Questyle

Questyle Sigma Pro Bluetooth 5.4 Headphone Amplifier USB DAC AMP with LDAC | MFi Certified Portable DAC with aptX Lossless,PCM768/DSD512 6.35mm/4.4mm/3.5mm Output for Smartphones/PC/ Home Audio(Sliver)

Name: Questyle Sigma Pro Bluetooth 5.4 Headphone Amplifier USB DAC AMP with LDAC | MFi Certified Portable DAC with aptX Lossless,PCM768/DSD512
Brand: Questyle
SKU: B0G112FLRH
Price: 899.00 USD
Availability: InStock

By Mike Perry, Hardware Editor · Verified 2026-09-22

Mike Perry has researched PC hardware since 2014, tracking 80+ GPU generations, 50+ retro handheld platforms, and 30+ vintage PC configurations. He synthesises community benchmarks, manufacturer specs, and public forum data into actionable buying guides. View full credentials →

$899.00

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🛒 See live eBay price Also on Amazon — View Current Price → Compare to similar audio & midi

*Price sourced from Amazon.com. Last updated 2026-08-15. Price and availability subject to change.

Bottom line: The Questyle Sigma Pro Bluetooth 5.4 Headphone Amplifier USB DAC AMP with LDAC | MFi Certified Portable DAC with aptX Lossless,PCM768/DSD512 6.35mm/4.4mm/3.5mm Output for Smartphones/PC/ Home Audio(Sliver) is a specs-and-price decision rather than a crowd-consensus one in the audio & midi category, priced around $899.00. Check the specification table above against one or two close alternatives — on price and spec fit, not on star ratings.

Pros & Cons

Pros

✓ Backed by Questyle's warranty and support channels
✓ Ships via Amazon with Prime eligibility and the standard returns policy

Cons

✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified

Small in size, big on performance. SIGMA Pro is our flagship portable DAC/amp, built on Questyle's pursuit of audio perfection. It is a technological benchmark that proves performance and portability can coexist, delivering a truly "Portable Professional audio equipment" experience.

SpecPicks Verdict

SpecPicks scored Questyle Sigma Pro Bluetooth 5.4 Headphone Amplifier USB DAC AMP… using a rating × review-volume × price-fit model applied to our editorial and benchmark analysis across the audio & midi category. Questyle's audio & midi lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.

Common buyer scenarios for audio & midi of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.

Key Features

[Powerful & Refined Sound]: SIGMA Pro delivers robust driving power and exquisite sonic detail through its patented, fully discrete current-mode amplifier, achieving exceptional audio performance and high efficiency in a pocket-sized form factor.The fully discrete Current Mode Amplifier delivers a peak power of 5W and a peak current of 3A, enabling formidable driving force. With a peak output voltage of up to 20Vp-p and load distortion as low as 0.0002%, it ensures both power and precision.
[Advanced Decoding Performance]: Utilizing dual ESS9069 DAC chips and a TTA decoding architecture, it provides high-end decoding performance surpassing typical portable devices, supporting PCM768 and DSD512 to meet the demands of top-tier sound quality.
[MFi Certification]: The SIGMA Pro has obtained MFi license. This certification ensures perfect support for iPhone/iPad and connectivity within the ecosystem, meeting stringent comprehensive requirements for power consumption and compatibility of external devices, while also avoiding the risk of damage to phones and systems from using uncertified USB accessories.
[Qualcomm Snapdragon Sound & LDAC Certified]: The SIGMA Pro incorporates the latest Qualcomm Snapdragon Sound technology, features Bluetooth version 5.4, and is fully certified by both Qualcomm Snapdragon Sound and LDAC. Snapdragon Sound utilizes leading Qualcomm aptX Adaptive technology and supports aptX HD lossless audio, delivering CD-quality 16-bit/44.1kHz lossless audio, 24-bit/48kHz, and 24-bit/96kHz high-resolution audio over Bluetooth.
[Extensive Connectivity & Compatibility]: Equipped with high-speed USB interfaces and lossless Bluetooth, the SIGMA Pro is compatible with iOS, HarmonyOS, Android 5.1+, Windows 10 (driver-free), and macOS. Meticulously optimized by the Questyle Lab, it ensures flawless compatibility with a wide range of devices, including smartphones, computers, and professional audio systems.
[Comprehensive Connectivity]: The SIGMA Pro is equipped with three headphone output jacks: 3.5mm, 4.4mm, and 6.35mm, paired with a manual gain adjustment function. Without complex operations, it allows you to easily switch between different working modes and personalized settings based on different headphones and listening scenarios, meeting diverse audio needs.

Full Specifications

Brand	Questyle
Connectivity	Bluetooth, USB
Model Number	SIGMA Pro
Compatibility	PC, Switch, Android, iOS, Mac
Built-In Media	Cable, User Manual
Mfr Part Number	SIGMA Pro
Number of Items	1
Warranty Description	12 Months

Ready to buy?

Questyle Sigma Pro Bluetooth 5.4 Headphone Amplifier USB DAC AMP with LDAC | MFi Certified Portable DAC with aptX Lossless,PCM768/DSD512 6.35mm/4.4mm/3.5mm Output for Smartphones/PC/ Home Audio(Sliver) is sold on the used and vintage market, where eBay carries the live inventory — Amazon does not stock this part. Prices and condition vary by seller and move in real time, so we link the live listing rather than quote a cached price. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

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*Price sourced from Amazon.com. Last updated 2026-08-15. Price and availability subject to change.