The ADC2 is the successor of our renowned two channel ADC1-MK2 A/D Converter.
The ADC2 uses state of the art A/D chips in our proven “correlation technique” configuration, which lowers converter imperfections.
The analog input stages are kept balanced from the input connectors throughout to the converter chips. A high quality microphone preamplifier is built in as a standard feature.
Supported sampling frequencies are 44.1, 48, 88.2, 96, 176.4 and 192 kHz.
Output formats are AES/EBU in one or two wire technique, S/PDIF as well as Firewire for a direct connection to computers. (FireWire option not yet implemented).
Synchronization can be internal or external through AES/EBU or BNC (Wordclock).
The built in digital peak limiter allows for setting a generous headroom on the analog inputs and still get a full scale signal at the converter’s output.
A large bar graph shows the level to the A/D input, the output level and the gain reduction in the aforementioned Limiter.
The output wordlength can be reduced from 24 to 16 bits with the built in POW-R dithering. It is even possible to have one output running at 24 bits and another one at 16 bits. This feature comes handy when a safety copy to e.g. a DAT has to be made.
The analog input sensitivity can be set in 6dB steps via a relais controlled attenuator. An additional gain control is implemented in the DSP chip in the digital domain.
Both channel 1 and channel 2 are fully independent, except for the sampling rate and for the dither settings.
The AES/EBU sync input can be used as a digital audio input. This allows to limit and / or dither digital audio signals. The peak hold feature can be used to monitor a transfer and check for overloads which may have occured.

ADC2 Technical Data:
Analogue Line Inputs:
2 channels, symmetrical, not earth free, on two XLR female connectors, pin 2 hot.
Input Impedance > 5kOhm

Analogue Microphone Inputs:
2 channels, symmetrical, not earth free, on two XLR female connectors, pin 2 hot.
Input Impedance > 5kOhm
48V phantom power switchable

AES/EBU Input:
Input fs range: 44.1kHz
48.0kHz
88.2kHz
96.0kHz
176.4kHz
192.0kHz
All sampling frequencies must lie within +- 100ppm of the nominal sampling frequency.

Maximum Input Wordlength: 24 Bits
Connector: XLR female
Impedance: 110 Ohm

AES/EBU Output:
Output fs range: 44.1kHz
48.0kHz
88.2kHz
96.0kHz
176.4kHz
192.0kHz

Maximum Output Wordlength: 24 Bits
Channel Status Data: Professional format
Connector: two times XLR male
Impedance: 110 Ohm
Format: single wire or double wire for fs higher than 48kHz
(switch selectable)

S/PDIF Output:
Output fs range: 44.1kHz
48.0kHz
88.2kHz
96.0kHz
176.4kHz
192.0kHz

Maximum Output Wordlength: 24 Bits
Channel Status Data: Professional format
Connector: RCA female
Impedance: 75 Ohm

WORDSYNC I/O:
Input Connector: BNC female
Input Impedance: 75 Ohm
Input Level: TTL

Output Connector: BNC female
Output Impedance: 4.7 Ohm
Output Level: TTL

Firewire:
Not implemented in software version 1.0

Power:
Mains Voltage: 110 / 220 Volts with voltage selector
Fuse rating: 0.63A slow blow
Power Consumption: 60VA max.

Low cut frequency response:
1st order highpass, 3dB point at 40Hz

Frequency Response:
@ fs = 44.1kHz: 20Hz ... > 20kHz +- 0.3dB
@ fs = 48.0kHz: 20Hz ... > 20kHz +- 0.3dB
@ fs = 88.2kHz: 20Hz ... > 30kHz +- 0.3dB
@ fs = 96.0kHz: 20Hz ... > 30kHz +- 0.3dB
@ fs = 176.4kHz: 20Hz ... > 40kHz +- 0.3dB
@ fs = 192.0kHz: 20Hz ... > 40kHz +- 0.3dB

THD+N @ 1kHz:
less than -103 dBFS @ -3 dBFs output level, unweighted

SNR @ -40dBFS input:
> 110dB unweighted

Linearity:
t.b.d.

Crosstalk:
< -120dB, 0..20kHz

CMRR:
> 90dB @ 1kHz
> 80dB @ 20kHz
> 60dB @ 20Hz

Interchannel phase tracking:
Better than +- 0.3°, 20Hz to 20kHz

All measurements taken at the least sensitive setting of the input attenuators, i.e. +24dBu sensitivity for line and +6dBu sensitivity for mic inputs. (= sensitivity for 0dBFS output level).

