Here is what I have experienced in setting up each of these 3 ways to use the POD HD 500 and the DT25 amp.

You do have to set patches up differently for each of the 3 ways.

1. Direct to mixer - XLR

2. L6 Link to DT25

3. 1/4 Amp (which is really using the POD like an FX unit only)

(You will have 3 different versions of each patch).

It is very managable because there are so many presets... so not a problem, but it is important to have all 3.

Using the HD500 Edit software there are 5 screens.  FX  -  Amps  -  Mixer  -  Controllers  - Setlist

The AMP screen is the ONLY one that needs changing for the 3 different patch types.

1. Direct XLR to mixer - This one is pretty straightforward.

Choose an Amp model -  (NOT Amp models with PRE at the end of them) and choose a Cabinet Setting).

Tweak the settings for: drive, bass, cut, treble, presence, channel volume... also E. R. and mic settings for the amp cab.

You can also modify the Class; Topology, and Mode.

Amp Parameter knobs are Master, Sag, Hum, Bias, Bias X

--modifying the "Amp Parameter" knobs will be lost when creating the replica patches for "L6 Link" and "1/4 Amp IN" only settings.

Save the patch then recall it to a DIFFERENT slot in the software. (1a, 1b, etc.)

2. L6 Link to DT25

First -

Make a screen shot of the AMP screen from patch type "1. (Direct XLR to mixer)".

make sure you have double-clicked to select the NEW slot where you copied the patch to).

NOW - select the Amp Model you had before except this time it WILL have the word PRE at the end.

EXAMPLE: "Class A30 TB" will now be "Class A30 TB PRE".

The "Amp Parameter" knobs (Master, Sag, Hum, Bias, Bias X) will be disappear and be replaced by a silver bar.

Also... drive, bass, cut, treble, presence, channel volume will change to a default setting based on that amp model.

Use the screen shot and reset them to the same settings as your previously created "Direct XLR to mixer" patch.

Save the patch to your computer with a NEW name (I put the word PRE in front of mine so the rest of the name matches the "Direct XLR to mixer" patch)

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Make sure you have set this system parameter 

L6 LINK:CONTROL >>> AMP 1 option to "AMP A (CH1)."

***

Choosing the PRE amp setting now makes the DT25 sync to the amp settings for your chosen configuration.

and the preamp settings in your POD HD 500 are being used instead of the preamp settings in your amp.

(using the NON PRE setting is double preamping and very loud but also not a matched sound to your previous patch and can damage the speaker... among other things)

3. "1/4 output to Amp IN"

Really this is just using your POD HD 500 like an FX unit

maybe you love your amp and don't want to change it's tone

but you would like to use the POD HD effects only.

This one is easy ! 

Recall your first patch type (Direct XLR to mixer) to a NEW location in the HD edit software.

go to the AMPS page and turn off the amp. (one click on the circular button)

save it with a new name. (I usually put FX in front of the existing name).

Now you can plug a guitar cable from 1/4 out mono: to the 1/4 guitar input on your amp.

this keeps your amps tone but let's you use the effect pedals built into the POD HD 500.

if you use the first two patch types (the ones with amp and preamp) it overdrives your input and is incredibly loud.

definitely can damage your amp; speaker; hearing, etc.

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So... in summary:  you should have 3 patches named something like this.

Favorite Tone                      (direct XLR to mixer)

PRE Favorite Tone                     (L6 LINK)

FX Favorite Tone                     (1/4 input to AMP)

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