TEAC - AP-505 Stereo Power Amplifier

Not only for conventional stereo mode with 130W + 130W of output power, this compact unit also provides versatile speaker drive modes, Bi-amp and BTL modes by deploying a couple of AP-505 units side by side. The Bi-amp mode drives woofer and tweeter independently, while the BTL modes produces 250W of output power in each channel.

Every external panel – at the front, top and sides - is formed from high-grade aluminium alloy, firmly attached to the robust steel inner chassis. This method of construction helps reduce the transmission of mechanical vibration, ensuring that every single element inside the unit is allowed to perform at its best. Thanks to its convenient A4-sized footprint, the AP-505 easily slots into modern interiors where space-efficiency is important, such as on a desktop. This is in stark contrast to most conventional bi-amp/BTL-capable power amplifiers which are usually bulky, full-width units.

By employing a fully-balanced circuit design from the input section to the output stage, the AP-505 keeps the audio signal as unadulterated as possible as it moves through the amplifier, the result being extremely low distortion levels and an excellent signal-to-noise ratio (assisted by the effective elimination of common-mode noise).

In the power supply, the AP-505 employs a high capacity toroidal-core transformer, with Schottky barrier diodes in the rectifying circuit. Unlike conventional diodes, Schottky barrier diodes reduce rectifier noise, leading to a ‘cleaner’ supply and a more stable delivery of current.

The AP-505 employs TEAC's patent-pending ‘Pin-Point’ feet. These comprise two separated metal sections in an integrated housing. One has a spiked top and is attached to the bottom of the chassis, the other is a basin-shaped base that hangs down from the spiked section, with a flange-shaped cup to simplify installation. As a result of the unique design, the ‘Pin-Point’ feet considerably minimize vibrations and resonance, by virtue of the fact that the unit is supported on just three points, with a very small surface contact area. This arrangement reduces mid and low frequency muddiness so improving the soundstage and enhancing fine sonic detail.
* Japan Patent numbers 4075477 and 3778108

It makes no sense to design an amplifier that delivers excellent sound to a pair of speakers but which itself generates distracting operating noise from a cooling fan. From the outset our engineers were determined to use a circuit and layout that would allow sufficient natural cooling, one that would allow the creation of a compact but powerful amplifier which didn’t need the help of a cooling fan.

Analog level meters on the front panel move in response to signal levels, giving a visually pleasing confirmation that the amplifier is doing its job. A four-step dimmer (bright, mid, dim off) allows users to adjust the intensity of display to their taste, while a switchable sensitivity (±0dB, +20dB, movement off) allows you to enjoy more, less, or even no meter movement, if preferred.
Naturally, even if the backlight is off and meter movement has been disabled, you are still able to tell the unit is on... by checking the position of power switch!。