As far as we know, the Ark8 is the only console which offers support for both 500 and 51x modules.

The middle section of the input channels and/or the master section can have two rows of 8 slots for 500/51x modules (for a total of 16 slots per block of 8 channels and/or per master section).

Note that none of these slots are “tied” to the channels.
Actually the slots are totally independent from the rest of the console.
They have their own I/O connectors on the back panel, and even have their own power supply.

Consider it one or two 8-slot racks which are installed in the
Ark8.

This allows full flexibility, since you can use any 500/51x module (or chain of modules) on any channel.


What is the difference between 500 slots and 51x slots?

500 slots use
15-pin EDAC connectors. 51x slots use 18-pin EDAC connectors.

The first 15 pins of the 51x 18-pin connector are used in the exact same way as the original 500 series rack.
51x slots are fully compatible with standard 500 series compliant modules.
This means you can either use 500 modules or 51x modules in a 51x slot.
51x modules can only be used in 51x slots.

500 and 51x modules have the same dimensions, only the connector is different.


What are the additional connection points on the 51x slots used for?

These are used for +/- 24 Volt power rails.
Since the Ark8 runs on these +/- 24 Volts power rails, this makes perfect sense.

We are the only console manufacturer offering support for 51x modules.
We offer this support, so the large DIY community out there can make use of this to design and build modules requiring +/- 24V, like NEVE, Neumann or Telefunken style circuits.
We also hope to make it easier for other manufacturers to start using this improved specification and look forward to a range of high-quality 51x modules.


Pins Old API 500 Specifications Current Use In Market Ark 500 pin layout Ark 51x pin layout Pins
500 series  EDAC 306-015-520-102 connector 51x series  EDAC 306-018-520-102 connector
1 Chassis Ground Chassis Ground Chassis Ground Chassis Ground 1
2 Output + (+4 dB level) Output + Output + Output + 2
3 Output + (-2 dB level) not used not used not used 3
4 Ouput - Output - Output - Output - 4
5 Ground (analogue) Ground (analogue) Ground (analogue) Ground (analogue) 5
6 Stereo Link Stereo Link Stereo Link Stereo Link 6
7 Input - (-2 dB level) not used not used not used 7
8 Input - (+4 dB level) Input - Input - Input - 8
9 Input + (-2 dB level) not used not used not used 9
10 Input + (+4 dB level) Input + Input + Input + 10
11 Gain Trim Resistor not used not used not used 11
12 +16V DC +16V DC +16V DC +16V DC 12
13 Ground (power) Ground (power) Ground (power) Ground (power) 13
14 -16V DC -16V DC -16V DC -16V DC 14
15 +48V DC +48V DC +48V DC +48V DC 15
  - - - Not used 16
  - - - +24V DC 17
  - - - -24V DC 18
Pins Old API 500 Specifications Current Use In Market Ark 500 pin layout Ark 51x pin layout Pins
Side note on power

All modules of the
Ark8 have power regulators on board, to make sure they run at the cleanest power.
(see our
“power” page)

500 or 51x modules don’t have these power regulators on board.

To make sure that the 500 and 51x modules get the cleanest power, we installed power regulators on the 500/51x motherboard.

Your modules will thank us for this.