Coverage note. Speaker Ranking currently covers 3 Fosi Audio models across passive speakers and headphones. These are the products in our database, not a complete list of everything Fosi Audio makes.
What this page covers. The Fosi Audio models ranked here span passive speakers and headphones, including Fosi Audio i5, Fosi Audio IM4 and Fosi Audio SP601. Use each model’s category position to compare it with alternatives of the same size and use case.
This page lists all 3 Fosi Audio speakers ranked on this site across passive speakers and headphones. Each model is shown in the category where it competes, with its current rank and the size of that ranking.
Use the category position rather than the brand name alone: speakers from the same manufacturer can perform very differently by size, price and product family.
Prices on this page were last checked October 10, 2026 at 5:37 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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Large Size Bookshelf Speakers
Ranked #193 of 214 in Large Size Bookshelf Speakers - Fosi Audio SP601: $399.99 per pair Amazon Fosiaudio eBay
Pros: Two-way bookshelf design with a 6.5” paper/aluminum-alloy composite cone woofer and 1.5” silk dome tweeter. Bass reaches a respectable 60-70Hz in most rooms (F3 59Hz, F10 40Hz) for a budget bookshelf speaker. Distortion at 86dB and 96dB measures reasonably well at face value, and compression issues at extreme output are generally in line with what’s expected for a speaker at this price point. The overall tonal character can be substantially improved with basic EQ: the reviewer found a boost around 400Hz plus a cut around 4kHz brought it to an acceptable baseline. Measured bass extension of 59Hz (-3dB), with a measured sensitivity of 85.4dB.
Cons: An unusually erratic, up-and-down frequency response (a scooped midrange followed by an upper-mid bump, a dip, another small bump, then a strong 3-4dB peak around 4-7kHz) makes the speaker’s overall character genuinely hard to characterize: the reviewer compared the experience to a similarly disliked model, the Triangle Borea BR03, which has a comparably inconsistent response. The 4-7kHz peak gives a sharp, sibilant edge to S and T sounds in vocals. A strong diffraction dip around 4kHz followed by a peak can’t be fully corrected with EQ; the reviewer recommends sidewall absorption panels instead, since off-axis energy in the 2-7kHz range actually exceeds the direct sound reaching the listener. Multitone distortion becomes more noticeable and grainy at higher volumes, concentrated in the upper-midrange where hearing is most sensitive. A peaking distortion issue right at the crossover region suggests a possible combination of tweeter distortion and midwoofer/crossover-component strain. The enclosure sounds notably hollow when tapped, and a flashlight inspection suggested a lack of internal damping material, along with likely insufficient bracing. Vertical listening position is fairly tightly constrained around the tweeter axis. Still requires a subwoofer for real kick-drum impact and bass authority.
Full Fosi Audio SP601 review and specifications →
| Released | Feb 2025 (1 year ago) |
|---|---|
| App | No |
| Bass Extension (-10dB) | 40Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 59Hz (measured, Erin’s Audio Corner) |
| DIY Kit | No |
| DSP | No |
| Dimensions | 14.5”H x 9.1”W x 14”D (368.3 x 231.1 x 355.6 mm) |
| Drivers | 6.5” woofer, 1.5” Silk Dome Tweeters |
| EQ | No |
| Impedance | 4 ohms nominal, 4.1 ohms minimum (measured, Erin’s Audio Corner) |
| Power Handling | 80w RMS Per Speaker |
| Sensitivity | 85.4dB (measured, Erin’s Audio Corner) |
| Weight | 11.5 lbs (5.2 kg) |
| Woofer Cabinet | ported, rear |
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Over-Ear Headphones
Ranked #72 of 202 in Over-Ear Headphones - Fosi Audio i5: $589.99 Amazon eBay
Pros: A large 97mm planar magnetic driver scores 80.7 for preference in the median of four squig.link measurements, with the low mids about 1 dB over target for a full, warm tone. Air above 10 kHz runs about 4.4 dB hot, which adds openness and detail to strings and cymbals. At 28 ohms and 98 dB/mW it is easier to drive than many planars and works from a modest desktop DAC or a capable dongle.
Cons: Sub-bass drops roughly 5.8 dB below target and is already 6 dB down by 42 Hz, so deep synth bass and kick drum rumble lack impact. A 5.8 dB dip near 2.2 kHz and a presence region about 3.2 dB low push vocals back, while the 5.1 dB peak at 10.9 kHz can sound splashy. It weighs 550 g, and the open back leaks sound and blocks no outside noise.
Full Fosi Audio i5 review and specifications →
| Released | Apr 2025 (1 year ago) |
|---|---|
| Back | Open |
| Built-in Microphone | No |
| Connection | Wired |
| Deviation From Target | 2.17 dB standard deviation |
| Driver Type | Planar magnetic |
| Drivers | 1 x 97mm planar magnetic |
| Form Factor | Over-ear |
| Frequency Response | 10Hz - 50kHz (Manufacturer specified) |
| Harman Preference Score | 81 (median of 5 squig.link measurements, calibrated to AutoEQ) |
| Impedance | 28 ohms |
| Sensitivity | 98 dB/mW |
| Sub-bass Extension | Falls 6 dB below target at 40 Hz (-6.6 dB at 30 Hz) |
| Tonal Tilt | -0.28 (negative is warmer, positive brighter) |
| Weight | 1.2 lbs (550 g) |
- Reviews, Comparisons and Sound Samples
In-Ear Headphones
Ranked #124 of 297 in In-Ear Headphones - Fosi Audio IM4: $99.99 Amazon eBay
Full Fosi Audio IM4 review and specifications →
| Released | 2025 (1 year ago) |
|---|---|
| Back | Closed |
| Built-in Microphone | No |
| Connection | Wired |
| Deviation From Target | 1.75 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 10mm dynamic |
| Form Factor | In-ear |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) |
| Harman Preference Score | 78 (median of 5 squig.link measurements, calibrated to AutoEQ) |
| Impedance | 21 ohms |
| Sensitivity | 109 dB |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-1.4 dB at 30 Hz) |
| Tonal Tilt | -0.02 (negative is warmer, positive brighter) |
| Weight | 0 lbs (7 g) per earbud |
- Reviews, Comparisons and Sound Samples