November 2007

Parasound NewClassic Model 2100 Preamplifier & 2125 Amplifier
An uncompromisingly neutral sound.
Review By Clarke Robinson
Click here to e-mail reviewer

  San Francisco-based Parasound was founded in 1981 by Richard Schram, with the mission of creating high-quality, audiophile-approved audio components without the stratospheric price tags typically found in the high-end, which is a raison d'ętre that I have a big soft spot for in my heart. Along the way, Schram hired John Curl, a circuit designer of "rock star" proportions who has designed equipment for The Grateful Dead, Mark Levinson Audio Systems (back when it was actually owned by Mark Levinson), and John Curl's own exclusive line of components like the $20,000 Vendetta preamplifier.

The oxymoronic NewClassic series replaces the John Curl-designed HCA amplifiers in Parasound's line-up (Curl's newer designs were given sophisticated, brushed aluminum chassis and the "Halo" moniker). Curl was not involved in the design of the NewClassic amplifiers, which are built around cool-running class AB topology (as opposed to class A/AB in the HCA and Halo gear). Schram, who still presides over Parasound, wanted something that would offer unimpeachable sound while pricing out at a level that would appeal to beer-budgeted audiophiles and the "home install" crowd. This is right up my alley, and with the new Model 2100 preamplifier hot off the assembly line, Parasound eagerly sent off a set for review.

Features, Features, Features

There are several amplifier and preamplifier options on the market in the same price bracket as the NewClassic gear (from Adcom, Rotel, NAD, and even Parasound with the Halo P3/A23 combo at just $350 more) but the amount of features and connection options it offers make it truly unique. I'm not going to catalog them all here (you can read Parasound's website for that), but I will mention the ones that were of interest to me.

Remote Control
Seems kind of odd to have to point this out as a feature, but there are preamplifiers and integrated amplifiers in the NewClassic's price range (and higher) that are not so equipped. Call me a couch potato, but the ability to adjust the volume for the listening position is essential.

Tone Controls
I like tone controls while i also understand the allure of a pure signal path, but to me the ability to take the edge off an excessively bright recording like Van Halen I (without having to swap interconnects or some other nonsense) is worth its weight in gold. The manual states that "the clearest sound will be heard with the tone controls in bypass mode", and that's where I left them most of the time. However, I was unable to hear (or measure) any sonic degradation with them engaged.

MP3 Player Input
Front panel input jacks are getting pretty common on receivers and integrated amplifiers these days. Parasound has beefed up the Model 2100 front panel input with 12dB of gain to compensate for the anemic output of most portable source components. It works well: my iPod with a line-out dock into the MP3 input played at levels comparable to my Perpetual Technologies P-3A DAC.

Phono Input
Input #1 on the Model 2100 preamplifier is switchable between line, moving magnet, or moving coil cartridges. I'm about the last person you should trust to evaluate a phono stage as I spin vinyl about four times a year (three of those are during the holidays, when I put on old Elvis and Bing Crosby Christmas albums for my in-laws), the quality of my turntable commensurate with that amount of usage. I hooked it up, and it worked.

Bass Management
The subwoofer outputs (there are two, but not stereo) on the Model 2100 preamplifier are equipped with a low-pass filter, variable between 20Hz and 140Hz. Nice, however the high-pass filter (for the mains, available through an alternate set of RCA jacks) is fixed at 80Hz. I'd rather see this reversed, as many speakers do better crossed lower than 80Hz, and most subs already have low-pass filters built-in. Still, it is a welcome addition, and very unique among two-channel preamplifiers.

High Pass Filter Switch
The speaker output on the Model 2125 amplifier sports a high pass filter that is switchable between flat, 20Hz, and 40Hz. This is designed to reduce the strain on the amplifier and smaller speakers by filtering out frequencies they wouldn't be able to reproduce anyway. When engaged, it provides an 18dB/octave slope that puts the signal about 2.3dB down at the assigned frequency (I only tested the 40Hz setting). It does introduce a (perhaps insignificant) bit of noise, and reduces the signal overall by about 1dB.

