Relationship of Normalize to Graphic Equalizer filter?

[tketcham]

Hello,

I've been using Vinyl Studio to de-click and normalize pre-recorded LP WAV files (one file for both sides) and was wondering if someone could explain the relationship of the Normalize function and the Graphic Equalizer filter? It doesn't seem very clear as to how Normalize is incorporated into the process. (I tried searching but did not find the answer I was looking for.) Specifically, is Normalize a sub-routine of the Graphic Equalizer filter or is Normalize a stand-alone process, independent of the filters, or can it be run either way?

Here are some screen captures that might help explain what I'm wondering about. (Ignore the Presets entry.)

All filters OFF, Normalize not run:



Normalize run at -3dB, Graphic Equalizer ON:



Question: When Normalize is run, does that automatically turn on the Graphic Equalizer filter with the normalization boost included as part of that filter? For example, if I save a series of custom filter presets with a range of normalization settings, when I run one of the filter presets as part of the Save Tracks routine, will normalization occur as part of the custom filter? No need to run Normalize as a separate process?

Normalize run at -3dB, Graphic Equalizer OFF:



Question: Does turning the Graphic Equalizer OFF also defeat the normalization boost? I'm not sure why a custom preset like this would be saved. For example, if I ran Normalize during the save process and then ran a custom filter preset with Graphic Equalizer turned OFF, would that undue the normalization boost?

And lastly, when saving a file, if I run a custom filter preset that includes Normalize as part of the Graphic Equalizer filter and also run Normalize, does the file get normalized twice (additive) or is any normalization always applied to the original WAV recording (plus any de-clicking)?

I'm a relative beginner at using Vinyl Studio and therefore still learning the nuances of the software, but it seems to me that Normalize should be a separate filter function (with its own tab) and not included as part of the Graphic Equalizer filter. That would remove any confusion.

Hope my questions make sense and thanks for any clarification.

Regards,
Tom

[Paul Sanders (AlpineSoft)]

Hi,

The way that Normalisation works in VinylStudio is actually quite simple, once you understand it, but perhaps a bit subtle.

Because VinylStudio doesn't want to alter the original recording, it has to 'remember' the gain that needs to be applied so that it can apply it later when saving your tracks.  It does this by adjusting the preamp sliders in the Graphic Equaliser at the end of the scan.  It therefore follows that the Graphic Equaliser needs to be turned on in order for the scan to take effect and VinylStudio does that automatically for you.

The answers to the rest of your questions really follow from this:

> Is Normalize a sub-routine of the Graphic Equalizer filter or is Normalize a stand-alone process, independent of the filters, or can it be run either way?

It's a bit of both.  It's a standalone process in that it scans the input file to work out the required adjustment, but it's connected to the filters in that the preamp sliders fulfill (or can fulfill) a dual role.  You can set them to what you like, but normalising sets them to something sensible.

> When Normalize is run, does that automatically turn on the Graphic Equalizer filter with the normalization boost included as part of that filter?

Yes.

> For example, if I save a series of custom filter presets with a range of normalization settings, when I run one of the filter presets as part of the Save Tracks routine, will normalization occur as part of the custom filter? No need to run Normalize as a separate process?

You have to run a scan for each recording to determine the amount of boost (or cut) needed for that recording.  Saving your settings as a preset won't help you in this regard.  There's a batch normaliser that can operate on several albums on one go in the Save Tracks / Batch window.

> Does turning the Graphic Equalizer OFF also defeat the normalization boost?

Yes (because it also disables the preamp sliders), but this would only happen if you did it explicitly.  Having all the other Graphic Equaliser controls set to 0dB provides a clean signal path through the equaliser, so turning it on does no harm.

> When saving a file, if I run a custom filter preset that includes Normalize as part of the Graphic Equalizer filter and also run Normalize, does the file get normalized twice (additive) or is any normalization always applied to the original WAV recording (plus any de-clicking).

Normalisation is not cumulative.  Any scan you run will 'forget' the original setting of the preamp sliders.  It will be applied to the original recording, with the proviso that if you have applied any *other* filters (such as the Graphic Equaliser itself,  perhaps a bit of hiss filtering and treble boost for a tape) then these will be taken into account.  In other words, Normalise will always 'do the right thing' in these circumstances.

[tketcham]

Paul, thank you for the quick reply!

I can see the logic in how normalize is incorporated into the filters so I'll treat it as a sub-routine of the filtering process. That is, I probably won't start out using custom filters that include preamp gain presets; I'll run Normalize each time. But I can see that after running normalize for a range of LP recordings I'll have a fairly good sense of what preamp gain settings correspond to various levels of normalization for a given LP recording. That is, I could use custom filters that include appropriate preamp gain settings and not have to run Normalize separately. Is that correct/make sense?

