Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Who's Online (5)

Please review the site Rules, Terms of Service, and Privacy Policy at your convenience. Rules, TOS, Privacy
Get familiar with the reaction system: Introducing the Reaction System

Gradient Select Series 4" Paper Woofer 8 ohm

Not going to go into as much detail on this one as I just did with the 8", because of a couple things. Most importantly, the Qts is way higher than advertised so use as a woofer will be of limited value:

Loudspeaker parameters:

Fs  = 85.90 Hz
Re  = 6.52 ohms[dc]
Le  = 122.37 uH
L2  = 324.19 uH
R2  = 12.14 ohms
Qt  = 0.75
Qes = 1.01
Qms = 2.98
Mms = 6.21 grams
Rms = 1.126984 kg/s
Cms = 0.000553 m/N
Vas = 2.27 liters
Sd= 54.11 cm^2
Bl  = 4.663819 Tm
ETA = 0.14 %
Lp(2.83V/1m) = 84.38 dB

Added Mass Method:
Added mass = 15.00 grams
Diameter= 8.30 cm

Do your own modeling, of course, but if you are willing to tolerate a slight rise centered at 110Hz or so, a 6L vented cabinet tuned to 65 Hz yields similar extension numbers as the 8".  Also, the 4" I was unable to bottom out against the backplate, indicating a more correctly spec'd out soft part assembly. 

Impedance curve is very smooth, with no indication of the crazy "oh-shit lookit that cliff!" shown in the advertised response:


There is a mild wrinkle around 4K, but nothing too drastic. 

For reference, here is the advertised response:



They actually provide CSD waterfall, which shows heavy ringing at 4K or so. I think this might require some creative crossover work on the low pass side of things. See what I can do.

A perfect cosmetic match for the 8":


This should make for a very attractive, basic value oriented 3-way. 

http://www.mcmelectronics.com/product/55-5550 
I have a signature.
greywarden
Sign In or Register to comment.