Mixer mic level output into the newer Lectro transmitters

To the Group:
We had a reality show mixer with a problem using new UM400a and old
UM400 transmitters together with mic level outputs coming out of a
Sound Devices mixer. The servo input had much more gain (+20 dB) than
the older input and the difference was causing additional setup time
getting levels set and confusion for the crew. We have a new mic level
cable, the MC41, that matches the gains of the two different
transmitters. Here's the FAQ #115 and instructions on how to roll your
own.

Problem: I have many UM400 and UM400a transmitters on a reality show.
I'm coming out all my mixers at mic level into either the UM400 or the
UM400a transmitters using a MC40 cable. The gain settings are
confusing. What can I do to make this easier?

Resolution: The mic level input on the UM400a has the new servo input
with much more gain for low impedance signals than the UM400 with the
older input. The increased gain improves performance with dynamic
microphones. However, switching back and forth between the UM400 and
UM400a transmitters will require constant readjustment of the gain
setting if you are using the MC40 cable. To make life simpler we have
a MC41 cable that will work with either transmitter type and matches
the gain to within a few decibels. If you want to build your own, the
wiring of the TA5F is as follows:

pin 1 is ground
pin 2 N/C
pin 3 to a 3k resistor in series with the mic level wire.
pin 4 jumped to pin 1 (sets the servo bias to zero)
pin 5 N/C

This places resistance in the audio line and reduces the input to the
UM400 by only a few decibels but reduces the UM400a by 20 dB and
matches them very closely. The MC41 can be used with all the servo
bias mics such as the SMa, SMQa, SMDa, UM400a, UM450, and LMa. It will
also work well with any of the older style transmitters.

Best Regards,
Larry Fisher
Lectrosonics

On Nov 27, 8:47 am, Larry Fisher wrote:
> To the Group:
> We had a reality show mixer with a problem using new UM400a and old
> UM400 transmitters together with mic level outputs coming out of a
> Sound Devices mixer. The servo input had much more gain (+20 dB) than
> the older input and the difference was causing additional setup time
> getting levels set and confusion for the crew. We have a new mic level
> cable, the MC41, that matches the gains of the two different
> transmitters. Here's the FAQ #115 and instructions on how to roll your
> own.
>
> Problem: I have many UM400 and UM400a transmitters on a reality show.
> I'm coming out all my mixers at mic level into either the UM400 or the
> UM400a transmitters using a MC40 cable. The gain settings are
> confusing. What can I do to make this easier?
>
> Resolution: The mic level input on the UM400a has the new servo input
> with much more gain for low impedance signals than the UM400 with the
> older input. The increased gain improves performance with dynamic
> microphones. However, switching back and forth between the UM400 and
> UM400a transmitters will require constant readjustment of the gain
> setting if you are using the MC40 cable. To make life simpler we have
> a MC41 cable that will work with either transmitter type and matches
> the gain to within a few decibels. If you want to build your own, the
> wiring of the TA5F is as follows:
>
> pin 1 is ground
> pin 2 N/C
> pin 3 to a 3k resistor in series with the mic level wire.
> pin 4 jumped to pin 1 (sets the servo bias to zero)
> pin 5 N/C
>
> This places resistance in the audio line and reduces the input to the
> UM400 by only a few decibels but reduces the UM400a by 20 dB and
> matches them very closely. The MC41 can be used with all the servo
> bias mics such as the SMa, SMQa, SMDa, UM400a, UM450, and LMa. It will
> also work well with any of the older style transmitters.
>
> Best Regards,
> Larry Fisher
> Lectrosonics

Is line level different as well?