Profile: Monsoon MH-505 5.1 surround sound speakers

For my first profile I will be starting with my very own set of speakers, Monsoon's multimedia flagship model, the fantastic MH-505's.


Thanks to the wonders of the Internet Archive, we are able to go back and pull some of the specs and media points on the MH-505's. Here they are:

The MH-505 is a six-piece, full surround 120 Wmax (85 W RMS) system incorporating a newly-developed high-powered bandpass subwoofer and revolutionary PFT™ Planar Focus Technology. By offering directional control, extremely fast transient response, and very low distortion, the MH-505 sets a bold new price-performance benchmark for surround sound systems.

This 5.1 Surround Sound System ensures that you'll never experience DVDs, 3D gaming, or Internet audio the same way again, as Monsoon delivers the clear highs and booming "front row center" sound of home theater, right at your computer. Comes with four high-performance flat panel satellite speakers with revolutionary PFT™ Planar Focus Technology, one center channel satellite speaker, an integrated bandpass subwoofer, one surround-sound control module, one AC adapter and connection cables. Optional high-quality metal floor stands available separately.

Just U.S. $179.99. Three ways to order:

For use with 5.1 Channel Soundcards (Backwards Compatible for users with 4 Channel Soundcards).

MH-505 System Specifications:

• Front L-R, rear L-R satellites: 3 x 5-inch dipole-radiating PFT™ high frequency transducer*; 2.5-inch cone driver, midrange, — 0.30 liter sealed
• Center channel satellite: 2.5-inch full range cone driver, 0.30 liter sealed
• Amplifier power: 120 Wmax**, 85 Wrms
• Crossover: Active, third order at 200 Hz; Passive, second order at 1500 Hz
• Subwoofer drive unit: 5.25 inch cone driver, Xmax = ± 5mm
• Subwoofer cabinet: 6.75 liter bandpass, tuned to 110 Hz; 9.50" H x 7.25" W x 10.88" D
• Controls on subwoofer: None
• Controls on surround-sound control module: Master volume, bass volume, fader control, headphone jack, mute and system status indicator
• System frequency response: 50 Hz -
  20 kHz (in workstation environment)
• Maximum SPL at 0.5 meters: 105 dB using EIA 426B noise

Amazing that so much sound could be bought for so little money. My own set was on sale for $150.00 US when I bought them. What a deal!

Of course, the key to this system was not the (admittedly underpowered) sub-woofer, but the absolutely fantastic PFT speakers that made up the right and left front and rear channels. These speakers are capable of such utterly perfect audio imagery that they rival speakers that cost as much as 10 times more. the MH-505's are truly the ultimate "audiophile" multimedia 5.1 surround sound system.

At the time of release, these speakers were given thorough reviews by most of the major online review sites of the day. Many of these reviews are still up and available today. Here are a few links:

IGN Review

Macworld review

Extreme tech review *** This is a particularly good review that even includes cross-section graphics of the Flat Panel speakers. I highly recommend this review.***

Of course, like all of the Monsoon multimedia systems, the Achilles Heel of the MH-505's is that horrific sub-woofer. Specifically, the circuit board and the utterly cheap components that it is made of. The speaker cone itself is actually quite good. However it is driven by a totally inadequate control system.

Sadly, due to the rather murky way in which Monsoon perished there is little evidence available to tell us exactly why such a poor control board was paired with such fantastic speakers. Most of the people I have spoken to simply pin it on cost control.

Essentially, to hit that fantastic price point something had to be sacrificed. Since the Flat panel speakers, being the centerpiece of the system, couldn't be cut, something else had to give. That was (apparently) the control system embedded into the sub-woofer.

The primary failure point of these control systems was the connection to the "control pot". The 9 pin DIN connectors that were used were of such inferior quality that they often developed shorts within a year or two of ownership. Alternately, problems would develop elsewhere on the board itself, causing low-frequency buzzing and humming in the sub-woofer. (My own sub-woofer suffered this fate.)

But the satellite speakers, those wonderful, wonderful PFT speakers. They are like gold. If you have a set, hold onto them!

The MH-505's appear to have been the last set of speakers designed by Sonigistics before they were bought out by Level 9 sound, and then eventually by Eastech. Once bought out, no more 5.1 systems were designed, (Although the 4.1 surround MM-2000's were released later at a much higher price point.) and the design and marketing focus shifted to the Automotive sound department.

So raise a toast to the great swan song of Monsoon Multimedia, the glorious MH-505 5.1 surround sound speaker system.