E1DA APU Cosmos Analog Unit Kit Review
A 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.
Our verdict
Suited to buyers who want a notch-and-preamp measurement tool, or a phono or microphone preamp stage, and are comfortable assembling a kit with an uncalibrated board at $109. Look elsewhere if you want a ready-assembled, calibrated unit or a conventional line preamp. The main caveat is that the figures are the page's own, with input limits the page says can damage the unit if exceeded.
- Best for
- Buyers who want a notch and preamp measurement tool and will assemble a kit with an uncalibrated board.
- Skip if
- You want a ready-assembled, calibrated unit or a conventional line preamp.
Why 3.6/5: A specification list with figures lifts it. The store's terms conflict with each other, which holds it back, and no independent test of this model was checked for this review.
The E1DA APU Cosmos is described on its page as a single-channel analog processing unit that combines a notch section with a low-noise preamp, and the $109 review price is for the Assembly Kit, whose board is not calibrated. The page lists input limits of 3.5Vrms for the preamp and 10Vrms for the notch, gains of 34/60db and 20db plus 0/6db, residual noise figures in nanovolts and 48V phantom power for condenser mics.
Specifications
| Spec | Page says |
|---|---|
| Purpose (page) | Single-channel THD+N and noise/DR measurement tool for the Cosmos ADC |
| Version priced here | Assembly Kit; Cosmos APU PCBA not calibrated |
| Dimensions | PCBA 90x50x29mm; 104x61x39mm (second size not labeled) |
| Weight | PCBA 34g; assembled unit 157g |
| Power | USB-C +5V rail, 350mA idle current |
| Inputs | 3.5mm jacks, TRRS pinout +In/-In/GND/GND |
| Outputs | 3.5mm jacks, TRRS pinout +Out/GND/GND/GND; unbalanced |
| Notch section | Balanced (FDA) up to 10Vrms; gain 20db + 0/6db (switchable) |
| Notch ratio | -30db at 1kHz or 10kHz (switchable) |
| Notch residual noise | 950nVrms(A) typical (gain 20+6db, Fnotch=1kHz) |
| Preamp section | Balanced (FDA) up to 3.5Vrms; gain 34/60db |
| Preamp residual noise | Under 130nVrms(A) at +60db gain; under 260nVrms(A) at +34db |
| Phantom power | 48VDC+/-4V, 2x6.8kOhm, for condenser mics |
| Preamp bandwidth | 10Hz-1MHz+ -3db@60db gain; 10Hz-5MHz+ -3db@34db gain |
Options and pricing
The only option is the Assembly Kit at $109, which showed as orderable when the page was read. The kit contents named are an uncalibrated Cosmos APU PCBA, a wooden box, case extrusion, front and rear panels, 4 black silicone legs, 4 M3 screws, 8 black screws and a red silicone protector for the phantom power. The page also describes a Black Housing Unit as assembled and calibrated and a PCBA-only version as not, but neither is listed as an option here.
How it compares
The page text of the APU read for this review describes measurement, vinyl-ripping and microphone uses rather than headphone or speaker listening. The E1DA 9038D6K USB Headphone Amp 3.5mm Jack Unbalanced Output DAC+HPA at $135 and the E1DA Susumu edition 9038SG3 USB DAC Headphone Amp from $93.99 are named as USB headphone amplifiers, against $109 here for an assembly kit. The TOPPING L30 Headphone Amp at $97.49 is a headphone amplifier by name. Choose the APU only if its measurement, phono or microphone uses are what you need.
Shipping, returns and warranty
HiFiGO sells from hifigo.com and says every order leaves its warehouse in China, usually 1-3 business days after it is placed, and says its delivery times are estimates, not promises. Its shipping policy gives the United States 1-2 weeks (about 10 days on average) by Priority and 6-10 days by Premium, both with duties and taxes prepaid by the store; Canada 2-3 weeks; the United Kingdom 1-2 weeks; and Australia 10-15 days. Express couriers (DHL, UPS, FedEx) take 3-7 days, but then the buyer pays any duties and taxes. No shipping page names New Zealand, PO boxes are not accepted, and the free-shipping thresholds differ between the store's own pages, so check the cart. One of its two shipping pages adds that a lost parcel on an order above $50 gets only a 50% refund. A US buyer reported a $40 tariff charge in August 2025, after which HiFiGO said it had added a customs notice at checkout.
Read the return terms before you order. The homepage advertises 7-day returns. Both of HiFiGO's policy pages offer a 7-day dead-on-arrival cover (a replacement or a full refund, with the return postage refunded) and also describe 30-day returns, but a request made 7 to 30 days after delivery loses 30% of the MSRP as a restocking fee (10% more if the packaging is incomplete), plus shipping both ways and duties, and the FAQ on the same pages says there is no refund or exchange once 7 days have passed. One version recommends reselling an opened product locally. Custom IEMs and custom cables cannot be returned, no return address is published, and buyers describe sending items back to China.
Cables and adapters get three months of warranty from the order date, against one year for DACs, amps and IEMs; a note on the same page also excludes cables from returns for hygiene reasons, while the FAQ says a cable can come back in its original condition. HiFiGO decides between repair and replacement and the buyer pays the shipping. Claims go to [email protected], the only contact the store lists: its pages name no company, street address or phone.
