Up to 2 × 50W
Compact stereo output for everyday listening with one passive speaker pair.
EVERYDAY AUDIO · FOR PASSIVE SPEAKERS
Compact stereo power for the passive bookshelf speakers you actually want to listen to.
Up to 2 × 50W stereo output, aptX Bluetooth, RCA, and coaxial input—built for desks, bedrooms, and smaller rooms.
For change-of-mind returns, contact us within 14 days of delivery. Items must be unused, uninstalled and undamaged, in original packaging with all accessories and documentation. Approval is required before return shipping.
You cover return shipping for change-of-mind returns. We have no US return warehouse; the authorized return address may be overseas. Verified defects, transit damage and incorrect items are handled separately.
Amplifier only — passive speakers required. Connect one pair of compatible passive speakers. Speakers and speaker cables are sold separately.
WHY IF-AMP03
IF-AMP03 brings the essentials together in a low-profile chassis: three inputs, bass and treble control, and speaker-level output for one passive pair.
Compact stereo output for everyday listening with one passive speaker pair.
Stream directly from a phone, tablet, or computer with the included antenna.
Switch between Bluetooth, stereo RCA, and coaxial sources from the front panel.
SOURCE · IF-AMP03 · YOUR SPEAKERS
Stream over aptX Bluetooth or connect a wired source by RCA or coaxial, then drive one pair of passive speakers directly.
STREAM MUSIC TO YOUR PASSIVE SPEAKERS
Speaker output only · Not for powered speakers
CHOOSE SPEAKERS FOR YOUR ROOM
Impedance establishes the electrical load, while sensitivity, listening distance, room size, and desired volume determine how loudly a system will play. Higher-sensitivity speakers generally produce more volume with the same amplifier power.
CONNECT WITH CONFIDENCE
Connect one pair of passive speakers, attach the Bluetooth antenna and supplied power adapter, then select BT on the front panel. Choose AMP-03 in your phone’s Bluetooth settings.


IN THE BOX
One 3.5mm-to-dual-RCA audio cable is included. Coaxial and speaker cables are not included.
CONFIRMED INFORMATION
Product specifications, connections, and package contents for the IF-AMP03.
SUPPORT · FAQ
Learn how IF-AMP03 connects, what it includes, and how Arden Audio supports it.
Connect one pair of passive speakers with a nominal impedance of 4–16Ω. For the most straightforward match, 8Ω passive speakers are recommended. Do not connect multiple speakers in parallel unless their combined impedance has been properly confirmed.
Impedance is only one part of speaker matching. Higher-sensitivity speakers generally play louder with the same amplifier power, while lower-sensitivity speakers require more power. Room size, listening distance, and desired volume also affect the result.
No. The rear speaker terminals provide an amplified signal intended for passive speakers. Do not connect them to the AUX, RCA, XLR, or other line-level inputs of powered speakers.
Yes. Attach the Bluetooth antenna, turn on the amplifier, move the INPUT selector to BT, and select “AMP-03” in your phone’s Bluetooth settings. Music playback, track selection, and source volume can then be controlled from your phone.
Check the audio outputs on your device. Connect its coaxial digital audio output to COAXIAL on the AMP03, then select COAXIAL. Alternatively, connect an RCA analog audio output to LINE-IN and select LINE. An RCA input on the source device cannot be used as an output. A TV with only HDMI or optical output cannot connect directly through those ports.
Connect the red and white RCA audio outputs on your CD player or DAC to the matching LINE-IN sockets on the AMP03, then select LINE. If your CD player has a coaxial digital output, you can instead connect it to COAXIAL and select COAXIAL.
Pair a Bluetooth-enabled computer with AMP-03 and select BT on the amplifier. If the computer has a headphone output, use a 3.5mm-to-dual-RCA audio cable to connect it to LINE-IN and select LINE. You can also use the RCA output of an external DAC. USB audio does not connect directly to the AMP03.
Yes, with a phono preamp. If your turntable has a built-in phono preamp, set its output to LINE and connect its RCA outputs to the AMP03 LINE-IN. Otherwise, connect the turntable to an external phono preamp first, then connect the preamp output to LINE-IN. Select LINE on the amplifier.
With the amplifier switched off and unplugged, connect one passive speaker to the L speaker terminals and the other to R. Match positive (+) and negative (-) at both ends. Keep exposed wire strands from touching other terminals.
Connect the supplied 18V/4A adapter to DC-IN, then to mains power. Start with the volume low, switch on and select your source. Speakers and speaker cables are sold separately.
The amplifier normally remembers and reconnects to the most recently paired device. If it does not reconnect, select “AMP-03” from your phone’s saved Bluetooth devices. If pairing still fails, forget the saved connection and pair it again.
The IF-AMP03 supports Bluetooth, stereo RCA line input, and coaxial digital input. Select the desired source with the front INPUT switch. It does not include HDMI, optical, USB audio, or a dedicated phono input.
The BASS and TREBLE controls adjust the low- and high-frequency balance in every input mode. Start with both controls near the center position, then make small adjustments for your speakers, room, and listening preference.
The box includes the IF-AMP03 amplifier, 18V 4A power adapter, power cord, Bluetooth antenna, 3.5mm-to-dual-RCA audio cable, and user manual. Coaxial cable, speaker cables, and speakers are not included.
INFI Audio is an in-house audio brand of our manufacturing factory, not an unrelated third-party seller. The IF-AMP03 is produced by the same factory and offered directly through Arden Audio. Arden Audio handles the sale, customer support, and warranty for your purchase.
Arden Audio provides customer support and a one-year limited warranty from delivery for manufacturing defects under normal intended use. View warranty coverage and terms.