Crown K2 Amplifier and Studio Reference 1 Amplifier


A Pair of Crowns

Les Turoczi

13 March 2002


K2 Stereo Amplifier
500 Wpc @ 8 ohms
800 Wpc @ 4 ohms
1,250 Wpc @ 2 ohms; in all cases with both channels driven to 0.1% or less THD
Damping factor: >3000 from 10 to 400 Hz
Signal to Noise: greater than 110 dB below full rated bandwidth power
Price: $1878 USD

Studio Reference 1 Stereo Amplifier
780 Wpc @ 8 ohms; both channels driven to 0.1% or less THD
1,160 Wpc @ 4 ohms; both channels driven to 0.1% or less THD
Damping factor: >20,000 from 10 Hz to 200 Hz
Signal to Noise: greater than 120 dB below full rated bandwidth power
Price: $4532 USD

Crown Audio Inc.
P.O. Box 1000
Elkhart, IN 46515-1000
Phone: 1-219-294-8200; 1-800-342-6939
Fax: 1-219-294-8301


For those of us who have been around audio for decades, the name Crown is both familiar and confounding. In explaining this statement, the familiar part needs little clarification, however the confoundingpart does. It really stems from the fact that while this company has been associated with quality construction concepts, strong ideas and brute force power amps, its direct association with the world of “pro audio” has kept it, in some consumer-audio circles, at arms length, especially from many in the “serious audiophile” community.

Actually, this company was initially founded as a means of offering support for its own religious community, which had a strong commitment to sending missionaries to underdeveloped parts of the globe. As I recall it, their early products from the 1950s were open reel tape recorders, which had to be built to incredible standards for durability under varying and adverse conditions, while delivering outstanding audio performance. Those machines were intended for recording speech at very slow tape speeds so as to allow for tape economy as well as communicating back and forth with the states on missionary news. The sonic performance, at speeds more typically used for recording music, was actually quite startling for its time, and audio aficionados started discovering these impressive tape recorders and incorporating them into their home music systems.

Eventually Crown International was created and they applied their engineering expertise to a wide range of audio products, most especially power amplifiers. In the 1960s the famous DC300 amplifier began to gain much attention in sound reinforcement applications for music concerts in many types of venues. I can still recall the good old days of hearing outstanding rock and roll performances at the famous Fillmore East in New York City, where racks of big Crown amps were coupled to gigantic JBL speakers. In fact, as part of my misspent youth in the late 60s and early 70s, I managed to run my own pair of JBL S7R speakers with a Crown DC300A amp and IC150 preamp, plus a Technics SP10 turntable with an SME arm/Shure V15 cartridge, Dyna FM tuner and Tandberg 64 tape recorder. In some ways, mostly nostalgic, I still miss that system, although my hearing has been spared as a result of eventually finding a more conservative listening level in successive systems.

These days the company, now newly renamed as Crown Audio, is a division of Harmon International. It continues with many types of professional audio products including the two amplifiers that are the point of this review. My home sound system speakers utilize a pair of Nestorovic satellites along with their matching subwoofers. While Nestorovic 150-watt tube monoblock amps power the satellites, a pair of Electron Kinetic Eagle 400 solid-state monoblock amps feed the subs. As various parts of my overall system have changed and generally improved over time, I found that the bass performance, while adequate, was not keeping up with the rest of the goodies. That put me on a two year quest to find alternate amplifiers for the subwoofers, and this eventually lead me to the Crown K2 amp, which is the first topic of this report. Since Crown had just recently updated their even beefier Studio Reference amp, that behemoth was kindly sent along with the K2 amp for all-purpose use and it will also receive some general commentary as we move along.

I won’t spend much time here trying to explain the dichotomy that exists between the worlds of pro audio and the high-end audiophile. Rather, let me be terse by noting that some fairly different goals and objectives apply regarding how these two arenas look at sound, sound production and sound reproduction. The engineering and physics that relate to the demands of the pro world often cause those folks to find it hard to comprehend the issues and/or subtleties that audiophiles obsess over. This could become an essay unto itself, but let me be crass and suggest that I’ll let others chew on those topics at another time and place.


