ECHO Pro guide

The Steam edition recognizes ECHO Pro DLC owned by your Steam account. See the ECHO Steam store page for product information.

Pro in Community

Community is completely free forever, with permanent updates. All ECHO Pro features and future Community updates are free, without purchase, sponsorship or compiling it yourself. This does not grant ownership of the Steam app or DLC; Steam still checks account ownership.

Older installers may retain earlier entitlement checks, and Community DSP has known implementation issues. Check your build, release notes and actual signal path. See the edition comparison.

Use Pro on Steam

1. Sign into the Steam account that owns ECHO Pro DLC.
2. Open ECHO properties in your Steam library and check that ECHO Pro DLC is enabled in the DLC list.
3. Launch ECHO from Steam and check your Pro status.
4. If the status has not refreshed, exit ECHO, make sure Steam is online, and relaunch.

No order number, QQ number or machine code is required. See Using the Steam edition.

PCM and SDM for Pro users

• ECHO PCM / SRC upsampling applies high-quality sample-rate conversion after decoding. It follows the 44.1 kHz and 48 kHz rate families and exposes multiplier, filter, quality, and CPU / CUDA choices. The result remains PCM.
• ECHO SDM / PCM-to-DSD oversamples and filters PCM, then uses sigma-delta modulation and noise shaping to generate 1-bit DSD / SDM. It is not native DSD passthrough or ordinary PCM upsampling, and it requires a compatible DAC, driver, and enough real-time compute.

Higher rates are not automatically better. Start SDM at a lower DSD rate, stay within the DAC’s documented capabilities, and return to PCM immediately if you hear noise or dropouts, get silence, or cannot open the device.

If Pro is not recognized

Check the signed-in account and whether the DLC is enabled. Include your ECHO version, operating system, Pro status and error message when reporting a problem.

Steam DLC does not become a Community license; Community’s currently opened features need no DLC. For older installers or historical standalone credentials, contact support without publishing credentials.