Originally Posted by
CDWMcInSpots /img/forum/go_quote.gif
Fostex HP-A8C
Fostex has published the following headphone output specifications for the Fostex HP-A8C:
Quote:
http://www.fostexinternational.com/docs/products/HP-A8C.shtml#3
Specifications
Output
Phones 1,2 Connector: Stereo phone
Max Output: 700mW (32-ohm loaded)
Opt load Impedance: 16 ohm – 600 ohm
THD: less than 0.002% at 1kHz, 32-ohm loaded, 100mW
Frequency response: 10Hz - 80kHz +-0.3dB
Does anyone know the headphone output:
- Impedance?
- Power in different impedance loads, typically from 16/25 to 600 ohms?
Windows driver for USB Audio Class 2.0 coexistence
Windows needs a driver to support USB Audio Class 2.0 devices. Many manufacturers base their Windows drivers and firmware on software from
Thesycon Systemsoftware & Consulting GmbH. The Thesycon software is, according to Thesycon, supposed to be customized by the hardware manufacturer to their products. Some manufacturers do it themselves, and others (like Grace Design) use external companies like
Wavelength Audio and their Gordon Rankin. Some companies do a good customization job, others are sloppy and don't fullfill their contractual obligations with and according to Thesycon.
According to Thesycon, products that use software based on Thesycon's products should be able to coexist on a computer. Unfortunately that isn't necessarily the case because of sloppy software customization by hardware manufacturers. Some can coeeist, others won't. The user will then be forced to uninstall, install and configure drivers whenever he wants to change between USB DACs.
As far as I've understood,
Wavelength Audio and their Gordon Rankin make sure that all products using their (Thesycon based) software can coexist.
I have experienced a product that use Thesycon based software but its Thesycon driver wouldn't coexist with one using software from
Wavelength Audio/Gordon Rankin. The manufacturer didn't reply to e-mails, and hasn't corrected the problem within a period of more than 6 months after the importer was informed and subsequently informed the manufacturer. The other manufacturers and parties involved (including Thesycon which was very quick, thorough and to the point) answered e-mails quickly or within a reasonable period. I don't want to experience the same again.
Why is coexistence important? One might want to have two different USB DACs in two different locations, for example two rooms or floors in ones home, home and work, home and
cottage, etc., and on a regular basis carry one portable computer between the locations and use it alternately with both DACs.
Fostex HP-A8C Windows driver for USB Audio Class 2.0
Questions:
- Does Fostex HP-A8C use firmware and drivers based on products from Thesycon?
- Does Fostex HP-A8C identify itself as "Fostex HP-A8C" or something similar in the USB driver and Windows sound control panel, or does it identify itself as something more generic like "USB DAC"? The latter may indicate sloppy software customization as with my device mentioned above.
- Will the Fostex HP-A8C Windows driver for USB Audio Class 2.0 coexist with other manufacturers Windows drivers for USB Audio Class 2.0 on the same computer?
- Will the Fostex HP-A8C Windows driver for USB Audio Class 2.0 coexist on the same computer with Windows drivers for USB Audio Class 2.0 made by Wavelength Audio/Gordon Rankin?