Publisher Profile

Understanding The Gentle Mind Behind Alex Peychev Laboratories Hi-Fi And His Quest For The Ultimate

System Profile #3

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Spotlight APLHiFiFrom The Top

Alex Peychev’s Esoteric retrofit work under the APL Hi-Fi banner was in such constant demand, that for the two visits I paid him in the space of three months in mid-2007, his backorder status did not slow down. In fact, there were eight Esoteric players waiting for him to work on, and I had the most fortuitous opportunity to listen to one of the Esoteric UX-1 players that came smoking fresh out of Alex’s laboratory in my system for two days.

Alex Peychev Laboratories Hi-Fi has been the source of a considerable number of enhanced Esoteric digital players for the past few years, and a particular blog section of its website documented the creation of APL Hi-Fi’s latest incarnation of machines based on redesign of progressive generations of the Esoteric VRDS (Vibration-Free Rigid Disc-clamping System) disc transport, the latest of which being the VRDS NEO mechanism.

Alex is an Electronic Engineer with a fast-tracking career background. In 1988, when he graduated fresh from an electronics university in Bulgaria, he started working as a technical consultant for a former West Berlin audio/video company for three years before coming to the U.S.

Once in the U.S., after working briefly for a Mountain View, CA a/v company, Alex was recruited by Sony Electronics and began to work his way through the electronics giant’s Consumer Division to the Broadcast and Professional Division. He became their Senior Lead Electronics Engineer.

Alex eventually left Sony in 2003 and founded APL Hi-Fi to pursue his dream.

Drawing from a uniquely thorough understanding of not only the properties of a vast selection of electronic parts but also their strengths, characteristics and their interactive relationships, Alex looked at some of the more promising digital players on the market and replaced their circuits with his own designs and took them to shows. Some of his early works were on Denon digital players, and soon exuberant audiophiles began to spread the word.

One of his digital players that received the most attention was an Esoteric UX-1 that he worked on, the word-of-mouth performance of which prompted the very top brasses from an exhibiting Esoteric at CES 2006 to visit his Exhibit and experience the buzz of the show for themselves. The mutual admiration that transpired afterwards was the stuff of a legacy in the making.

Today, APL Hi-Fi is revered by many for its retrofit work on high-end Esoteric digital players. Various levels of APL Hi-Fi technology are available for various budgets, beginning with the NWO-1 at $20,000, with the price already being inclusive of a new Esoteric UX-1 SACD/DVD-Audio/Video player. The higher-level APL Hi-Fi players are priced at $25,000 for the NWO-2.5T upgrade, plus the latest and greatest, cost-no-object NWO-3.0GO at $30,000. For customers providing their own Esoteric UX-1 players, the cost of transforming the Esoteric into an APL Hi-Fi NWO player is $10,000 for the NWO-1, $14,000 for the NWO-2.5T and $19,000 for the NWO-3.0GO.

The brain of the NWO-3.0GO

Picture above is an exclusive APL Hi-Fi construct that houses the 40 Asahi-Kasei DAC chips.
Every component and wiring is handmade by Alex Peychev personally.
A full week is needed to construct this single miniature structure.
Each APL Hi-Fi NWO-3.0GO contains this structure.

Short for New World Order-3.0 Game Over, the latest of Alex Peychev’s work signifies his confidence that no other player in existence today contains craftsmanship and technology with the resultant performance envelope that can surpass his. The APL Hi-Fi NWO-3.0 GO is an Esoteric digital player with all APL Hi-Fi proprietary circuits and technologies, and with only the Teac VRDS-NEO transport in the Esoteric UX-1 chassis intact as carried over from the original machine.

