Terry London has always had a great passion for music, especially jazz, and has amassed a collection of over 7,000 CDs covering the history of this uniquely American art form. Even in his teenage years, Terry developed a passion for auditioning different systems and components to see if they could come anywhere close to the sound of live music, and has for the last forty years had great fun and pleasure chasing this illusion in his two-channel home system.
Terry is a practitioner of Rational Emotive Behavior Therapy by day, and runs the Chicago Institute for REBT. He has also authored nine books on this of type psychotherapy and education.
In the last year, several of my friends--whose "golden ears" I trust regarding which pieces of stereo gear produce superlative musical performance--came back from both the Newport Show and the Las Vegas T.H.E. Show raving about the virtues of the Perla Audio room. This piqued my interest to get in touch with Shane Duffy, President/Owner of Perla Audio in Sparks, Nevada, to set up a review. After our discussion, we both agreed that the Signature 50 integrated amplifier, which retails for $9,000, would be a good piece for evaluation for HTR.
During that conversation, Shane shared many aspects of the Perla Audio design team's overall principles, a historical perspective of how Perla Audio evolved its present generation of equipment, and finally the target sonic parameters that they shoot for in the performance of all their gear. There were two perspectives that guide the company's gear development that I found quite striking. First, their chief designer, Ronald Van Robinson, is given total freedom, regardless of cost, to experiment with and use any component/part that will produce the overall sonic reproduction that the Perla Audio team feels to be the closest to live music. Second, no time restraints were placed on the development of the Signature 50 in order to get the performance that the team wanted.
The Signature 50 weighs 44.2 pounds and measures 5.8 inches high by 14.5 inches wide by 18 inches deep. The chassis is CNC-machined out of solid billet aluminum that has been anodized with a satin black finish. In the middle of the front plate is where the main on/off switch is located, flanked on either side with large solid knobs that control inputs and volume levels. On the back plate is where you'll find the IEC power input, two RCA outputs to run subwoofers, three RCA inputs, and two pairs of very high-quality speaker cable terminals.
The internal design/circuit has many innovative features, such as no capacitors in the signal path, a true dual mono circuit, and a power supply capacitance of 376,000uf using 80 electrolytic capacitors and 84 polypropylene capacitors. Additionally, the amp also has custom-made 3.35mm-thick 2oz copper 24k gold plated PCB boards using Cardas ultra-pure quad eutectic proprietary solder and two 160VA toroidal power transformers encased in 2.6mm steel cases. The Signature 50 is rated to deliver 50 watts into eight ohms and 100 watts into four ohms of what Perla Audio calls "rich" Class A/B. The remote control is also constructed out of anodized black aluminum with a carbon fiber front insert with two buttons to control volume up/down. The physical appearance of this integrated amplifier is low key and demure; however, its extremely high level of build quality and clean lines emit a picture of understated elegance.
To power my large reference system, I use a pair of Pass Labs XA-60.8 mono blocks and the Concert Fidelity LS-080 tube-based preamplifier. This combination creates a beautiful fusion of the utter transparency, speed, micro-details, and slam/power of solid state with the rich tone, colors/timbres, liquidity, three-dimensionality, and space that are created by tube-based designs. When I inserted the Signature 50 in place of the above-mentioned components and cued up the baritone saxophonist Gerry Mulligan's Concert Band Sessions (Mosaic), I had to do an "auditory" double-take. The soundstage stretched from sidewall to sidewall with all the members of Mulligan's big band in their right positions. The individual players were rendered with a lifelike three-dimensionality, with space and air in between them and their bandmates. The horns' brassy tones/timbres were reproduced in a very compelling, vivid, and natural way. All of these parameters matched the sonic signature of my reference solid-state/tube combo. In a blindfold test, I do not believe I could tell the difference between my separates and the solid-state Signature 50 integrated amplifier. The retail cost of my combo is $34,800, and yet its performance was being matched by the drastically less expensive Perla Audio Signature 50.
