On Wed, 30 Apr 2014, chris hermansen wrote: > > Clemens and list, > > On Apr 30, 2014 12:07 AM, "Clemens Ladisch" <cladisch@xxxxxxxxxxxxxx> wrote: > > > > Bill Unruh wrote: > > >> On 29/04/14 15:52, Balduin Waldmeister wrote: > > >>> So my question is whether it's possible to add the low impedance support > > >>> (16 - 32 ohm) to ALSA for use with the old STX? Currently it stops at > > >>> the normal gain setting (< 64 ohm). > > > > > > That has to do with the capabilities of the amplifier on board the sound card, > > > not the settings of the card. The amplifier needs to be able to deliver high > > > current and have a low output impedence-- ie it is a hardware issue. > > > Not at all sure what the impdence settings on the card would do. > > > > The "impedance" setting just lowers the volume. (<300 ? and <64 ? are > > -6 dB and -18 dB.) I didn't think this was worth implementing in the > > Linux driver, but people whined until I did. > > > > It is certainly possible to add a fourth setting. In the advertising bunff from the company, they have graphs with horrendously unequal frequency response ( a huge bump in the middle of the spectrum) and they say that the impedance setting boost bass and treble more than mids to equalize it. Now that could be just marketing having no idea, or it could mean that the designers designed a horrendous output stage with large capacitive and inductive loadings so that into low impedances, they took over and produced very bad frequency response, and those setting stuck in compensatory bass and treble boosts. But you might also be right that this is all marketing. > > > > Being charitable, this might not be a HiFi Voodoo stunt by Asus > > marketing, but an honest attempt at preventing unhealthily loud > > output levels ... Or to prevent distortion since the low impedance may demand too much current for the drivers at higher amplitudes. > > As someone who has benefitted from your incredible support over (at least) the last few years... > > Wow. I sit at your feet master to benefit from your teachings on being charitable. Evidently I have a great deal more to learn on > this matter (to say the least). > > > ------------------------------------------------------------------------------ "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE Instantly run your Selenium tests across 300+ browser/OS combos. Get unparalleled scalability from the best Selenium testing platform available. Simple to use. Nothing to install. Get started now for free." http://p.sf.net/sfu/SauceLabs _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
