Some really good drivers from Peerless for the DCH
They are not the current stock but they are quite similar to other current Peerless drivers. Data is measured using Dayton Woofer Tester 3.
* Manufacturer:  Peerless
* Model:  850126
* Piston Diameter = 175.0 mm
* f(s)= 48.45 Hz
* R(e)= 6.00 Ohms
* Z(max)= 58.76 Ohms
* Q(ms)= 4.488
* Q(es)= 0.511
* Q(ts)= 0.459
* V(as)= 43.160 liters     (1.524 cubic feet)
* L(e)= 1.91 mH
* n(0)= 0.92 %
* SPL= 91.72 1W/1m
* M(ms)= 20.31 grams
* C(ms)= 0.53 mm/N
* BL= 8.52
*PP cone inverted dome looks like the CC line expected +/-5mm, rubber surround.

Impedance is pretty straight forward, tuning to 50 Hz.

The downward slope in the nearfield of the driver below 100 Hz indicated the low Q of the driver resonance and the good radiation resistance offered by the pipe. The dip in driver near field response (black) is centered at 50 Hz the irregularity is due to a room resonances.

This drver sound really good in the DCH, a very natrual easy balance in the music with both weight and slam in the bass when called upon.

The next one is also good but for some reason not quite as good to my ears at least.

* Manufacturer:Peerless
* Model:  831862
* Piston Diameter = 170.0 mm
* f(s)= 35.66 Hz
* R(e)= 3.19 Ohms
* Z(max)= 22.41 Ohms
* Q(ms)= 2.101
* Q(es)= 0.349
* Q(ts)= 0.299
* V(as)= 60.770 liters     (2.146 cubic feet)
* L(e)= 0.70 mH
* n(0)= 0.75 %
* SPL= 90.87 1W/1m
* M(ms)= 23.72 grams
* C(ms)= 0.84 mm/N
* BL= 6.97
Noninverted fabric dome and foam surround on this one.

The frequency response is exellent very flat up to 2 kHz, it also sound good, but not as good as the other one, why that is and if it will change with some decent amount of damping material in the pipe I do not know, presently.