E1DA Cosmos Scaler Variable Gain Pre-Amp Review

E1DA's Cosmos Scaler is listed at $129 as a variable gain pre-amp, and the page's specification section gives its purpose as an ultra-low THD+N variable gain buffer for the Cosmos ADC. The page lists balanced inputs and outputs with a 3.5mm jack on each side, 16 knob-controlled gain values from 0 to 26.078db, an Auto position and USB-C +5V power. The store's tags include Accessories and Headphone Amplifiers/Pre-Amplifiers, but the page text gives no headphone output power or headphone load.

Specifications

Options and pricing

One option is listed, Cosmos Scaler at $129, orderable when the page was read; the Color group holds just the model name. The page prints its dimension figures run together (PCBA 90x50x29mm followed by 104x61x39mm) and gives weight as PCBA 40g / 160g. It says the short cables of the Cosmos APU suit the Scaler as well, and the page text lists no package contents.

How it compares

The TOPPING L30 II is $149 and its spec line lists up to 3.5Wx2@16Ω, a headphone output figure the Scaler's page text does not give. The TOPPING L30 is $97.49 and a headphone amp by name, and the xDuoo MT-02 is $149 with dual 6J1 tubes in its spec line. At $129 the Scaler suits buyers whose goal is the page's stated purpose, a buffer for the Cosmos ADC; the other three are the ones to read for driving headphones.

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.

HiFiGO's warranty runs one year from the order date for parts and labor; its policy names desktop DACs and amps, IEMs and dongles at one year and gives cables and adapters three months. HiFiGO decides between repair and replacement, the buyer pays the shipping, and faulty items go back for service, not for a refund. Claims go to [email protected], the only contact the store lists: its pages name no company, street address or phone, and its terms are governed by the laws of China.

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.