Merge branch 'master' of ssh://code.hfbk.net:4242/sdiy/mami

README.md

@@ -36,26 +36,39 @@ Here an example 8x8 setup consisting of 4 Input tiles, 4 Output tiles and 16 Til
 
 The Input Tile has two 3.5mm Mono Input Jacks and two (On)-Off-On Switches that allows muting individual inputs (or momentarily/permanently switching them on). If you want to use another connector (e.g. 6.3mm TS) instead just connect the signals directly to the MAMI-QUAD tiles instead.
 
-| Top  | Bottom | 3D | Dimensions |
-| ---- | ------ | --- | ------ |
-| <img src="gerbers/MAMI-INPUT_Combined_Top.png" width="200px"> | <img src="gerbers/MAMI-INPUT_Combined_Bottom.png" width="200px"> | <img src="images/3d-input.png" width="200px"> | <img src="images/board_input.png" height="200px"> |
+| 3D | Dimensions |
+| --- | ------ |
+| <img src="images/3d-input.png" width="200px"> | <img src="images/board_input.png" height="200px"> |
 
 ## 2x2 Quad Tile [MAMI-QUAD]
 
-Mixes two inputs onto two outputs using 4 Potentiometers. The only other parts required are one 0805 resistor for each potentiometer.
+Mixes two inputs onto two outputs using 4 Potentiometers. The only other parts required are one 0805 resistor for each potentiometer. Note that the choice of value for this resistor will set the maximum gain of the mixer:
 
-| Top | Bottom | 3D | Dimensions |
-| ---- | ----- | --- | ------ |
-| <img src="gerbers/MAMI-QUAD_Combined_Top.png" width="200px"> | <img src="gerbers/MAMI-QUAD_Combined_Bottom.png" width="200px"> | <img src="images/3d-quad.png" width="200px"> | <img src="images/board_quad.png" height="200px"> |
+The formula to calculate the Gain is:
+
+$$Gain = 20 \cdot \log10{\frac{100 k\Omega}{R1}}$$
+
+| Resistor Value | Maximum Gain |
+| -------------- | ------------ |
+| 1k | 40dB |
+| 10k | 20dB |
+| 100k | 0dB |
+
+The 40 dB option should be enough to get consumer line level (e.g. headphone output from consumer devices) to eurorack levels.
+
+
+| 3D | Dimensions |
+| --- | ------ |
+| <img src="images/3d-quad.png" width="200px"> | <img src="images/board_quad.png" height="200px"> |
 
 
 ## Output Tile [MAMI-OUTPUT]
 
 Provides two 3.5mm Mono output jacks, with a Jumper (or switch) each row of tiles can be switched between unipolar and bipolar attenuation. Each  output is added to the next channel's output if no jack is plugged in (since rev 1.2). If you don't need normalization don't populate the parts `U3`, `R9`, `R10`, `R11`, `R12`, `R13`, `R14`, `C5` and `C6`
 
-| Top  | Bottom | 3D | Dimensions |
-| ---- | ------ | --- | ---- |
-| <img src="gerbers/MAMI-OUTPUT_Combined_Top.png" height="200px"> | <img src="gerbers/MAMI-OUTPUT_Combined_Bottom.png" height="200px"> | <img src="images/3d-output.png" height="200px"> | <img src="images/board_out.png" height="200px"> |
+| 3D | Dimensions |
+| --- | ---- |
+| <img src="images/3d-output.png" height="200px"> | <img src="images/board_out.png" height="200px"> |
 
 The summing section looks like this and allows a jumper (`J_ATT1` and `J_ATT2`) or a switch (2.54mm lead spacing) to be used to switch between unipolar and bipolar attenuation for each row separately.  
 <img src="images/schematic_summing.png" height="auto" width="600px">
@@ -64,9 +77,9 @@ The summing section looks like this and allows a jumper (`J_ATT1` and `J_ATT2`)
 
 A dual Envelope follower that can be hooked up to a `MAMI-OUTPUT`-Tile. Has two output jacks in the same 25mm spacing as the output module and two LEDs that correspond to the output levels.
 
-| Top  | Bottom | 3D | Dimensions |
-| ---- | ------ | --- | --- |
-| <img src="gerbers/MAMI-ENV_Combined_Top.png" height="200px"> | <img src="gerbers/MAMI-ENV_Combined_Bottom.png" height="200px"> | <img src="images/3d-env.png" height="200px"> | <img src="images/board_env.png" height="200px"> |
+| 3D | Dimensions |
+| --- | --- |
+| <img src="images/3d-env.png" height="200px"> | <img src="images/board_env.png" height="200px"> |
 
 # Erata 
 ### Output Module rev. 1.0 (has been fixed in 1.1)