A bi-amplified desktop pair with 4.5-inch black Kevlar woofers and silk dome tweeters, in MDF cabinets, with three rear input types, front-panel aux and rear high/low EQ.
What it amounts to The plug-in-and-work pair: every cable, the feet, and a program to make music with, in one box.
The BX4 is built around a specific idea: that a first pair of monitors should not need a second order.
The box contains the active speaker, the passive one, the cable that links them, a 3.5 mm (0.14 in) aux cable, a 3.5 mm (0.14 in) to RCA cable, foam feet, and MPC Beats. That is a complete desktop monitoring setup from one purchase, and the foam feet are the part most people never think to buy — they stop the desk itself from behaving like a speaker cabinet.
The drivers are 4.5-inch black Kevlar woofers with silk dome tweeters in MDF cabinets, with high and low EQ on the back for room compensation and a switch to put the active speaker on either side.
M-Audio does not publish a frequency response for this model in the listing, and this page does not invent one. What it does publish is the connectivity — 6.3 mm (0.25 in), 3.5 mm (0.14 in) and RCA at the back, aux at the front — which is what decides whether the speakers work with what you already own.
In its favor, and its limits
Strengths
Every cable needed is in the box, including the foam feet that decouple them from a desk
Three rear input types: it will connect to an interface, a laptop or a mixer as delivered
MPC Beats included, which is a working music program rather than a demo
A left/right switch, so the active speaker can sit on either side
Compromises
One speaker is passive and driven by the other — the pair must stay cabled together
M-Audio does not publish a frequency response in this listing, so none is reported here
Specifications
Sold as
One active and one passive speaker with connecting cable
Drivers
4.5" black Kevlar woofer, silk dome tweeter
Cabinet
MDF, bass reflex
Rear inputs
6.3 mm (0.25 in), 3.5 mm (0.14 in) and RCA
Front panel
3.5 mm (0.14 in) aux for headphones
Controls
Rear high and low EQ, left/right active switch
In the box
Connecting cable, 3.5 mm (0.14 in) aux cable, 3.5 mm (0.14 in) to RCA cable, foam feet, MPC Beats
Amazon reference
B08KXTJX16 (identical on 6 markets)
EAN
0694318024805
The questions players ask
What does bi-amplified mean here?
Separate amplification for the woofer and the tweeter inside the active cabinet. In this design one speaker carries the amplification for both and feeds the second through the supplied cable, which is why they cannot be separated across a room.
Why do the foam feet matter?
They decouple the cabinets from the desk. Without them, the desk surface acts as a sounding board and adds low end that is not in the recording — the cheapest improvement available to a desktop setup.
Our score
7.8/ 10
The plug-in-and-work pair: every cable, the feet, and a program to make music with, in one box.
Accessories confirmed for this instrument
Shown because the accessory names this instrument itself.
A reference exists on these Amazon stores: France, Germany, Italy, Spain, United Kingdom, United States. Listed is not the same as in stock — availability changes daily.
Details checked on August 18, 2026.
Who should pick this one, among music instruments and gear
A first pair of desktop monitors where nothing else should have to be bought.
Our music instruments and gear guides that pick it
Amazon reports what buyers took in the month before this page was last checked: at least 50.
The figure is a floor, rounded by Amazon, and read through Keepa — it says what buyers picked, not what a maker claims.
Sources
Specifications: the manufacturer sheet for musical instruments and gear and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.
3 in drivers · 50 W · headphone jack that mutes the speakers · 1/4 in, 1/8 in and RCA
The only pair here whose front headphone socket switches the speakers off by itself — on 3-inch drivers, 50 watts, three input types and cables in the box.
Best for: A desk where the headphones and the speakers share one source and get swapped a dozen times a day.
Pair · 5" woofer · 100 W · Bluetooth · headphone out
The largest monitors in this group: 5-inch woofers, 1-inch tweeters, 100 W total, with RCA and 6.35 mm (0.25 in) TRS inputs, a headphone output and Bluetooth streaming.
Best for: A room with a meter or so behind the speakers, doing both music production and listening.
The desktop pair: 3.5-inch woven composite woofers, 1-inch silk dome tweeters, 50 W total, 80 Hz – 20 kHz, with acoustic tuning controls and a headphone socket on the front panel.
Best for: A desk where space is the binding constraint and headphones are the main tool anyway.