MoFi SourcePoint 8 vs Polk Reserve R100

Last updated: August 25, 2026

Short answer: the MoFi SourcePoint 8 for better sound quality, the Polk Reserve R100 for the lower price. The MoFi SourcePoint 8 ranks #17 of 131 bookshelf speakers at $2200. The Polk Reserve R100 ranks #100 at $649, $1551 cheaper.

What the MoFi SourcePoint 8 offers: 8” twin-drive concentric driver paired with a 1.25” soft dome tweeter, in a diffraction-reducing baffle design; rated 47Hz-30kHz. Notably more neutral and true-to-source than its sibling SourcePoint 10, which the reviewer found a bit too bright in the treble by comparison - measured about 4-5dB less high-frequency output. Excellent imaging: passed multiple stereo-panning and depth tests, including smooth continuous left-to-right pans without wobble and correct front-to-back layering of vocals versus percussion. Wide horizontal dispersion of about ±60°, broader than the reviewer expected from a coaxial design, and forgiving enough in placement that about 10° of toe-out variance and moving above or below the tweeter axis both still sound good. Excellent dynamic range and compression linearity - about 26dB of headroom up to 102dB/1m equivalent, with issues only appearing below about 60Hz. 8-ohm nominal impedance made it easy to drive on everything from a budget Denon AVR to a high-end Macintosh amplifier. No significant evidence of woofer-cone modulation distortion affecting the tweeter, even at 96dB/1m. Watch for: Like other coincident designs, produces diffraction dips around 4kHz and 7kHz when pointed directly on-axis; needs about 10-15° of toe-out to smooth those out. The rear-ported cabinet (two ports) means it can’t be placed too close to a wall without the bass becoming overblown - the reviewer settled on about 2 feet of clearance. F3 of 52Hz and F10 of 43Hz mean genuine deep bass tops out in the mid-40s Hz in-room - a subwoofer is still needed for true low-end extension. Harmonic distortion crosses the reviewer’s 3% threshold at 96dB (though it’s second-order and less audibly significant), and multitone distortion becomes noticeably more audible at that same output level. Vertical response doesn’t perfectly mirror horizontal, since the cabinet is a rectangle rather than a perfect square around the driver.

What the Polk Reserve R100 offers: Compact cabinet, unusually useful bass for its size and well-controlled woofer breakup. Erin measured F3/F10 points of 68Hz/49Hz, and the X-Port vent avoids much of the chuffing and pipe resonance common to budget rear ports. The 5.25-inch Turbine Cone woofer and 1-inch Pinnacle ring-radiator tweeter produce good detail at moderate levels, while listening roughly 20° off-axis reduces part of the elevated top octave. Watch for: Erin measured only about 85dB sensitivity and the impedance reaches 3.6 ohms, so it is neither efficient nor an entirely benign AVR load. The treble runs roughly 3dB above the midrange and becomes aggressive above about 85dB SPL. A directivity discontinuity through the woofer/tweeter crossover means EQ cannot fully repair the power response, and a 400Hz impedance feature plus 500Hz-1kHz response irregularity suggests a cabinet or system resonance. Substantial low-frequency compression at higher playback levels limits clean dynamics.

Buy the MoFi SourcePoint 8 if sound quality matters more than the price. Buy the Polk Reserve R100 if the price matters more than sound quality.

If sound quality matters at all to you, skip the Polk Reserve R100. It ranks near the bottom of the 131 bookshelf speakers, so look higher up the list instead.

MoFi SourcePoint 8 vs Polk Reserve R100

Specifications Side By Side

MoFi SourcePoint 8 Polk Reserve R100
Price$2200$649/pair
Ranked#17 of 131 in Large Size Bookshelf Speakers#100 of 131 in Large Size Bookshelf Speakers
Bass Extension (-10dB)43Hz (measured, Erin’s Audio Corner)49Hz (measured, Erin’s Audio Corner)
Bass Extension (-3dB)52Hz (measured, Erin’s Audio Corner)68Hz (measured, Erin’s Audio Corner)
Dimensions18"H x 11.4"W x 13.2"D (457.2 x 289.6 x 335.3 mm)12.8"H x 6.5"W x 10.2"D
Impedance8 ohms nominal (8 ohms minimum above 80Hz, measured, Erin’s Audio Corner)3.6 ohms minimum (measured, Erin’s Audio Corner)
Sensitivity86.3dB (measured, Erin’s Audio Corner)85dB/2.83V/1m (measured, Erin’s Audio Corner)
Drivers8" woofer, 1.25-inch soft-dome tweeter1" Pinnacle ring-radiator tweeter; 5.25" Turbine Cone midwoofer
Weight28 lbs / 12.7 kg each12.2 lb each
Woofer Cabinetported, rearported, rear X-Port

More useful head-to-heads from the same speaker class:

Prices on this page were last checked August 25, 2026 at 6:19 AM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.

