What am I missing? I use 600-ohm stereo headphones plugged directly into the front panel jack of my K3S.
I run the Audio Gain control at 9 o’clock — roughly a 25% rotation toward full volume. I have more than enough audio for my elderly ears, and when I pull the headphone plug out of the jack, my speaker audio is at a comparable level. What is the non-problem with high-impedance phones that you guys are trying to solve? Bud, W2RU > On Dec 28, 2015, at 1:59 09PM, Steve Ellington <steven...@gmail.com> wrote: > > K3 uses the. > > LM4811 Headphone Amplifier > > Texas Instruments Specs for output Z > > RL = 16Ω 105 mW > RL = 32Ω 70 mW > > At 60 ohms the output power drops to 20 mw. Per their graphs. > > 300 ohms is not even considered. > > Amplifier gain control is done digitally within the chip. With such a high > Z load, gain would likely need increasing. > The results of doing so are unknown. Consider pop, click, white noise etc. > > Also consider what happens when switching from headphones to speaker when > the AF Gain control is turned up high. Blasting? > > I suggest sticking within the 16 to 32 ohm range. > > Steve N4LQ > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