The substantial APL Hi-Fi-branded redesign included a completely new signal-processing circuit. According to Alex, whereas most companies adopts transport and DSP assemblies from Philips, Sony, Sanyo, Panasonic and Pioneer, he uses a highly upgraded and redesigned system using a proprietary 211kHz/32bit upsampling scheme based on the DSD/DVD-A capable DAC chip by Asahi-Kasei, named AK4397, in an employment of 20 of them per channel. Alex then conducted extensive listening tests with APL Hi-Fi customers. With the additional aid of measured and sonic evaluation, Alex then settled on converting DSD (SACD) signals to a 176.4kHz/24bit PCM format. According to Alex:

“This truncates DSD in theory but I don’t feel it is audible to the human ear. What is audible is the interaction of the huge amount of out-of-band noise with the top-end of the audio spectrum resulting in artificial smoothing, and the non-linear phase in the hearing range caused by the necessary filtration in the analog domain with “Pure DSD”. Converting the DSD to PCM takes care of these problems. Furthermore, all formats played on the NWO are upsampled to 211kHz/32bit so the AK4397 DAC’s work all the time at this rate. Inside the AK4397 DAC’s, the 211kHz is oversampled 8 times in the PCM domain, then it is converted to Multi-Bitstream signal (5 bit, not single bit like DSD is) and upsampled 4 more times for the total of 32 times. This results in final sample rate of 6.752MHz with linear phase and extremely low out-of-band noise.”

The new power supply for Alex’s DAC system and the Teac VRDS-NEO mechanism includes a custom Lundahl audio transformer-coupled class A tube stage with a pair of ECC99 tubes. All circuit boards are hand-populated laboriously without use of a single machine, and all connections are “hand-soldered point-to-point”. Finally, the use of a remote-controlled H-attenuator at 0.5dB increments negates the need for a preamplifier.

The amenities don’t stop here. On top of all these, the APL Hi-Fi NWO-3.0GO is equipped with either an BNC or RCA digital input that accepts up to 192kHz/24bit digital signals, essentially empowering its capability further in acting as the hub of connections for computer audio, cable box, satellite receiver, etc. without the need for a preamplifier. Then, the NWO-3.0GO can be further endowed with an $1,000 option that consists of an AKM Analog-to-Digital converter that converts incoming analog signal from a phono stage to an 192kHz/24bit digital stream. Alex claims absolute sonic transparency for this conversion. In a simple statement, Alex claims that, “Sound quality is unmatched in my opinion. When it comes to craftsmanship and end-result, the NWO-3.0GO can be compared only to the most expensive all-hand-made Swiss watch of the highest quality.”

The NWO-3.0GO is also my statement work when it comes to digital player designs, cost no object. – Alex Peychev

Alex also has a very macroscopic perspective on the Teac VRDS NEO, a transport that, in his belief, is “light years more advanced”. Alex:

The VRDS-NEO sits next to a stack of Pioneer, Philips and Denon transports
(Picture courtesy of APL Hi-Fi: http://www.aplhifi.com/VRDSNEO/VRDSstack)

“The VRDS-NEO is made from very thick non-magnetic precisely machined stainless steel and aluminum. The actual spindle motor is made of extremely durable and lightweight Magnesium platter which is the same diameter as a CD. It clamps the entire top side of the disc and spins it. The Magnesium disc has a precisely installed Neodymium magnet on it and is attached to the 1 inch solid stainless steel bridge assembly with 2 high quality ball-bearings. This ensures vibration free high speed rotation of the disc. The ‘motor’ assembly is a high-torque, high-precision brushless motor which spins the Magnesium disc from a distance (about 2-3 millimeters). There is no mechanical connection between the ‘motor’ and the Magnesium disc. This is unbeatable solution which is free of any problems usually associated with spinning the disc.

The Laser Pick-up assembly is also very unique. It is mounted on 1 inch machined solid Aluminum base and travels on two stainless steel rods. The laser pick-up is being moved by high-precision brushless tracking motor similar to the one that spins the disc. The most unique part is that the focus lens on the top of the laser pickup is not suspended on anything else but……air. Unlike any other design, the focus lens is suspended on a magnetic field. The lack of mechanical suspension parts makes possible for an extremely accurate and super-fast focusing of the laser beam. Since the laser lens does not only focus but also tracks the pits of the disc, the designers have implemented radial tracking in this unique device. In other words; there is nothing like it.

