Questions about BOLDfonic?
BOLDfonic delivers high-fidelity acoustic stimuli for fMRI while also attenuating scanner noise. Our electro-dynamic driver technology uses the magnetic field of the MRI scanner to drive the headphone membranes. This results in powerful speakers with an excellent frequency response across a wide dynamic range. A novel USB sound processor with automated synchronous triggering capabilities and a fully–loaded amplifier system provide all the controls you need for rigorous multimodal EEG/fMRI studies.
Guide price includes a desktop microphone and speakers, plus one pair of headphones and the earbuds. Many options are available, so please contact us for more details.
Guide Price: £7250
Hear the Difference
You wouldn't listen to the music on your iPhone with a stethoscope connected to its speaker.... Yet, most MRI-compatible headphones offer just that; audio piped to the participant down long, acoustic tubes. The result? Awful sound quality with restricted frequency response and restricted utility in research.
Hear for yourself in our 48 second demo:
BOLDfonic includes everything you need for high-quality audio delivery in the MR:
Better Audio Quality
BOLDfonic headphones utilize moving-coil transducers positioned in the headphone body, just like hi-fi headphones! As you can see illustrated in Figure 1, this results in excellent frequency response across a wide dynamic range.
Though standard moving-coil transducers utilizing a magnet aren't safe in an MRI room, the BOLDfonic headphone system features a unique electro-dynamic driver that utilizes the magnetic field of the MRI scanner to drive the headphone membrane. An additional piezoelectric driver can be fitted to some headphones, which enables them to be used outside the bore as well.
Reduced Gradient Noise
When compared to a standard scanner audio system, the circumaural, closed-back BOLDfonic headphones offer improved acoustic isolation from the gradient-noise of the MRI scanner. Acoustic attenuation is increased by at least 15dB over most of the audible range, as illustrated in Figure 2.
Where space permits, soft memory foam cushions can also be inserted between the head and contact points of the coil to provide even better isolation, reduce bone conduction and improve participant comfort.
Easy to install
BOLDfonic headphones connect through the RF penetration panel using a pair of BNC bulkhead connectors. Two independent stereo channels maintain the high channel separation of the amplifiers. The filter/transformer set blocks DC levels, separates the ground of the RF cage from the ground of the audio system, and reduces unwanted RF-signals by about 85dB. Extra filters inside the scanner room reduce RF signals even further by about 90dB.