SALAD BOWL SPEAKER PROJECT

Order Code: SB12PFCR25-4-COAX

Availability: In Stock

25mm Voice coil, paper cone, rubber surround, ferrite motor, round mounting injection chassis, coaxial midwoofer

IKEA BLANDA MATT SALAD BOWL

Reproduced from Silicon-Chip for project inspiration and your interest only. Using our newly available SB Acoustics accoustic point source coaxial two-way drivers, however could be adapted to suit any suitably sized driver.

We do not have a kit available for resale.

These speakers are retro, stylish and surprisingly good performers. They're also pretty easy to make and offer a unique, attractive readily available speaker cabinet solution thats fun. Research spherical cabinet speakers and we discover that there are fundimental advantages in the design capitalised by some big name manufacturers and designers.

Salad bowl speaker concept has been spreading around the internet. This Silicon-Chip article describes a fully functioning pair of desktop / bookshelf speakers and gives some suggestions for tweaking the design to suit your needs. What initially attracted us to this idea was the mix of an old-school spherical speaker with extreme ease of construction. While the initial motive for building these was style and looks, it quickly became apparent that these little cuties had more to offer than that. Those who make speakers will be quick to comment that a sphere should be highly resonant; however, our tests show this is not the case. The fact that the driver forms a significant portion of the surface area of the sphere results in the Q of the internal resonance being relatively low. As a result, our measurements don't show resonant peaks in the response. Another benefit of a spherical speaker is that it has no edges. Or is it all one edge? Either way, concerns like edge diffraction and baffle effect are avoided. The fact that these speakers are spherical makes them extremely rigid. Edge diffraction is the effect of sound waves propagating from the driver across a speaker's front panel, then hilling the edge, which forms a discontinuity from propagation in 'half space' to 'free space·. This change causes diffraction at the speaker edges, affecting the frequency response and off-axis behaviour. There are many ways a spherical speaker can be mounted. Without creating a solution to this, they will tend to roll around! We have come up with a couple of options, including feet for the desk version and "rocket" Floor stands, both shown in the photos. The desktop version uses three small doorknobs as feet. The loudspeaker driver used is the SB Acoustics SB12PFCR25-4-COAX, a bass/mid driver with a coaxial tweeter (mounted in the centre). This allows us to achieve really good performance from about 70Hz upwards. These work brilliantly as desktop speakers and would also match well with many subwoofers crossed over at 80-1OOHz. We chose this specific SB Acoustics driver because it incorporates the tweeter, and neatly addresses the challenge of finding somewhere to mount the tweeter. The only other solution we could think of was to mount the tweeter externally, which we did with the Floor-standing version, but it was a real hassle. We have added a port to our enclosure. This allows us to extend the lower frequency response to about 70Hz, with some useful output below that. That is a good result for such a small speaker and is reasonable in its intended applications of desktop usage or placement in a small room. Don't try lo run a dance party using these speakers, though. There is a bit of a hump in the frequency response in the 100-200Hz region. This is a result of the port and helps fill out the bottom end, given the roll-off below 80Hz. The black line in Fig.2 shows the low frequency response you will achieve if you simply omit the port. If you use these on a desk backed up to a wall, om it the port. We used a 25mm port from Wagner Electronics, cut to 90mm in length. This tunes the system to resonance at 74Hz. In practice, the vent ends close to the driver magnet, so its effective length is over 90mm. This tuning gains us a couple of decibels of extra bass in the roll-off region. In an ideal world, this port would be 160mm long, tuning the enclosure to 58Hz, but there is not enough room in the enclosure for that.

Silicon-Chip - Sept 2023
IKEA salad bowl

Compact full-range loudspeakers with a unique appearance
Simple construction thanks to Ikea
Spherical enclosure minimises diffraction
Coaxial tweeter for good off-aiis response
Can be desk or floor mounted (the latter with a simple stand)
Frequency response: 70Hz to 20kHz (±3d8 lypical)
Power handling: 50W RMS per channel
Impedance: nominally 4Ω
Relatively low total cost

Not available as a kit. Read / Show More

Related Products for SALAD BOWL SPEAKER PROJECT

Related Products : View Product Group Page

Found in Category : Loudspeakers - Kits

Description	25mm Voice coil, paper cone, rubber surround, ferrite motor, round mounting injection chassis, coaxial midwoofer
Link	Silicone-Chip - Ikea Salad Bowl Speaker
Wagner eBook	03-167
eBook	Link to eBook
Le	0.26mH
Qts	0.33
Qes	0.36
Mag.	0.4kg
Rms	0.4kg/s
Power (RMS)	0-50 Watt
QTY	1
Cms	1.66mm/N
Xmax	10mm
Width	122mmØ
Flux (lm)	1T
Page	22
Coil	25.4mmØ
Re	3.1Ω
Bl	3.8Tm
Prms	30W
Power	30Wrms
Impedance (Ohm)	4 ohm
Size	4"
Inch	4"
Qms	4.07
Mms	4.5g
Vas	4.8L
Sd	45cm²
Zn	4Ω
Impedance	4Ω (Re 3.1Ω)
Fs	58Hz
Depth	59mm
Crossover	5KHz(6dB/Oct) to 2.2KHz (18dB/Oct)
Sens.	87dB
Price Type	each
Series	Polymer chassis
Manufacturer	SB Acoustics
Type	Woofer

Description	File	Size
Datasheet	SB12PFCR25-4-COAX.pdf	565 KB
SB Acoustics Catalogue	SB-Acoustics-Catalogue.pdf	26130 KB
Crossovers for PFC/PAC coaxial drivers	Crossover-for-PFC-or-PAC-Coaxial-Drivers.pdf	400 KB
Silicon Chip 2023 Salad Bowl Speaker Kit	SC2023-Salad-Bowl.pdf	3036 KB

AV TV SAT Installation

Cables & Connectors

Audio Speakers & PA

Data & Computer

Security

Cellular Accessories

Communication Accessories

Tools & Test

Power & Lighting

Automotive

Electronic Components

Service & Repair Parts

SALAD BOWL SPEAKER PROJECT

$89.50

Related Products

SALAD BOWL SPEAKER PROJECT

SB ACOUSTICS 4" COAXIAL 2-WAY - PACR

$9.90 Australia Wide Flat Rate Shipping*

Store Pick Up from Sydney Showroom

International Order Shipping Available