We Test Four Warm Audio Microphones And Compare Them With The Original Mics - Can You Tell The Difference?

October 29, 2018 Audrey Martinovich

Warm Audio is a gear manufacturer that strives to emulate the sound quality of vintage high-end gear, but with a much smaller price tag. I wanted to see how some of their microphones compared to their vintage counterparts.

The microphones I tested were:

WA-87 FET Condenser Microphone, $599

Neumann U87 Ai on the left and Warm Audio WA-87 on the right

Launched in 2016, this mic’s circuit design is based on the classic U87 from 1967. I’ll be comparing this mic to my Neumann U87 Ai. This version of the U87 was first introduced in 1986 with updated circuitry to allow for more headroom. Both the WA-87 and U87 Ai feature a dual-backplate dual-diaphragm capsule. The U87 Ai costs about $3,200 new.

WA-14 Condenser Microphone, $499

AKG C414 EB P48 on the left and Warm Audio WA-14 on the right

Based on the AKG C 414 of 1971, the Warm Audio WA-14 debuted in 2017 with mostly brass components. The WA-14 capsule is modeled after the CK-12 capsule that debuted in 1953 and was used in the first versions of the C 414 and C 414 EB. The AKG C 414 EB P48 that I will be using in comparison first came out in 1980 and likely has a nylon capsule, although some early P48s are known to have a brass capsule. The newest version of the C414 is the XLII and can be found for $1,100.

WA-47 Tube Condenser Microphone, $899

Warm Audio WA-47 on the left and Peluso 22 47 LEon the right

In 2018 Warm Audio released the WA-47. The WA-47 is a 9 multi-pattern vacuum tube mic and attempts to recreate the popular k47 capsule design of the late 1960’s. The high end version I am comparing it to is a Peluso 22 47 LE. The 22 47 LE features a true vintage German EF-12 steel tube manufactured between the 1940s and 1960s. The WA-47 employs a modern Slovak Republic JJ 5751 tube. In addition to the difference in tubes, the WA-47’s capsule is single-backplate and the 22 47 LE has a dual-backplate capsule. You can find Peluso’s version of the 47 for about $3000.

WA-47jr FET Condenser Microphone, $299

Warm Audio WA-47jr on the left an Peluso 22 47 LE on the right.

Also launched in 2018, the WA-47jr, is an FET transformerless version of the 47. Affectionately known as the “son” of the WA-47, this mic operates sans tube power supply. At the studio, we have two Peluso 22 47 LEs, so I set up our second one to compare to the WA-47jr. The Jr’s capsule is a recreation of the original single-backplate k47 capsule.

The Set Up

To compare the Warm Audio mics with the vintage versions, I set up each of the mics on a source with its counterpart as a coincident pair. All of the microphones were set with no pad, no HPF, and all in cardioid except for the 87’s which were both set to bidirectional. I ran all of the mics through Ampria mic pres and set each pre to a similar output across all mics.

The Sources

Lucky for me there is no shortage of talent in Madison, Wisconsin, where my studio is located. Four musicians stopped by to play a bit and let me experiment: Bryan Drewyor, Sarah Pray of indie folk band Carrellee, Kaia Kalise, and Sam Ness.

All four are wonderful singers and songwriters; two played guitar and sang for this test and two played piano and also sang. I chose to skip the pop filters for the vocal mics to see if one would be more prone to plosives than the others.

Recording The Samples

While setting the preamps, there was an interesting difference in output between the U87 Ai and WA-87. I had to boost the WA-87 by about 12 dB to get the output to match the U87 Ai. My theory is that this is because the U87 Ai has about 10 dB higher output than the original U87, and since the WA-87 is modeled after the original, we see that difference in output reflected when comparing it to the U87 Ai.

After the session, I trimmed the beginnings and ends of each artist’s original song then used clip gain to even out volumes so that I could get the best A/B comparison possible.

Which One Do You Prefer?

Below are each of the samples from Bryan Drewyor, Sarah Pray, Kaia Kalise, and Sam Ness. Rather than tell you which recording has been made with which microphone, we are presenting the examples in a blind comparison. Listen to each of the pairs of examples and then vote for the example you prefer. You are NOT trying to guess which microphone is which.