Not at all surprisingly, the Crown amps are very well constructed. They certainly are meant to be bulletproof and sturdy, which is something that can’t always be said about typical audio components. They have features and constraints that may be important only to studio and location sound engineers. Particular attention has been paid to protection circuits and to control features, which are unconventional for home use, however, the objective specs are enviable and there is emphasis on delivering high quality sound over many years of service. In my opinion, the cost-effectiveness, the fine sonic performance and the engineering prowess that these products represent should make them attractive to music lovers and audiophiles to a larger degree than generally appears to be the case. Let’s see if that makes sense.

Big, clean power has to be among the first characteristics to talk about for both of these Crown amps. The K2 amp, in particular, was high on my short list of potential candidates to drive my subwoofers, first because of its strong output ratings and a very high damping factor which was given as >3,000 from 10 to 400 Hz. It is small, in fact surprisingly small, being able to fit into a 19-inch wide rack (the standard in the pro world), with a height of 3.5 inches and depth of 16 inches. You could easily stack up 10 of these babies and still be only around a yard tall! One nice feature is the lack of a cooling fan that amps of this wattage often have, so quiet operation is no problem. The K2 weighs 38 pounds. There are 5-way speaker binding posts and XLR balanced inputs. However, reflecting the pro-world design, there are no RCA jacks. You could employ balanced 1/4″ phone jacks for inputs if you are unable to use XLRs, but that is not very common amongst our ilk. (When last did you see “amongst” and “ilk” in the same sentence?) There are many other features and details such as sensitivity adjustments, useful gain controls, exotic protection circuits, which may be less immediately relevant, but you can pick up on them via the very informative Crown website as needed.

Within this review are listed many of the recordings used in my evaluation process. A variety of genres are covered and represent the core of repertoire selected for systematic critical listening purposes. Naturally, an even wider range of material comprises my general listening habit, and a good part of that does include LPs. The gist of this is that I do listen to lots of different types, styles and forms of music in hopes of enjoying it first for pleasure/esthetics, and then secondly, for critical appraisal as needed for formal reviewing. One additional twist involves the original recordings, which I started creating in 1999. My good fortune includes living in an area where there are plenty of serious music concerts. Many of these musicians and performing groups have been happy to let me tape their live performances, which are in good venues and always unamplified. With a decent DAT rig, employing fancy microphones and other paraphernalia, I have been able to capture a wide range of music in a two-channel “purist” fashion, often sitting close to my mic stands, but always in the audience. The ability to rehear such music at home on the big rig, shortly after the actual performance, while occasionally humbling, has done much to help me appreciate the pleasure that excellent recordings can bring. Quite frankly, many of my audio friends think highly of these concerts, once transferred to CD as well, and the performers are outright thrilled to have this documentation in a very decent sonic presentation. I have no pretensions about being a Jerry Bruck or Peter McGrath, let alone Keith Johnson, but this fun stuff has been both enjoyable and dramatically educational in terms of developing my ear and sonic perceptivity. As a last point here, let me say that I am not alone in finding these recordings to be frequently better than most commercial discs. Typically those recordings have gone through incredible processing steps between mic feed and final pressing. Sometimes simpler can be better!

As to actual amplifier performance, I can unequivocally say that bass performance at chez Turoczi via the Crown K2 has never been better. It is tight and controlled, but fully tuneful even though we are only talking about the bottom 2+ octaves of music. Anyone who has had the experience of listening to music via high quality bass reproducers knows that such music often conveys a magical sense of the venue in pleasant and desirable ways. Namely, the feel of the room boundaries, the underpinnings of bass-generating instruments when present, as well as incidental sounds like furnace/HVAC noises or outside traffic, all add strangely to the sense of “being there.” This now happens in gangbuster ways with the K2 in place. There appears to be no sense of power limitation while the bass extension and accuracy really shine, particularly on one of my favorites, pipe organ music, as well as with synthesizer stuff or other big bass sounds. If you like that sort of deep stuff, don’t miss the engineering prowess of Keith Johnson on the Minnesota Orchestra’s Copland 100 disc [Reference Recordings RR-93CD]. Better yet is their Minnesota Orchestra Rachmaninoff [Reference Recordings RR-96CD] release, where everything appears to be recorded even more naturally. Many of my own original recordings have really shown me what ambience retrieval and intrusive, extraneous noises are all about. Perhaps in another report I’ll convey some more of the fun, frustrations and sonic education that comes from that activity…it certainly has helped me to think more clearly about deep bass and room effects, etc.

