CAD 177 & 179 power issues

omtayslick

New member
From a Sound on Sound review:

"The M177 and M179 require phantom power between 24V and 48V (although some CAD literature suggests they can accommodate 52V supplies as well), but with a whopping 8mA supply current! This is well over twice what most other condenser mics require. The Sennheiser MKH80 and AKG C414 require only 3mA and the Neumann U87 a mere 0.8mA, for example. High supply current can cause problems in badly designed equipment, or where poor-quality mic cables are being used, because of voltage losses. If a lot of current is drawn from a poor phantom power supply, its output voltage is likely to sag below the nominal 48V, making it more likely that the microphones will lack headroom and suffer transient distortion. It is also possible that, even if the CAD mics don't suffer as the phantom voltage droops, other mics powered from the same supply may be affected — something to watch out for when using a full complement of mics on a mixer with a small power supply. Also, the inherent resistance of mic cables means that the greater the current flowing, the more phantom voltage is lost in the cable itself, with the same end results.

Although I didn't experience any obvious problems testing these mics with a range of mic preamps with internal phantom supplies, I was careful to use good-quality mic cables and to keep cable runs as short as possible. In general I would be very wary of using large numbers of high-current mics together, powered from the same supply, or at the ends of long cable runs."



Is this a real cause for concern? Howzabout if you're using something like a DMP3, and want to run 2 mics at once? Anyone own one of these and can enlighten me? Other than that, the reviewer loved the mics.
 
Yea, I think they're good mics, but the reviewer is pretty much spot-on. They are kind of high-maintainance in terms of the phantom power issue. You might want to think twice before plugging it and another condenser in to the dmp3 at the same time -- unless it's one that isn't particularly greedy with the phantom (ie -- an electret or similar).
 
When I was at Summer NAMM, CAD had these two mics plugged into one Behringer mixer and they seemed to work just fine. I think running two at the same time on any decent pre (other than the Audio Buddy which has limited phantom power) would be ok. You can always put the leads of a volt meter across pins 2 & 1, or 3 & 1 of the mic cable connecter and measure the PP voltage while the mic in question is connected to the other channel.
 
Back
Top