Besides the mechanical superiority of the VRDS-NEO transport, its electronics companion, the Digital Signal Processing (DSP) board, is also of the highest possible quality. The DSP uses the best devices by Sony Electronics ensuring unbeatable processing quality. The disc rotation speed for all digital formats being played on the VRDS-NEO is much higher than normal. This provides many benefits but the most important are:

1. Since the reading speed is much higher, the audio data is being stored in large SDRAM memory buffers. The audio data is being clocked out of the SDRAM which effectively eliminates jitter coming from the transport.

2. If reading error occurs (imperfection on the disc), the laser assembly can be sent back to the problematic passage to re-read the data and try to correct the error. This happens while you are listening to uninterrupted music coming from the SDRAM buffers. In other words, the VRDS-NEO is capable of extremely powerful error correction, including the so called RUR (Read Until Right).”

In addition to completely redesigned electronics surrounding the Teac VRDS NEO mechanism, the APL Hi-Fi players also feature DIGITAL INPUT accepting up to 192kHz/24bit of digital signal, effectuating the use of the player as a standalone DAC as well. The players can also be fitted with an ANALOG INPUT section for an additional $1,000, making the player the central hub between sources and the power amplifier with its variable analog output. Incidentally, APL Hi-Fi’s technology can also be incorporated into Esoteric’s X-01 Super Audio CD player with the same performance enhancement for the same price points, sans the video output of the UX-1.

System Foundation

The two-story garage behind Alex’s house served as the APL Hi-Fi sound room upstairs and the laboratory downstairs. The sound room measured 20 by 20 feet with asymmetrically sloped ceiling, arguably one of the least ideal rooms for sound reproduction; and here is where Alex flexed his creative muscles. He lined the front wall with columns of Home Depot fiberglass rolls, and positioned fiberglass rectangular panels at reflection points and corners. There is more:

“… pair of Shakti Hallographs to the rear side of the speakers, acoustic foam in various places, 3 pairs of Silver Acoustic resonators, one Platinum resonator in the middle of the soundstage, and one Gold Special resonator behind the listening position. The resonators are made by Franck Tchang Acoustic Systems.”

The APL Hi-Fi Reference loudspeakers were further voiced in such a way that they were placed 10 feet apart near the middle of the room, with the right speaker a few inches closer to the right wall than the left speaker was to the left wall. The right speaker was also a few inches closer to the listening position than the left speaker. The resultant sonic properties of this room was at once most exemplary, customized to showcase the Reference loudspeaker.

A modular design, the Reference loudspeaker was a 3-way design featuring a Scan-Speak Revelator tweeter, two 7-inch Revelator mid-bass drivers, one 10-inch side-firing woofer – all in their own separate enclosures. On the creation of this reference-caliber loudspeaker, Alex offers the following:

“Just like the NWO-3.0GO player and my hybrid amplifier, the speakers are product of my 25 year search for perfection. The first speaker pair I’ve designed and built was around 25 years ago in Europe, Bulgaria. They were 3-way speakers with paper cone woofers and mids, the tweeters were horn loaded ribbons. When I came to USA 14 years ago, I started searching for the best-sounding drivers and went through many – Peerless, Vifa, Focal/JM Labs, Fostex, Lowther, Dynaudio, Morel and many other highly respected ones. Then I learned about the new (at that time) Scan-Speak Revelator drivers featuring laser cut paper cones and the Revelator tweeter with textile dome. Hearing these drivers for the first time was like a dream come true for me! I’ve never heard more natural tone out of any other drivers I’ve evaluated. Then it came the crossover….in my opinion, the crossover has to be 1st order because anything else takes away from the audio quality. It took me almost a year to tune-up the crossovers which are impedance and resonance corrected.

