Linear Acoustic has released two upmixing processors – the Upmax II Reference Upmixer and Upmax 5.1 Channel Upmixer.
Creating consistent, high-quality broadcast audio increasingly requires more than stereo programmes reproduced from the left and right channels of a 5.1-channel system. Linear Acoustic’s Upmax and Upmax II creating a 5.1-channel signal from a stereo source, with the Upmax II allowing user control over the soundfield, while the 1U-high Upmax provides cost-effective, space-efficient upmixing. Both produce fully downmix-compatible left, right, centre, stereo surround, and LFE channels from the two-channel main input.
The new Upmax II algorithm produces a very stable 5.1-channel version of two-channel inputs. Audio elements are extracted using frequency domain filtering and time domain amplitude techniques. The bass enhancement signal for the LFE channel is derived from the left, centre and right channels, allowing quick creation of subwoofer channel elements without compromising full-range consumer playback systems. The surround field can be infinitely adjusted via the Centre Channel Width control and the Surround Channel Depth controls. This allows programming ranging from simple stereo to LtRt to be appropriately reproduced from a 5.1-channel playback system.
Upmax II accepts three AES pairs of audio – it will upmix the first pair, and passes all three pairs via a crossfade when upmixing is disabled. This allows the unit to remain in a 5.1-channel path. Upmixing and bypass can be controlled by GPI contact closure and applied metadata. Upmax II also includes a utility encoder that accepts 5.1 channels and produces a two-channel LoRo, LtRt, or LtRt2 output; this encoder can be independent or it can be fed by the same channels applied to the upmixer.
Optional HD/SD-SDI I/O is available, allowing access to all 16 embedded audio channels. Audio can be processed or passed without modification from any embedded input pair to any embedded output pair, allowing utility channel pair shuffling.
Based on the original Upmax 2251, the Upmax offers a stable and trusted algorithm in a cost- and space-efficient package, perfect for remote OB trucks. The upmixed output is completely downmix compatible; the downmixed result is nearly indistinguishable from the original two-channel input. Upmixing can be controlled via the front panel, GPI inputs, or metadata from serial or VANC (SDI) sources applied to the unit. A bright LED display, rotary encoder, and four control keys provide straightforward menu navigation and function adjustment. Dual redundant auto-ranging power supplies are standard. Bypass relays are provided for trouble-free operation in transmission critical environments.
Upmax also includes a utility encoder that accepts 5.1 channels and produces a two-channel LoRo or LtRt output. This encoder can be independent or it can be fed by the same channels applied to the upmixer.
Optional HD/SD-SDI I/O is available, allowing access to all 16 embedded audio channels. Audio can be processed or passed without modification from any embedded input pair to any embedded output pair, allowing utility channel pair shuffling.
More: www.linearacoustic.com
