Re: [AH] Using DI BOX with synths?

From Ivan Schwartz
Sent Tue, Jun 19th 2018, 02:31

Only active DI use phantom power; passive ones with transformers do not =
need phantom.  The active circuits in a DI typically do not provide any =
gain.

Phantom power is current limited (thus the higher voltage) so there is =
little power available for a real preamp design.  Phantom powered mic =
are usually putting out a mic level signal, not line level.  A =
500-series rack power supply has much more current available, and the =
bipolar power supply design allows for plenty of headroom.

The big issue I have using a DI for synths is that a typical DI is =
designed to drop the signal to mic level, and then you use a mic preamp =
to add gain.  This is not an ideal situation in terms of gain staging =
and optimizing signal to noise ratio.  That is why devices like the =
SynthDriver were designed.

Ivan


> OnJune 13, 2018 at 8:16:52 PM, Brian Willoughby via analogue =
<xxxxxxxx@xxxxxxxxx.xxx> wrote:
>=20
> Considering that DI products are almost always used in a situation =
where phantom power is available, and potentially even where wall power =
outlets might be in short supply, it makes sense that DI designers would =
include the option to power everything from phantom power.
>=20
> In addition, since phantom power is (supposed to be) 48V, that=E2=80=99s=
 a lot more power for a preamp than, say, the +/-16V of 500 Series =
modules.