Aphex Systems 228

Aphex Systems 228

Audio Quality

This is not just a buzzword at Aphex. Our products are known around the world for their ultra high sound quality. It's our benchmark. Given that the Model 228 is a relatively simple product, nothing more than a level interface, we placed a high priority on endowing it with the best sound quality possible. That's why we designed it with high voltage impedance balanced outputs and ground loop isolating unbalanced inputs. The audio circuitry was carefully crafted throughout to maximize sonic performance. There are no cookbook circuits in the 228.

Aphex Leads The Way

There are plenty of stereo level interfaces out there from various manufacturers. Of these, the Aphex 124A enjoys a reputation as the one of the world’s finest. The 124 blazed a trail with it’s high definition servo balanced input and output circuits and remains as the premier bidirectional stereo level interface. However, the need for something else is becoming acute.

Today’s multichannel sound of 5, 6, 7 or more channels makes using two channel interfaces cumbersome and expensive. Furthermore, the greatest need by far is to translate consumer level outputs to professional level inputs. Bidirectionality is seldom needed. That’s why Aphex created the Model 228 Unidirectional Level Interface. It is perfectly suited to the vast majority of multichannel uses in the studio and the theater.

Unmatched Reliability

Aphex engineering and manufacturing produces products that last and last without need for repairs or calibration. Some of our products have literally been in 24-hour use in the same rack for a decade or longer! When you specify a Model 228, you know it will do its job flawlessly and give you peace of mind. 

Useful Extras

The 228 combines outstanding audio performance with utility features that will make your installation and operation much easier. The front panel extended range VU meter lets you calibrate and monitor each channel individually. Eight 2-color signal presence/clip indicators let you know instantly if sound is present on each channel and if overload occurs.

Front panel gain trims for all eight channels allow you to balance the match gain. Fully clockwise, gain is calibrated to the reference 11.78dB. Counterclockwise, the trimmer attenuates by 12dB, giving you unity gain. For theater installations, a provision is made to dim all the lights on the front panel.

A test CD with commonly used reference levels is included for easily matching up your specific equipment.

Level Translation: A Very Brief Tutorial

Mixing of consumer and professional grade audio equipment is occurring more and more. For example, consumer DVD players cost far less than pro versions, but don’t readily connect to the input of a studio console or monitor system. Another example: the high-end power amplifiers being used in home theaters have balanced line level inputs and can’t be driven directly from the consumer decoders and preamps. In such cases, a multichannel consumer-to-pro level interface is needed that can receive from a consumer level RCA jack at -10dBV (316mV RMS) and send to a pro level XLR jack at +4dBu (1.228V RMS). That requires a voltage gain of 3.886, which can also be stated as 11.79dB.

Typical Uses

Broadcast, Recording, Film, Home Theater, Installed and Mobile Sound, DAW Input, Mastering.

Features

• 8 Discrete -10dBV RCA inputs

• 8 Discrete +4dBu XLR Outputs

• 8 Signal Presence/Clip Lights

• Extended Range VU Meter

• 8 Gain Trims

• Gold Plated Connectors

• Calibrated 11.78dB Gain (Exact -10dBV to +4dBu translation)

• 12dB Attenuation Range (Great for unity gain applications)

• Low Noise

• High Definition Audio

• Impedance Balanced Outputs

• High Reliability

• Front Panel Dimming

SPECIFICATIONS - Aphex Model 228 8 Channel Unidirectional Level Interface

AUDIO

• Inputs 8 unbalanced RCA

• Outputs 8 Balanced XLR 3-pin Male

• Gain Translation 11.78 dB Adjustable ±6 dB

• Frequency Response -3dB @ .16 Hz and 80 kHz

• THD @ max output Less than .001% at M.O.L.

• IMD @ max output Less than .001% at M.O.L.

• Output Noise Better than -90dBu, input shorted

• SNR 94 dB

• Dynamic Range 114 dB

• Max Output Level (MOL) +24dBu

• Max Input Level 3.55V RMS

OTHER SPECIFICATIONS

• Power Requirements 100 / 120 / 220 / 240 VAC 50-60 Hz   20 Watts max  

• Dimensions 19"W x 1.75"H x 9" D (482.6mm x 44.5mm x 228.6mm)

• Power Supply Internal, Fused

• Net Weight 5 lbs (2.27 kg)