Hello everyone,
I’ve just purchased an Arylic A100 amplifier-DAC on behalf of a friend, and I must say—it’s quite a remarkable little device. It drives both my DTQWTs and a pair of Harbeth M40.3s with ease.
Aside from the rather pointless FM tuner (poor reception) and a display that shows almost nothing, the unit works very well as a DAC over USB, RCA, and Toslink. It also connects as a streamer to an LMS server (with the uPnP plugin enabled) and even includes a phono input—pretty impressive for the price.
However, it lacks a headphone output, which is unfortunate, especially considering it has two seemingly useless microphone inputs—maybe for karaoke?
I’d like to add an external switch to connect a 32-ohm Beyerdynamic headphone, but since the TPA3255 chip uses a differential output, I can’t simply tie the grounds of the left and right channels together.
Some research suggests I’d need either two isolation transformers or a dedicated headphone amp chip.
I asked ChatGPT, and it suggests that a few resistors might be enough, based on the following schematic:
[TPA3255 Output L]----+----[ R1 ]----+----[ R2 ]----+-----> GND
| |
| +----> [L to headphone jack]
|
+----[C1]----> [L to headphone jack]
[TPA3255 Output R]----+----[ R1 ]----+----[ R2 ]----+-----> GND
| |
| +----> [R to headphone jack]
|
+----[C2]----> [R to headphone jack]
Any thoughts or experience with this? I’d love to hear from others who’ve tackled something similar.
Thanks in advance!
I’ve just purchased an Arylic A100 amplifier-DAC on behalf of a friend, and I must say—it’s quite a remarkable little device. It drives both my DTQWTs and a pair of Harbeth M40.3s with ease.
Aside from the rather pointless FM tuner (poor reception) and a display that shows almost nothing, the unit works very well as a DAC over USB, RCA, and Toslink. It also connects as a streamer to an LMS server (with the uPnP plugin enabled) and even includes a phono input—pretty impressive for the price.
However, it lacks a headphone output, which is unfortunate, especially considering it has two seemingly useless microphone inputs—maybe for karaoke?
I’d like to add an external switch to connect a 32-ohm Beyerdynamic headphone, but since the TPA3255 chip uses a differential output, I can’t simply tie the grounds of the left and right channels together.
Some research suggests I’d need either two isolation transformers or a dedicated headphone amp chip.
I asked ChatGPT, and it suggests that a few resistors might be enough, based on the following schematic:
[TPA3255 Output L]----+----[ R1 ]----+----[ R2 ]----+-----> GND
| |
| +----> [L to headphone jack]
|
+----[C1]----> [L to headphone jack]
[TPA3255 Output R]----+----[ R1 ]----+----[ R2 ]----+-----> GND
| |
| +----> [R to headphone jack]
|
+----[C2]----> [R to headphone jack]
Component Values (for Line-Level Output to Headphones)
- R1 = 1kΩ
- R2 = 100Ω to 300Ω (experiment based on headphone impedance)
- C1, C2 = 470uF (non-polar, or use two polarized in series with opposite polarity)
- These values reduce power and remove DC, allowing headphone-safe signals.
- All resistors 1W
Any thoughts or experience with this? I’d love to hear from others who’ve tackled something similar.
Thanks in advance!