Getting the most out of the SPL Tube Vitalizer

In this article I’m going to share some analysis insights but also proposing an easy to follow 3-step approach for finding the sweet spot while processing any kind of material with this device.

Preparing for winter season: room heating with style

So, having now a Tube Vitalizer here on my desk (at least for some time), I was surprised about the lack of usable online reviews and background information. One just finds the usual YT quality stuff which might be entertaining in the best case but also spreads misinformation ever so often. To save those influencers honor it must be said that the Vitalizer concept is really not that easy to grasp and its quirky user experience makes it not easier. The manual itself is a mixed bag since it contains some useful hints and graphs on the one hand but lots of marketing blurb obscuring things on the other. Time to clean up the mess a little bit.

What it actually does

While easily slotted into the “audio exciter” bucket, some more words are needed to describe what it actually does. Technically speaking, the Vitalizer is basically a parallel dynamic equalizer with an actual EQ curve behaviour which aims to mimic equal loudness contours as specified in ISO226. Rather simplified, it can be seen as a high and low frequency shelving EQ to dial in a basic “smile” EQ curve but one which takes hearing related (psychoacoustic) loudness effects into account. It does this also by generating curves differently based on signal levels, hence the term “dynamic EQ”. And wait, it also adds harmonic content galore.

Taming the beast

To obtain an equal loudness contour the main equalizers center frequency must be properly set depending on the tonal balance of the actual source material. This center frequency can be dialed in somewhere between 1k and 20kHz by adjusting the Hi-Mid Freq knob which defines a cross-over point: while frequencies below that point gets attenuated, the higher frequencies gets boosted. However, this attenuation is already a signal level dependent effect. Opposed to that, the LF EQ itself (which actually is not a shelving but a bell type curve) has a fixed frequency tuned to 50Hz and just the desired boost amount needs to be dialed in. The LF curve characteristic can be further altered (Bass soft/tight) which basically thickens or thins out the below 100Hz area. Finally, this EQ path can be compressed now with the Bass Comp option.

A typical EQ curve created by the Vitalizer

On top of the main EQ path, the Tube Vitalizer offers an additional HF boost and compression option which both can be dialed in to complement the LF behaviour in a very similar fashion but in the high frequency department. Internally, both are in a parallel configuration and mixed back into a dry signal path. The according Process Level knob can be seen as a kind of dry/wet option but only for main the EQ part. The upper HF part is mixed back in separately by the Intensity dial.

Gain-Staging is key

For the EQ section as a whole, the Drive knob is the ticket for proper gain-staging. If compression can be dialed in properly for both compressors (as indicated by the blue flashing lights) input gain is in the right ballpark. One might expect to hear actual compression going on but it appears to be a rather gentle leveling effect.

Gain-staging for the output stage has to be concerned separately which might become an issue if the tube stage is activated and operates in shunt limiting mode. Now you have to take care about proper input levels since the Attenuators for both output channels are operating after the limiter and not beforehand.

Tube stage limiting: input (red) vs output (blue)

Which directly leads us to the additional harmonic content created by this device. First of all, there is always additional harmonic content created by this device, no matter what. One might expect the device to not show any such content with the solid state output stage but it actually does. The tube output stage just increases that content but signal level dependent of course and 2nd order harmonics are always part of that content. A serious additional amount of harmonics gets added as soon as the HF filter gets engaged by dialing in Intensity (and LC Filter mode activated!) but this sounds always very smooth and natural in the top end, surprisingly.

Delicious content

Also impressive is the low noisefloor for both output stage modes, tube and solid state. The first one introduces pretty strong channel crosstalk, though.

Workflow – Finding the sweet spot in 3 easy steps

Initial condition:

  • Drive, Bass, Bass Comp and Intensity set to 0
  • Device is properly gain-staged

1. Set Process to 5 and now find the best fit for Hi-Mid Freq for the given source material. For already mixed 2bus stuff you can narrow it down to 2-3kHz most likely.

2. Dial in Bass (either left or right depending on source and taste) and some compression accordingly.

3. Only then dial in some further HF content via Intensity and some compression accordingly. Adjust HF Freq so it basically fits the source/taste.

Workflow – Tweaking just one knob

My good old buddy Bootsy told me this trick which works surprisingly well.

Initial condition:

  • Left most position: Bass
  • Right most position: Bass Comp, High Comp, High Freq
  • 12-o-clock position: Drive, Intensity
  • Hi-Mid-Freq set to 2.5kHz

Now, just dial in some (few) Process Level to taste.

