Topic: "Weak" phantom power on Tascam DR-100?

[guyburns]

I'm in the market for a field recorder and have narrowed my sights to the PMD-611, H4N, and DR-100. I want to find out if users of the DR-100 have come across this problem reported on the Amazon listing for the DR-100 (second review by Lotus-Seven). This is what was said:

However, I've encountered a much more serious problem (for my use). So far, I've had problems when using the DR100's internal +48V phantom power with several sets of widely available phantom powered mics. I connected a pair medium-output (-70dBV/Pa) ribbon mics and was not surprised that the DR100 did not have enough gain. I then tried a set of "active ribbons" (with phantom powered internal amplifiers and found that everything worked fine if only one mic was connected, but connecting both mics caused a very audible (-30dB) high-pitched buzzing noise in both inputs. This only occurred when running on the fully charged internal Li-ion battery. When running on the PS-520 external power supply/charger, the noise disappeared, even with both mics connected. To me this indicates a weak +48V phantom supply. I tried another set of mics, a pair of very popular small diaphragm omni condensers and even running on the external power supply I had serious noise generated when both mics were drawing current from the DR100's phantom power source.

Please note that all of the mics I tried all work fine using any of my Mackie, SECK, Yamaha, True and Presonus mixers and preamps with absolutely no problems.

The reviewer goes on to say that he'll keep the DR-100, but will carry external mic preamps. As far as I'm concerned, if the phantom supply is sus, the DR-100 is out of the running.

Has anyone encountered the problem of the DR-100 generating audible hum when two phantom microphones are being used? It is likely to be a current-draw problem, and may only show up with microphones that draw a certain amount of current.

The 48 volt supply of the PMD 661 has a maximum current draw of 10 mA. I couldn't find the maximum current specs for the DR-100, but assume it would be similar. If anyone has the technical know-how, and has a DR-100, putting a 22k resistor across each of the 48 volt supplies lines may induce the problem (a combined current of about 5 mA). Or simply connect two 48 volt microphones.

[flintstone]

When I took a look at the DR-100, I found I could power two Rode NT-1A mics for about 3.5 hours, starting with the DR-100's internal Li-Ion battery at full charge.  That said, I wouldn't recommend the DR-100 for quiet subjects because it has a relatively noisy preamp (similar to the DR-1, better than the DR-2D).  I also had problems getting a range of SDHC cards to work properly.  I often had to format them on a PC first before the DR-100 would recognize them.

I think the Marantz PMD661 or the Fostex FR-2LE would be a better choice for a two channel all-in-one recording solution (about $600).  Or step up to six channels of phantom power in the Tascam DR-680, about $800.

Flintstone

[guyburns]

Thanks for the responses. I'm reasonably confident that the PMD 611 is the superior unit of the three I mentioned, I just want to make sure the DR-100 has the power supply problem alluded to, so that I can safely cross it off. I must say I am surprised that Tascam would allow a unit with a noisy supply to be released.

If anyone has access to the DR-100 and an oscilloscope, could they confirm the supply is inherently noisy?