The RM-5C is a ribbon mic with a sound all its own.
Designed by Silvia Classics and branded and distributed by Telefunken USA, the RM-5C cardioid ribbon microphone ($1,495) is a modern take on the classic shape of the RCA BK-5. The RM-5C has a striking, textured black finish and art deco grille housing, with arrows pointing to the business end to indicate that this is a front-address mic. (Anyone familiar with the RCA BK-5 will not be surprised by this.) However, the fact that it isn't a side-address mic with a figure-8 pattern is only one of the ways in which the RM-5C differs from your typical ribbon transducer.
I used the RM-5C beside four other ribbon microphones as well as a few dynamic and condenser mics. I auditioned it on vocals, electric and acoustic guitar, electric and upright bass, saxophone, accordion, and in various positions on drums. The mic comes with a leatherette pouch and large, spider shockmount, all within a wooden case.
Compared with other ribbon microphones I own, the RM-5C has unique, unribbon-like characteristics, such as an aggressive upper midrange and a less substantial low end. Because my RCA 77DX can be switched into cardioid mode, I did a number of tests comparing the directionality and timbre of the two mics to get my bearings, though it's not surprising that they sounded completely different. The RM-5C achieves a tighter directionality than the 77DX, picking up significantly less ambient room sound when close to the source. Additionally, the two mics have complementary frequency responses, with the 77DX accentuating the lows and low mids and the RM-5C heavy on the high mids and highs.
The differences were just as noticeable when I compared the RM-5C with Royer and Coles ribbon mics, both of which offer only figure-8 patterns. Because they had such different tonal characteristics, I often found myself leaving both the RM-5C and my reference ribbon mic up and blending the two for the best sound. This worked really well on an electric bass cabinet, where the RM-5C accentuated the midrange of the picked bass while the other mic filled in the low end nicely.
The standout application was on upright bass, where the RM-5C sounded amazing. Situated about a foot and a half in front and a couple of inches above the bridge, the mic gave me a full, clear, rich tone, without the boomy bottom of many other mics in this position. The balance between the woody thump and the articulation of the fingerboard was about as good as one mic alone can capture.
The RM-5C also sounded good on acoustic guitar. I placed the mic about two feet away from the instrument, pointing between the 12th fret and the sound hole. Again, the combination of woody tone and pick articulation was very balanced. However, on a different guitar on a different day, I needed to blend the RM-5C with a small-diaphragm pencil condenser to fill out the sound. Likewise, on male vocals (and similarly on piano) the RM-5C felt a tad thin, but when blended with another, beefier mic, it gave me good definition and presence. As for electric guitar, I got excellent results using the RM-5C on small, tube combo amps, whereas on louder rock rigs, the mic imparted an extra fuzziness I didn't much care for.
On reeds, I got mixed results. On alto saxophone, the RM-5C didn't fare well: there was a nasal quality to the mic that was unflattering to the instrument's tone, as if I had cranked up 1,200 Hz on an EQ. I liked the RM-5C quite a bit on accordion, though; it really grabbed the reediness and growl of the instrument in a pleasing way.
The two best drum applications I found for the RM-5C were as a secondary bass drum mic to add some presence (positioned a few feet back and with a pop filter, of course), and as a room mic pointed away from the kit at the back wall. In general I wasn't happy about the way the RM-5C picked up the metal of the kit: it gave the cymbals and hi-hats an aggressive midrange that needed some subtractive EQ in the area of 1 to 3 kHz.
A Unique Voice
Although the RM-5C isn't good at everything — few mics are — the things that it is good at make it arguably worth having in your collection. The upright bass sound I captured with it alone makes me want to keep an RM-5C around.
The RM-5C wouldn't be my first choice for a single ribbon mic to own, especially at an introductory price of $1,495, because it's not quite as utilitarian as other ribbon mics. Nonetheless, it has a very interesting character, and I was able to get some great sounds with it. If variety in acoustic flavors is what you're after, give the RM-5C a taste.
Value (1 through 5): 4