Setup

The NewClassic series doesn't blow you away with its cosmetic fit & finish, but it is built solidly enough to inspire confidence. The front panel is a 3/16-inch thick aluminum plate, the rest of the enclosure is folded sheet metal, a few gauges thicker than what you find in typical mass-market audio components. The Model 2100 preamplifier and Model 2125 amplifier ship with different power cords, the 2125's having noticeably more heft. The power consumption spec near the IEC socket on the rear explains why: the amplifier draws up to 550 watts, the preamplifier only 10. Some may argue that power cords make no difference, obviously Parasound's engineers feel otherwise. I don't mean to suggest there are worthwhile gains to be had by using expensive, exotic-material power cords, but if you're going to try one (at least with the 2125) make sure it's at least 16 gauge. The Model 2125 spent the review period plugged directly into a wall socket (with a "cheater" plug, my 2-channel system is on an ungrounded circuit), and the Model 2100 went into a power strip.

In setting up the 2125, I set the ground to "norm" (it can be lifted to address ground loop hum, which I did not experience), gain levels set to "THX" (their maximum), high-pass filter set to "flat", and load impedance set to "2-3 Ohms" (recommended by the manual to keep the amplifier cool, though it does reduce maximum power output). I used the Ascend Acoustics Sierra-1 for all of my listening, and gave the system 75 hours of break-in, as recommended by the manual.

The Model 2100 delivered to me was from the first batch Parasound had received from the factory in Asia, as such it had a software issue that made the volume level controllable by any button on every remote control I own. By the time I had swapped two emails with Parasound, an engineer was already working on a fix. I expect by now there are no units left with the original faulty software, but if you happen to get one, it can be updated via the RS-232 port on the rear of the unit. I received a replacement that worked like a charm.

So How Do They Sound?

While I'm not quite ready to accept the Aczelian notion that all amplifiers sound the same (provided they meet a battery of criteria the 2100/2125 easily attains: flat frequency response, high input impedance, low output impedance, are run below clipping, etc.); I do believe that the sonic differences between amplifiers described in the audio press are often exaggerated. The Parasound combo sounded exactly the way I expect a solid-state preamplifier/amplifier combo to sound: clean, transparent, airy in the highs, tight and controlled in the bass. In short: devoid of coloration or any sonic "character."

If you think of a sound system as a window into your recordings, the 2100/2125 combo is like Windex. It's clean, neutral presentation does wonders with excellent recordings: McCoy Tyner's New York Reunion, Alex Riel's D.S.B. Kino, Paquito D'Riviera's Portraits of Cuba and others of their ilk all sounded lifelike and involving. Of course, this uneditorializing accuracy does no favors for problematic recordings. The sibilance on Emmylou Harris' Spyboy got in the way of the music to a greater extent than it does with more forgiving gear. At the other end of the spectrum, Orlando ‘Cachaito' Lopez' debut effort, Cachaito, is one of the more "caramelized" recordings in my collection, and that's exactly how it came across on the Parasound system.

Roger Waters' Amused to Death is an excellent showcase for a system's soundstage presentation and reproduction of dynamic transients. Waters' characteristically cynical rant about war, faith, and the pervasive role of media in western society was a good recording by 1992 standards, but compared to many of today's dynamically squashed, hot mastered pop recordings it's a masterpiece. The Parasound stack whispered Q-Sound effects from every distant corner of the soundstage, while still bringing intensity and drama to the album's Jeff Beck-fueled arena rock anthems.

Amused to Death is not the most dynamically demanding album I own, that would be the Redwood Symphony's 1993 performance of Stravinsky's Rite of Spring. This is one of those audiophile recordings that bears a warning label: "CAUTION: Extremely wide dynamic range. To prevent damage to loudspeakers, please play, initially, at low volume levels." Indeed, playing it loud enough to hear the opening bassoon solo clearly makes for quite a shock when the bass drum and tympani slam to life during the violent "Ritual of Abduction". The Parasound gear handled this section (and others like it) with clarity and eye-blinking impact.

