Imagine 10 or 15 years ago if someone told you that they were going to take ribbon mics on tour to put in front of guitar amps onstage; the thought would have been absurd from every angle. They’re too delicate to survive the rigors of the road, they can’t handle the SPL, their polar pattern will promote pickup of unwanted crowd sounds at the back of the mic, they’re too expensive to break… All of these “disqualifiers” made ribbon mics just plain wrong for live sound.
The CADLive with D82 is a passive ribbon mic that aims to bring studio-quality sound to live performance, at a very attractive price.
Built to Perform
The D82 features some clever new design work from the CAD engineers. First, the ribbon element is designed from the ground up to be more durable. This is achieved by making the element significantly thicker than usual. Classic RCA microphones and newer AEA models feature ribbons as thin as 1.8 microns and never go much thicker than 2. The Royer 121 live edition uses a 4-micron ribbon. The D82 doubles that with an 8-micron design. I would have guessed that a thick ribbon would compromise top-end detail, but the D82 does not seem to struggle in that department at all. It can also handle more SPL than possibly any other ribbon mic available.
High SPL handling is achieved, in part, by the thick ribbon, but bolstered by a dual-stage blast guard built into the capsule assembly. The capsule is further fortified by a dual-layer mesh in the outer basket. Care was taken to ensure that the ribbon is centered inside of this basket providing identical sound from the front and rear. This is key to producing proper imaging when using a mic for any application that depends on a true figure-8 polar pattern.
The other key factor, when considering the production of a modern ribbon mic, is to keep the noise floor down. Considering the low output of the ribbon capsule, some newer designs take advantage of active electronics. The D82 doesn’t use this approach, so don’t apply phantom power to this mic. Due to the low impedance of the ribbon capsule, however, a transformer is necessary to match the impedance of the mic’s output to the mic preamp. Rather than going with a prefabbed design, the CAD engineers built a custom transformer designed for maximum sensitivity. The job was done well, because I was often surprised when I would set a level for this mic. I usually had the gain set far lower than I would when using a typical passive ribbon mic. This transformer also seemed to provide clean signal with very low noise.
CADLive Series’ D80 was clearly designed for miking guitar amps, so I started there. The D82’s flat design seemed to lend itself to placement close to the grille of the amp, so I placed the mic dead center on the speaker, a few inches from the grille on a 2×12 tube combo. The max SPL of 140 dB suggested it should be able to handle that placement, but I played it conservative on the amp volume for starters. Playing some clean tones and listening through headphones, it was not surprising to find the sound to be overwhelmingly bassy with no clear highs. Compared to other microphone types, ribbons are far more prone to exhibiting proximity effect, or the over-exaggeration of low frequencies when the mic is very close to the sound source.
Despite that, the mic handled the SPL well, so I had two choices. Either I could play with the placement and try to find a more balanced tone, or I could bring in a second mic to add some detail in the top end, and embrace the giant bottom end that this mic was producing. I chose the former and quickly realized that even the slightest changes to the placement of this mic had a profound impact on the overall sound.
I wound up backing the mic up about three feet, still aimed dead center at the cone. The tone started coming together and the top end started to keep up with the bass a bit better. The low end was still a bit out of control. I had been using the mic with the included clip, and it occurred to me that maybe the bass was just resonating through the floor and up through the stand. I suspended the mic in a universal shock-mount, which made a difference. The proximity effect was still something to consider, but now I could bring the mic about a foot away from the amp and the tone was excellent. The detail in the top end was very clear and honest without being harsh. I put my headphones on and off, and the top end of the amp and the room sounded nearly the same. The only real difference was that there was an in-your-face quality to the bottom end. It wasn’t over the top, just nicely forward.
I moved the mic a bit closer to the amp for an overdub of a slightly distorted arpeggio of higher notes. There was nothing below the 9th fret, so there was no real chance of the bass getting out of control. I had the mic just off the center of the speaker about 4 inches from the grille and the sound was perfect for cutting through the mix. I had a tube condenser up as well, but it was too brash to be useful. The D82 had the perfect balance of detail in the top end, midrange bite, and the warm tone of the cabinet in the bottom.
I moved over to a small, cranked combo, with a bit of a Brian May-like nasally tone. In this case, the proximity effect hit hard and I wound up finding a sweet spot about 2 feet away from the amp, just off center. As I was moving the mic around, I found that rotating the mic even the smallest amount radically changed the overall sound. Placing the mic slightly off-axis but turned a few degrees toward the center of the speaker, a great flavor appeared, again, sounding like a slightly bottom-heavier version of the truth. The sound was tight and the mic added a little bit of a thump with the pick attack to accentuate the notes.
Given the heavy bass build-up of the mic, I thought I’d try just exploiting that, moving it close to the amp and bringing in a bright dynamic to pair with it. This combo worked really well for chugging, down-tuned, palm-muted chords. The ability to balance the ratio of thud to bite after the fact was useful in mixing. This pairing was also really useful for riffy stomps in the style of Rage Against the Machine or Zeppelin. The D82 provided next to nothing in terms of top end in that placement, so without even needing to EQ, the top and bottom were crossed over between the two mics.
M/S, Strings and More
I moved on to acoustic guitar and set up the mic pointed near where the neck meets the body, about 6 inches from the guitar. The sound was much too bass-heavy, so I backed it off to about 10 inches and started moving further up the neck. Somewhere around the 12th fret, the sound seemed pretty balanced and sounded much like the guitar itself. There wasn’t much detail on the pick attack, so I tried rotating the mic in the mount and cheating it toward the sound hole where the pick was hitting the strings, but could never quite find a spot where that detail came to life without the bass taking over.
From that position, I could record with good overall sound if I rolled off a lot of the bass. A better sound was achieved pointing straight at the neck, and adding a condenser to grab the picking sounds. With those two mics already on hand, I again played with rotation of the mic and found that the off-axis rejection was superb, so it seemed that the D82 would be a good “side” mic. Indeed it was, and the stereo image that it produced was very wide and clear as the mic caught all of the details of the room and the reflections.
The D82 is a very useful mic and stands on its own. It doesn’t really sound like the Royer or Blue ribbon mics, which seem to present a little more top end. There’s little comparison to vintage ribbon mics either, as it is rugged, durable, quiet, and still has a different personality than the older designs. It’s welcome in the studio, and I look forward to using it again. I didn’t get a chance to use it onstage, but with the build quality and high SPL handling, I wouldn’t be worried to take it on the road. Being very mindful of placement and pairing it with a shock-mount seem to be important concerns, but if those considerations can be met, this mic won’t disappoint.
Brandon T. Hickey is an audio pro and rabid Blackhawks fan.
COMPANY: CAD Audio
PROS: Ribbon mic sound in a light, rugged package.
CONS: No shock-mount provided.
A figure-of-8 polar pattern is not just double cardioid. The lobes are more directional than even the hypercardioid pattern and off-axis rejection is unparalleled. When two amps must share one iso booth, try setting up the cabinets in a right angle with their speakers axis’ aimed at the same space, but 90˚ perpendicular to one another. Set up two ribbon mics at the convergence point of the speakers’ energy, one pointed at each amp, with each mic’s null point aligned with the opposite amp. You’ll get great on-axis sound, with very little bleed.