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The Two Speakers In Full

MoFi SourcePoint 8: $2200 Crutchfield eBay

MoFi SourcePoint 8 ranking card

Pros: 8” twin-drive concentric driver paired with a 1.25” soft dome tweeter, in a diffraction-reducing baffle design; rated 47Hz-30kHz. Notably more neutral and true-to-source than its sibling SourcePoint 10, which the reviewer found a bit too bright in the treble by comparison - measured about 4-5dB less high-frequency output. Excellent imaging: passed multiple stereo-panning and depth tests, including smooth continuous left-to-right pans without wobble and correct front-to-back layering of vocals versus percussion. Wide horizontal dispersion of about ±60°, broader than the reviewer expected from a coaxial design, and forgiving enough in placement that about 10° of toe-out variance and moving above or below the tweeter axis both still sound good. Excellent dynamic range and compression linearity - about 26dB of headroom up to 102dB/1m equivalent, with issues only appearing below about 60Hz. 8-ohm nominal impedance made it easy to drive on everything from a budget Denon AVR to a high-end Macintosh amplifier. No significant evidence of woofer-cone modulation distortion affecting the tweeter, even at 96dB/1m.

Cons: Like other coincident designs, produces diffraction dips around 4kHz and 7kHz when pointed directly on-axis; needs about 10-15° of toe-out to smooth those out. The rear-ported cabinet (two ports) means it can’t be placed too close to a wall without the bass becoming overblown - the reviewer settled on about 2 feet of clearance. F3 of 52Hz and F10 of 43Hz mean genuine deep bass tops out in the mid-40s Hz in-room - a subwoofer is still needed for true low-end extension. Harmonic distortion crosses the reviewer’s 3% threshold at 96dB (though it’s second-order and less audibly significant), and multitone distortion becomes noticeably more audible at that same output level. Vertical response doesn’t perfectly mirror horizontal, since the cabinet is a rectangle rather than a perfect square around the driver.

Bass Extension (-10dB)43Hz (measured, Erin's Audio Corner)
Bass Extension (-3dB)52Hz (measured, Erin's Audio Corner)
Dimensions18"H x 11.4"W x 13.2"D (457.2 x 289.6 x 335.3 mm)
Drivers8" woofer, 1.25-inch soft-dome tweeter
Impedance8 ohms nominal (8 ohms minimum above 80Hz, measured, Erin's Audio Corner)
Sensitivity86.3dB (measured, Erin's Audio Corner)
Weight28 lbs / 12.7 kg each
Woofer Cabinetported, rear

Polk Reserve R100: $649/pair Amazon Polk Audio eBay

Polk Reserve R100 ranking card

Pros: Compact cabinet, unusually useful bass for its size and well-controlled woofer breakup. Erin measured F3/F10 points of 68Hz/49Hz, and the X-Port vent avoids much of the chuffing and pipe resonance common to budget rear ports. The 5.25-inch Turbine Cone woofer and 1-inch Pinnacle ring-radiator tweeter produce good detail at moderate levels, while listening roughly 20° off-axis reduces part of the elevated top octave.

Cons: Erin measured only about 85dB sensitivity and the impedance reaches 3.6 ohms, so it is neither efficient nor an entirely benign AVR load. The treble runs roughly 3dB above the midrange and becomes aggressive above about 85dB SPL. A directivity discontinuity through the woofer/tweeter crossover means EQ cannot fully repair the power response, and a 400Hz impedance feature plus 500Hz-1kHz response irregularity suggests a cabinet or system resonance. Substantial low-frequency compression at higher playback levels limits clean dynamics.

Bass Extension (-10dB)49Hz (measured, Erin's Audio Corner)
Bass Extension (-3dB)68Hz (measured, Erin's Audio Corner)
Dimensions12.8"H x 6.5"W x 10.2"D
Drivers1" Pinnacle ring-radiator tweeter; 5.25" Turbine Cone midwoofer
Impedance3.6 ohms minimum (measured, Erin's Audio Corner)
Sensitivity85dB/2.83V/1m (measured, Erin's Audio Corner)
Weight12.2 lb each
Woofer Cabinetported, rear X-Port