AA 1P (AT) Headphone / Line Preamplifier
After 12 years of design, projects and manufactured audio units, after we introduced our Reference Anniversary Line, was our intention and goal, to build up an entry line of products, a Headphone Amplifier/Line Preamplifier and a Power Amplifier. On its way is also a Multi Media Center.
As our goal was also to introduce very affordable audio preamplifiers/amplifiers series (but without any major compromises) the decision was not easy. So we developed amplifier approach to follow our commitment to provide natural, pleasing reproduction systems. Even though the series is an entry level and affordable it is an Audio Alto solution, with balanced layout and all amplifying blocks working in Class A.
The line “1P” consists of two versions of the unit: the first is with state of the art low noise operational amplifiers and the second version with two double triodes (or four if Phono option installed) for tube sound lovers. Because the series size poses some usable space restriction, the tubes version is partially balanced.
The preamplifier combined with active speakers system (like AA O 103 SL or AA O105 SL) offers a great minimalistic audio solution for all music lovers.
- Vacuum tubes (AT version): 2x or 4x 6922.
- AA 1P Headphone/Line preamplifier provides single ended RCA and balanced inputs; phones output and single ended RCA as balanced outputs.
- All RCA inputs are differentially processed so the sources are not connected to common ground. Because of this solution there are no ground loops among different sources, so the usual noises are eliminated.
- Inputs which are not selected are all electrically disconnected from the preamplifier, so they have no influence on reproduction while not in use.
- All the switching functionality in the preamplifier is managed with hermetically closed signal relays with Au/Ag contacts.
- The volume control circuit is an active solution so the unwanted noise related to volume position is maximally reduced and optimized.
- Inputs are selected with a three position toggle switch. All control logic signals are electrically isolated from the rest of analog circuits.
- Mains power supply consist of a low noise switching unit with additional filtering. The main supply voltage is from 90V up to 250V AC 50/60 Hz (no switch required). AT version has an separated power supply unit.
- Enclosure is made of polished stainless steel and 3 mm anodized aluminum sheets. The inscriptions are laser engraved.
- The remote IR control unit (as option) consists of a micro-controller that with a separated power supply. With this approach all the induced noises are maximally reduced.
- As an option the unit offers also a Phono RIAA input for MM and MC cartridges. The Phono amplifier uses high grade audio optimized operational amplifiers working in class A. AT version supprorts only MM cartridges. High grade capacitors and precision resistors are used.