On Trustpilot, HiFiGO had 4.6 out of 5 from 378 reviews when we checked on 2026-10-28 (91% five-star, 5% one-star), and it had replied to about 75% of negative reviews; Trustpilot notes the store has not invited customers to review recently. The one-star reviews mostly concern the short return window and the deductions on returns, items listed in stock that turned out back-ordered, slow email support and a tariff charge on a US delivery in 2025. HiFiGO says its products are genuine and come in the brands' retail packaging; it does not claim to be an authorized dealer.
What we liked
- A specification list with input limits, gains, residual noise, distortion, size and weight
- Notch frequency switchable between 1kHz and 10kHz, and switchable gain on the notch section
- Internal 48VDC phantom power for condenser mics, with a red silicone protector in the kit
- The page says the preamp can serve as a phono preamp, with RIAA correction applied in a digital domain
- Size and weight are listed: PCBA 90x50x29mm and 34g; assembled unit 157g
Worth noting
- The kit's board is not calibrated; an assembled and calibrated Black Housing Unit is described but not listed as an option
- Input limits: the preamp takes up to 3.5Vrms and the notch up to 10Vrms, and the page says overvoltage may damage the unit
- The page asks buyers to be sure they understand what the device is before buying, and lists measurement, vinyl and microphone uses
- Needs a USB-C +5V source; the page recommends isolated power and suggests a charger or power bank over 600mA
Questions before you buy
What is in the $109 option?
The Assembly Kit: an uncalibrated Cosmos APU PCBA, a wooden box, case extrusion, front and rear panels, 4 black silicone legs, 4 M3 screws, 8 black screws and a red silicone protector for the phantom power. It is not the assembled and calibrated Black Housing Unit the page also describes.
What input voltages can it take?
Per the page, the Preamp inputs should stay at or below 3.5Vrms and the Notch inputs at or below 10Vrms. The page warns that overvoltage may damage the unit and that input resistors are usually the part that burns.
Does it have phantom power?
Yes. The Preamp inputs have internal 48VDC+/-4V phantom power through 2x6.8kOhm for condenser mics. The page says not to switch it on without a mic connected and to wait at least 10s after switching it off before plugging or unplugging anything.
Where does HiFiGO ship from, and how long does it take?
From its warehouse in China, usually 1-3 business days after the order. The shipping policy gives 1-2 weeks to the US by Priority (6-10 days by Premium), both with duties and taxes prepaid, 2-3 weeks to Canada, 1-2 weeks to the UK and 10-15 days to Australia. Express couriers take 3-7 days, but the buyer pays any duties.
Can I send it back if I change my mind?
HiFiGO gives 7 days to report an item that arrives dead, damaged or wrong. Its policy also describes 30-day returns, but requests 7 to 30 days after delivery lose 30% of the MSRP plus shipping both ways and duties, and the FAQ on the same page says no refund or exchange after 7 days. Ask [email protected] before you open the box.
What warranty does HiFiGO give on cables?
Three months from the order date for cables and adapters, against one year for DACs, amps and IEMs. HiFiGO chooses repair or replacement and the buyer pays the shipping. Claims go to [email protected].
Sources & verification
What this review is based on and the day we last read it. Specs and claims from the maker are the maker’s own; the verdict and the rating are ours.
From the store
- E1DA APU Cosmos Analog Processing Unit High-Performance Low-noise Pre-Amp product page: specs, options and priceSpecs, options and the listed priceRead October 28, 2026
- HiFiGO shipping policyShips from China in 1-3 business days; US 1-2 weeks by Priority or 6-10 days by Premium, duties prepaid; Express buyers pay dutiesRead October 28, 2026
- HiFiGO shipping and order tracking pageA second shipping text: Premium also for Canada and Australia, Canada free shipping from $99.99, lost-parcel rulesRead October 28, 2026
- HiFiGO refund policy7-day dead-on-arrival cover; 30-day returns minus a 30% restocking fee; its FAQ says no refund after 7 daysRead October 28, 2026
- HiFiGO warranty and refund policyWarranty by product class (1 year; cables and adapters 3 months); 30% fee for resealing an opened productRead October 28, 2026
- HiFiGO terms of serviceOperator named only as HiFiGo; governed by the laws of China; contact [email protected]Read October 28, 2026
Independent
- HiFiGO reviews on Trustpilot4.6 of 5 from 378 reviews (91% five-star, 5% one-star); the store has not invited reviews recentlyRead October 28, 2026
What we couldn’t verify
- THD+N is given as below -131db in the specification list but 'down to -132db' in the notes; the page says these were practically achieved with a DAC+LPF source.
- Noise, distortion and dynamic-range figures, such as 950nVrms residual noise and over 153db(A), are the page's own figures; the size 104x61x39mm has no label.
- The page text read for this review ends part-way through its specification section, so later notes may not be covered here.
- HiFiGO's policy pages contradict each other: 30-day returns with a 30% restocking fee in one place, no refund or exchange after 7 days in the FAQ.
- HiFiGO's pages name no company, street address or phone number; the only contact given is [email protected].
Spotted an error or something out of date? Tell us and we’ll fix it and update the date.
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