
Page 3 © 2012-2020 Sonic Nuance Electronics
Additional Notes on Front Panel (Continued)
Foot switch: This will respond to toggling about once every three seconds. Faster toggle
rates will be !ltered out and ignored.
GND (push) switch: Unlike other products, the TDI uses a patented design allowing it to be
powered via the XLR jack even when the ground is lifted.
OUT jack: This is a bu"ered and transformer isolated copy of the signal on the IN Jack. It is
designed to provide superior performance to so called "true bypass" designs. This can drive
200 feet of cable with ease, and with transformer isolation, it helps remove the hum caused
by ground loops.
Powering the Unit
To avoid the transient audio "pop" when powering up or down the TDI, follow this rule:
make sure that what the TDI's XLR and 1/4" OUT jacks are connected to are muted or o! "rst.
For example, before powering on or o"the TDI when connected to the input of an
ampli!er, make sure the amp is muted or o" !rst. This way the turn on or o"transient
"pop" of the TDI (or any other equipment it is connected to for that matter) will be muted.
Similarly, if the TDI is to be powered via the XLR plug, make sure the channel the XLR is
connected to on the mixer is muted before connecting/disconnecting the XLR plug.
After powering up the TDI, it is recommended to wait 2-3 minutes before using the foot
switch. Due to the high input impedance of the bu"ers, it takes some time to allow internal
voltages to stabilize and make the switching as audibly quiet as possible.
Modes of Operation
The TDI can be in one of two modes: TUNING and PLAY modes. In TUNING mode, the
display shows the current note detected on the input jack (or C” if nothing is detected as
the tuning algorithm is cleared when !rst put in this mode or on power up. Once a note is
detected, the display will change accordingly and remain until another note is detected or
the mode is changed). Upon power up, the TDI will start in tuning mode for most situations.
In PLAY mode, the display indicates the letter P. The internal digital clock is slowed to a
minimum to avoid digital "hash" corrupting the analog signal. Getting rid of this hash is
especially important when using high gain ampli!ers. Also, unlike the competition, the
signal does not pass through a transistor switch which can cause unwanted distortion.
Tuning with the TDI
To engage the tuner, make sure the display does NOT show the letter P. When the tuner is
activated, both XLR and 1/4" OUT outputs are muted for silent tuning. (Note that this
could also be used to change instruments without bothering the soundman in live
situations.)
Pluck a single note at a time (you should mute the strings not being tuned) and the display
window will indicate the note that is being played. A dot in the lower right corner of the
display indicates the sharp (#) of the note. The display indicates the chromatic notes
detected in "mute mode" as shown in the table below:
Note A A# B C C# D D# E F F# G G#
Display AA.BCC.DD.EFF.GG.