TB/MCM 8" shoot out

Ok.
Here goes.
We (MYSELF, BOB Reimer,Richard Chwiendacz) spent all day yesterday doing testing and listening on designs I have on the Go.As well as a project Bob is working on.
The list as follows a MT,MTM using the W4-657S and the 25-302S tweeter along with the W3-871S cubes.

And the 8" shoot out.
Results.For the 8" shoot out

The TB driver has a way stiffer compliance over the MCM.
The TB driver also does hit its XMAX under 200 watts.
The MCM driver has more travel and XMAX and is more stable in the 12" cube.The MCM does hit its XMAX limits but at a higher power handling than the TB.
Now these are both with listening to tones that do not drop[ to 17HZ at 200 watts.
These after all are only 8" subs.And the will take the power output but the lowest tones they both bottom out.
I have had the TB in a 12" cube ported and sealed.
Sealed the TB does not go low enough to look at.With the Port the TB had to have a port 2" X 30 " to get out of port noise.Now the port will work in the cube BUT it will take a lot of PVC elbows and it just fills the cube.Then well you have o volume left in the cube.Hence a bigger cabinet for the W8.
Now the TB nd a PR is very HAPPY HAPPY!!.In the same 12" cube internal size.
Hits hard and powers out around 250 watts as the data sheet reports.

But the winner is the MCM 55-2421.
Cone travel is farther.
A first look at the MCM checking travel looks as if it is limited on the inward travel of the cone outward its fine but inward the surround wrinkles on its full excursion inward.
That said it takes more power goes a little lower over the W8.
The PR brings the hitting power of this little 8" driver to life.
Testing both drivers on horn Cd's with tones down to 18HZ and with the intro to TOY STORY II.
These little 8" subs had the walls making noises in my home I have never heard of.The windows were dancing also.

The MCM 55-2421 is a drop in driver for the TB.
Both drivers have the same frame.Holes
The MCM has a raised spyder (that is what gives it more travel XMAX) and the TB has the spider on the lower rung and that limits its XMAX.
The TB uses a smaller vent over the MCM 55-2421.The vent hole has a screen on the MCM the TB does not!!
Other than the the dust cap is larger on the TB and TB put a coating over the cone material to make it more stable in the car audio application.The MCM is just the paper cone and same surround as the TB.Both are Bo PRO.HENCE TB.As TB owns BO PRO!

I will post some measurements later to day.
The MCM is the over all winner

Al


http://quicksitebuilder.cnet.com/wrnch2/rawacoustics/id6.html
:xeye: :xeye: :D :xeye:
What a day.