SMSL A300 Review: Controls, Loads and Listening Conflicts

Scope note: This literature review considers the SMSL A300 through twelve original written firsthand writers, including bench tests, analog and computer connections, and home speaker systems. It covers the A300 amplifier, not the SA300 or Edifier speakers with a similar name. Follow-ups count once per writer. The reports do not establish a failure rate or a single agreed tonal character. Catalog entry f1c636316b6ee4892945.

Two music sources, passive speakers and a subwoofer can make a small amplifier’s controls matter as much as its output power. The SMSL A300 puts source selection, remote volume, tone adjustment and bass routing in one low case. Its twelve firsthand accounts explain why that combination appeals, but they also make a confident promise about its sound difficult to defend.

Srboljub Stojanovic heard an unusually balanced budget amplifier. Loomis T. Johnson heard an insistent brightness and poorly controlled bass. Owners reported satisfaction, hiss at high settings, useful filters and preferences that changed when another amplifier arrived. Those differences remain part of the review.

These are the named writers’ tests and judgments. Their rooms, speakers, input levels and comparison methods differ, and several accounts share one forum discussion. Twelve writers do not amount to twelve independent laboratories.

A useful set of connections

SMSL’s manual specifies two analog RCA inputs, Bluetooth, computer USB input, remote control and a line-level output for an active subwoofer. An active subwoofer has its own amplifier. The A300 also offers a high-pass mode, which reduces deep bass sent to the main speakers, and a bridged mode that uses an amplifier as one more powerful channel.

Elvom connected the A300 directly to a PC after a separate DAC developed noise. Windows offered 16-bit, 48 kHz operation, and the owner accepted it as a temporary replacement despite preferring the separate converter’s sound. The manual identifies computer audio input; an opening ASR reference to USB-stick playback should not become a promised feature.

Repdetect ran a DO100 for stereo and an Emotiva UMC-200 for multichannel listening, later identifying Gallo Classico 4 speakers. The owner found the presentation softer than desired but kept valuing the two inputs, remote and digital tone controls. A better-sounding alternative, in that account, would still have to replace those functions.

Good room volume does not settle the sound

Stojanovic used Triangle Borea BR03 and KEF LS50 speakers. Ordinary listening presented no apparent struggle; attempts at much more forceful, drum-like levels produced audible compression. He preferred the analog presentation to several other small amplifiers but found a Rega Brio more dynamic. His article links to an Apos affiliate offer; its sample provenance is unstated.

Johnson purchased his A300 and used a Schiit Sys, SMSL SU-6 and Sony 5400ES with PSB Synchrony One B or Energy Connoisseur C-1 speakers. He heard ample loudness and clear upper detail, yet found the balance tiring. Older Adcom and Parasound amplifiers controlled bass more convincingly in his comparison. Neither writer’s listening preference is a wattage measurement or a matched-room comparison with the other writer.

longma preferred the A300 to an owned A07, reporting cleaner separation with Oppo and Onkyo sources and Infinity or JBL speakers. The A07 remained useful for surround duties. By contrast, diablo swapped a Yamaha R-N803 for the A300 and ran REW room sweeps, finding the upper response unchanged in that system. A room measurement can answer a local question without erasing a different electrical result.

Comparisons change as the system changes

ButteredToast initially liked the A300’s added bass over a Loxjie A30, using an E30 and ELAC DBR62 speakers. After a Fosi V3 arrived, the same writer heard clearer separation through the Fosi but found the A300 easier to hear for longer periods. The V3’s higher-voltage supply was still in transit. That sequence supports a preference with conditions, not a clean ranking of amplifier circuits.

Amir Majidimehr bench-tested a member-loaned unit. Noise and distortion were competent rather than exceptional. His tests also showed that the upper-frequency response changed with electrical load. A speaker’s impedance varies with frequency, so its interaction with the amplifier can affect the resulting treble. Majidimehr solicits ASR donations; this was a measurement review rather than a reported music session.

That finding offers a plausible contributor to differing reports. It does not identify the cause of each preference. Source level, equalization, speakers and comparison volume remain uncontrolled across much of this evidence.

Gain and bridging need their own checks

TonyJZX heard hiss from an early A300 at high volume settings. Leaving the amplifier around 35–40 and adjusting the upstream device avoided the complaint in that system. mcebrian tested two units with resistive loads and a Cosmos ADC, finding the second substantially quieter. Later tests favored a 1.2-volt input over a higher signal for distortion performance. Neither account supports always maximizing the source or amplifier setting.

ampguy used two bridged A300s with KEF LS50 speakers and a REL HT1205. saberger0357 also used a pair with Allison One speakers. A later brief AR3 trial pleased that owner, who ultimately preferred using the bridged pair with eight-ohm speakers. A short trial at conservative level cannot establish sustained operation into every difficult load.

Majidimehr’s bridged measurements found much more output, accompanied by greater load-dependent response error and a shutdown before ordinary clipping could be characterized. More available power therefore leaves another condition to check. Stojanovic explicitly had only one unit and did not test bridging.

The filter frequency is unresolved too. SMSL’s version 1.0 manual specifies 50 Hz, while Stojanovic and ampguy describe approximately 100 Hz. Their reports do not establish an independently measured common cutoff. A subwoofer integration plan should keep that discrepancy visible.

Current price and the next useful test

On 20 October 2026, HiFiExpress listed the black A300 at US$176.99, with Add to cart and eight units indicated. Its matching product-variant record was available. A generic sold-out phrase also appears in the page template; the selected black variant supplied the availability check. Shipping is calculated at checkout. This is a retailer offer in native USD, separate from historical review prices.

The A300 makes its strongest case where a compact system needs its particular controls and connections. The twelve accounts do not justify promising that every listener will hear the same balance. An unperformed controlled test would keep one source and speaker pair, match playback levels, record input voltage and EQ mode, and measure the mains/sub filters before comparing stereo with bridging. That test would resolve more for the intended system than another unqualified adjective about its sound.

The twelve firsthand records

1. Amir Majidimehr, ASR, 27 July 2023: member-loaned bench sample; noise, load response and later bridging/filter tests. Donations disclosed.
2. Srboljub Stojanovic, iiWi, 8 December 2022, updated March 2024: Triangle/KEF listening and analog/digital comparisons; one unit, no bridged trial. Affiliate link.
3. Loomis T. Johnson, AudioReviews, 25 May 2023: self-purchased unit with PSB/Energy speakers; strong objection to tonal balance.
4. ampguy, ASR, July 2023: dual-mono LS50/REL system; follow-ups on V3 comparison and temperature merged.
5. Elvom, ASR, 31 August 2023: actual PC USB connection after separate-DAC trouble; Windows format and qualified listening preference.
6. TonyJZX, ASR, July 2023: early-unit hiss and upstream gain adjustment; uncalibrated level.
7. saberger0357, ASR, July 2023: Allison One bridged pair; brief AR3 trial and later conservative load choice merged.
8. longma, ASR, July 2023: Oppo/Onkyo and Infinity/JBL comparisons with A07; sighted preference.
9. ButteredToast, ASR, July 2023: E30/DBR62 comparisons; later Fosi result retained with its supply condition.
10. diablo, ASR, 28 July 2023: Yamaha replacement and REW room sweeps; setup-specific result.
11. Repdetect, ASR, July 2023: DO100/UMC-200 and Gallo speakers; control benefits alongside a soft tonal impression.
12. mcebrian, ASR, September 2023: two units, resistor-load/ADC measurements and subsequent input-voltage tests; no population inference.