SOLID STATE LOGIC B-DYN Module

Product overview

The SOLID STATE LOGIC B-DYN Module puts the dynamics processor of the SL 4000 B console channel strip into 500-series format: heavily coloured, grabby, saturated compression with a de-esser mode and a gate / expander, from one of the rarest studio consoles ever made.

The 4000 B Dynamics module was responsible for countless iconic records with characterful compression on drums and vocals. The dynamics section of the SL 4000 B console channel strip was unlike any SSL channel dynamics module that followed: it used the fader VCA as its gain element rather than a dedicated VCA, in a design similar to the topology of the SSL Bus Compressor. B-DYN inherits this VCA feedback design, offering coloured compression with its own unique sonic signature, very different from the later E and 9000 Series, and an Auto release with a programme-dependent release time as found on the Bus Compressor.

Key features

• Authentic recreation of the SL 4000 B console dynamics processing
• Design based on the SSL Bus Compressor
• Compressor / limiter and gate / expander
• Feedback design with peak sensing for an aggressive 'grabby' character
• Fixed compression ratios 2:1, 4:1 and 10:1 with an additional DS (de-esser) mode
• Fixed release times DS, 0.2, 0.4, 0.8, 1.6 s and the renowned Auto
• Auto make-up gain
• Side-chain high-pass filter
• Stereo LINK mode

Compressor / limiter

RATIO offers stepped ratios of 2:1, 4:1, 10:1 and DS; OUT bypasses the compressor. THRESH (+10 to -20 dB) sets the level above which compression starts and also provides automatic make-up gain; its linearity has been slightly improved over the original channel strip control to help tuning with the smaller 500-series knobs. A 6 dB/octave 185 Hz high-pass filter in the side chain helps reduce bass pumping. RELEASE is switched between 0.2 and 1.6 s with DS and AUTO options, and the attack is about 30 ms.

De-esser (DS) mode

With RATIO and RELEASE set to DS, the module is optimised for reducing sibilance: a 10:1 ratio with the side-chain signal filtered at about 7 kHz gives broadband compression triggered by sibilance. The DS release varies with the signal between 30 and 50 ms, much faster than usual for an SSL dynamics section, and the attack drops to 2 ms. The two DS settings work independently, so the fast DS time constants can be used without the DS ratio for aggressive compression.

Gate / expander

The gate / expander acts as a 20:1 gate, or as a 2:1 expander with a gentle curve when EXP is pressed. RANGE sets the maximum gain reduction (OUT bypasses it), THRESH the level above which it opens, and RELEASE (0.1 to 1.6 s) how long the signal stays audible after it closes. Attack is a fast 0.2 ms.

Metering and stereo LINK

Two LED columns show compressor and gate activity, and IN switches the whole module in or out. LINK sums the side chains of a pair of modules in racks whose back-plane provides a link connection: the module changing gain the most applies the same gain to its partner, preventing image shifts on stereo material.

In the box

• B-DYN Module (500-series)

SOLID STATE LOGIC B-DYN Module: frequently asked questions

What makes B-DYN sound different?

It uses a VCA feedback design similar to the SSL Bus Compressor, with peak sensing, giving coloured, grabby compression very different from the later E and 9000 Series.

Can it de-ess vocals?

Yes. Set RATIO and RELEASE to DS for 10:1 compression triggered by sibilance through a 7 kHz side-chain filter.

Can two modules work as a stereo pair?

Yes, with LINK, in a 500-series rack whose back-plane provides the link connection.

Does it have make-up gain?

Yes. THRESH provides automatic make-up gain.

Where can I buy the SOLID STATE LOGIC B-DYN Module in India?

The SOLID STATE LOGIC B-DYN Module is available from Shivansh Electronics, Kolkata, West Bengal, India, with delivery across India.

Workflow 1: Characterful drums

Producers wanting grabby drum compression.

Connections

Setup

1. Set RATIO 4:1.
2. Set RELEASE to AUTO.
3. Lower THRESH for heavy colour.
4. Use the side-chain HPF on kick to limit pumping.

Tip: The fast DS attack / release gives even more aggression.

Workflow 2: Vocal compression

Mixers adding colour to vocals.

Connections

Setup

1. RATIO 2:1 or 4:1.
2. Release 0.4-0.8 s.
3. Set THRESH for a few LEDs.
4. Compare with IN.

Tip: Make-up gain follows the threshold automatically.

Workflow 3: De-essing

Taming sibilance.

Connections

Setup

1. Set RATIO to DS.
2. Set RELEASE to DS.
3. Lower THRESH until the esses are controlled.
4. Check with IN.

Tip: DS release varies between 30 and 50 ms.

Workflow 4: Gating toms

Cleaning up drum mics.

Connections

Setup

1. Set RANGE.
2. Raise THRESH until spill is gated.
3. Set RELEASE to the tom decay.
4. Bypass the compressor with RATIO OUT if not needed.

Tip: Attack is a fast 0.2 ms.

Workflow 5: Expanding noisy sources

Guitar amps or room noise.

Connections

Setup

1. Press EXP.
2. Set THRESH below the playing level.
3. Set RANGE for the noise reduction.
4. Adjust RELEASE.

Tip: The 2:1 expander curve is gentler than the gate.

Workflow 6: Stereo bus colour

Two modules on a stereo group.

Connections

Setup

1. Fit the pair in a link-equipped rack.
2. Press LINK on both.
3. Match settings.
4. Set the threshold.

Tip: The pair applies the same gain, keeping the stereo image.