The Fosi Audio GR40 combines an ESS ES9028Q2M DAC, a two-tube preamp stage and a 3.5mm headphone amp, with Bluetooth 5.1 (aptX HD, aptX LL), USB, optical and coaxial inputs. It suits desktop setups that feed powered speakers or a power amp, with headphones on the side.
Who the Fosi Audio GR40 is for
Powered speakers on a desk: The RCA output feeds powered speakers, or a power amp for passive speakers, from Bluetooth, USB, optical or coaxial sources.
Headphone listening: The 3.5mm jack is rated 250mW @ 32Ω, and the RCA output mutes while headphones are plugged in.
Hi-res files from a computer: Over USB, the ES9028Q2M DAC decodes PCM up to 32-bit/384kHz and DSD256.
Wireless streaming: A Qualcomm QCC3031 Bluetooth 5.1 module supports SBC, AAC, aptX, aptX HD and aptX LL.
Tube rolling: The two tubes are user-replaceable; Fosi lists EF95, 6AK5, 6J1 and similar types as compatible.
Skip it if: You need an analog input or balanced outputs; the GR40 has no RCA input and outputs on RCA and 3.5mm only.
Tubes: 2 × 5654W, user-replaceable (Fosi notes the tube type may vary by batch)
Power: 12V DC adapter included
In the box: GR40, 2 vacuum tubes, 2 decorative rings, Bluetooth antenna, power adapter, user manual
Genuine Fosi Audio stock. Free shipping on every order, 45-day returns.
Fosi Audio GR40 vs similar options
vs Fosi Audio GR70: Adds a Class A OTL design with four tubes, 6.35mm and 3.5mm jacks and up to 300mW @ 32Ω, but takes RCA input only; pick the GR40 for its built-in ES9028Q2M DAC and Bluetooth aptX HD.
vs Fosi Audio SK02: Adds an ES9038Q2M DAC, a 4.4mm balanced output and up to 755mW at 32 ohms over USB-C; pick the GR40 for tubes, Bluetooth aptX HD, and optical and coaxial inputs.
Yes. Every unit we sell is genuine and brand-new, shipped in its original packaging, and backed by our 1-year TonePier warranty and 45-day returns.
Where does my order ship from, and how long does it take?
Every order ships from our warehouse in China, with full tracking, and most orders ship within 3 business days. Shipping is free on every order; most US orders arrive within 7–15 business days and most orders to other countries within 7–20 business days — see our shipping policy for details.
What if it isn't for me?
You get 45 days to decide. Keep the packaging, keep it in like-new condition, and send it back for a refund. Ear tips unsealed for hygiene reasons are fine — we expect you to actually listen.
Choosing a selection results in a full page refresh.