He also recommends to drive the input to some extend (VU hitting the red zone) using the Tube stage in limiter mode while always engaging LC Filter mode for HF.

out now: SlickEQ “Gentleman’s Edition”

SlickEQ_German

Key specs and features

  • Modern user interface with outstanding usability and ergonomics
  • Carefully designed 64bit “delta” multi-rate structure
  • Three semi-parametric filter bands, each with two shape options
  • Five distinct EQ models: American, British, German, Soviet and Japanese
  • Low band offers an optional phase-lag able to delay low frequencies relative to higher frequencies
  • High pass filter with optional “Bump” mode
  • Low pass filter with two different slopes (6dB/Oct and 12dB/Oct)
  • Parametric Tilt filter with optional “V” mode.
  • Six output stages: Linear, Silky, Mellow, Deep, Excited and Toasted
  • Advanced saturation algorithms by VoS (“Stateful saturation”)
  • Highly effective loudness compensated auto gain control
  • Stereo, mono and sum/difference (mid/side) processing options
  • Frequency magnitude plot
  • Tool-bar with undo/redo, A/B, advanced preset management and more

SlickEQ is a collaborative project by Variety of Sound (Herbert Goldberg) and Tokyo Dawn Labs (Vladislav Goncharov and Fabien Schivre). For more details, please refer to the official product page: http://www.tokyodawn.net/tdr-vos-slickeq-ge/

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compressor aficionados (9) – D.W. Fearn

Doug, when and how did you arrived in the music business?

I have had an interest in electronics ever since I was a kid growing up in the 1950s and 1960s. I built a crystal radio  receiver when I was 8 and my first audio amplifier (tubes, of course) when I was 10. I passed the test for an amateur radio license when I was 12 and that experience of communicating using Morse code was excellent training for  learning to hear. I built a lot of my own radio equipment, and experimented with my own designs.

The high school I attended had an FM broadcast station. Most of the sports and musical events were broadcast, and I learned about recording orchestras, marching bands, choirs, and plays. Friends asked me to record their bands, which was my first experience working with non-classical music.

Another major factor was that my father was a French horn player in the Philadelphia Orchestra. As a kid, I would attend concerts, rehearsals, and sometimes recording sessions and broadcasts. I learned a lot about acoustics by walking around the Academy of Music in Philadelphia during rehearsals.

It would seem logical that my musical exposure and my interest in electronics would combine to make the career in pro audio I have had for over 40 years now.

I was a studio owner for many years before starting the D.W. Fearn manufacturing business, which started in 1993. [Read more…]

ThrillseekerLA explained

What is needed to get clear from the start is that every compressor will sound different, the controls will act differently, and some will be better at doing certain types of compression than others. While the basic controls like ATTACK and RELEASE will have a similar function, the resulting change to the sound may be totally different.

David from www.learndigitalaudio.com has made a deep and comprehensive article about compression and ThrillseekerLA. Don’t miss to read the whole thing over there at his site which contains lots of examples and explanations. Theres also a PDF document available.

ThrillseekerLA 1.0.1 update available

ThrillseekerLA_open

Changelog for Release 1.0.1

  • Stronger 2nd and 3rd harmonics added in the interstage
  • Link algorithm revised and simplified
  • SC lowcut filter revised

The update is available in the downloads section.

 

major mkIII update for Density bus compressor released

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announcing Density mkIII – providing depth and dimension, mastering grade

As hinted earlier in a facebook post, the TesslaPRO update will be delayed and probably released after the summer break – it is just not there yet. Instead, a major update for the Density compressor plug-in already made it and it will going to see the light somewhere later this month.

So, lets talk about the Density mkIII update. During the last two years or so I’ve received quite a lot of feedback to the Density mkII release – mostly coming from mastering engineers – on how to improve its dynamic response towards todays mastering needs. Some very early efforts did not made it but with the learnings from the ThrillseekerLA compressor design and the emerging stateful saturation approach everything was possible, all of a sudden. [Read more…]

BootEQ mkII updates to version 2.1

… and finally adds support for higher samplerates.

BootEQ mkII - analog style equalizer and pre-amp simulator

Release notes:

  • support for higher samplerates
  • faster loading times on systems with large amounts of system fonts
  • VST vendor tag changed to “Variety Of Sound”
  • stability improvements when deleting the plug-in from effect slots
  • stability improvements in cubase hosts
  • VU display issue on mono tracks fixed
  • less CPU consumption if GUI is closed
  • slightly increased 2nd order harmonic in “TUBE ON” mode
  • resetting the DRV knob with <ctrl>+click w/o any audio artifacts now
  • reset position for the left LF frequency knob corrected to 250Hz
  • audio crackles while switching preamp section on/off eliminated
  • improved HF shelving filter with freq dip and asymetric behaviour
  • changed pop-up displays version number now
  • some EQ code optimizations added
  • preset and manual update

Known issues:

  • some display/knob rendering issues mainly in samplitude (compiler bug)

BootEQ mkII is available as freeware for Win32 and VST compatible systems – to download just refer to the download page or just click here instead and please acceppt the end-user license agreement.

Additional links:

NastyVCS – I can has color

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NastyVCS – I can has dynamics

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