Parameter Tables
Analogue Gain Line Input [dB]:
-24.0, -18.0, -12.0, -6.0, 0.0, +6.0, +12.0, +18.0, +24.0, +30.0, +36.0
(example: with a gain setting of -24.0, a +24dBu input signal generates a 0dBFS output)
Analogue Gain Mic Input [dB]:
+6.0, +12.0, +18.0, +24.0, +30.0, +36.0, +42.0, +48.0, +54.0, +60.0

Digital Output Gain [dB]:
-100.0 , -92.0 , -89.0 , -86.0 , -83.0 , -80.0 , -77.0 , -74.0 , -71.0 , -68.0 , -65.0 , -62.0 , -59.0 , -56.0 , -53.0 , -50.0 , -48.0 , -46.0 , -44.0 , -42.0 , -40.0 , -39.0 , -38.0 , -37.0 , -36.0 , -35.0 , -34.0 , -33.0 , -32.0 , -30.0 , -29.5 , -29.0 , -28.5 , -28.0 , -27.5 , -27.0 , -26.5 , -26.0 , -25.5 , -25.0 , -24.5 , -24.0 , -23.5 , -23.0 , -22.5 , -22.0 , -21.5 , -21.0 , -20.5 , -20.0 , -19.5 , -19.0 , -18.5 , -18.0 , -17.5 , -17.0 , -16.5 , -16.0 , -15.5 , -15.0 , -14.5 , -14.0 , -13.5 , -13.0 , -12.5 , -12.0 , -11.5 , -11.0 , -10.5 , -10.0 , -9.5 , -9.0 , -8.5 , -8.0 , -7.5 , -7.0 , -6.5, -6.0 , -5.8 , -5.6 , -5.4 , -5.2 , -5.0 , -4.8 , -4.6 , -4.4 , -4.2 , -4.0 , -3.8 , -3.6 , -3.4 , -3.2 , -3.0 , -2.8 , -2.6 , -2.4 , -2.2 , -2.0 , -1.8 , -1.6 , -1.4 , -1.2 , -1.0 , -0.8 , -0.6 , -0.4 , -0.2 , 0.0 , 0.2 , 0.4 , 0.6 , 0.8 , 1.0 , 1.2 , 1.4, 1.6 , 1.8 , 2.0 , 2.2 , 2.4 , 2.6 , 2.8 , 3.0 , 3.2 , 3.4 , 3.6 , 3.8 , 4.0 , 4.2 , 4.4 , 4.6 , 4.8 , 5.0 , 5.2 , 5.4, 5.6, 5.8 , 6.0 , 6.2 , 6.4 , 6.6 , 6.8 , 7.0 , 7.2 , 7.4 , 7.6 , 7.8 , 8.0 , 8.2 , 8.4 , 8.6 , 8.8 , 9.0 , 9.2 , 9.4 , 9.6 , 9.8 , 10.0 , 10.2 , 10.4 , 10.6 , 10.8 , 11.0 , 11.2 , 11.4 , 11.6 , 11.8 , 12.0 , 12.2 , 12.4 , 12.6 , 12.8 , 13.0 , 13.2 , 13.4 , 13.6 , 13.8 , 14.0 , 14.2 , 14.4 , 14.6 , 14.8 , 15.0 , 15.2 , 15.4 , 15.6 , 15.8 , 16.0 , 16.2 , 16.4 , 16.6 , 16.8 , 17.0 , 17.2 , 17.4 , 17.6 , 17.8 , 18.0

Compressor Threshold [dBFS]:
-25.0 , -24.8 , -24.6 , -24.4 , -24.2 , -24.0 , -23.8 , -23.6 , -23.4 , -23.2 , -23.0 , -22.8 , -22.6 , -22.4 , -22.2 , -22.0 , -21.8 , -21.6 , -21.4 , -21.2 , -21.0 , -20.8 , -20.6 , -20.4 , -20.2 , -20.0 , -19.8 , -19.6 , -19.4 , -19.2 , -19.0 , -18.8 , -18.6 , -18.4 , -18.2 , -18.0 , -17.8 , -17.6 , -17.4 , -17.2 , -17.0 , -16.8 , -16.6 , -16.4 , -16.2 , -16.0 , -15.8 , -15.6 , -15.4 , -15.2 , -15.0 , -14.8 , -14.6 , -14.4 , -14.2 , -14.0 , -13.8 , -13.6 , -13.4 , -13.2 , -13.0 , -12.8 , -12.6 , -12.4 , -12.2 , -12.0 , -11.8 , -11.6 , -11.4 , -11.2 , -11.0 , -10.8 , -10.6 , -10.4 , -10.2 , -10.0 , -9.8 , -9.6 , -9.4 , -9.2 , -9.0 , -8.8 , -8.6 , -8.4 , -8.2 , -8.0 , -7.8 , -7.6 , -7.4 , -7.2 , -7.0 , -6.8 , -6.6 , -6.4 , -6.2 , -6.0 , -5.8 , -5.6 , -5.4 , -5.2 , -5.0 , -4.8 , -4.6 , -4.4 , -4.2 , -4.0 , -3.8 , -3.6 , -3.4 , -3.2 , -3.0, -2.8 , -2.6 , -2.4 , -2.2 , -2.0 , -1.8 , -1.6 , -1.4 , -1.2 , -1.0 , -0.8 , -0.6 , -0.4 , -0.2 , 0.0

Sampling Rate [kHz]:
44.1, 48.0, 88.2, 96.0, 176.4, 192.0
POW-R Noise Spectrum
Fig. 1 shows the noise spectrum of the three POW-R algorithms at 44.1 and 88.2 kHz.