AOM Logo July 2008

 
The NuForce P-9 Preamplifier

Henry Wilkenson

 

 


I have always taken a keen interest in pre-amps and line-stages, since I consider them to be the heart of a typical system. Years ago, pre-amps were the big stars of the system. Often they were outfitted with enough knobs and dials to rival a small flight deck. Some manufactures even through in graphic equalizers that would light up and dance to the music. We have come a very long way since those days however, a few manufactures still include balance controls, phase reversal and head phone jacks. Others still provide phono stages. The typical pre-amp of today is a line stage that provides little more than a volume control. Many would agree that the music is better served this way.

NuForce has been releasing one well received product after another, since their inception. Well, Jason Lim and company have done it again with the P-9 preamp. Since NuForce intended the P-9 to be their flagship preamp, Demian Martin was brought in as the chief designer of the P-9. Demian Martin has a long history in the audio industry. As the co-founder and Director of Engineering of Spectral Audio, he was responsible for the design and engineering of many of Spectral’s now classic designs such as the DMC-10 preamplifier. Many of you already know that many of Spectral’s products set new industry standards at the time. The P-9 is a two box unit, (not very unusual for high-end line-stages these days), that is slightly larger than the company’s 9-SE power amps. After becoming very familiar with the NuForce power amplifiers, I was very anxious to audition their latest top of the line pre-amp. As you will see, this is a very special component in its own right.

Background

According to the manufacturer, the P-9 is designed to be a low-noise high-performance component. The two box design goes further than simply housing the noisy power supply in a separate enclosure. Since the P-9 uses three separate power supplies, all of them along with the microprocessor control logic are contained in the control box. All of the analog circuitry is contained in the analog box. In order to achieve a very high degree of isolation, the amp modules operate within heavy copper shields with internal thermal insulation. Analog signals only pass through the analog box. The P-9 features an all discrete precision amplifier module employing ultra low noise, monolithic dual JFETs, specially selected MOS FETs and very flat hEE bipolar transistors in a dual-cascade design with a driven shield to reduce capacitive loading on the final voltage amp. All of these features combine to give the P-9 a S/N ratio in excess of 100db and a dynamic range in excess of 120 db. Essentially, these circuits are as complicated as they are unique. A number of peripheral circuits are used to stabilize the main circuit. The result is a component that is very stable and quiet.

Set Up

The two boxes weigh in at a combined weight of 13 pounds and measure 1.76”H X 8.5”W X 16”D. As with all NuForce gear, they make very modest demands on valuable shelf space. Installing the preamp is quite easy but while it is extremely difficult for the average audiophile to do, it is advisable to read the owners manual first. It is most important to connect the 15-pin DC and control cable between the two boxes before powering up the unit. Should you wish to place the boxes further apart than the cable will allow, you must obtain a longer cable from NuForce. The control cable may look like a typical VGA cable used for computer monitors however, there is a significant difference. The P-9 uses all 15 pins in the cable; since all of the pins in a typical computer cable are not connected, they will not work with the P-9. The P-9 must be fully powered down while connecting source components. Once your connections are made, then you should connect the power cord. I should mention that the supplied power cord is not a throw away. It may not look like much but, it is in fact a high quality power cord. Experiment with other cords if you will but hang on to the supplied cord until you are sure another one actually makes a sonic improvement.

Layout

The layouts of the front panels of the P-9 are very clean and straightforward. Along the front of the control panel you will find the input selector on the left which also is used to turn the P-9 on and off. Actually, this on/off control turns off the analog box while the control box remains active in standby mode. The volume knob is on the right and also activates the mute function. The master on/off switch is on the rear panel. The P-9 has a total of three volume controls if you count the one found on the remote. The analog box has only one knob which is another volume control.

The rear of the analog box from left to right contains the dc connector, one set of balanced and one set of unbalanced (RCA) outputs. Both outputs can be used simultaneously for bi-amping. Next are five RCA inputs. Input number five is a standard input when the P-9 is active. It is a direct bypass when the P-9 is turned off. This will facilitate other components that have their own volume controls, such as a home theater processor.