My next selection was Adele's breakout album 19 (Columbia) to see how the Signature 50 would handle reproducing the greatest and hardest instrument to get right: the human voice. The Signature 50, like the Pass Labs .8 series, has virtually no noise floor and allowed me to easily hear every nuance of what Adele was doing with her voice in the studio when she made this recording. These fine details were never presented in an analytical or artificial way, as if listening under a microscope, but were woven into the overall tapestry of her powerful voice. As far as rendering the unique timbres/tone of her voice (which allows you to identify what emotion she's trying to convey), the Signature 50 was up to the task in creating an intimate "feeling" connected to what Adele was trying to share in her music.
Finally, I wanted to test how well the Signature 50 would do in the areas of slam/punch, bass extension, and overall micro-dynamics. Sotho Blue (Sunnyside), a recent album by the highly regarded South African pianist Abdullah Ibrahim and his group Ekaya, was recorded at a very high reference level with world-class dynamic range, deep extended impactful bass, and transient speed. Amazingly, the Signature 50 was able to effortlessly reproduce the "kick" and "pop" of this very dynamic recording, considering it was only rated at 100 watts into four ohms. My explanation for this would be that the very sophisticated and robust power supply, along with being a dual mono design, gave the Signature 50 the reserves to handle the macro-dynamics in a spectacular manner and render this aspect of the music with an iron-clad grip and impact.
• The Perla Audio Signature 50 integrated amplifier is hand-built with the finest parts and has many innovative ideas incorporated into its design. Its physical appearance is clean and straightforward; however, its beautiful construction gives it an understated, classy look.
• The Signature 50 offers superb transient speed, macro-dynamics, crystal-clear transparency/micro-details, and tube-like, rich, and deep tonality/timbres for the different instruments it's reproducing.
• It produces virtually no heat and, therefore, can be placed in a closed rack without any problems.
• Also, it can power most speakers used today in either a home theater setup or two-channel system to very high volume levels with no compression of macro-dynamics, thanks to its unique power supply.
• Finally, it saves the added cost of a pair of high-quality ICs and is shipped with an in-house-built power cord that rivals the performance of high-cost, after-market power cords.
• The Signature 50 does not have a theater bypass option.
• It only offers RCA single-ended inputs/outputs and would not allow you to use your cables that are XLR/balanced designs.
Comparison and Competition
Two integrated amplifiers that I have direct experience with and are in the same price category of the Signature 50 are the Ayre Acoustics AX-5, which retails for $9,950, and the MBL C51, which retails for $11,200. In the case of the Ayre Acoustics AX-5, two shortcomings were very noticeable. First, the transparency/clarity of the Signature 50 was at a much higher level than the Ayre Acoustic AX-5. The small details were harder to hear through the AX-5. It almost seemed like there was a slight haze getting in the way of the music. Second, the Signature 50 had a great advantage in transient speed and power compared with the Ayre Acoustic AX-5. When I compared the Signature 50's beautiful, rich, and warm tonality and overall liquidity/ease to the slightly more expensive MBL C51, what I quickly became aware of, and found quite annoying, was the MBL C51's rather sterile and much drier rendering of tonality/timbres with any music selection that I used compared with the Signature 50.
The Perla Audio Signature 50 has many superlative qualities to offer the music lover searching for an integrated amplifier. These would be its overall build quality, selection of internal components, materials used for its chassis, and innovative design strategies. When it comes to the Signature 50's sonic performance, it offers one of the finest syntheses I have experienced in terms of offering both the transparency, speed, dynamics and control of great solid-state gear and the beauty of rich, dense tonality/timbres along with the air and three-dimensionality that tubes can produce. I am still amazed that it equals the performance of my much more expensive mono-block and preamp combo. I have purchased the Signature 50 to power my smaller upstairs system because of its stellar overall performance.
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