For a few other examples of music that allows the bottom end shine, check out things like the Yuri Honing disc Star Tracks [Jazz in Motion 9920102] especially on the “Walking on the Moon” track. Or, listen to the Dire Straits track using “Private Investigations” from On the Night[Warner Brothers 45259] to see what big synthesizer bass can do. The Cowboy Junkies CD, The Trinity Sessions [RCA 8568-2-R] is famous for the intriguing deep bass material that actually was generated by the ventilating system chugging away in the church venue…it actually adds some mystery to a few of the tracks. I’ve run into extraneous sonic intrusions like this several times on my own recordings, or certain noisy actions of inconsiderate audience members, but I don’t always appreciate them. And don’t ignore the big bass drum in The Mikado from Telarc with Charles Mackerras directing the Welsh National Opera [Telarc CD80284]. All of these recordings will give both your woofers and your complete system a workout.

If you have need for a bass amplifier, I most heartily recommend the Crown K2 as a serious contender. Yes, I did try a few other units from very well known amp makers, and while all of those pieces had their own signature, the K2 came across with the most musical performance, particularly regarding agility in bass reproduction. The bad news is that, as a full range amplifier, I would look elsewhere. While the sound was good, it was not distinguished or especially musically refined. It had that analytical, sterile and detached sense. Keep in mind that in my heart I am a tube guy, as can be seen from my equipment list entries. I have had many solid state pieces of equipment over the years and just prefer what tubes do in a carefully matched system and room. You might like the sound of the K2 full range, but I would recommend a trial listening before plunking down your dollars. Ultimately, I regarded the K2 highly enough for my subwoofer application that I bought it. Even a fancy, well-reviewed competitive amp that cost 3.5 times more couldn’t do better than the K2 on my subs.

The Crown Studio Reference 1

Let me now turn to the Crown Studio Reference 1 amp. This is a truly impressive looking piece of electronics. It is “Industrial” in the best sense of the word, and has even more special features than the K2. First of all, it won’t plug into your wall outlet. A captive 10 AWG power cord with a special NEMA TT30P plug termination is standard because of electrical demands and safety concerns. So, you can change your AC wall outlet, substituting the female receptacle that Crown ships with the unit, or you can choose to find an adapter as I did. You may need to consult your electrician about all of this, but don’t let that stop you from looking into the Studio Reference 1. Aside from the gargantuan amounts of power the amp creates, it sounds just great as a full range device.

This came as a real surprise to me, especially since I used it that way before trying it as a subwoofer amp. It makes quite enjoyable music! The sound is neutral, fast, un-etched, and timbrally correct. On top of all that, the amp develops an astonishing soundstage with a very extended depth of field, width and stereo localization. I found the sonic performance to be sweet, uncolored and charming. On the Noah’s Flood disc by Britten, Noye’s Fludde, Norman Del Mar, [London (Germany) 436397-2] there are many examples of singers, both young and old, actively moving about the church space where it was marvelously recorded long ago. Those gyrations and staging effects were delivered outstandingly through this amplifier. If you know the “Harvest Moon” track from Cassandra Wilson’s, New Moon Daughter[Blue Note 32861] you probably have discovered the spatial details going on throughout the piece…the Studio Reference 1 let all of that come through, in eloquent fashion, in addition to the wonderful rendition by Ms. Wilson of this old time favorite. Big choral stuff as from Psalms, Turtle Creek Chorale, [Reference Recordings, RR-86] disc became entrancing, especially in allowing sectional placement of the singers to stand out almost holographically. I can go on and on about the range of positive attributes conveyed by this amplifier, but I think you can see that I really liked its performance abilities across the board.

