Warm Audio WA-47 Tube Microphone Review -Best Mic for Vocals Under $1000?

Since Warm Audio has stepped into the pro audio “ring”, they have made some serious ripples in the realm of vintage reproduction recording gear. I must say I was very intrigued when I first saw this mic. The Warm Audio WA-47 is a modern take on a microphone originally made by George Neumann in Berlin, Germany between the years of 1949 and 1965. The mic employed a tube design; early Neumann U-47s used the M-7 capsule, which was then replaced by the K-47 from 1958. Units produced before 1950 were distributed by Telefunken and bear the Telefunken logo.

The U-47 is one of the most famous microphones ever produced, used by The Beatles, Tony Bennett, Ella Fitzgerald, Louis Armstrong, Bing Crosby, and Frank Sinatra even owned his own. Original U-47’s can go for as much as $35,000 at the time of writing.

When I first saw Warm’s version, I was admittedly weary. A mic of that price and caliber for under $1000? It has to be a sham, right? It took me way too long to bite the bullet, but I finally picked up one. Wow – I was speechless. I was seriously impressed. I have had the pleasure of using an original once – a long time ago, and I would be lying if I could say they sound close. I just can’t remember that long ago, and hand built microphones that are that old will almost all sound different from each other. They’ve gone through aging (think smoke filled studios), modifications and servicing. I have also had the opportunity to try a few other U-47 clones. They are all different in their own right. The WA-47 is an awesome mic. I don’t know that you can find a solidly built tube microphone that performs and sounds this great for under $1000.

This mic emulates that classic sound, not with digital tricks but with solid construction and top notch quality parts and design. One of the awesome benefits of tube mics are the way they soften and handle sibilance, and the Warm Audio WA-47 does a great job of that. Sibilance is the nasty “sssss” or hissing that can come through in a recording. A hissing sound is created in a group of words through the repetition of ‘s’ sounds. 

I am a male baritone/tenor and I love what this mic does with my voice. Now, that’s not saying that it won’t be great on other ranges of vocals. It was also extremely flattering on my teenage daughter who is in the alto range.

The U-47 is known primarily as a vocal mic but also does great on a multitude of instruments. I used it in a session on acoustic guitar and it performed quite admirably. It ran through a Focusrite ISA preamp channel, and did not take long to locate the sweet spot on a Martin 000 acoustic guitar. I opted for placement roughly 14 inches away aimed at where the neck meets the body, slightly angled out, away from the sound hole. I used it in omni to pick up a bit more room sound, the room is treated well and has excellent levels of absorption and diffusion. The sound was warm and open, not lacking anything in the sonic spectrum. I was able to place it in the mix with no EQ and only a slight touch of compression, maybe a db or two.

All the time of recording I kept thinking “I wish I had access to a microphone of this caliper and price earlier in my career”. A great sounding tube microphone can help flatter the sounds you’re working with, often making it easier or less frustrating to achieve that sound you’re hearing in your head.

The mic is packaged extremely well and includes the power supply, shock mount, a 5 meter (roughly 15 foot) 7 pin high quality cable, a wooden presentation box and extra elastic bands for the shock mount. The construction feels heavy and sturdy like a quality product should. The only accessory not included is a separate “flight case” that carries not only the microphone, but the power supply, cables and shock mount. It can be had for an additional $99.00. The power supply has 9 different selectable polar patterns including cardioid, omni, figure of eight and everything in-between. This is quite a bit more versatile than the original that only had 2 selectable patterns, carded and omni.

In 1957, Neumann began to offer the U-48. The big difference was that the microphone dropped the omni position and offered cardioid and figure of 8 instead. On the Warm WA-47, I personally like the polar pattern that is one click to the right of cardioid. It does a great job of “focusing in” a little more tightly on my vocals.

Microphone Competition

As I said above, I really wish I had access to a mic this awesome that is this affordable. I think Most of Warm Audio’s competition in this price range is mainly from itself. Since the launch of the Warm Audio WA-47, Warm has gone on to make “clones” of the holy grail of microphones. They currently have their versions of the Telefunken ELA M251, Neumann U67, AKG C12, Neumann U87, AKG C414, Neumann U47 FET and the Sony C800. With the acceptation of their version of the Sony C800 ($1199), all the other mics are under $1000!

I honestly can’t wait to get my hands on Warm’s WA-CX12 to give it a spin (AKG C12). The next closest competition in a tube mic would be the venerable Mojave MA-300. Telefunken also makes the TF-29 tube microphone for $1299, and I have not yet had the opportunity to try or review it. The Mojave MA-300 Retails at $1399 and is a phenomenal microphone (I will review in another post), but is also $400 more than the Warm WA-47.

I think Warm Audio has a champ on their hands with this offering. And I don’t think you can go wrong here, this is a lot of mic for the price. Check out my other post on where to buy gear, at this time you can even get them used at Guitar Center for under $700.00 or even better, brand new at Zzounds paint it off over 4 or 6 months with no credit check! Make sure you have a sturdy mic stand and get recording – you won’t be disappointed!

From Warm Audio:

The Warm Audio WA-47 features a gold-sputtered, large, dual-diaphragm, dual-backplate K47-style capsule. The capsule in the WA-47 captures exceptional detail throughout the frequency curve, delivering professional studio sound. Moving down from the capsule, the WA-47 features a premium 5751 vacuum tube that creates extra warmth to achieve that signature analog tone. Completing the circuit is a custom-wound TAB-Funkenwerk (AMI) USA output transformer. The output transformer pushes a wide signal with incredible detail captured by the capsule, delivering authentic analog sound. The WA-47 uses premium WIMA, Solen French, and polystyrene capacitors throughout the circuit allowing ideal signal transfer for optimal performance. Our meticulous R&D process allowed us to dial in a true-to-original output level and frequency response that matches the performance expectations of world-class audio engineers and recording facilities.

Technical Specifications

• Custom K47-Style Capsule Recreation
• Capsule Makeup: Gold Sputtered, Dual Large Diaphragm, Dual-Backplate, 6 Microns NOS Mylar (PET Film)
• TAB-Funkenwerk (AMI) USA Output Transformer
• Premium 5751 Vacuum Tube
• Wima, Solen French, And Polystyrene Capacitors
• Self-Noise: 11dBA
• Polar Patterns: 9 Patterns – Cardioid, Omni, Figure-Of-Eight + 6 Mixed Patterns
• Dynamic Range: 130dBA
• Maximum SPL: 140dB (<0.5% THD)
• Frequency Range: 20 Hz~20 KHz
• Output Impedance: 200 ohms
• Rated Load Impedance: ≥2kOhms
• S/N Ratio: 82dBA
• Equivalent Noise: 10dBA (IEC651)
• Gotham 5 Meter GAC-7, 7-Pin Tube Microphone Cable
• Total Weight – 9 Lbs
• Mic Diameter: 60mm
• Mic Length: 254mm
• Includes: Microphone, Wood Box, Power Supply Unit, Shockmount, Gotham 7 Pin GAC-7 Cable, IEC Power Cable
• Retail Price $949.00

I will mention that the links above are affiliate links, meaning that at no additional cost to you, I will receive a commission if you click through and make a purchase. 

Optional Flight Case $99.00