### Author:  [@Digital\_Larry](https://forum.foleysfinest.com/u/Digital_Larry)
#### Post date: [30 June 2021 16:52 UTC](https://forum.foleysfinest.com/t/how-to-2-add-an-analyzer/14/6 "2021-06-30T16:52:07Z")
In my processor:
```auto
foleys::MagicLevelSource* LFOLevel = nullptr;
```
In the constructor:
```auto
LFOLevel = magicState.createAndAddObject("LFOLevel");
```
This is in my prepareToPlay():
```auto
magicState.prepareToPlay(sampleRate, samplesPerBlock);
LFOLevel->setupSource(1, sampleRate, 500, 200);
```
And this is what it looks like:
There’s a white box with a green line on the bottom. I don’t see anything happening. It strikes me that there’s no connection to a specific signal… I’m not just using the block outputs.
Yeah, sorry… missing this part.
---
### Author:  [@daniel](https://forum.foleysfinest.com/u/daniel)
#### Post date: [30 June 2021 17:13 UTC](https://forum.foleysfinest.com/t/how-to-2-add-an-analyzer/14/7 "2021-06-30T17:13:46Z")
Glad you found it.
BTW. the simple bar is not particularly beautiful, a LookAndFeel interface to create different level meters is on the road map.
---
### Author:  [@Digital\_Larry](https://forum.foleysfinest.com/u/Digital_Larry)
#### Post date: [30 June 2021 18:11 UTC](https://forum.foleysfinest.com/t/how-to-2-add-an-analyzer/14/8 "2021-06-30T18:11:26Z")
I got it to work but it is only listening to the block output. How do I hook it to an internal signal in my program? In Faust I can put a bar graph readout in any signal line. If I leave it as created in PGM by default (a slider) then the slider moves as my LFO does its thing. So I just want to replace the slider with a meter.
---
### Author:  [@Digital\_Larry](https://forum.foleysfinest.com/u/Digital_Larry)
#### Post date: [30 June 2021 18:39 UTC](https://forum.foleysfinest.com/t/how-to-2-add-an-analyzer/14/9 "2021-06-30T18:39:39Z")
Another thing about the Faust code generator is that it creates processBlock() with \ also:
but if you add the line in the second one you’ll get a compilation error.
---
### Author:  [@daniel](https://forum.foleysfinest.com/u/daniel)
#### Post date: [30 June 2021 19:58 UTC](https://forum.foleysfinest.com/t/how-to-2-add-an-analyzer/14/10 "2021-06-30T19:58:05Z")
Thank you for the heads up. I will add a function that accepts an `juce::AudioBuffer&`.
As for the question about displaying a different signal, that is difficult. How would it know what to measure?
Normally you have the different commands and loops in the processBlock() so you can measure anywhere, but in this case you can only measure before and after the processBlock().
Is there an API to get information out from the faust dsp?
---
### Author:  [@Digital\_Larry](https://forum.foleysfinest.com/u/Digital_Larry)
#### Post date: [30 June 2021 20:11 UTC](https://forum.foleysfinest.com/t/how-to-2-add-an-analyzer/14/11 "2021-06-30T20:11:36Z")
Here’s how it’s apparently done in Faust generated C++.
```auto
FAUSTFLOAT fHbargraph1;
```
In buildUserInterface():
```auto
ui_interface->declare(&fHbargraph1, "01", "");
ui_interface->addHorizontalBargraph("LFO", &fHbargraph1, 0.0f, 1.0f);
```
Then, the variable is just part of the dsp “compute” function.
```auto
...
fHbargraph1 = FAUSTFLOAT(fRec18[0]);
float fTemp22 = ((fRec17[0] * fHbargraph1) + 1.0f);
...
```
Looks like some special case code generation?
```auto
#define FAUST_LIST_PASSIVES(p) \
p(HORIZONTALBARGRAPH, LFO, "[00]/LFO", fHbargraph1, 0.0, 0.0f, 1.0f, 0.0) \
p(HORIZONTALBARGRAPH, Level, "[00]Low/Level", fHbargraph0, 0.0, -80.0f, 1.0f, 0.0) \
p(HORIZONTALBARGRAPH, Level, "[01]Hi/Level", fHbargraph2, 0.0, -80.0f, 1.0f, 0.0) \
```
Anyway, it looks like things are arranged such that the UI has full visibility of the DSP’s internal details. For the level meter at least, we just need a single value, not a block of data.
I just need something that behaves like a slider but looks like a level meter.