Pioneer SP-BS22-LR (Philharmonic AAM Mod) vs Definitive Technology ProMonitor 1000

Last updated: August 24, 2026

Short answer: the Pioneer SP-BS22-LR (Philharmonic AAM Mod). It ranks #51 of 74 bookshelf speakers by sound quality at $168; the Definitive Technology ProMonitor 1000 ranks #66 and costs $249, so there is not much of a tradeoff to weigh.

What the Pioneer SP-BS22-LR (Philharmonic AAM Mod) offers: This is Dennis Murphy’s “Affordable Accuracy Monitor” (AAM) mod of the discontinued, budget Pioneer SP-BS22-LR: the stock tweeter is swapped for a Peerless BC25TG15 dome and a redesigned 3rd-order crossover is built to match it to the stock 4” woofer. CEA2034 spinorama shows only small variations from a flat on-axis response with some directivity error near the crossover, a marked improvement over the unmodified Pioneer, which the reviewer notes shows much more variation from flat. Distortion at 86dB SPL/1m is reasonably controlled above 200Hz, and tweeter distortion barely rises even at 96dB SPL/1m. Watch for: Some directivity error appears near the crossover frequency. Distortion climbs in the woofer’s range (below 200Hz) at both 86dB and 96dB SPL/1m. Minimum impedance dips to about 5 ohms with a couple of resonance peaks. This is a DIY project, not a finished retail product: Murphy sold ~$168 pre-built pairs for a while but no longer does, so it now requires sourcing a used/discontinued Pioneer SP-BS22-LR pair plus building the crossover and swapping the tweeter yourself. The mod itself is public domain, but there is no current turnkey way to buy this speaker.

What the Definitive Technology ProMonitor 1000 offers: Bass distortion is well controlled per the measurements, and the slow bass rolloff means it can be pushed fairly hard for its size. Ships with a footer that keeps the small cabinet planted despite its light weight. Watch for: CEA2034 spinorama shows severely reduced bass energy between 40-120Hz, a directivity mismatch between the tweeter and woofer, and a severe resonance/interference issue around 14kHz. Distortion at 96dB SPL was so bad the reviewer limited testing to 86dB. Direct comparison to a $118/pair Pioneer SP-BS22-LR left the reviewer calling the $500/pair ProMonitor 1000 “a bad experiment that should be forgotten” and concluding “there is nothing Pro about it.”

Buy the Pioneer SP-BS22-LR (Philharmonic AAM Mod). It ranks higher for sound quality than the Definitive Technology ProMonitor 1000 and costs less, so there is no real case for the other one.

If sound quality matters at all to you, skip the Definitive Technology ProMonitor 1000. It ranks near the bottom of the 74 bookshelf speakers, so look higher up the list instead.

Pioneer SP-BS22-LR (Philharmonic AAM Mod) vs Definitive Technology ProMonitor 1000

Specifications Side By Side

Pioneer SP-BS22-LR (Philharmonic AAM Mod) Definitive Technology ProMonitor 1000
Price$168$249.00
Ranked#51 of 74 in Medium Size Bookshelf Speakers#66 of 74 in Medium Size Bookshelf Speakers
Bass Extension (-3dB)78Hz (measured, Audio Science Review)95Hz (measured, Audio Science Review)
Bass Extension (-10dB)60Hz (measured, Audio Science Review)80Hz (measured, Audio Science Review)
Drivers1x 4" curvilinear-cone woofer (stock Pioneer), 1x Peerless BC25TG15 1" silk dome tweeter (replacement)1" aluminum dome tweeter, 5.25" BDSS mid/woofer, 5.25" planar bass radiator
Weight9 lbs / 4.1 kg7.3 lbs / 3.29 kg each
Sensitivity83dB (2.83V/1m, measured by Audio Science Review)86dB (2.83V/1m, measured, Audio Science Review - reviewer noted this vs. a manufacturer spec of 91dB)
Impedance8 ohms nominal (approx. 5 ohms minimum, measured by Audio Science Review)8 ohms nominal
Crossover Frequency3000Hz-
Dimensions12.6"H x 7.1"W x 8.5"D (320.0 x 180.0 x 215.0 mm)10.88H x 6.25W x 6.5D in
Woofer Cabinetported, rearpassive radiator
Frequency Response-47Hz - 30kHz (Manufacturer specified)

