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      02-19-2009, 10:45 PM   #74
Lieutenant General
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Drives: 2015 320i
Join Date: Apr 2005
Location: Ft Lauderdale, Florida

iTrader: (18)

Three devices...

... into (bit) one:

In a nutshell, the bit one solves a couple of issues (hiss introduced by the Cleansweep to keep the OEM volume functional, and some random whine at start up) of my past setup while further improving the sound quality due to many more adjustment capabilities.

Definitely this DIRAC system does something with the voices, because this bit one also fix that completely and then some. Clarity and loudness are improved, even more after tuning. A very nice feature is Dynamic Equalization, which allows the user to compensate with a full 31-band EQ the volume at low and high levels (set also by the user). This is like a very detailed "loudness" setting: at low volume you can set an EQ curve on top of the main EQ curve, and the same at high volume to compensate for specific frequencies (mostly bass) listening levels lost due to volume level.

However, in the Premium Audio in particular the "De-Equalization" calibration procedure of the bit one requires that the high level outputs from the OEM amp be somewhat reduced or the bit one will saturate causing the low frequencies to not be summed to the high frequencies. There was a change in specs from the initial documentation of the bit one that stated that the high level inputs max rating was around 32V RMS, or 46V peak, and now the latest documentation states that the max high level input is 20V peak.

The OEM amp in the Premium Audio puts out at least 100W RMS at 7 ohms at the OEM woofers, which converts to at least 26V peak, which will saturate the bit one high level inputs. So when calibrating this unit with a Premium Audio system this has to be taken into consideration or it will not calibrate correctly. I do not think that either the base HiFi or the Logic 7 will have this issue, as these OEM amps are less than half in power output compared to the Premium Audio, and in the case of the HiFi there's no need to use the high level inputs or its OEM amp anyway as the OEM HU/iDrive outputs analog low level differential so the low level inputs of the bit one can be used in base systems.

The good news for Logic7 and Premium Audio owners: mObridge is coming in a couple of months with the first MOST digital converter box, in either Toslink output (direct compatibility with the bit one as Audison is developing this converter with mObridge) or preamp outputs (direct to aftermarket amps). So no more Cleansweep, no more any channels summing, no more any "De-EQ" to correct for OEM processing. Just direct digital interface from the OEM HU/iDrive, completely bypassing the digital OEM amp.