Was there a downside? Yes, the Studio Reference 1 does use a cooling fan, which cycles on and off based upon workload. In my set up the amp was located about 10 feet away from my listening position, and I could hear the fan during quiet passages and between tracks. Sadly, it bothered me enough to knock it out of contention asthe solid-state amp to buy as a backup to my tube units. Quite frankly, if the fan noises were not present, I would have purchased this amp too. By the way, when implemented as a subwoofer amp, the Studio Reference 1 did not improve over the performance delivered by the K2, nor did it suffer in comparison. For less than half the money, the K2 stays as my pick for the subs and there is no fan noise to worry about, to boot.

I should note that in addition to drawing these overall conclusions in my own music system, I have the good fortune of hearing other top notch sound systems at the homes of many audiophile friends, often as a form of “reality check”. Some of those colleagues have likewise witnessed the improvements at my place and are in solid agreement with me about the findings reported here. Even better, when actually listening to live music, which I do frequently, I now feel better about how my system fares in that wholly unfair comparison. More joy abounds at chez T than ever before, and that means a lot.

In closing, I am very pleased to see an opportunity for the audiophile world and pro audio world to share excellent musical equipment. I believe that, in their appropriate applications, these two Crown power amps have done well by delivering very high quality sonic performance at decent price points. While these products typically will not be found at your local stereo shop, you might look into music equipment shops, pro audio dealers, or websites for such purveyors, including Crown’s own site, which does offer products for sale online. In addition, as a result of my previously noted interest in amateur recording activities over the last few years, I have become more aware of esoteric equipment that has been sequestered in the pro audio realm for some time. This includes many devices which recording engineers of the highest caliber depend upon. We occasionally witness the outcome of these brands of electronics on the CDs and records we buy. While many commercial releases are too compromised for the tastes of many purist audiophiles, perhaps due to overzealous record company executives or ill-informed producers, there are plenty of solid efforts out there. CDs from the likes of Reference Recordings, Chesky, Telarc, Harmonia-Mundi, etc., do reflect care, taste, acumen and a belief that recordings can indeed be better than most of the stuff foisted on the public. Perhaps as we learn more about the philosophies/practices of the pro world, including subjective and objective approaches, we can all benefit from a wider range of electronics, especially cost-effective items, which might solve home audio problems and desire. I, for one, hope so. Happy listening.

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One thought on "Crown K2 Amplifier and Studio Reference 1 Amplifier"

  1. Gaetan Perron says:

    i have 2 crowns k2
    here is how i used to operate them .
    either with my 12 inches infinity car sub reference 1230 in my living room and or
    with my double 15 inches proel pro sound
    and by far the k2 operate far better at 8 ohms either in stereo or mono stereo and or in bridge status
    mutch more stable and precise then in 4 ohms.
    to do so i would connect either my infinity in serie bacause they are 4 ohms
    or use the dual 15 in serie in each box also because they are 4 ohm
    and or connect 15 15 inches to speaker post left and right and use the mono stereo switch to mono
    that been said ,,, i was hooked to a 5 way stereo active x over
    the k2 were used from 0 to 80 hz
    i did test them at 16 ,8,4 and also 2 ohms in mono stereo
    the best by far is 8 ohms ultra tight and deep note, no blurr no boomy sound even with my infinity car sub bass refect.
    so definitly theses are real tuff to beat
    i was able to compare them with other pro audio amps such as
    qcs power lite 1800
    ev cp 4000
    mackie fr 2600
    mackie fr 1400i
    crest vs1100
    the ev cp4000 was also very good sounding but a bit more soft in the punch .
    so at the price you may be able to get one i truly recommend them .
    i had mine moddified with a switch to cancel the sleep mode so when you do not drive load they wont fall into sleep mode , wich can be irritating when listening soft music .

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