- Written by Jim Milton
- Published on 26 October 2009
- McCormack LD-2 Preamplifier and DNA-250 Stereo Power Amplifier
- Page 2: Design of the McCormack LD-2 Preamplifier and DNA-250 Power Amplifier
- Page 3: Setup of the McCormack LD-2 Preamplifier and DNA-250 Power Amplifier
- Page 4: The McCormack LD-2 Preamplifier and DNA-250 Power Amplifier In Use
- Page 5: Conclusions About the McCormack LD-2 Preamplifier and DNA-250 Power Amplifier
- All Pages
In 1997, McCormack Audio was purchased by Conrad-Johnson, known primarily for their fine tube amps and preamps. A new line of McCormack amplifiers and preamplifiers has since been refined and updated. They have the same high quality and value that Steve McCormack put into his designs in California, but these current products are basically an entirely new line (and are built in Virginia). The LD-2 (line drive preamplifier) and DNA 250 (two-channel power amplifier) are designed with the audiophile in mind, but at a price that puts it into the reach of the masses. This review offered me some interesting challenges and some surprising rewards. Did I mention I broke down and got an iPhone? I will explain why I mention this at the end of my review.
- LD-2 Line-Stage Preamplifier
- Gain: 20 dB
- THD: <0.1 % at 1.0 Volts RMS Output
- Hum and Noise: 100 dB Below 2.5 Volts RMS Output
- Dimensions: 3.5" H x 19" W x 11.25" D
- Weight: 18 Pounds
- MSRP: $2,495 USA
- LD-2 Optional Phono Stage
- Phono Sensitivity (Selectable):
- Low Gain: 5mv Input for 0.5v Output @ 1 kHz
- High Gain: 0.9mv Input for 0.5v Output @ 1 kHz:
- Low Gain: -80 dB Relative to 10 mv Input
- High Gain: -75 dB Relative to 100 mv Input
- DNA-250 Stereo Power Amplifier
- Output Power: 250 Watts/ch RMS into 8 Ohms, 400 Watts/ch into 4 Ohms at < 1% THD
- Sensitivity: 2.0V RMS for Full Rated Output
- S/N Ratio: 110 dB Below Rated Power
- Dimensions: 6.75" H x 19" W x 16" D
- Weight: 53 Pounds
- MSRP: $3,995
- McCormack Audio
The LD-2 preamplifier offers a high level of sophistication and refinement in the reproduction of music. It replaces the RLD-1 while retaining that unit's basic features. Unlike the RLD-1, the LD-2 uses a new Burr-Brown digital volume control instead of the Crystal Semiconductor controller. This volume control is more often found on more expensive preamps. The Burr Brown offers smooth and precise channel tracking.
One of the striking features of the LD-2 is the lack of knobs. The power supplies and connectors have all been upgraded, too. A Home Theater Bypass feature has also been added for those that wish to integrate the LD-2 into movie watching enjoyment. This bypass feature only works on the video input, which makes practical design sense. Volume is displayed in dB gain or attenuation and defaults to -50 when first powered up. There are 5 line level inputs: CD, VIDEO, TUNER, TAPE, & PH/AUX. It offers no digital inputs. This unit is analog only. A phono option is available to go with the LD-2 at an additional charge and there is no built in tuner. The unit does not power off completely unless you unplug it, but remains in standby mode. In fact, the remote does not have a power on/off button, which was something I missed.
When you hit a source input button on the remote, the unit will power up and resume with whichever volume level and input you used last. There are no tone controls on this unit, which is in keeping with the "purists" tradition. Two pairs of outputs are on the back so you can connect a powered subwoofer to the system. The outputs are wired in parallel and are electrically identical. I really liked the feel of the RCA connectors on the back panel.
When plugging in components, the connectors gave a solid "click" when the interconnects were snapped into place.These RCA connectors were the most solid and secure connectors I have had the pleasure to use in my experience. I hate plugging into connectors that wobble and "give" when you push an interconnect onto them. The front panel controls consist of "tactile" buttons that operate by touching and releasing. All functions can be operated by the remote as well. The display is large and can be seen easily from across the room. When muted, the display shows dash marks.
My overall impression of the LD-2 was that it is very well built and exudes quality and simplicity in design. The face plate is milled 0.25 inch aluminum. Believe me, neither of these units will flex when you lift them. The 3 prong power cord is removable on both units, should you chose to upgrade them later.
The DNA-250 is a 250 watt/channel amplifier that is based on the Distribution Node Architecture that contributes to the lighting fast dynamics the McCormack amps are known for. McCormack has over 30 years of solid state circuitry design in this amp. Rather than have a few very large reservoir capacitors next to each other, the DNA technique distributes many smaller reservoir capacitors among the output stage. This arrangement delivers a high degree of speaker control. The amp is heavy and the heat sinks make it somewhat challenging to grab and lift while holding it on the sides.
The main power toggle is located on the front. There is no trigger on the unit, so the pre-amp will not operate the amplifier. The amp is either ON or OFF as there is no standby.
The DNA-250 retains much of the signature McCormack "Distributed-Node" architecture, which puts individual capacitors right next to the output transistors for better performance. In the DNA-250, these capacitors are upgraded to conrad-johnson film-caps which deliver greater resolution and increased dynamic range. The DNA-250 incorporates completely re-engineered voltage gain and driver circuits well as a redesigned JFET input stage.