The Ascend Acoustics Sierra-1 monitors are very easy to drive, and so don't make for a very rigorous test of an amplifier. To rectify this, I brought the 2125 amplifier over to a friend's house to try it out with his Verity Audio Parsifal Encores. Turns out the Parsifals don't present a very difficult load either (the 2125 drove them just fine) and what turned out to be more interesting was comparing the 2125 to his main amplifier, the hulking Pass Labs X350.5. Putting the $700 Parasound unit against this 350-watt, $10,500 monster is hardly a fair comparison, but the fact that the 2125 wasn't completely embarrassed in this situation says something. The X350.5 sounded tighter and more controlled all around, most noticeably in the bass, and to a lesser degree in the imaging. Even more subtly the Pass unit demonstrated better tonal accuracy, portraying more of the tonewood in violins and metallic luster in horns. Still, the Parasound unit delivered vastly better than 1/15 the performance at 1/15 the price, and I imagine the 2125's bigger brother (the 250 watt Model 2250) would make an even better showing.

Unsatisfied with the brutality of the load presented by the Parsifals, I devised another torture test for the 2125 at home: by bridging the amplifier to mono and hooking up one speaker to each of the outputs (that is, one on ‘A' and one on ‘B'), the Sierra-1 effectively became a 2 ohm load, which is a traumatic task for many amplifiers. I broke out a few of my favorite mono recordings: Miles Davis' Workin', Bruno Walter conducting Mozart's 39^th, 40^th, and 41^st symphonies, and a Furtwangler 9^th (Lucern, 1953), set the volume knob to about 10 o'clock and let ‘er rip for a few hours (having the volume knob at 1/3 is nothing compared to the "1/3 power" test tones required by the FTC, but SPLs were beyond comfortable at my usual listening position). I was hoping to blow a fuse, or at least send the amp into thermal protection mode, but all that happened was an enjoyable afternoon of loud, clear music (as clear as can be expected from some of those old radio recordings) that sounded more three-dimensional than I expected from mono. The otherwise cool-running amp got a little warm over the heat sinks, but nothing that could even reheat an egg, let alone cook one (unlike some pure Class A amps).

On the Test Bench

I brought the Parasound pair to a DIY amp-builder friend of mine to take some measurements and get his impressions of the overall build. Measurements were taken using RMAA on a laptop with an M-Audio Audiophile Firewire sound card. An 8-Ohm dummy load power resistor was connected to the output of each channel for all the power amp tests.

Model 2100 Preamplifier
Popping the top of the Model 2100 reveals a clean, almost minimalist layout: separate boards for the amplification and control sections, with an off-the-shelf switching power supply in between. Amplification is provided by ubiquitous (if inexpensive) NE5532 opamps, a part so common that it's likely the music on every CD you own has already passed through a few of them in various microphone preamps, mixing consoles, etc.

This graph shows the 2100's tone controls in effect, providing a good amount of control at roughly +/-18dB at 20Hz, and +/-12dB at 20kHz. The waviness in the blue trace is a measurement artifact from the bass being turned up, and is not indicative of the 2100's performance. Distortion on the 2100 is so low that it could not be measured reliably with the equipment we had.

Model 2125 Amplifier
A massive toroidal transformer sits under the hood of the Model 2125, a part that, if you were going to try and DIY this sucker, would probably set you back around one third the retail price of the entire unit. My friend was impressed by the clean, symmetrical layout of the all-discrete circuit. He found a few cheap capacitors that were far from "audiophile grade", but giving Parasound's engineers the benefit of the doubt, we'll assume they're not in the signal path (we didn't have a schematic on hand).

While the transformer noise component at 120Hz looms large over the noise floor in our graph, at -88dB (.004%) it's unlikely to bother anybody. Distortion relating to the 1kHz signal tone is very low: we see the typical spikes in the 2nd and 3rd orders, but nastier sounding high- odd-ordered harmonics barely stick their heads above the noise floor.

