audio:audio_by_van_alstine_work
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audio:audio_by_van_alstine_work [2019/08/02 20:44] – [The future] mithat | audio:audio_by_van_alstine_work [2019/08/02 23:02] – [The present] mithat | ||
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====== Audio by Van Alstine work ====== | ====== Audio by Van Alstine work ====== | ||
- | I have done quite a bit of consulting work for [[https:// | + | I have done quite a bit of consulting work for [[https:// |
- | The focus of my work with AVA has always been to bring the highest standards of audio engineering to the company while fostering | + | The focus of my work with AVA has always been to bring the highest standards of audio engineering to the company while helping to foster |
===== Transcendence Five ===== | ===== Transcendence Five ===== | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | New vacuum tube line stage to replace AVA’s existing design originally derived from the Dyna PAS 3. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | Low-cost hybrid line stage using a computer-optimized 12AT7A gain stage and integrated circuit buffer output. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | 12AT7A-based premium hybrid line stage using a computer-optimized 12AT7A gain stage and optimized power-MOSFET buffer output stage. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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c. 2002 | c. 2002 | ||
- | **Contribution: | + | All-tube buffered line stage using a computer-optimized 12AT7A gain stage and 12AU7 buffer stage. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | All-new power high-voltage supply regulation circuits for use with all AVA tube and hybrid products. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | Remote controlled volume circuit adaptable to all existing AVA preamplifiers. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | Revision of AVA’s low-power tube amplifier circuits for the Dyna ST70 chassis. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | Next-generation S/PDIF decoder and DAC board |
- | **Discussion:** In the mid-1990s, I built AVA a prototype stand-alone DAC that demonstrated to them that producing such a product was within their manufacturing abilities. This ushered in an era of their being able to offer a product that they had previously considered impossible. So it was probably natural that they approached me to design the core circuits that would be used in their next generation of stand-alone DACs. They had preselected the the Wolfson WM8740 as the DAC IC they wanted the design based around, but by the time the design was completed we had moved to the WM8742. | + | **Contribution:** Design and implementation. |
- | AVA originally wanted to support only 44.1kHz PCM formats and a single coaxial S/PDIF input. Additionally, | + | **Discussion: |
+ | |||
+ | AVA originally wanted to support only 44.1kHz PCM formats and a single coaxial S/PDIF input. Additionally, | ||
This would be the first time AVA would use predominantly SMD parts in a PCB design. The previous generation DAC had used a single hand-soldered SOIC package. This design used SMD components exclusively. | This would be the first time AVA would use predominantly SMD parts in a PCB design. The previous generation DAC had used a single hand-soldered SOIC package. This design used SMD components exclusively. | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | All-tube, next-generation premium preamp line stage. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | Component value selection for best RIAA conformance. |
- | **Discussion: | + | **Contribution: |
+ | |||
+ | **Discussion: | ||
===== Vision DAC improved ===== | ===== Vision DAC improved ===== | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | New reconstruction and output stage based on a discrete, class-A, solid-state gain stage I developed as an independent project. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | New line stage based on a discrete, class-A, solid-state gain stage I developed as an independent project. |
+ | |||
+ | **Contribution: | ||
**Discussion: | **Discussion: | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | All-new DAC product with USB and S/PDIF inputs supporting high-rate PCM and DSD formats. |
+ | |||
+ | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
Working with application engineers at AKM, I developed support circuitry for the AK4490EQ whose low-frequency reference voltage stability was significantly greater than the circuits used in AK4490EQ reference designs. This in turn reduced the low frequency nonlinearity of the DAC appreciably over more conventional approaches. | Working with application engineers at AKM, I developed support circuitry for the AK4490EQ whose low-frequency reference voltage stability was significantly greater than the circuits used in AK4490EQ reference designs. This in turn reduced the low frequency nonlinearity of the DAC appreciably over more conventional approaches. | ||
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[[https:// | [[https:// | ||
- | **Contribution: | + | Fully remote-controllable chassis and supporting circuitry. |
- | **Discussion: | + | **Contribution: |
+ | |||
+ | **Discussion: | ||
===== RB-RC ===== | ===== RB-RC ===== | ||
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c. 2018 | c. 2018 | ||
- | **Contribution: | + | Low-cost remote controlled volume circuit adaptable to AVA' |
- | **Discussion:** Given the availability of a less costly remote control transmitter that I secured for the SLR and CFR chassis as well as AVA's newly founded ability to burn microcontrollers in house, it was natural to apply these toward a stripped-down remote control design for their RB (Real Basic) preamplifer chassis to replace the previous volume-only remote control first developed 14 years earlier. Again I expected AVA to adopt the remote control as standard equipment on the RB chassis, and again they decided to offer it as an option, albeit not as costly as the solution it replaced. | + | **Contribution:** Concept origination, development, and implementation. |
- | ===== The future ===== | + | **Discussion: |
- | I continue to provide consulting services to Audio by Van Alstine, particularly in the areas of digital audio, small-signal analog audio, low-power amplifier design, and user interface design. | + | ===== The present ===== |
+ | |||
+ | I continue to provide | ||
+ | |||
+ | ===== The future ===== | ||
+ | Within audio, my work focuses on developing solutions that represent true audio progress rather than chasing coloration signatures that happen to be fashionable. On a more general level, my design interests include a desire to bring greater equity to technological realms and to improve user experiences in every stage of product use. I try to bring all this to bear as much as possible in my work for AVA. | ||
audio/audio_by_van_alstine_work.txt · Last modified: 2023/01/02 21:54 by mithat