The channel EQ in the d8b is known to generate a small amount of very low frequency noise when engaged. The different EQ modes (British High Pass, 20/20, etc.) produce different amounts of noise at different frequencies. The noise is cumulative so the more channels with the EQ engaged, the louder the noise, up to a certain point.
While it may accumulate to significant levels, it remains inaudible due to the fact that this noise resides largely in the range below 10 HZ, increasing as it approaches DC, below the capacity of the best sub woofers or the human ear.
A decrease in noise level by over 10 dB has been observed when a TC Finalizer high pass filter was enabled at 5 Hz, between the d8b LR out and a DAW, via AES.
While inaudible in itself, sub-sonic noise can place considerable stress on power amplifiers and speakers, overheating components and compromising audible frequencies.
For this reason, it is suggested that you apply a steep high pass filter (set between 5 and 40 Hz, depending on the music) to your mixes, either while recording the mix (as in the configuration above), or in mastering.
The Channel Filter “feature” on the d8b Channel List page does not work as intended, and should be disabled on every channel.
If not, you will hear a noise similar to static, and may experience very soft signals being muted.
To disable the Channel Filters go to the Channel List under the Channel menu (the Control/B shortcut does not always work). On the far right side, set every channel to Off. Best to save a default start up mix after this, so you will not need to revisit the issue in the future.
The Channel Filter idea was to provide a noise gate before the A/D converters, that would sense the noise level of connected equipment on boot up, and prevent noise from using the least significant of the 24 bits available.
In spite of the good intentions, the idea never worked as intended, and when on, the Channel Filter gates are subject to chattering and soft bursts of noise.
At the top of the VDU, to the right of the Menu section and to the left of the "Session" name indicator, is another little indicator that shows the "Memory" available for further data entry.
Sometimes, after long periods of heavy use and Automation procedures, the displayed number can begin flashing between 0 and a higher number. It doesn't matter what that higher number is.
If this happens, it is a sure sign that something is amiss and you should save your work immediately, preferably with a suffix ammendment and re-boot.
The meters on the d8b indicate O/L (red) early. This was supposedly to help users by offering a margin for error.
The Channel O/Ls come on at -0.95 dBfs.
The L/R Master O/Ls come on at -0.58 dBfs.
0dBfs = Full scale digital = you don’t have no more headroom for those cowbell transients.
Note that all digital audio meters, hardware and software, use their own meter ballistics which are not standardized. Some show red lights as low as -4 or -5 dBfs. Others, at a certain number of samples reaching or approaching full scale. Some devices have user adjustable settings for this parameter.
Also note that there is really no such thing as an "Overload" (in the analog sense) at a digital input, as the input cannot receive a signal greater than full scale (although there is certainly a risk of overloading circuits before or after the input). Of course, the analog stage of an analog to digital converter can be overloaded.
The "OL" indicators or red lights on digital inputs should be thought of as warnings, rather than as a precise indicator of signal strength, loudness or distortion.
Do not attempt to change the Video monitor Refresh Rate under “Windows menu>Setup>Refresh Rate” if using O.S. V5 or V5.1.
This may incur a fatal crash that can only be rectified by a full format of your HD and re-installation of the OS.
Issue #40: Changing the refresh rate has no effect.
Workaround: None. Do not change the refresh rate.
Some users have reported problems, others have not. Whatever, to change it makes no difference to the monitor’s appearance so it’s best left alone.
If you have not kept back-ups of all mixes etc. and this problem occurs, you will lose all of your data.
It would be advantageous to grab a copy of the known issues regarding V5.1 OS by downloading this PDF file so that you are fully up to speed with any anomolies.
Press and hold the Channel Select button for a few seconds and the Fat Channel fluoro display will come alive with the following parameters for the selected channel that can be controlled from the desk surface:
- Group Assign
- Playback Mode (Run/Punch Run/Disabled)
- Channel Delay
- Plug Pre
- Plug Post
- Pre Patch
- Key Insert
- Phase Flip