Hands On: Parasound ZoneMaster 650 Brings Audiophile Sound to Whole-House Market

The competitively priced multizone amplifier upholds Parasound’s reputation as a quality manufacturer of affordable, performance-minded products.


Parasound is one of the most interesting brands in consumer audio. Unlike a majority of manufacturers that specifically target markets such as custom install, high-performance audiophile, specialty audio or mass market, Parasound is an equal opportunity entertainer.

With product lines for the audiophile (Halo), specialty audio (NewClassic) and custom install (ZoneMaster and Z Custom), Parasound is in a minority of companies that offer solutions for just about any consumer application.

Adding to its line of ZoneMaster whole-house audio products, the company recently introduced its ZoneMaster Model 650, ZoneMaster Model 450 and ZoneMaster 250 products. We had a chance to check out and review the largest of these three amps, the ZoneMaster Model 650. The amplifier provides dealers with a sturdy, hybrid six-channel amplifier that incorporates six channels or three zones of stereo amplification.

Designed as an amplification solution that can drive just about any loudspeaker thrown at it, Parasound specifies the amplifier to produce 50 watts x six channels into 8 ohms, 90 watts x six channels into 4- or 2-ohm loads. The San Francisco company also says the amp is stable down to 2 ohms. In addition, installers can set it up in a bridged mode to produce 160 watts x three channels into 8 ohms, and 200 watts x three channels into 4 ohms.

Internally, the 1U-high amp utilizes a Parasound designed Class A/B input stage and a Class D power stage that combines the best attributes of both technologies to deliver the sound quality people equate with the brand, along with the thermal efficiency and reliability requirements necessary for custom installation.

Setting the amp up in our office system didn’t take any time. Connecting a pair of Monster 16/2 speaker cables to the amp’s included phoenix connectors, I connected the amp to a pair of Origin Acoustics THTR68 in-wall loudspeakers. Using both a disc player and my iPhone as sources, I quickly connected the sources and configured the amp to run in stereo.Like most amps designed for whole-house audio, the ZoneMaster 650 features a minimalist design with a front panel indicator that communicates channel information, and a rear panel that includes phoenix speaker connectors, line in connections for each zone, 12-volt trigger options, stereo/bridge selectors, level controls, bus options, level controls.

Starting with the disc player, I ran the amp for a couple of days to break the amp in. Listening to the amp during the break-in period I immediately thought the amp’s sound was right inline with the company’s NewClassic series. I remember well those original Parasound products that the NewClassic Series harkens back to, and I was impressed back then as I am now with the sound quality of the company’s amps.

Interestingly before sitting down to start my listening evaluations I suspect someone may have been poking around the amp because the ZM650’s circuit protection shut the amp down. Pulling the amp out I could see one of the speaker cables that were wired in the phoenix connector was pulled out and laying across the other wire. Grabbing a screwdriver I reconnected the wire and was off and running.

Initially I began my listening with some guitar-centric music from Guthrie Govan and Stevie Ray Vaughn before shifting gears with drummer Steve Smith’s jazz band Vital Information. What really struck me about the amp was how effortlessly it drove the Origin speakers, and the level of control it had on these speakers, particularly the speaker’s bottom end. Showing its dynamic capabilities I could really hear the level differences between the mastering of the Vital Information CD and Pink Floyd’s “The Wall,” which was more heavily compressed when listening to the albums through the Parasound/Origin combination.

In spending several listening sessions with the amp I also couldn’t detect any hint of digital “hardness” or sterile type of sounds coming from the amp even with its Class D power section. I found the amp completely natural sounding—very analog like with a nice neutral tonality and big soundstage.

Getting into some of Susan Tedeschi’s catalog I like the organic sounds of her records. She’s got a great voice and to hear classic Hammond Organs, along with a solid foundation of guitars, bass and drums provides a good basis to validate the midrange capabilities of an audio product. I thought the drums and bass line sat firmly within the mid-bass lower, midrange regions, and the layers of backing and lead vocals along with the guitars occupying the upper midrange region without sounding congested or rolled off.  

Like most things relating to audio, it is a matter of perspective, but my only real complaint with the amp is the lack of real estate on the rear panel. It is understandable why real estate is tight given the amp’s 1U size, but even with my smallish physical size I found it difficult to plug the phoenix connectors in, and to make adjustments on the level controls. One other thing—I found finding the exact amount of level (or volume/gain if you want to call it that) you’ve dialed in. Clearer markings would be helpful.

Putting those minor ergonomic criticisms aside, the ZoneMaster 650 is one of the few whole-house audio amps that brings audiophile performance to the whole-house audio category. I could easily see dealers combining these amps with an Autonomic MMS-5A server; a Sonos Connect server or some other digital media product to deliver a killer distributed audio experience to clients with high-resolution audio capabilities when used with components like the Autonomic servers.

CE Pro Verdict:


  • Competitive price point, and robust build
  • ZM650 combines the best traits of Class D and Class A/B designs
  • Smooth, natural effortless power delivery


  • Rear panel tough to read and navigate for some potential dealers
  • Some dealers may want more features 

About the Author

Robert Archer
Robert Archer:

Bob is an audio enthusiast who has written about consumer electronics for various publications within Massachusetts before joining the staff of CE Pro in 2000. Bob is THX Level I certified, and he's also taken classes from the Imaging Science Foundation (ISF) and Home Acoustics Alliance (HAA). Bob also serves as the technology editor for CE Pro's sister publication Commercial Integrator. In addition, he's studied guitar and music theory at Sarrin Music Studios in Wakefield, Mass., and he also studies Kyokushin karate at 5 Dragons in Haverhill, Mass.