Each speaker is made of 3 enclosures – one for the side-firing 10-inch woofer, one for the two 7-inch Revelator mid-bass drivers and Revelator tweeter configured in MTM. The last smaller enclosure holds another Revelator tweeter used as a super-tweeter. This is the latest Revelator tweeter featuring dual concentric dome and phase plug allowing 40kHz top extension. The overall height including feet and super tweeter is 52 inches, width is 10 inches and depth is 17 inches. We recommend Cherry finish as it sounds best in our opinion, but other finishes are available too. Weight is around 100 pounds each. The sensitivity is around 88-89 dB, but because of the 10-inch woofer, a powerful high-output current amplifier is required.”

The APL Hi-Fi Reference loudspeaker system with custom cabling.
Person in the background: Doug Olsen

In the APL Hi-Fi laboratory downstairs, a large pillar positioned directly at the central point of the ceiling was erected to strengthen the flooring of the listening room upstairs. This served to compliment the bottom-end resolution of the APL Hi-Fi Reference loudspeaker.

Muscular Refinement

To bring out the full potential of his loudspeaker, Alex did not resort to using any of the amplification products in existence and instead created one of his own. According to him, he designed 50 amplifications of both solid-state and vacuum-tube varieties in the past 25 years, and his first project as a child was a 25Wpc using Germanium transistors because “Silicon parts weren’t wide available at that time”. His quest for the perfect amplifier that would bear his company’s name took a different turn 7 years ago:

“I was working at Sony during that time so I’d get back home from work at around 5 pm, drink coffee and build my amp till 1-2am. It took 3 months and $8K to build this masterpiece. It has 2500W power supply with 250,000uF storage and is capable of 44 Amperes current output per channel. The tube gain stage uses 6SN7 (VT-231) tubes at the input coupled to 2A3 Direct Heated Triodes (DHT). I’ve tried 45 and 300B tubes, but the 2A3 sounded most linear to me. The tube stage runs on regulated voltage done with one 6AS7 tube per channel. The tube stage is entirely DC coupled so there are no interstage coupling capacitors.

I am using a coupling transformer in this amplifier. It was custom made for me by the English audio transformer guru Brian Sowter. The single-ended tube signal is converted to Balanced by the Sowter transformers. The current buffer is made with unique solid-state devices and topology. There are 4 high current amplifiers per channel: Two by two paralleled and then bridged providing balanced output power capable of driving even the most difficult speakers. The output power is 350W per channel at 4 Ohms. The amplifier is Non-Negative Feedback design and is all hand made with point-to-point connections, including the PCBoards.

This is my statement work when it comes to amplification, cost no object. I am planning to release it in the future as a boutique bundle product together with my speakers and cables. Cost is TBD. This would be the most perfect companion for my NWO series of universal digital players in the case best audio quality is desired.”

I was treated to a full APL Hi-Fi sound demonstration, complete with Alex’s own Reference hybrid amplifier, Reference loudspeaker and the NWO-3.0GO. Despite the singular, visually somewhat unsettling loudspeaker placement in the room, the sound of the room reaching the listening position proved to be truly spectacular. I heard highly uniformed spectral linearity with spacious soundstaging. Because of the painstaking efforts Alex and his friends made in tuning the room, it was transformed from a nightmarish scenario into a sonically majestic sound room.

When playing the Deustche Grammophon’s 1982 release of the late Herbert von Karjan’s reading of the Richard Strauss tone poem, Also Sprach Zarathustra, Alex’s system created the highest level of instrument differentiation I’ve experienced, separating the supple, thunderous organ in a level of clarity as I have never heard, fully complimentary of the equally distinct sound of the various instrument groups. This was the most spectacular reproduction of my beloved music, at a level not even my own system could approach. The APL Hi-Fi reference loudspeaker is a thoroughly customized monitoring system created specifically to perform at its best when driven by Alex’s reference hybrid amplification system. When opportunity permits, I shall also share my own experience of its sound in my house with our readers.

Meanwhile, watch for a review of the APL Hi-Fi NWO-3.0GO soon in these pages.

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