In this review, we will be comparing Ai61 and YU4, two Powered Bookshelf speakers from Fluance and Kanto. Being Powered speakers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them.
Let's have a brief look at the main features
of Fluance Ai61 and Kanto YU4 first before getting into our more
detailed comparison.
| Key Specs | Fluance Ai61 | Kanto YU4 |
|---|
| Brand | Fluance
Canada · founded 1999 | Kanto
Canada · founded 2007 |
|---|
| Design | 2-way | 2-way |
|---|
| Built-in amplifier | 120-watt RMS | 70-watt RMS (140-watt peak) |
|---|
| Tweeter | 1" Soft Dome | 1" Soft-Dome |
|---|
| Woofer | 6.5" Woven, Glass Fiber Composite | 4" Kevlar |
|---|
| Frequency response | 32-20k Hz | 60-20k Hz |
|---|
| Power range | up to 120 watts | — |
|---|
| Max depth / sample rate | 16-bit / 48 kHz | 24-bit / 96 kHz |
|---|
| Bluetooth | Built-in 5.0 | Built-in 4.0 |
|---|
| Weight | 5.96kg / 13.1lbs | 2.50kg / 5.5lbs |
|---|
| Dimensions (H x W x D) | 13.1" x 7.8" x 9.2"
33.3 x 19.8 x 23.4 cm | 8.7" x 5.5" x 7.5"
220.0 x 140.0 x 190.0mm |
|---|
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both Ai61 and YU4 are 2-way speakers.
Fluance Ai61Kanto YU4
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Fluance Ai61 |
Kanto YU4 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 6.5-inch
|
1 x 4-inch
|
Ai61 features a 1" Silk Neodymium Ferrofluid Cooled Soft Dome Tweeter and 1 x 6.5" Woven, Glass Fiber Composite Woofer. On the other hand, the YU4 features a 1" Silk Soft-Dome Tweeter and 1 x 4" Kevlar Woofer.
Frequency Response
Ai61 has a frequency range of 32-20k Hz whereas YU4 has a frequency range of 60-20k Hz. With a minimum frequency of 32Hz, the Ai61 can go significantly deeper on the low side and provide stronger bass compared to the YU4's min frequency of 60Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Cabinet Type and Port Position
Both Ai61 and YU4 have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Fluance Ai61's and Kanto YU4's external dimensions. Fluance Ai61 has external dimensions of 33.3 x 19.8 x 23.4 cm (13.1 x 7.8 x 9.2 inches) whereas Kanto YU4 has external dimensions of 220.0 x 140.0 x 190.0mm (8.7 x 5.5 x 7.5inch).
Fluance Ai61 is clearly the larger of the two speakers. Its body is 58mm wider, 113mm taller and 44mm deeper than Kanto YU4.
Size, drawn to scale
Both speakers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same surface and pushed back to the same wall, so the deeper one visibly sticks out further.
Fluance Ai61 needs about 74% more floor or shelf area. Fluance Ai61 is 44mm deeper, so it stands that much further out from the wall. Fluance Ai61 is 113mm taller.
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the Fluance Ai61 is approximately 463.0cm2 / 71.8inch2 and base area of the Kanto YU4 is approximately 266.0cm2 / 41.2inch2. The Ai61 requires 74% more surface area than the YU4 which gives it a small disadvantage on placement in tight spaces.
Weight Comparison The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The Fluance Ai61 weighs 5.96kg / 13.1lbs and the Kanto YU4 weighs 2.50kg / 5.5lbs. This makes the Ai61 138% heavier than the YU4.
Here is a comparison of how Ai61 and YU4's weights compare with the average, max and min weights in Powered Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of Fluance Ai61?
Here are the items that are included inside the box of Ai61:
- Ai61 Powered Bookshelf Speakers (pair)
- Remote Control
- 1x CR2032 Battery
- 6ft Power Cable
- 8ft 18 Gauge Speaker Wire
- Quick Start Guide
- Fluance Catalog
- Lifetime Customer Support
- 2 Year Manufacturer’s Warranty
What's in the Box of Kanto YU4?
Here are the items that come with the YU4:
- Remote with Batteries
- Power Cord
- Speaker Wire (16′)
- 3.5mm Auxiliary Cable (6.5′)
- 8 x Rubber Feet
- Manual
 Woofer Size |
6.5 inches
vs
4 inches
|
Larger woofer |
|
Low Frequency Response |
32 Hz
vs
60 Hz
|
Generates deeper bass |
 Price per pair* |
299USD
vs
450USD
|
costs less (*prices may change depending on the seller, location and time) |
 USB Port |
USB-C
vs
No
|
USB port adds flexibility |
 Height |
220mm
vs
333mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
266cm2
vs
463cm2
|
Takes less floor space |
|
USB Port |
Charge only
vs
No
|
USB port adds flexibility |
 3.5mm Connection |
Yes
vs
No
|
Connection via 3.5mm AUX input |
 RCA Connection |
Yes
vs
No
|
Connection via RCA input |
 Phono Input |
Yes
vs
No
|
Connect your turntable directly |
| General |
Fluance Ai61 |
Kanto YU4 |
| Brand |
Fluance |
Kanto |
| Speaker Type |
Powered Stereo Speakers |
Powered Stereo Speakers |
| Frequency Response |
32-20k Hz |
60-20k Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
120-watt RMS |
70-watt RMS |
| Watts Peak (Max) |
n/a |
140-watt RMS |
| Max Bit Depth |
16-bit |
24-bit |
| Max Sample Rate |
48 kHz |
96 kHz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
6.5" |
4" |
| Woofer Composition |
Woven, Glass Fiber Composite |
Kevlar |
| Woofer Surround Material |
Butyl Rubber |
n/a |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Soft Dome |
Soft-Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
333.0mm (13.1") |
220.0mm (8.7") |
| Width |
198.0mm (7.8") |
140.0mm (5.5") |
| Depth |
234.0mm (9.2") |
190.0mm (7.5") |
| Weight |
5.96kg (13.1lbs) |
2.50kg (5.5lbs) |
| Enclosure |
Bass Reflex |
bass reflex |
| Finish |
MDF wood |
n/a |
| Available Colors |
Black Ash,Lucky Bamboo,White Walnut, Natural Walnut |
n/a |
| Mounting Bracket |
No |
No |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Aux Inputs |
RCA |
3.5mm, RCA |
| USB Port |
USB-C |
Charge only |
| Phone Input |
No |
Yes |
| Subwoofer Output |
Wired |
Wired |
| Digital Input |
Optical |
Optical (2) |
| HDMI Input |
No |
No |
| Headphone Jack |
No |
No |
| Ethernet Port |
No |
No |
Other |
|
|
| Parts Warranty |
|
2 Years |
| Labor Warranty |
|
2 Years |
A generation apart: Fluance Ai61 is the newer design, against a 2017 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | A | Fluance Ai61 digs deeper - 32Hz against 60Hz. |
| Built-in power | A | Fluance Ai61 has the bigger amplifier (120W vs 70W RMS). |
| Connections | B | Kanto YU4 adds phono. |
| Size | depends | Kanto YU4 is easier to place; Fluance Ai61 is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Fluance Ai61: a sub output; Kanto YU4: a sub output. |
| Price | A | Fluance Ai61 is cheaper - $299 against $450, about 34% less. |
A Fluance Ai61 B Kanto YU4
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Fluance Ai61 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 60Hz anyway, so judge these on the other rows instead. In a large or open-plan room, Fluance Ai61 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Kanto YU4 is the easier speaker to get right.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.