DM4800 Phantom Power Failure!

[warpdriveprod]

I set up my DM4800 to record drum tracks which consists of 9 sE Eletronics condenser mics (7 large diaphram and 2 small with internal FET circuitry) using the board's internal phantom power. All went well during the calibration of gain pads-got all the levels set just fine. Played drums through the system for about 20 mins and it was all good. However a few hours later when I began tracking drums, I had no mic signals coming into the board.

I tested channel #1 with a dynamic Shure SM-58 (with the internal phantom power disabled) and it worked just fine. Next I grabbed my Rolls PB23 phantom power adaptor (supply) and patched it between a condenser mic and the channel #1 input (again, internal phantom power disabled) and it worked just fine. These tests lead me to believe that somehow the phantom power supply inside my DM4800 has failed,

Has anyone else experienced this problem? What can be done to bring my phantom power back up?

 

[captdan]

Have you tested all of the phantom inputs? If memory serves (and it often doesn't), the preamps (on the DM4800) are in 6 banks of 4. In otherwords, Inputs 1 through 4 are part of one bank, 5 through 8 another, etc. So, if #1's .48 volt power fails, 2,3 & 4 could go down with it. So, it might be worth checking Inputs 20 thru 24 to see if phantom is operational on those.

Of course, there's always the possibility (again) of a detached internal cable or connection. Beyond that, I wouldn't know what else to suggest other than another trip to Tascam Repair Central.

CaptDan

 

[nflyte]

I also lost input signal on my phantom power in 1 to 4. Even when phantom is of there was no signal. I managed to get back my signal now without phantom and am going to retry my condensor mics. Having phantom in banks of 4 is a bad idea and should be seperate for all channel inputs. If you are only using 2 condensors you lose 2 channels in that bank that could be used for dynamic mics. I'm going to look into external phantom power units for separate channels.

 

[nflyte]

there are different points to look at with dynamic and phantom power but on the most part it is safe to use phantom power on most dynamic mics but check with the mic specs to see if it is safe to use phantom power for your mic. Here's a link to SOS on phantom power. https://www.soundonsound.com/sound-advice/q-phantom-power-on-dynamics

 

[nflyte]

Question:
I have an 8 channel mixer which sends phantom power to all mic inputs when the phantom is activated. I would like to run a SM81 and a SM58 through this mixer in a live performance situation. My question is, if I enable the phantom power on the mixer for the SM81, will it affect the operation of the SM58?

Answer:

No. Any dynamic microphone with a low impedance balanced output, like the SM58, is not affected by phantom power.
Phantom Power will not damage a professional dynamic microphone.

From the Shure website