audio:audio_by_van_alstine_work
Differences
This shows you the differences between two versions of the page.
Both sides previous revisionPrevious revisionNext revision | Previous revisionNext revisionBoth sides next revision | ||
audio:audio_by_van_alstine_work [2019/08/02 21:35] – [Audio by Van Alstine work] mithat | audio:audio_by_van_alstine_work [2023/01/02 21:39] – [DVA Digital Preamplifier] mithat | ||
---|---|---|---|
Line 11: | Line 11: | ||
New vacuum tube line stage to replace AVA’s existing design originally derived from the Dyna PAS 3. | New vacuum tube line stage to replace AVA’s existing design originally derived from the Dyna PAS 3. | ||
- | **Contribution: | + | **Contribution: |
- | **Discussion: | + | **Discussion: |
===== Transcendence Six ===== | ===== Transcendence Six ===== | ||
Line 19: | Line 19: | ||
[[https:// | [[https:// | ||
- | Low-cost hybrid line stage using a computer-optimized 12AT7A gain stage and integrated circuit | + | Low-cost hybrid line stage using a computer-optimized 12AT7A gain stage and IC buffer output |
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
===== Transcendence Seven ===== | ===== Transcendence Seven ===== | ||
Line 33: | Line 33: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
===== "T7 CF" ===== | ===== "T7 CF" ===== | ||
Line 43: | Line 43: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
- | At the time I wasn’t given the go-ahead to prototype and test this design. My understanding is the AVA wanted to maintain a commitment to their patented architecture as they felt this gave them marketing distinction. However, this circuit | + | At the time I wasn’t given the go-ahead to prototype and test this design. My understanding is that AVA wanted to maintain a commitment to their patented |
===== Active power supplies for tube and hybrid electronics ===== | ===== Active power supplies for tube and hybrid electronics ===== | ||
Line 55: | Line 55: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
- | The Ultra preamplifier ([[https:// | + | The Ultra preamplifier ([[https:// |
===== Remote control ===== | ===== Remote control ===== | ||
Line 67: | Line 67: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
- | My original | + | My expectation was that AVA would offer the remote as standard equipment on all “big body” preamplifiers. Instead it was offered as a relatively costly option, which they justified because the remote control transmitters were costly, which they were because of the small quantities they ordered them in, which was the case because remote control was offered only as an option. |
===== Ultimate 70 and Ultravalve power amplifiers ===== | ===== Ultimate 70 and Ultravalve power amplifiers ===== | ||
Line 79: | Line 79: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
===== DAC core for Vision and Vision Hybrid DACs ===== | ===== DAC core for Vision and Vision Hybrid DACs ===== | ||
Line 89: | Line 89: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
- | AVA originally wanted to support only 44.1kHz PCM formats | + | AVA originally wanted to support only 44.1kHz PCM formats |
- | 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 | + | 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 |
I was not involved in the development of the analog stages for the first DAC products using this board. However, I was responsible for the analog circuits found in the [[# | I was not involved in the development of the analog stages for the first DAC products using this board. However, I was responsible for the analog circuits found in the [[# | ||
Line 105: | Line 105: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
===== Vision RIAA Phono Preamplifer ===== | ===== Vision RIAA Phono Preamplifer ===== | ||
Line 115: | Line 115: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
===== Vision DAC improved ===== | ===== Vision DAC improved ===== | ||
Line 131: | Line 131: | ||
[[https:// | [[https:// | ||
- | New line stage based on a discrete, class-A, solid-state gain stage I developed as an independent project. | + | New line stage based on a discrete, class-A, solid-state gain stage (developed as an independent project). |
**Contribution: | **Contribution: | ||
Line 149: | Line 149: | ||
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. | ||
- | This would be the first design that required AVA to use microcontrollers they would burn in-house | + | This would be the first design that required AVA to use microcontrollers they would burn in-house, and it did so in a big way. I ended up using three independent microcontrollers in the final product, one for each of the DAC’s core functions: input selection and control, DAC control, and the user interface. Also notable in this design is the scale to which SMD technology was adopted and the high level of build integration. These required introducing significant changes to AVA’s manufacturing workflow, which in turn brought AVA’s production methods more in line with modern approaches. |
===== Vision SLR, Fet Valve CFR ===== | ===== Vision SLR, Fet Valve CFR ===== | ||
Line 157: | Line 157: | ||
Fully remote-controllable chassis and supporting circuitry. | Fully remote-controllable chassis and supporting circuitry. | ||
- | **Contribution: | + | **Contribution: |
**Discussion: | **Discussion: | ||
Line 169: | Line 169: | ||
**Contribution: | **Contribution: | ||
- | **Discussion: | + | **Discussion: |
+ | |||
+ | ===== RC3 ===== | ||
+ | c. 2020--2021 | ||
+ | |||
+ | Embedded design for IR remote control sending with silicone membrane switches. | ||
+ | |||
+ | **Contribution: | ||
+ | |||
+ | **Discussion: | ||
+ | |||
+ | ===== DVA Digital Preamplifier ===== | ||
+ | c. 2018--2021 | ||
+ | |||
+ | **Contribution: | ||
+ | |||
+ | **Discussion: | ||
+ | |||
+ | The DVA Digital Preamplifier also brought forth a new design aesthetic and chassis mechanics that I originally intended as a one-off transitional one. As is often the case, it took a good amount of work to convince AVA of the merits of making the change. But once the design was released, it received, for the first time ever for an AVA product, praise in the audiophile press for its aesthetics. Likely as a result of this, AVA asked me to design or redesign faceplates for a variety of new and existing products. | ||
+ | |||
+ | What this means is that my original plan of transitioning to a brand new design program that takes updated user, business, and manufacturing requirements into full consideration will be delayed. I regard this as an odd manifestation of [[https:// | ||
+ | ===== DVA A2D ===== | ||
+ | c. 2021 | ||
+ | |||
+ | **Contribution: | ||
+ | |||
+ | **Discussion: | ||
+ | |||
+ | ===== DVA R2X ===== | ||
+ | c. 2021 | ||
+ | |||
+ | **Contribution: | ||
+ | |||
+ | **Discussion: | ||
+ | ===== The present ===== | ||
+ | |||
+ | I continue to provide consulting services to Audio by Van Alstine, particularly in the areas of digital audio, small-signal analog audio, circuit simulation, and user interface design. For reasons that should be obvious, I'm not at liberty to discuss projects under development. | ||
===== The future ===== | ===== The future ===== | ||
- | 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. | + | Within audio, my work focuses on developing solutions that represent |
audio/audio_by_van_alstine_work.txt · Last modified: 2023/01/02 21:54 by mithat