Judging from the heat radiating from the DNA, it must be sucking some wattage even in standby. A red light indicates that the unit is on, but does not change color to express a fault mode. Same aluminum faceplate and removable power cord as found on the preamp. Again, you can see and feel the quality.
The DNA-250 retains much of the signature McCormack "Distributed-Node" architecture, which puts individual capacitors right next to the output transistors for better performance. In the DNA-250, these capacitors are upgraded to conrad-johnson film-caps which deliver greater resolution and increased dynamic range and incorporates completely re-engineered voltage gain and driver circuits well as a redesigned JFET input stage.
I do not normally look inside my review products (a mortal fear of voiding the factory warranty!), but this is where the interesting part of this review kicks in. After setting up this system and test driving it with my Oppo 980H (analog outs, of course) for a few hours, I suddenly lost the sound. The LD-2 was on and not muted. The amplifier showed a red light, so it was on…but no sound. I did what any astute audiophile would do and shut it all down and "re-booted". Still no sound. I reconnected everything in a methodical fashion to no avail. Finally, I looked in the amps manual (why do we always do that last?) and read a blurb about blown fuses being a possible reason for loss of audio.
There are four +/- power rail fuses found on the underside of the amplifier. I opened the amp and replaced the 4 fuses ($1.99 for a bag of four at Radio Shack). Three of the four were definitely fried. Problem resolved. I had no further trouble with the amp for the duration of my review period. In all fairness, the blown fuses were most likely caused by something I did and was not poor workmanship on the part of McCormack Audio.
Well, as afore mentioned, I reviewed this system with my Oppo 980H. The analog outputs were used for both CD and SACD playback. For fun, I also used the output on my Samsung DLP for watching sports and movies via the video inputs on the back of the LD-2. ( I hate leaving inputs unused.) Somewhat complicating my review is the fact that I have just purchased new speakers; Revel F12s, so I am still getting used to their new "sound" in my listening room. They provide a full sound and the dual 8 inch woofers allowed me to evaluate the extension of the amps bass reproduction.
I was getting used to their sound with my Emotiva LMC-1/LPA-1 combo. The LPA is rated @ 125 watt per channel and at moderate listening volume; the output was on par with the DNA @ 250 watts per channel. So, how does one distinguish if the sound quality is the preamp, amp or speakers? Synergistically speaking, they all contribute. I know that people reading this article are going to want to know how the McCormacks sounded compared to another system (like my Emotiva), but I want to keep on track with the McCormacks sound and performance based on their own design and merits. (To answer the question: I am happy with the Emotiva LPA-1/LMC-1 combo as they meet my needs and I am incredibly cheap!)
All of my testing was done without the use of a subwoofer. For music, I picked out Copland 100 on the Reference Recordings label, an HDCD recorded and engineered by Prof. Johnson.
The tympani in this recording is one of the strongest I have ever heard recorded on disc. It is very deep with a good sense of acoustical depth. The McCormacks pulled out all of the nuances and details with ease. The soundstage was wide and deep. The music was very articulate and remained so with the volume being raised to extremely loud levels. Compared to my Emotiva system (Drat! I was not going to compare), the sound had a warm, almost "tube sound" quality. Very pleasant and easy on the ears. Bass impact was almost gut wrenching! Horns and strings were velvety smooth with fine detail like the ever so slight "stutter" that is heard when drawing the bow slowly across the strings....ah, bliss!
For variety, I played Jethro Tull: Thick as a Brick.
A complex mix of rock/jazz/vocal and instrumental noodling that was well presented by the McCormacks. The whole 44 minute recording is on one track, so pointing out specific standout sections is hard to specify. Suffice it to say it sounded great. Vocals and instruments were in a broad three dimensional space. The last recording was a disc that I think is out of print, called Sonic Fireworks Vol. 1&2. It was a direct to disc recording (recorded on location, without processing or editing) of brass, organ and tympani that has some startling dynamic transients.
The McCormacks played this stuff with aplomb. Deep, articulate bass and the shimmering crash of the cymbals made the hair on my back stand up! The reverb of the recording venue was well realized in my listening room. Really, if you are looking for something to rekindle your love for your old CD collection, this combination will get your blood pumping. I spent many hours just playing disc after disc. The McCormacks put me in my "happy place".
(Oh yeah, the IPhone. So after saying I would never succumb to the MP3 generation and its insistence on "convenience over substance", I downloaded a few of my favorite CDs and hooked them into the system. Wow! Not bad. When downloaded in a lossless format, the sound was quite acceptable. True, changing tracks was bit of a chore as there was not a remote for the phone. But for testing purposes, I could begin to see the ease and value of music played this way. You can impress an old dog with a new trick. It certainly will not replace my SACD player and I do not recommend buying the LD-2/DNA-250 just for your IPhone, but it was nice to have that as an additional option.)
I can not imagine anyone not being happy with the LD-2 and DNA-250. Their quality of build extends into their quality of sound. However, a few things should be noted. After extended listening, the amplifier was moderately warm to the touch and I would recommend placing it with good ventilation in mind. The width of each unit prevents a standard rack mount option. The remote seemed to be an afterthought by design, but it was functional. There are many other options out there for the cost of the McCormacks, but you could certainly do far worse things with your money and the McCormacks could easily become the last system you'd ever need for analog 2 channel listening. Well done!!