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The Two Speakers In Full

Pioneer SP-BS22-LR (Philharmonic AAM Mod): $168 eBay

Pioneer SP-BS22-LR (Philharmonic AAM Mod) ranking card

Pros: This is Dennis Murphy’s “Affordable Accuracy Monitor” (AAM) mod of the discontinued, budget Pioneer SP-BS22-LR: the stock tweeter is swapped for a Peerless BC25TG15 dome and a redesigned 3rd-order crossover is built to match it to the stock 4” woofer. CEA2034 spinorama shows only small variations from a flat on-axis response with some directivity error near the crossover, a marked improvement over the unmodified Pioneer, which the reviewer notes shows much more variation from flat. Distortion at 86dB SPL/1m is reasonably controlled above 200Hz, and tweeter distortion barely rises even at 96dB SPL/1m.

Cons: Some directivity error appears near the crossover frequency. Distortion climbs in the woofer’s range (below 200Hz) at both 86dB and 96dB SPL/1m. Minimum impedance dips to about 5 ohms with a couple of resonance peaks. This is a DIY project, not a finished retail product: Murphy sold ~$168 pre-built pairs for a while but no longer does, so it now requires sourcing a used/discontinued Pioneer SP-BS22-LR pair plus building the crossover and swapping the tweeter yourself. The mod itself is public domain, but there is no current turnkey way to buy this speaker.

Bass Extension (-10dB)60Hz (measured, Audio Science Review)
Bass Extension (-3dB)78Hz (measured, Audio Science Review)
Crossover Frequency3000Hz
Dimensions12.6"H x 7.1"W x 8.5"D (320.0 x 180.0 x 215.0 mm)
Drivers1x 4" curvilinear-cone woofer (stock Pioneer), 1x Peerless BC25TG15 1" silk dome tweeter (replacement)
Impedance8 ohms nominal (approx. 5 ohms minimum, measured by Audio Science Review)
Sensitivity83dB (2.83V/1m, measured by Audio Science Review)
Weight9 lbs / 4.1 kg
Woofer Cabinetported, rear

Definitive Technology ProMonitor 1000: $249.00 Amazon eBay

Definitive Technology ProMonitor 1000 ranking card

Pros: Bass distortion is well controlled per the measurements, and the slow bass rolloff means it can be pushed fairly hard for its size. Ships with a footer that keeps the small cabinet planted despite its light weight.

Cons: CEA2034 spinorama shows severely reduced bass energy between 40-120Hz, a directivity mismatch between the tweeter and woofer, and a severe resonance/interference issue around 14kHz. Distortion at 96dB SPL was so bad the reviewer limited testing to 86dB. Direct comparison to a $118/pair Pioneer SP-BS22-LR left the reviewer calling the $500/pair ProMonitor 1000 “a bad experiment that should be forgotten” and concluding “there is nothing Pro about it.”

Bass Extension (-10dB)80Hz (measured, Audio Science Review)
Bass Extension (-3dB)95Hz (measured, Audio Science Review)
Dimensions10.88H x 6.25W x 6.5D in
Drivers1" aluminum dome tweeter, 5.25" BDSS mid/woofer, 5.25" planar bass radiator
Frequency Response47Hz - 30kHz (Manufacturer specified)
Impedance8 ohms nominal
Sensitivity86dB (2.83V/1m, measured, Audio Science Review - reviewer noted this vs. a manufacturer spec of 91dB)
Weight7.3 lbs / 3.29 kg each
Woofer Cabinetpassive radiator