Audio cables, linear power supplies and adapters, op-amps, vacuum tubes, stands, speaker spikes and other audio accessories.
Douk Audio 7.83Hz Schumann Wave Generator — read reviewA plug-in device that emits a 7.83Hz Schumann resonance signal into a room. Douk Audio positions it for relaxation, sleep and listening-room ambience, and notes it makes no sound of its own.
Burson Audio V7 Discrete Dual Op Amp (1 Pair) — read reviewA fully discrete dual op-amp pair in DIP8 form, offered in Vivid or Classic voicings, with multi-layer PCB signal isolation and an aluminum shell that doubles as a heatsink.
Douk Audio D2-PRO 35W Linear Power Supply — read reviewA 35W linear power supply with 28uV ripple, dual DC 12V outputs and 2.5A capacity for DACs, preamps, streamers and other noise-sensitive 12V audio gear.
Ampapa BK1 Aluminum Stand for A1/D1/Q1 — read reviewA modular all-aluminum desktop stand for Ampapa A1, Q1 and D1 gear, with ventilated tiers for passive cooling and flexible 3-layer or expanded 2-layer stacking.
Douk Audio CT1-BOX Bias Current Probe Tester — read reviewA pair of ceramic-socket bias probes plus a dual-meter box for reading power tube cathode current on EL34, KT88, 6L6, 6V6, 6550, KT66 and similar tubes.
Douk Audio D2 15W Linear Power Supply — read reviewA 15W linear power supply with sub-20uV ripple, one DC and one USB-A 5V output, and a sealed transformer plus LM1085IT regulator for noise-sensitive 5V audio devices.
Douk Audio DC Power Supply Adapter — read reviewA regulated DC power adapter family for Douk Audio and Nobsound amplifiers, with 19V to 48V versions rated up to 10A, universal AC 100-240V input and full protection circuitry.
Douk Audio 14AWG OFC Speaker Cable — read reviewA pre-terminated 14AWG speaker cable with gold-plated pure copper banana plugs at both ends, built from tin-plated 4N oxygen-free copper under a braided PVC jacket. Sold as a single run.
Douk Audio 3.5mm Male to Male AUX Cable — read reviewA shielded 3.5mm-to-3.5mm stereo AUX cable using 99.99% copper wire, gold-plated connectors and Oyaide silver-bearing soldering, available in lengths from 0.75m to 5m for car or home use.
GE 7-Pin JAN 5654W Vacuum Tubes (Matched Pair) — read reviewA tested and matched pair of low-noise, US-made GE JAN 5654W 7-pin tubes — mil-spec stock that drops into 6AK5, 6J1, 6J1P and EF95 sockets as a premium upgrade.
Sparkos Labs SS3602 Discrete Dual Op Amp (1PC) — read reviewA true dual discrete op-amp in a DIP8-compatible package with a Class A biased output stage, 140dB open-loop gain and gold-plated pins for upgrading IC op-amps.
E1DA APU Cosmos Analog Unit Kit — read reviewA single-channel analog processing unit with a notch section and a low-noise preamp, sold here as a $109 assembly kit with an uncalibrated board. The page frames it for measuring DAC and amplifier distortion, ripping vinyl and condenser mics.
Fanmusic C006 XLR Balanced Cable — read reviewAn XLR female-to-male cable listed at $69.99 for 20cm and $79.99 for 50cm. The page names NEUTRIK NC3MXX-B and NC3FXX-B connectors and a CANARE two-core line, so it suits buyers who want named connector parts and a conductor breakdown in the page text.
Ampapa 6.35mm TRS Balanced Audio Cable — read reviewA 1m balanced 6.35mm TRS to TRS cable pair with 6N oxygen-free copper conductors, gold-plated plugs, carbon fiber shells and tinned copper braided shielding.
Ampapa 1/4-Inch TRS to XLR Female Cable — read reviewA balanced 6.35mm TRS-to-XLR female interconnect sold as a pair, using 40-strand 6N oxygen-free copper, tinned copper braided shielding and carbon fiber-metal composite plugs. 1 m / 3 ft each.
