I now list the best CDP that I've ever owned. That includes the likes of BAT VK-D5SE w/ Super-Pak, EMM Labs CDSA SE, Marantz SA-7s1 amongst many others. This started life as a standard Marantz SA-11s1 which was then sent to Chris Johnson, formerly of Sonic Frontiers, who now runs Parts ConneXion. Chris performed his $3190 "Ultimate tube mod" which goes something like this: The Ultimate for the Marantz SA-11 [$5,990 for new machines, $3,190 + freight retrofit] can be broken down into 3 parts:
Part 1: The "new" PCX-designed fully differentially balanced tube output buffer stage is installed with concurrent output via both RCA and XLRs, which has its very own, dedicated power supply PCB and toroidal power transformer - 3 modules in all. This module was conceptually designed by Chris Johnson, Sonic Frontier's (SFI) founder and former president. The actual circuit design and electro-mechanical integration was developed by two of SFI's former senior designers , Glenn Dolick and Zdenko Zivkovic. (This vacuum tube-based output buffer stage can be installed into any player which has physical space for all 3 component parts. Although it was designed to be used with DACs which have differential output per channel, we can also install it into units which have traditional single-ended output.)
Two-tube capacitor-coupled circuit which can use a variety of tubes including 6DJ8s, 6922', 7308s or any of their derivatives (ships with ElectroHarmonix EH-6922s). It can also be used with the Russian super tube, the 6H30 made famous by both BAT and later, ARC. Parts quality is superb. We use 5uf AuriCap output coupling caps with Rel-Cap TFT Teflon bypasses; premium Azuma gold-plated ceramic PCB tube sockets; Riken precision carbon comp resistors; Audio Note tantalum resistors; Cardas PCB-mount RCA jacks; Neutrik gold-plated XLR connectors Multiple fully regulated power supplies all on their own distinct power supply PCB, featuring Black Gate electrolytic caps in critical locations and IR Hexfred ultra-fast soft recovery diodes Our own custom-made 200% duty cycle, low noise, low stray field toroidal power transformer.
Part 2: Our Level 2 deluxe mod is performed on the first two (of three) stages to the Marantz's overall analog output stage - the I-V (current to voltage) stage, the analog filter stage and associated Marantz power supply, which supplies these two stages. We do not modify Marantz's proprietary HDAM output buffer module/section as this is what is bypassed in favor of our proprietary tube output stage.
We upgrade the hypercritical I-V and analog-filter op amps, replacing the cheap, stock surface-mount parts (currently about 50 cents each from JRC) with the very best dual op amps offered by Burr-Brown, the OPA-627-AUs, mounted to special SMT-to-SMT vertical adapters (which are 50 times more expensive than the stock part). These parts dramatically enhance both the unit's technical and subjective audio performance. The SA-11 Ultimate still uses 4 (not 6 as in the Level 2) of these dual opamp upgrade modules (2 were not needed as we now have the tube output buffer stage). For comparison purposes, op amps of this quality are usually found in 2-channel products retailing for $5,000 to $10,000! This upgrade alone is analogous to upgrading a car from a 4-cylinder to a V12 twin-turbo! The output signal currently exits these stages via a minuscule tin/lead plated printed circuit board (PCB) trace. However, in our mod, we instead use both shielded interconnect and hookup wire which contains 99.999% pure, long-grain 23-awg solid-core silver DH Labs wire with foamed Teflon tape-wrap insulated (the very best) The critical signal resistors (22 in all) are changed to precision Japanese made Riken Ohm Carbon comp types with gold-plated copper leads. These replace the cheap, magnetic, China-sourced metal-film resistors in the stock unit All critical caps changed to the best Film and Electrolytic types: Black Gate FK and N Series caps (5) replacing the cheapest quality generic electrolytic caps in the stock unit Precision 1% polystyrene film and tin foil caps (14) are installed in the analog filter stage, replacing cheap tantalum caps in the stock unit The power supply has been upgraded with 9 Black Gate FK, NX, STD series electrolytic caps (replacing cheap ceramic and/or generic electrolytics) and all critical analog supply diodes (currently generic quality) have been replaced with ultra-fast soft-recovery Fred-type diodes 4 Vishay-Telefunken and 5 International Rectifier Hexfreds A pair of small Bybee Slipstream Quantum Purifiers are installed in the power supply just after the IEC inlet, in line with the transformer primary windings. These noise suppression devices work at a quantum level, helping quiet the power supply, allowing for a blacker background, which promotes increased perception of dynamic contrasts.
Part 3: Chassis upgrades are performed to add necessary ventilation, damp chassis resonances, isolate the unit from external and internal vibrations and shield from both RFI and EMI.
The chassis resonances have been dampened with SoundCoat (2 sheets-1sq. ft) External vibrations have been isolated via (4) large compliant Ear Sorbothane feet ERS EMI/RFI paper is placed in critical locations to suppress stray EMI and RFI fields within the unit We use WBT 4% lead-free silver solder throughout.
The upgrade mod and custom tube stage installation takes upwards of 14 hours to complete when you take into account unpacking, disassembly, chassis remanufacturing, PCB module assembly, component part upgrading, reassembly, testing and repacking.
Then it was sent to Joseph Chow of Audio Horizons/Component Plus for an $800 mod. From what I understand, most of this mod was for the digital balanced (XLR) output, which I did not use. This CDP sounds as good as any digital that I've ever heard and I hate to part with it. It has only balanced outputs, but I will include a pair of Tara Labs XLR>RCA adapters at my asking price. You can pay more money, but you won't get better sound. Rated 8/10 just for age.
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