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 Post subject: SPEC 4.2.1 with ZAG 1.7
PostPosted: Mon Mar 29, 2010 10:56 pm 
SBU Wiki Team
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Joined: Sun Aug 30, 2009 7:01 am
Posts: 656
Discussion about this Guide, SPEC 4.2.1, and ZAG 1.7 can be found here:


Note: Not the current version, attachment deleted

SPEC 4.2.1 Addendum

Note: If you downloaded this version prior to 4/2/2010 at 2PM PDT then you should replace ZAG 1.7.1.dll
in your plugins folder with the one in the above or with the ZAG 1.7.dll posted in the discussion thread
(They are functionally the same)

Edit: 4/19/10 Upgraded Installer with error notification, added more details to Readme file. No changes to SPEC.

Edit 4/23/10 fixed (again!) the version of ZAG. Sorry folks! Also added Zmon to the layouts with ZAG. Connect your Audio Device to the bottom of Zmon.


This guide covers the changes from SPEC 4.0


Plogue 0.9702 or newer (32 bit standalone, even if you have a 64 bit OS)

Review the Plogue Guide, for Plogue preferences:


Use the included installer. Just double click on XP_intaller.bat , for Windows XP, or Vista_7_Installer.vbs for Vista or Windows 7 (32 or 64 bit).

Start Plogue and open the SPEC421_Release.bidule layout:


Let’s take a look at what is new here:


The pre-gain function remains unchanged from SPEC 4.0. Below it, though, you will find the new “Output Clip” feature. During your initial
run-through, the button to the right will turn red when there is an incident of output clipping on any channel. In order to prevent any
distortion in the mix, it is important that you adjust your pre-gain to a level where the output clip does not light up. A few flashes of the clip
indicator in a song is not a reason to start a whole conversion over again (as we are doing 32 bit float processing) but you should check
a “loud” portion of your stereo before moving on to other SPEC settings. Keep an eye on the clip indicator as you make other setting
changes, as the different methods, and the output gains, will affect the final output level.

The Slice, CC, and LCR variants remain unchanged from SPEC 4.0. The only changes in SPEC 4.2 occur with ArcTan. We will skip that for
now, though, and focus on the FFT controls and FFT window type. As you can see, the latency test from SPEC 4.0 has been eliminated in this
version. The FFT latency is now compensated for automatically, this makes the latency test no longer necessary.

The default FFT window type has been changed to “Blackman.” In our testing, we have found that Blackman tends to produce a crisper
drum sound, especially when working with ArcTan.

Let’s look at the ArcTan UI in SPEC 4.2:


As you can see, the Rearward Bias slider from SPEC 4.0 has been replaced by three additional sliders for center, front, and rear width. The
rear width slider is dependent on how the first two sliders are set. Utilizing the center and front width sliders, you are able to control how
much of the stereo soundfield ends up in center channel, front channels, and rear channels. For purposes of these controls the stereo is
divided up into 360 degrees. If you were to set the center width at 360 degrees, all the sound would be in the center channel. If you set it for
0 degrees no sound would be in the center channel. You should adjust the center width first, while live monitoring, to determine what sounds
you want in the center (vs. the fronts) and to ensure that no sounds you want only in the center “bleed” into the fronts. Next you do the
same with the front width, determining what is in the fronts, vs. the rears.

This allows for more control over where vocals and instruments are perceived in the mix throughout all five channels.

The other change in ArcTan is that the “Pythagoras” mode in the drop-down menu has been replaced by “Sum” mode. The “Sum” sound
should be similar to “Pythagoras”, but is more mathematically correct.

Everything else in ArcTan remains unchanged. If you’d like more information as to the Adjacent Speaker and Blend controls, please visit the
SPEC 4.0 guide.


LFE Controls

SPEC 4.2 has eliminated the need for the HNM Filter VST in generating an LFE channel by replacing it with a “bass boost” filter which acts
similar to what you would see in a subwoofer amp.

The new LFE “bass boost” consists of 3 stages and an output gain control.

1) A Low Pass filter
a. LFE cross over frequency (usually between 75 and 110 Hz)
b. Crossover Type – the steepness of the crossover filter. 5th order is recommended

2) A “Peaking” filter (default settings shown give you a nice 40 Hz peak)
a. Peak Frequency (usually 40hz)
b. Q – how wide or narrow the peak boost range is (usually set to 1)
c. Bass Peak Filter Gain (Usually 3 dB, set to 0 dB for no peak)

3) A Sub Bass filter
a. Sub Bass cross over frequency (usually 20Hz)
b. Crossover Type – the steepness of the crossover filter. 5th order is recommended

We won’t debate the merits or issues with adding an LFE channel to your surround mix here, but should you choose to do so this new “Bass
Boost” filter is designed to give you a “tighter” “punchier” bass than what was in SPEC 4.0 and earlier.

The new LFE has been set up to be automatically time/phase aligned with the other surround channels, with stages one and two set for 5th
order, regardless of your sample rate. The time/phase alignment may not be correct for One-Pole, One Zero settings.

So there you have it. SPEC 4.2.1. We hope you enjoy the new features!

ZAG 1.7

ZAG stands for “Z Automated Gains.” It is the most streamlined approach to automated channel gain balancing developed yet, requiring
minimal steps on the converter’s part. As a matter of fact, remember that gain spreadsheet Excel sheet from the main SPEC guide and
AutoV2? Feel free to dump that in your Recycle Bin. You no longer need it!