Douk Audio 3.5mm to RCA Stereo Cable — read reviewA bidirectional 3.5mm-to-twin-RCA stereo cable that bridges phones, tablets and PCs with preamps, amps and DACs, using 6N oxygen-free copper, gold-plated plugs and a braided shield. 1 m / 3 ft.
Douk Audio Dual RCA to RCA Stereo Cable — read reviewA directional twin-RCA analog interconnect built with 6N oxygen-free copper, tinned copper braided shielding and 24K gold-plated plugs — a simple quality step up for amps, DACs and CD players. 1 m / 3 ft.
Nobsound Aluminum Spring Speaker Spikes — read reviewSpring-based isolation feet for speakers, amps and CD players: CNC-machined aluminum alloy bodies with tunable springs and anti-skid rubber, damping vibration up to a 50kg load.
E1DA Cosmos Scaler Variable Gain Pre-Amp — read reviewA variable gain buffer that the page's specification section says is made for the Cosmos ADC, listed at $129 as a pre-amp. It lists 16 gain values from 0 to 26.078db and an Auto position, and it suits Cosmos ADC owners more than buyers who want a headphone amp with a stated output power.
TOPPING TCT1 6.35mm TRS Balanced Cable — read reviewA TOPPING balanced cable from 6.35mm TRS to 6.35mm TRS, listed from $49 in 25CM and 75CM options and a pair per the store title. The page text gives wire core counts, a conductor resistance and an 8MM OD, though the resistance is printed two ways.
TOPPING TCT2 XLR to 6.35mm TRS Cable — read reviewA TOPPING balanced cable from a 3-pin male XLR to a 6.35mm TRS, a pair per the store title, with a 75CM option at $67.15 and a 125CM option sold out when the page was read. The page text lists core counts, a resistance printed two ways and an 8MM OD. It suits buyers who need that XLR to TRS run.
TOPPING TCT3 TRS to XLR Balanced Cable — read reviewListed as a balanced copper cable with a 6.35mm TRS plug at one end and a 3-pin female XLR at the other, titled as a pair, from $69 in 25CM and 125CM options. The page text lists 6N single crystal copper wire and an 8MM OD, so it suits buyers who need that connector pairing.
SKW BG-05 Speaker Cable — read reviewA speaker cable listed from $69, with a 6N Single Crystal Copper conductor in its specification section, banana tip and spade tip plugs in the packing list and lengths from 1m to 12m. It suits buyers who have already picked a length and a 1 pc or 1 pair size.
SKW BG-04 2 RCA Male-to-Male Cable — read reviewA male-to-male cable with RCA at both ends, listed from $25.99 in ten lengths from 0.25m to 15m. The page text gives a 7.0mm outer diameter, a gold plated plug and a '6N single crystal copper' materials line, and it names speaker, amplifier and DVD player among its applications.
This guide covers the 18 reviews from Douk Audio's store at doukaudio.com (accessories sold by HiFiGO, added on October 28, 2026, have their own reviews on this page), and they cover very different things: seven cables, three power supplies (the D2 and D2-PRO linear supplies and a family of DC adapters), two discrete op-amps, a matched pair of tubes, a stand, speaker spikes, a bias probe, a Schumann wave generator and a gift card. Prices run from $11.00 to $199.99 as priced on October 23, 2026, so decide first what the part has to match. For a cable that means connector type and gender: the listings include 6.35mm TRS, TRS to XLR female, 3.5mm to RCA, RCA to RCA, 3.5mm to 3.5mm and banana-plug speaker cables. Four of the seven list only a 1 m (3 ft) length, and quantity differs: three are sold as pairs, while the 3.5mm-to-RCA, RCA-to-RCA and 14AWG speaker cables ship one per order (the 14AWG listing says one cable serves one speaker) and the AUX listing states no quantity.
Cable listings name conductors and plating (four list 6N oxygen-free copper, one 4N, one oxygen-free copper without a grade, one 99.99% copper), but the reviews note that none publishes a capacitance or LCR measurement, so those claims rest on the store's description. For power, voltage and plug come first. The D2 is fixed at 5V (15W, 2.5A shared by its USB-A and DC outputs), the D2-PRO at 12V (up to 35W with 2.5A across two outputs), and the DC adapter family spans 19V to 48V with a 5.5x2.5mm centre-positive plug. Ripple, the leftover AC noise on a DC output, is quoted as below 20uV for the D2 and 28uV RMS for the D2-PRO, both under no-load conditions. Op-amps and tubes are swap-in parts: the Burson V7 stands 20mm tall, the Sparkos SS3602 about 10.5mm above the board, and the GE 5654W tubes fit only 7-pin 6J1, 6J1P, 6J1P-EB, 6Zh1P-EV, 6AK5, 6AK5W and EF95 sockets.
