{"id":19492,"date":"2025-05-21T12:40:30","date_gmt":"2025-05-21T12:40:30","guid":{"rendered":"https:\/\/masteringmansion.com\/pro-audio\/?post_type=product&p=19492"},"modified":"2026-07-02T13:09:59","modified_gmt":"2026-07-02T13:09:59","slug":"312-2","status":"publish","type":"product","link":"https:\/\/masteringmansion.com\/pro-audio\/categorias\/preamplificadores-y-canales\/312-2\/","title":{"rendered":"312+ 2"},"content":{"rendered":"
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Classic American Mojo. Punchy, fast and colored. <\/strong><\/h1>\n

The 312+ is a dual stage dual channel preamplifier that includes a 1:1 replica of the a vintage API 312 card from the 70\u2019s and a built in API line amplifier on each channel. After making 312 preamps for almost a decade we decided to retire the Stam Audio 312MP and only manufacture the 312+ moving forward due to the overwhelming positive feedback from our customers and it\u2019s \u201cconsole\u201d sound.<\/p>\n

The 312+, unlike the regular 312, is a dual stage preamp. The first stage is a fully discrete 1:1 replica of a API 312 card with custom US-made transformers, a Stam Audio SA-25 op amp and no coupling capacitors. Unlike any other current made or clone the 312+ includes the console line amplifier as a second stage in rack format making it a fully discrete dual stage preamplifier in a 1U format.<\/p>\n

The Iron<\/strong><\/h2>\n

Each 312+ is loaded with two custom US-made AP2622 1:7 input transformer recreations that precisely match the ratio, timbre and frequency response of the original input transformers with it\u2019s characteristic peak and four custom US-made quadfillar AP2503 output transformer replicas with steel laminations that ensure this unit sounds exactly like an old 312 card.<\/p>\n

The op-amps<\/strong><\/h2>\n

The heart of any 312 preamlifier it\u2019s the famous 2520 op-amp. The Stam 312+ features the new SA-25, a meticulously reversed engineered 13 transistor op-amp based on a Huntington 2520 from the early which can be overdriven thanks to the output fader control to add as much coloration as desired.<\/p>\n

Functionality<\/h2>\n

Line input to run your mixes through it, a 48V phantom power, reverse polarization, a pad switch (-20dB) and an output fader to saturate the circuit an obtain a ray of colors are all included. There is also an automated DI which automatically switches on when detected.<\/p>\n

Our Philosophy<\/strong><\/h2>\n

At Stam, we do many things differently, and one of them is that our ears are the ultimate decision maker. We spend thousands of hours listening to every component and circuit change despite science and engineering telling us that it should bear no difference in the tone of a unit. More frequently\u00a0than not our theoretical knowledge is proven wrong.<\/p>\n

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Technical Specs<\/h2>\n

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