Requirements for the included ZAG layouts:

ReaPlugs VST FX Suite installed from:
And The PeakCompressor VST from:

Open the SPEC421_Free_Mastering_ZAG17.bidule layout. If you see any RED boxes like this:

It means you haven’t installed the VSTs listed in the requirements section, or you didn’t put them where Plogue looks for VSTs.

Now let’s switch to the SPEC421_ZAG17_Relase.bidule layout.

Here’s a look at a SPEC 4.2.1 + ZAG layout, with the new or changed bidules highlighted:


ZAG uses the original stereo (LI and RI) signals to assist in track to track normalization, so those signals must be in sync with the surround
channels coming out of SPEC. The “LI RI Sync” group has been added to take care of that. The first two inputs are for “delay in samples”, the
last two inputs are for “Left In” and “Right In” The outputs are the synced Left and Right channels.

We’ll discuss the limiters and ZAG itself in a moment, but since we’ve added the limiters (which have latency) we need an updated Recording
Control & Delay group as well.

Double clicking on the “Recording Control & Delay group gives you”:


Unchecking the “Gate” box will break the link between the player and the recorder. Checking “Gate” enables the (delayed) link.

Both inputs are for “delay in samples”, however should you need more, remember that you can connect multiple output signals to a single
input in Plogue, and the input will get the sum of the connected outputs.

Another variant of the SPEC 4.2.1 + ZAG layout has the compressors from the Free Mastering group ahead of ZAG:

This is the position in the layout where mastering tools should go (ahead of ZAG). The Free Mastering group doesn’t have any latency but if
you choose to replace it with a mastering tool that does you will need to connect its delay output pin to one of the delay input pins on LI RI

Now let’s get into the details of ZAG.


Like AutoV2 and ARTGC, ZAG is designed to work with a single album-length track. If you are working with individual files for each track on
an album, you can combine them into an album-length track, and create an accompanying Cue sheet, using Foobar2000. Drag and drop
your single song files onto Foobar, highlight them all, and right-click and choose “Convert."


Selecting the “Generate multi-track files” option will create a single album-length file, with an accompanying cue sheet. Obviously, where
you place those files is up to you.

Let’s take a quick look at the top half of the ZAG UI:


What we are going to do is convert the track lengths for each cue point into samples so that ZAG knows where each song begins and ends.
We do this through use of TrackTime6.5. Make sure TT6.5 is kept on your desktop. As with the previous version used with AutoV2, you are
dragging and dropping your cue file onto the TT6.5 icon. This should result:


If you notice, TT6.5 now takes the converted track lengths and copies them onto the clipboard. This saves you some time, since your next
step will be to simple paste those into the “Track Lengths in Samples” box inside ZAG.


Notice how the track # on the bottom now reflects the number of songs on the album. Leave the other measurements on ZAG where they
are for now and go ahead and set up SPEC to the parameters you want for this album. Make sure your album-long track is loaded into the
player as well. Keep ZAG Mode at “Measure Levels” for now and simply hit “Play.” If you see the ZAG meters begin to actually measure
RMS levels, you are good to go. Walk away, make a sandwich, dance with your spouse, etc. Come back when your album is done, hit the
off button, and switch ZAG Mode to “Apply Gains.”

The “Results” box will now show you peak levels, RMS values, and three sets of gains for each track on the album.

The “LGain” is the Level adjustment formula from the spread sheet (Remember the spread sheet?). Each surround channel will (probably)
have a different LGain.

The “NGain” is the track to track Normalization. This ensures that the relative volumes of each surround track are the same as for the
original stereo. Each track will have the same NGain for all channels.

The “FGain” is the Final gain needed to bring the loudest peak of the entire album to the output level you have set in the “Output” box. Every
channel of every track will have the same FGain.

Adding the L, N, and F gains up, and adding those to the RMS value of each channel will give you the normalized output volume level for that
channel. Adding the L, N, and F gains up, and adding those to the Peak value of each channel will give you the output peak level for that
channel. Before, we decide to record, though, let’s go back up to the four boxes below ZAG Mode.

Output refers to where you want to set the highest possible peak value. The range here is -2 to +6. Setting it to zero, or lower, will result in
a fully normalized mix with no positive peak values. However, you may find that your mix is too low in volume, or lacking in power. This is
why our range allows you to the push the highest possible peak value all the way up to +6, and why we include use of a limiter to round that
peak value off at the end of the layout. While excessive use of a limiter is never recommended, when used with some restraint, chances
are what you are rounding off is the rare transient on the album which is not going to negatively affect your overall sound quality.

If using the limiter option, open up the main UI:

Open up “FL Limiter,” which controls the settings for each channel, and make sure your limiter settings look like this:

Pay special attention to the “LookAhead” slider. It should be all the way to the right.

Going back to the ZAG UI, you should now enter your parameters for where you want your center channel, LFE, and rears to be relationally
in volume to one another. What you see above (.8 for center, -10 for LFE, and -3 for rears) is a safe set of defaults for most sources with
most SPEC variants, but you should always feel free to make adjustments according to both source and your own tastes. Once all these
steps are done, you are ready to record your six mono wavs. Now tell me that wasn’t much easier

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