Re: [EE] DAC-to-headphone-level output amp
Neil <[email protected]>
| Newsgroups | gmane.comp.hardware.microcontrollers.pic |
|---|---|
| Message-ID | <[email protected]> |
Gotcha. Thanks On 12/19/2024 7:18 PM, Dwayne Reid wrote: > Hi there, Neil. > > "AUX" level is usually -10dBV. That level is fairly close to what > headphones are happy with. > > dwayne > > > At 03:58 PM 12/19/2024, Neil wrote: >> I'm designing a one-off device for myself that will generate audio >> from a microcontroller and I want to send that audio to a small BLE >> audio transmitter (something I picked up on Amazon). >> The BLE transmitter has a 3.5mm headphone plug and they specify it's >> for "Aux" level devices, but works very well when plugged into my PC >> or cellphone, so I take that to mean headphone level. >> FWIW, the audio signal is mono, but I want to drive both left and >> right channels. >> >> Researching online gets me a whole lot of different answers -- >> everything from line level being 10k ohms input impedance and 1V or >> 2V to 3V and headphone level is 8 to 600 ohms, with voltage level >> from 0.3 to 0.8V (though I would've expected headphone level to be >> higher since it's amplified). >> >> Can anyone shed some light on this please. I'm unsure what I'd be >> designing for... should I just do an op-amp with a very low output >> impedance and adjustable volume until it sounds decent? Or is there a >> spec I should follow? >> Alternately, I'd be happy if there's some simple monolithic chip that >> would do this for me (take a 0V-3.3V audio signal from a uC DAC and >> convert it to headphone level audio). >> >> Cheers, >> -Neil. > > -- http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at https://mailman.mit.edu/mailman/listinfo/piclist