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Programs’ Effect on Routing Decisions
As you’ll recall from the Quickstart section, to the right of every program name in the PROGRAM area there are two digits called the "I/O Identifier." On the screen shown to the right:
"Q*10 Grafic Eq" has an "I/O Identifier" of "44" "O*5 Grafic Eq" has an "I/O Identifier" of "88" "Gaspodes Dly_2" has an "I/O Identifier" of "32" "Gaspodes Dly_M" has an "I/O Identifier" of "22"
To understand why the "I/O Identifier" is necessary, we must first understand that, although each DSP has eight inputs and eight outputs, it is not necessarily the case that all of those inputs and outputs will be used by a given program. As has been stated elsewhere in this manual, each program is a unique algorithm. The particulars of a given algorithm dictate how many inputs and outputs will be used, just as they dictate what sorts of parameters are used. For example, a program that acted as a synthesizer would not need any inputs. A program that turned a mono signal into a pseudo-quad signal would only need one input. A program that modulated one stereo signal with another stereo signal would only need two outputs.
So, the "I/O Identifier" tells us at a glance how many inputs and outputs a program uses. The first digit refers to the number of active (live) inputs to the program, and the second digit refers to the number of active (live) outputs to the program. The way these digits correspond to actual inputs and outputs is as you would expect:
0 x |
the program has no inputs. It could be an oscillator or sound effects |
generator. |
|
1 x |
input 1 is live; inputs 2, 3, ..., 8 are dead. |
2 x |
inputs 1 and 2 are live; inputs 3, 4, ..., 8 are dead. |
and so on! |
|
x 0 |
the program has no outputs. Perhaps it's a spectrum analyzer. |
x 1 |
output 1 is live; outputs 2, 3, ..., 8 dead. |
x 2 |
outputs 1 and 2 are live; outputs 3, 4, ..., 8 are dead. |
and so on. |
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If the I/O Identifier is not visible, this means either that the program has no inputs or outputs (unlikely, except for a small number of information-only presets) or that the program file does not contain I/O Identifier information - this will usually only apply to presets obtained from a DSP4000 or other earlier system.
Be mindful of the "I/O Identifiers" when you select your programs and routing configurations. You won’t want to make connections to dead inputs or outputs unless you plan not to use those dead inputs or outputs! You may find yourself frequently ignoring dead inputs or outputs, especially if you load quad or octal routing configurations but only process stereo signals. As long as you don’t fool yourself into thinking the dead inputs or outputs are passing audio, everything is OK! Let’s look at a few examples of routing configurations that rely on connections to dead inputs and outputs and, because of that reliance, fail to do any business.
For example, the setup shown to the right is bad news. The inputs to DSP A will never be heard because the program "VocalVerb 2" doesn’t use DSP inputs 3 and 4! Remember, the first digit in its "I/O Identifier," "2," means that only inputs 1 and 2 are live. Inputs 3 through 8 are dead (they’re shown as dotted circles in the diagram). You won’t hurt the H8000FW by hooking things up this way, but you won’t pass audio!
To the right, we have another bad scene. The program "Big Voice" has an "I/O Identifier" of "22." That means that only DSP outputs 1 and 2 are live. Outputs 3 through 8 are dead, but in the block diagram to the right, it is these dead outputs that are being used. Again, you won’t hurt the H8000FW by hooking things up this way, but you won’t pass audio!
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1 |
1 |
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1 |
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block |
2 |
2 |
running |
2 |
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4 |
4 |
4 |
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3 |
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3 |
DSP A |
3 |
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Input |
5 |
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5 |
“Vocal |
5 |
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6 |
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6 |
I/O = 28 |
6 |
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Verb 2” |
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7 |
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7 |
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7 |
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8 |
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8 |
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8 |
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1 |
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1 |
1 |
ANA1 |
2 |
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2 |
2 |
ANA2 |
3 |
DSP A |
3 |
3 |
ANA3 |
4 |
running |
4 |
4 |
ANA4 |
5 |
“Big |
5 |
5 |
DIG1 |
Voice” |
||||
6 |
I/O = 22 |
6 |
6 |
DIG2 |
7 |
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7 |
7 |
DIG3 |
8 |
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8 |
8 |
DIG4 |
Of course, making a connection to a dead input or output is not necessarily a bad thing. You can make "dead connections" as long as you don’t fool yourself into thinking that they’re actually passing signals. For example, you might want to filter a simple stereo signal. You’ll use digital inputs 1 and 2 and digital outputs 1 and 2. You don’t care what’s happening on the rest of the
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You are actually only using inputs 1/2 and outputs 1/2
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1 |
1 |
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1 |
1 |
ANA1 |
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block |
2 |
2 |
running |
2 |
2 |
ANA2 |
4 |
4 |
4 |
4 |
ANA4 |
||
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3 |
3 |
DSP A |
3 |
3 |
ANA3 |
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Input |
5 |
5 |
“Stereo |
5 |
5 |
DIG1 |
6 |
6 |
I/O = 22 |
6 |
6 |
DIG2 |
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Filter” |
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7 |
7 |
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7 |
7 |
DIG3 |
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8 |
8 |
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8 |
8 |
DIG4 |
digital inputs and outputs. You load the program "Stereo Filter" with an "I/O Identifier" of "22."
