi sealed and they played "music" nice down to 80 hz--up high sounded good tooo

but hey nothing is perfect I guess :)

nice test :)

now how about

the peerless exclusive compared to the seas nextel 5.5" lol

[werewolf]

Great test! Seems to me like your comments capture the measured strengths and weaknesses perfectly. The biggest problem looks to be that resonance/energy storage at 1.6kHz. This impacts the energy storage/decay of course, but probably also explains the less-than-stellar distortion with an 800Hz fundamental ... where the second harmonic at 1.6kHz excites the resonance. BL curve looks spooky, it's so good. I guess it just shows how hard it really is to make a driver that measures good in all respects, especially one intended for "full range". You can have a great BL curve, decent inductance behavior and still get no better than average distortion if a resonance mode is excited.

[blackreplica]

Quite surprising it doesnt handle anything less than 400Hz very well given its a 4 incher with XBL. Wish the off axis performance on the top end could be better too. Overall it looks pretty good although i wouldnt consider this a true fullranger (but then again, what is, right?). My money is still on a 3 incher being the perfect car audio midrange :)

Bring on the rest of the speakers to be tested, mr dang! I'm craving for my next 'fix', muahaha

[Irwin AR]

I hope you'll be able to post the WR125S model as well in the near future.
It is said that it has better distortion figures than the FR model from 150 ~ 400 Hz.

Nice testing done here!

The first time i see someone personally using klippel :o in their testing.
Soon you'll be designing drivers :D

[theNoid]

Quite surprising it doesnt handle anything less than 400Hz very well given its a 4 incher with XBL.

I run mine fullrange as this is what they were designed to do and I have ZERO complaints about any audible distortion below 400Hz. I have them in small, sealed enclosures of about .15 cubes with moderate stuffing. This gives them a Q of about .7 and nice smooth roll-off below their inroom F3 of what I am guessing is about 90Hz or so. They are powered by an older Kenwood 100wpc receiver in my living room. I have had MANY people listen to them and the comments have been nothing but grande. Most folks have in fact commented on how great sounding they were in that 80-500Hz range. Anyhow, no computer here so take it as you wish, but I wouldn't worry about using them lower than 400Hz unless there is to be some large amounts of power fed to them, and then distortion isn;t the problem, but letting the smoke out might be.

My Fr125s Project (http://www.palmbayaudio.com/fr125.html)

Noidster

[blackreplica]

Hi Noid,

Sorry if you misunderstood my intentions, i wasnt bagging the speaker. I dont doubt they work well in your setup since you are enjoying them. i guess what i meant to say was that i was expecting distortion to be below 3% from 200-400Hz (i had very high hopes for it). Its probably not audible anyway (or at least hard to hear), just thought it would be better. doesnt mean by any means its not a bad driver though. Anyway nice speakers you've got there

[npdang]

It's audible with test tones, and arguably not with music. Reproducing bass however, this driver noticeably strains Imho... but for a 4" driver it's very impressive performance. The biggest problem with using it full range is probably the top end. I would use a tweeter with this one.

[demon2091tb]

Any tests done yet on the WR?

[trike]

Zaph Audio compared the WR to the Seas L12 and Dayton RS15S.
Lots of discussion on the CSS twins at DiyAudio as well.

I've been running a pair of FRs for a week now in a cardboard cabinet with no filtering. Other than relative low sensitivity, I really like this driver. I also ordered a pair of WRs this weekend from CSS.

[cotdt]

This driver looks very impressive for a fullrange. How about comparing it to the TB 4" bamboo fullrange and the Seas Nextel 5.5"?

[dBassHz]

now how about the peerless exclusive compared to the seas nextel 5.5" lol

x2 please

[jeroen_d]

Great test! Seems to me like your comments capture the measured strengths and weaknesses perfectly. The biggest problem looks to be that resonance/energy storage at 1.6kHz. This impacts the energy storage/decay of course, but probably also explains the less-than-stellar distortion with an 800Hz fundamental ... where the second harmonic at 1.6kHz excites the resonance. BL curve looks spooky, it's so good. I guess it just shows how hard it really is to make a driver that measures good in all respects, especially one intended for "full range". You can have a great BL curve, decent inductance behavior and still get no better than average distortion if a resonance mode is excited.

If the driver is tested on a baffle, it has no energy storage issues at 1600 Hz. To get an alternative view on the capabilities of this driver and other midwoofers (a lot of Peerless samples also), download http://www.lloxx.de/KLANG___TON_aktuell.klang_ton_aktuell.0.html at only 4 euros.

[npdang]

If the driver is tested on a baffle, it has no energy storage issues at 1600 Hz. To get an alternative view on the capabilities of this driver and other midwoofers (a lot of Peerless samples also), download http://www.lloxx.de/KLANG___TON_aktuell.klang_ton_aktuell.0.html at only 4 euros.
I'm curious... what is the effect? Diffraction?

[jeroen_d]

I think it is the way the driver is acoustically loaded and also the interference between front and backwave.

See below some measurements that I did on the Peerless HDS 134 (850488). The first one is a measurement like you did, the driver in free air. The second one is the driver mounted in an almost ideal sphere/tube enclosure, that I built after studying thoroughly this B&W concept. By the way I never tested the driver on a large open baffle but would expect the same results. The 3rd and 4th figures give the waterfall diagrams. You see serious energy storage issues at 1700 Hz with the driver in free air.

http://home.kabelfoon.nl/~dezaire/forum/npdang1.jpg

http://home.kabelfoon.nl/~dezaire/forum/npdang2.jpg

http://home.kabelfoon.nl/~dezaire/forum/npdang3.jpg

http://home.kabelfoon.nl/~dezaire/forum/npdang4.jpg

[npdang]

Thanks for the clarification. More measurements are always appreciated :)