Thanks again!
Tom

PS: I use the USA spelling ("normalize") rather than the British spelling ("normalise") because of habit and not insistence. '-)

[Paul Sanders (AlpineSoft)]

Sure, no problem.  Two peoples divided by a common language.

I would normalise each time, myself.  Then you know there won't be any clipping.  Like I say, you'll find a batch procedure in the Save Tracks / Batch window.  It's hiding under the More button, but a scan only takes a few seconds anyway.  For reasons already given, do it (or do it again) after all other audio cleanup is complete.

[MyKart]

I have another related question regarding Normalise. Rather than create another thread I'm piggy-backing onto this one. I hope that's okay.

One of the options with Normalise is to process right and left channels separately. Does that not diminish or change, to an extent, the stereo effect of the original mix?

[Paul Sanders (AlpineSoft)]

Well, change it, certainly, but we provide this feature to correct the imbalance that some sound cards have between the left and right channels when recording.

But it can, of course, be fooled, and perhaps a better way of correcting such an imbalance is to set up a preset with the preamp sliders set appropriately.

[MyKart]

Thanks Paul,
Is that feature geared more for PCs than Macs then?
I noticed that with the Rumble filter on, I'm still getting some amount of clipping (although not as much as with MC23) on portions of files that were recorded with peak levels at around 80 or below so, I've made Equalisation part of my recording routine but, am getting varying results between left and right channels. For instance, sometimes the left will be -3 and the right will be +1 (or thereabouts) so, I've been tweaking them toward the middle of that range so I end up with something like -1 on the left and 0 on the right (for instance), thinking that some of those differences between l & r are intentional.
I've been selecting a portion of the file that has the highest peaks and manually tweak the Equalisation results up or down until I get no clips in that sample. Is there processing going on behind the scenes with Equalisation other than just the Pre-amp levels?
Sometimes results are reversed, IE - the right will be -3 and the left +1. Each recording is different so I don't know how to create preset to contend with that.
MC-24, OS 10.13.4.

[Paul Sanders (AlpineSoft)]

No, not really, the imbalance can occur in any digitising hardware.  I use the term 'sound card' loosely.

Given the results you're getting, this doesn't appear to be a very useful feature.  I would normalise with the channels paired and then adjust any imbalance by ear (reduce the louder channel rather than boosting the quieter one when you do that to avoid introducing clipping).

All that Normalisation in VinylStudio does is to adjust the preamp sliders.  The only vaguely clever part is the 'ignore transients' box, which attempts to ignore outliers to give more accurate results at the expense (sometimes) of slight clipping.

[MyKart]

Oops. I got my betas mixed up I meant to say VS 9.0.

[MyKart]

Thanks for that info.. I'll play with the transients option which, has been selected up until now. Maybe I worry about clipping too much. I don't recall having a problem with it until switching from a MM cart. to a MC.

[Paul Sanders (AlpineSoft)]

OK, thanks.  Changing cartridge would affect your recording level, certainly, but then I think most people set that for each LP they record anyway.

[MyKart]

Yes, it's definitely an album by album process. I first noticed it with Sgt. Peppers which has more stereophonic differential between L&R channels than most, I suppose. My typical rec-level with an MM cart. was anywhere from 71 all the way up to 100, in a few instances. With an MC cartridge, it's 21-29. With the MM I tried to peak-level at no higher than 85 or so when recording. Since switching to the MC cart. and noticing the Rumble-filter tending to clip, I have taken my recording-level down a notch further to hover around 70 which seems to nullify the Rumble/clip-issue and leaves plenty of headroom for any processing during playback in other software. Normalising seems to work best for me when it's on the + side.

[Paul Sanders (AlpineSoft)]

To get the most headroom, record at 24 bit if your sound card supports it (you can check via the 'Show Sample Rates' button in VinylStudio's Check Level dialog).  Then the recording level doesn't matter so much as you can always boost it after recording without losing dynamic range.

Also, consider recording to FLAC to save disk space.  This is compressed but lossless, and you can still save your tracks in whatever format you want.

[MyKart]

I've been using WAV to record art 24-bit and then save-as FLAC. I did switch to 32-bit when the beta came out but, will switch back to 24-bit and see how that affects things.
Paul - Although I only just registered in this forum, I have been using VS for several years. It has provided me with many many hours of happiness. Thanks man.

[Paul Sanders (AlpineSoft)]

OK, thanks.  I would not go above 24 bit - your sound card will be limited to that anyway, and recording to FLAC will save you some disk space without costing you anything (apart from a few CPU cycles).

VinylStudio can do batch file format conversions in the Save Tracks / Batch window, in case you find that useful.