For convenience, you load the routing configuration "AES 8 track A only," which makes connections as shown above. Connections are in fact made to the dead inputs 3 through 8 and the dead outputs 3 through 8, but it doesn’t matter in this case. You aren’t attempting to pass signals on these "dead connections" ! You’re only using the live inputs 1 and 2 and the live outputs 1 and 2. Again, making a "dead connection" isn’t a bad thing as long as you don’t fool yourself into thinking that it’s actually passing a signal!
The moral? Not all the inputs and outputs on a given DSP are necessarily live. Exactly how many are live depends on the program that is being run. To prevent signals from becoming "lost," keep the "I/O Identifier" and its impact on your routing configuration in mind!
Before we leave this section, we should mention that, although we just asked you to always keep the "I/O Identifier" in mind, you will seldom need to alter a chosen routing configuration to suit a program in practice. You’ll find that things tend to work out better than the "bad news" examples above might lead you to believe!
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CONTROLLING LEVELS
The Level Meters
Now that you’re comfortable routing signals in the H8000FW, we can explore the Level Meters. Once you understand the Level Meters, you can adjust levels along the signal path. There are
eight individual meters to the left of the display. By altering the Source parameter on the meter menu page in the LEVELS area, you can change the point in the signal path that the meters measure. Your choices are:
inputs measure the level at the input block (as defined on the inputs menu page in the SETUP area). In post-fade mode, the meters reflect level cuts made on the inputs menu page in the LEVELS area. In pre-fade mode, the meters do not reflect these cuts.
machine inmeasures the level at the inputs to the currently displayed DSP. To measure the level at the inputs to the DSP not currently displayed, press the PROCESSOR A/B key. In post-fade mode, the meters reflect level cuts made on the dsp A or dsp B menu page in the LEVELS area. In pre-fade mode, the meters do not reflect these cuts.
machine out measures the level at the outputs to the currently displayed DSP. To measure the level at the outputs to the DSP not currently displayed, press the PROCESSOR A/B key. In post-fade mode, the meters reflect level cuts made on the dsp A or dsp B menu page in the LEVELS area. In pre-fade mode, the meters do not reflect these cuts.
outputs measure the level at the AES/EBU outputs (H8000) or at the analog and AES/EBU outputs (H8000A, H8000FW). The S/P DIF output level is equivalent to AES/EBU 1/2 and in the H8000 the analog output level is 7/8. The ADAT output levels depend on which outputs were assigned to which ADAT outputs. The levels reflect cuts made on the outputs menu page in the LEVELS area (there is no post-fade/pre-fade distinction when monitoring the outputs).
The order parameter determines the order of signals. Usually you will leave this at 1-4, 5-8. Your other option is to "flip" the first and last four inputs/outputs on the meters: 5-8, 1-4.
This is mostly useful for viewing an 8-channel signal on an Eve/Net™ remote with 4- channel metering.
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The parameter decay time determines how long the meters take to go from full "deflection" to zero measuring an impulse. The parameter peak hold determines how long the meters hold their highest reading.
The Level Meters are useful for two reasons. First, you can use them to verify that your internal gain structure is in good shape. You generally want to keep levels near, but not touching, the red clip LED. To achieve this, it’s always better to boost or cut an output. Only if a signal level cannot be optimized by an output boost/cut should you resort to altering an input level! Second, the Level Meters can be used to troubleshoot routing problems. If, for example, you hear nothing at the output of the H8000FW, and you think your signal path goes from the analog inputs to DSP B to DSP A to the digital outputs, you can use the Level Meters to check that signal exists at every point along the way. The point in the path at which the signal "dies" will clue you in to what routing or level parameter has been set incorrectly.
