Monitor 7B Repairs
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You passed.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Gardenstater wrote: »Thanks Faustin. That's interesting that Polk went from MW6500 to MW6501 without making any changes whatsoever to the crossover. Here's the thiele parameters of some of the drivers. H/T westmassguy:
Got these from various sources, including Club Polk, props to the original posters:
Driver: MW 6500 Driver's model #.
Brand: Polk Driver's brand name.
Fs: 31.0000 Hz (Free air resonance)
Vas: 2.6486 ft^3 (Compliance volume)
Qts: 0.2190 Total Q
Qms: 1.3000 Mechanical Q
Qes: 0.2640 Electrical Q
Sd: 0.0130 M^2 (Piston area)
Xmax: 3.1800 mm (Cone excursion, linear)
Revc: 6.5000 ohms (DC resistance)
Znom: 8.0000 ohms (Nominal impedance)
Pmax: 35.0000 watts maximum rated power
Driver: MW 6501 Driver's model #.
Brand: Polk Driver's brand name.
Fs: 31.0000 Hz (Free air resonance)
Vas: 2.7545 ft^3 (Compliance volume)
Qts: 0.2790 Total Q
Qms: 1.4700 Mechanical Q
Qes: 0.3440 Electrical Q
Sd: 0.0130 M^2 (Piston area)
Xmax: 3.1800 mm (Cone excursion, linear)
Revc: 7.7500 ohms (DC resistance)
Znom: 8.0000 ohms (Nominal impedance)
Pmax: 35.0000 watts maximum rated power
Driver: MW 6502 Driver's model #.
Brand: Polk Driver's brand name.
Fs: 44.0000 Hz (Free air resonance)
Vas: 1.2360 ft^3 (Compliance volume)
Qts: 0.2790 Total Q
Qms: 1.9700 Mechanical Q
Qes: 0.3250 Electrical Q
Sd: 0.0130 M^2 (Piston area)
Xmax: 3.1800 mm (Cone excursion, linear)
Revc: 3.5200 ohms (DC resistance)
Znom: 4.0000 ohms (Nominal impedance)
Pmax: 35.0000 watts maximum rated power
Driver: MW 6503 Driver's model #.
Brand: Polk Driver's brand name.
Fs: 29.8600 Hz (Free air resonance)
Vas: 3.0017 ft^3 (Compliance volume)
Qts: 0.3100 Total Q
Qms: 1.7680 Mechanical Q
Qes: 0.3760 Electrical Q
Sd: 0.0130 M^2 (Piston area)
Xmax: 3.1800 mm (Cone excursion, linear)
Revc: 6.5400 ohms (DC resistance)
Znom: 8.0000 ohms (Nominal impedance)
Pmax: 35.0000 watts maximum rated power
Driver: MW 6517
BrandL Polk Audio
* Size / Type = 6.50" treater paper cone woofer
* SPL = 91 db @ 1w/1m
* Wattage = 125 Watts RMS / 250 Watts Peak
* Treated cone woofer, rubber surround
* Response = 40 Hz. to 10 kHz.
* Weight = Right a 4 pound ea.
* Magnet = UnShielded
* VC = 1" ( 25 mm)
* Ohms = 4 ohms
* f(s) - 55 Hz.
* Q(ms) - 7.261
* V(as) - 14.60 liters ( 0.516 cf. )
* n(0) - 5.02%
* M(ms) - 18.38 grams
* R(e) - 1.86 Ohms
* Q(es) - 0.048
* SPL - 92 dB @ 1W/1m
* C(ms) - 0.44 mm/N
* Z(max) - 281.50 Ohms
* Q(ts) - 0.048
* L(e) - 31.08 mH
1 Driver Type Q BL Compliance DC Resistance Fs
3 MW 6501 1.470 5.96 N 3.250 E - 3N/M 7.750 Ohms 31 Hertz
4 MW 6502 1.970 5.16 N 1.470 E - 3N/M 3.520 Ohms 44 Hertz
5 MW 6503 1.820 5.24 N 3.550 E - 3N/M 6.540 Ohms 29 Hertz
6 MW 6509 2.100 4.57 N 3.540 E - 3N/M 8.970 Ohms 30 Hertz
7 MW 6510 1.390 6.32 N 3.410 E - 3N/M 6.570 Ohms 31 Hertz
8 MW 6511 1.405 4.34 N 3.496 E - 3N/M 3.130 Ohms 29 Hertz
9 MW 6512 1.905 4.99 N 1.588 E - 3N/M 3.466 Ohms 40 Hertz
Just found this parameter thread.
After zeroing my Fluke, I got 8.5 ohms DCR on a 6509 driver Im about to repair. This is the highest DCR Ive come across and the base plate ID is the largest and best voice coil clearance to boot.Don't take experimental gene therapies from known eugenicists.