Measuring the 2125's power output on the oscilloscope was encouraging…this is a 1kHz test tone playing through both channels. When the amplifier goes into clipping the tips of the sine wave curves start to flatten…the smooth curves here indicate the amp is nowhere near clipping, even though cranking out 100 volts (156 watts into 8 Ohms). While this isn't the most accurate way to illustrate power output (a distortion vs. power output curve is better), it is obvious that the 2125 easily outperforms its rated output of 125 watts.

Conclusion

I haven't heard many of the NewClassic series' competitor's products, but I suspect there are others that could deliver similarly clean, punchy, solid-state sound for around the same money. I don't know of any, however, that do it with the same breadth of features (especially in the Model 2100 preamplifier), and that fact alone should put this system in a wide range of homes. Technically speaking, the 2100/2125 combo is a solid performer. I'm sure it's possible to build a quieter preamplifier/amplifier (Parasound also makes the $11,000 JC2/JC1/JC1), but I'm not sure the improvement would be audible. Integrated amplifiers exist with similar or even better measured performance (from the likes of Krell, Bryston, etc.), of course for 3 to 4x the price.

The NewClassics make a fine upgrade for those wanting to ditch their mass-market receivers and step in to the world of hi-fi separates. Of note is that my Denon receiver sounds a bit dull in comparison. The only word of caution I offer has to do with system matching. The Parasound "sound" is uncompromisingly neutral, so combining it with speakers that are similarly revealing could result in a system that is more a tool than a toy. Some audiophiles will shudder at the mere suggestion that there could be anything "wrong" with that, as the goal for many is to recreate as accurately as possible exactly what the sound engineer intended in their recordings. It is certainly a valid goal, but perhaps not the only one. Some people just want to enjoy their albums, and find that a little honey in their tone can help. The 2100/2125 combo could still work (and work well) for those in that camp, you'll just have to get your coloration from a different link in the chain.

There's something about amplifiers that appeals to the same testosterone-producing parts of our brain that is triggered by 12-cylinder automobiles, 6.5-horsepower lawn mowers, and the like. In the end, however, each of these things has a job to do that it must do long after the initial purchase "rush" wears off. After having the 2100/2125 in my system for a few months, I don't find the two black boxes in my audio rack particularly exciting. On the other hand, I am very easily excited by the music they produce. For that they get my recommendation.

Specifications

Model 2100 Preamplifier
Frequency Response: 10Hz to 100kHz (+/-3dB) 
THD Distortion: < 0.008% at 20Hz 
S/N Ratio: 105dB, input shorted
Crosstalk: 75 dB at 20 kHz 
Input Impedance: 30k Ohms 
Output Impedance: 60 Ohms
Input Sensitivity: 250 mV for 1 V output 
Total Gain: 12dB 
Maximum Output: 6.5 V 
Dimensions: 17.25 x 14.5 x 4.25 (WxDxH in inches)
Weight: 13 lbs.
Price: $600

Model 2125 Amplifier
Power Output: 125 watts @ 8 Ohms, 200 watts @ 2 Ohms
Current Capacity: 35 amps peak per channel 
Frequency Response: 20Hz to 50kHz (+0/-3dB) 
Dynamic Headroom: 1.3dB 
Total Harmonic Distortion: 0.025% at full rated output
IM Distortion: 0.05% 
Transient IM Distortion: not measurable 
S/N Ratio: 114 dB at rated output 
Input Impedance: 33kOhms 
Input Sensitivity: 1 V in for 28.28 V out (THX standard )
Inter-Channel Crosstalk: dB, 1kHz; 73dB, 10kHz; 67dB, 20kHz 
Damping Factor: Over 150 at 20Hz
Width: 17.25 x 16 x 4.25 (WxDxH in inches)
Net Weight: 27 lbs
Price: $700

Company Information

Parasound Products, Inc.
950 Battery Street, Second Floor
San Francisco, CA 94111

Voice: (415) 397-7100
Website: www.parasound.com