Don’t forget about the "I/O Identifier" when troubleshooting. See Programs’ Effect on Routing Decisions on page 69.
Controlling the Level of the Analog and Digital Inputs
Signals come into the H8000FW from the outside world via the input block. Adjust the boost/cut of each of these eight inputs on the inputs menu page in the LEVELS area. Such
boost/cuts will often be made in "gangs." However, you can boost/cut any of the eight inputs independently of the others by pressing the key.
are not saved or loaded with routing configurations in the Routing Storage area.
See Ganged Parameters on page 20 for more about "gangs."
The "top" menu page (shown above for the H8000FW) makes cuts of 0dB to 100dB in the digital domain. Any cuts made to the analog input on the "top" page are after digital
conversion. The "bottom" menu page (shown to the right for the H8000) makes analog boosts/cuts of +30dB/-90dB in the analog domain before conversion. Except in rare instances, it is usually preferable to optimize the analog input signal level on the "bottom" menu page, that is, in the analog domain.
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To monitor the input levels, go to the meter menu page in the LEVELS area. Change Source to inputs. Select post-fade if you would like to monitor levels after the aforementioned cuts.
Select pre-fade if you would like to monitor levels before the aforementioned cuts.
It is possible to overdrive an input to the H8000FW, decrease that overdriven level at the inputs page, and show no clipping on the Level Meters when viewing post-fade! To avoid such a situation, it is advisable that you boost/cut the signals coming into the H8000FW at their source. Doing so also results in a better gain structure! The moral? Use the boost/cut on the inputs page only as a last resort.
Note: All of the parameters discussed in this section can be "remote controlled" via MIDI or the foot pedal
jacks. To learn how, read:
Setting Up the External Controllers on page 92.
External Modulation and Trigger Menu Pages on page 96.
Remote Controlling Parameters on page 111.
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Input Levels, Wet/Dry Ratios, and Output Levels for Each DSP
You can control the input level for each input of each DSP, the wet to dry ratio of each "channel" of each DSP, and the output level for each output of each DSP. All of these settings are saved and loaded with a routing configuration in the Routing Storage area.
See Signal Flow Example on page 64.
The input level for each input of DSP A is controlled on one of the many "stacked" dsp A menu pages in the LEVELS area. You can cut the input signal from 0 to -100 dB. By pressing the
DOWN CURSOR key to "un-gang" the parameters, cuts can be made on single inputs independently of the others.
The input level for each input of DSP B is controlled on the dsp B menu page located "below" the dsp A menu page in the LEVELS area. Again, you can cut the input signal from 0
to -100 dB. By pressing the DOWN CURSOR key to "un-gang" the parameters, cuts can be made on single inputs independently of the others.
To change the wet to dry ratio for each "channel" of DSP A, find the appropriate menu page in the dsp A menu page "stack" in the LEVELS area. At 100%, the signal coming out
of an output is completely processed. At 0%, the signal coming out of an output is identical to the signal applied to the corresponding input. For example, if you set A OUT2 Wet/Dry to 0%, the signal at DSP A output 2 will be the same as the signal at DSP A input 2. A setting between 0% and 100% mixes the processed and input signals as you would expect. Pressing the DOWN CURSOR key "un-gang" the parameters and allows you to control the Wet/Dry ratio of any "channel" independently of the others.
Use of the word "dry" may cause some confusion. Normally, if you set an effects box to "dry," the output of the box is the same as its input. However, the "Wet/Dry" control on the H8000FW is not at the box level, it’s at the DSP level. To understand the ramifications of this, pretend we’re sending a signal from the "inputs block" to DSP B. The program loaded on DSP B is a dense reverb and the OUTx Wet/Dry parameters for all eight outputs of DSP B are set to 100% (the output is totally processed). Now, let’s say you connect all eight outputs of DSP B to the inputs of DSP A. That would mean that the signals at the inputs to DSP A are reverberant. Now, let’s say you set the OUTx Wet/Dry parameters for all eight outputs of DSP A to 0% (not processed at all). DSP
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