Warm Audio WA12 MKII Classic 312-Style Analog Microphone Preamp

Liven up any source! Inspired by the API 312, the WA12 MKII pre delivers 71 dB of clear, warm gain with switchable impedance and a Melcor 1731-style op-amp.

If you are looking for a preamp to improve and shape your signal, you will most definitely love the Warm Audio WA12 MKII. The WA12 MKII is designed to transform plain instruments and vocals into exciting tone. If your mixes lack depth, struggle to sound alive, or are just missing that professional touch you've always wanted, there is a good chance the WA12 MKII is what you need.

The WA12 MKII is a completely discrete, high voltage, dual-transformer microphone preamplifier designed for high gain (+71dB), high headroom, low noise, and an exciting sonic performance -- great for all types of recording applications. A high-quality mic preamp is one of the most critical pieces needed to achieve the elusive 'larger than life' sound, and the WA12 MKII is more than capable of delivering.

The WA12 MKII is based around a discrete op-amp, the X731, which is our own reproduction of the vintage classic Melcor 1731, considered by some to be the warmer predecessor to the modern 2520-style op-amp. The X731 can achieve vibrant, clean and lifelike tones; but can also be driven into mild saturation at much higher gain levels. The effects can be subtle, but very pleasing to the ear. The WA12 MKII can also accept any discrete op-amp on the market which conforms to the +/-16v, 2520 pinout standard.


- Utilizes premium grade input and output USA CineMag transformers.
- 71db of Gain, fully discrete signal path.
- Utilizes a discrete 6-pin socketed 1731 style op-amp. Can be replaced read more with other 6-pin "2520 foot-print" op-amps for varying tone/flavor.
- TONE button – Switches the input impedance from 600 ohms to 150 ohms. Changes the tone of both the mic and HI-Z inputs.
- 2 Meg Ohm True HI-Z input on front panel. Sends instrument signal through entire circuit including both Cinemag Transformers and the discrete op-amp. Great for guitars, bass, keyboards and other instruments that have a 1/4" output jack.
- Output attenuation control (after the CineMag output transformer) allows for driving the preamp and transformers into saturation.
- LED Meter gain indication.
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- 20db pad.
- External power plug.
- Balanced outputs: XLR and 1/4"/TRS.
- 48 volt Phantom Power.
- Mic level balanced input: XLR.
Dimensions and Weight in Packaging
Shipping Weight: 6.75 lbs
Shipping Dimensions: 14 x 13 x 4 in
Manufacturer Part Number (MPN): WA12 MKII Black

For support or warranty questions, please contact the manufacturer:
Web: https://warmaudio.com/contact-support/

Reviewers gave this product an overall rating of 5 out of 5 stars. (2 ratings)
Submitted July 18, 2018 by Daiquan G in New York, NY
"Amazing api style pre for half the price."
Overall: 5 out of 5 stars
(see rating details)
Verified Customer zZounds has verified that this reviewer made a purchase from us.
I have collected a lot of analog pres overtime and collected pres ITB. There is a reason why analog is always the best option. This pre is probably the cleanest out of all the pres I have. When I push this units input gain there’s this nice sweet saturation that you can hear but the source material still maintains this clarity. This is great on everything. I prefer it on drums and guitars. The build is very solid. I find the orange color to be very attractive and it stands out from everything else In my rack. If you want quality at a price point that’s reachable here is a great preamp for you.
Musical Background:
I have been producing music and engineering in NYC for 8 years. I play keys and do a lot of analog synthesis.
Musical Style:
Rock, Hip-Hop, Jazz, Pop, Lofi Hop-Hop.
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