The remote control is an eight inch hexagonal “stick” that allows you to control all of the P-9’s controls. Caution should be used when installing the batteries. Use a #3 Philips screwdriver (a nylon tipped screwdriver would be best) to remove the only Philips head screw on the bottom of the remote. A deft touch is required here since this screw is easily stripped. Once the screw has been removed, gently slide out the base plate to expose the battery holder. Be careful to properly line up the screw holes once you install the batteries then carefully re-install the screw. Overall, this remote is a very user friendly design.

Sound

This is another component whose sonic character is easier to describe by listing what it doesn’t do. There is a total absence of hardness or edge, no transistor nastiness here. More importantly, the timbre densities of instruments are full and rich but do not have the midrange bloom of some tube designs. No, you will not confuse the sound of the P-9 with classic tubes or single ended triodes but neither does it sound bleached or sterile, as do much of the transistor gear in its price class. I particularly noticed how well recorded piano music is presented. The harmonic overtones as well as the shimmer and decay of notes were presented very nicely. This is particularly noticeable with good recordings such as Keith Jarrett’s “My Foolish Heart, Live at Montreux”[ECM 2021/B0009897-02]. In addition to the well recorded performance, you get a good sense of the hall as well.

The extremely low noise floor is largely responsible for the greater revelation of low level detail. Even familiar recordings have information revealed that went unnoticed previously. Fortunately, this detail does not come with a hyped or harsh treble. It’s just that I was hearing more information with the P-9 than before. This can also be a double edged sword in that poorly recorded sources are ruthlessly revealed for what they are. This is also true of any associated equipment that you choose to connect to it. Interconnects and power cords will make a substantial difference to the sound. You will readily hear what they are doing for better or worse. You would be wise to carefully audition any potential candidates.

This low noise floor is probably also responsible for this pre’s amazing transparency. I know that you have heard this said many times before but, I did have the sense that I could hear into the stage. All of the above performance characteristics combine with the P-9’s outstanding imaging to provide a truly thrilling listening experience.

The treble is naturally extended. Bell tones and cymbals are clear with very good shimmer and decay. The different timbres of cymbals are a pleasant surprise. This is the kind of musically relevant detail that I always welcome.

The mid-range is clear and open. The lack of noise brings the added benefit of increased transparency. Coupled with the outstanding sound staging that NuForce products are known for, you wind up with a very open stage with instrumental images well placed from left to right. Front to back layering is quite good. This makes live recordings more enjoyable. Overall, I found little if anything to fault sonically with the P-9.

The bass is full, deep and articulate. Excellent bass performance seems to be a family trait of NuForce components. The textures and articulation of the upright bass is captured as well as the bloom of the same instrument in its lower registers. With organ music, the P-9 will take your system as low as it is capable. The P-9 had no problem shaking the walls. Whatever I threw at it, the P-9 handled with ease.

Summary

Impressive is one of the ways to describe the NuForce P-9. Given its stellar sonic performance and its price point, I can honestly be call it a bargain. Of course, if your tastes run toward the sound of vintage tubes, I would suggest that you look elsewhere. Is the NuForce P-9 absolutely the very best thing out there? Well, no. There are better to be had, but, be prepared to pay at least three times the price of the P-9. If, however, you are looking for a very high performing linestage whose predominant sonic signature is neutrality and you want it at a very reasonable price, do not overlook the Nuforce P-9.

 

 

Associated Components

Analog Source: VPI HW-19 IV MK 4 turntable; Rega RB-700 Tone Arm and Benz Ruby 3 Cartridge
Digital Sources: SONY 777ES SACD player
Amplification:VAC Standard LE Pre Amp; Gilmore Raptor Mono Blocks
Loudspeakers: Dynaudio 3.3
Cabling: Wasatch Ultama Speaker Cables; Acoustic Zen, Siltech and Wasatch interconnects and speaker wire
Accessories: P.S. Audio Power Plant P-300; Echo Buster Panels

Manufactured by NuForce

356 South Abbott Avenue
Milpitas, Ca. 95035

Price

MSRP $3100 3 year non transferable limited warranty on parts and labor

E-mail: salesteam@nuforce.com

NuForce website

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