Douk Audio's store applies the same terms to all of its listings. Its shipping page lists 2-8 business days, with duties, taxes and customs fees included in the checkout price unless noted. Returns must be requested within 30 days of delivery and approved by Douk before the item goes back, within 7 days of approval; original shipping fees and duties aren't refunded, and the reviews do not say who pays the return shipping. The warranty is 24 months from purchase for manufacturing defects; an older policy page still says 1 year. The two op-amp listings add that damage from incorrect installation, such as wrong orientation, is not covered by warranty or compensation. The gift card is valid only for purchases at doukaudio.com; its page lists values of $100, $300, $500 and $1,000 against a displayed price of $95.00 and states no delivery details or expiry date. HiFiGO, the other store on this page, ships from China, gives 7 days to report a faulty item and charges a 30% restocking fee on later returns; each HiFiGO review spells out its terms.
Look elsewhere, or ask the store first, in a few cases. The Ampapa BK1 stand ($79.99) is sized for Ampapa A1, D1 and Q1 components, publishes no weight rating or tier dimensions, and may not line up with other brands. The spring speaker spikes ($35.99) list a 50kg load per set and a height of 38mm, and their title says 4PCS while the packing list counts 8 pads. The Schumann wave generator ($52.99) makes no sound, and Douk Audio says it does not improve sound or video quality directly. The CT1-BOX bias probe ($56.99) only measures, and covers just the listed octal power tubes.
It depends on the listing. The 6.35mm TRS cable ($32.99), the TRS-to-XLR cable ($36.99) and the banana-plug speaker cable ($39.99) are sold as pairs. The 3.5mm-to-RCA ($26.99), RCA-to-RCA ($29.99) and 14AWG speaker ($27.99) cables ship one per order, and the 14AWG page says each cable handles a single speaker, so a stereo pair needs two. The $11.00 AUX page does not state a quantity.
Match the voltage and current your device states. The D2 is fixed at 5V and the D2-PRO at 12V. The DC adapter listing offers 19V/4.74A, 24V/4.5A, 24V/6A, 32V/5A, 36V/5A, 48V/5A and a 48V/10A option, all with a 5.5x2.5mm plug, inside positive. The D2-PRO page does not state its plug size or which cables ship, so confirm that with the store.
The listings cannot settle it. Among the Douk Audio store's cables, four list 6N oxygen-free copper, one 4N, one oxygen-free copper without a grade and one 99.99% copper, at $11.00 to $39.99, and none publishes capacitance or LCR figures, so the material and shielding claims rest on the store's description. Check connector type, gender and length before material.
The D2 listing aims at DACs, DDCs, Raspberry Pi, USB audio devices and headphone amps; the D2-PRO at 12V DACs, preamps, headphone amps, streamers and switches. Its review adds that, as with any linear supply, the audible gains are concentrated on gear that is sensitive to switching-adapter noise rather than every connected device. Douk also says ground noise can appear when the D2 powers two devices at once.
The Burson V7 and Sparkos SS3602 listings say damage from incorrect installation, such as wrong orientation, is not covered by warranty or compensation. The SS3602 listing says to disconnect power and align the op-amp notch with the socket notch; the V7 listing says to power off and allow a 5-10 minute cool-down, since it runs at 60-70 degrees C by design. Check clearance too: the V7 is 20mm tall.
Douk Audio's store allows a return request within 30 days of delivery. Douk must approve it first, the item goes back within 7 days of approval, and original shipping fees and duties aren't refunded. The warranty is 24 months from purchase for manufacturing defects, with free repair or replacement, although an older policy page still says 1 year. HiFiGO's terms differ (7 days for faulty items, a 30% restocking fee on later returns) and are in each HiFiGO review.