1 5
IGS AUDIO

T4Bx

Outboard Parts

Matched T4B-style photocell, 10ms attack, 60ms release (50%), 20Hz–20kHz response, ideal for LA-2A, LA-3A, and IGS opto compressors, ensures consistent compression

$198.00 CAD
Shipping calculated at checkout.
Talk to our experts
Our team of experts is here to support you.

Delivery & Shipping

Free Shipping in Canada with orders over $200. Conditions apply. View details here.

Financing

Affirm

Break your purchase into easy monthly payments, quick approval and no hidden fees.
Click here for more info.

Equilease

Ideal for larger purchases, Equilease offers customized leasing solutions to fit your business needs.
Click here for more info.

Returns & Policy

You can review our terms and conditions here

Description

The IGS Audio T4Bx is a modern, precision-engineered optical photocell module designed as a direct replacement for the classic T4B found in vintage-style optical compressors like the Teletronix LA-2A, LA-3A, and their modern counterparts. Staying true to the legacy of the original design while solving the inconsistencies often found in vintage units, the T4Bx offers remarkable component consistency and matched performance, making it ideal for both stereo and mastering-grade applications where phase alignment and sonic symmetry are critical.

At the heart of its performance is a carefully calibrated electroluminescent panel and photoresistor combination, developed by IGS Audio to replicate the unique compression characteristics of the original T4B smooth, musical gain reduction with classic LA-2A-style behavior. With fixed time constants of approximately 10ms attack and 60ms release to 50%, the T4Bx provides a familiar, reliable compression curve across every unit, ensuring predictable performance whether you're replacing a single module or outfitting a stereo pair.

Fully compatible with IGS Audio's own One LA500 and One Leveling Amplifier, as well as with original Teletronix LA-2A and LA-3A compressors, the T4Bx invites users to experiment and fine-tune their signal path with the assurance of repeatable, high-quality results bringing modern consistency to a classic sound.

Features

Modern Take on a Classic Component
Designed as a precise, high-quality replacement for the original Teletronix T4B photocell used in legendary optical compressors.

Consistent and Matched Performance
Individually tested and selected components ensure minimal variation across units for reliable, repeatable results.

Authentic Optical Compression Feel
Preserves the smooth, musical response of vintage LA-2A-style compressors with improved consistency.

Compatible with Iconic Compressors
Drop-in replacement for T4B in units like the LA-2A, LA-3A, IGS One LA500, and One Leveling Amplifier.

Reliable Attack and Release Behavior
Delivers classic 10ms attack and smooth 60ms release (to 50%), ideal for vocals, bass, and more.

Full-Range Audio Transparency
Maintains a wide frequency response from 20Hz to 20kHz for natural, open sound.

Specifications

General Specifications
Device Type: Optical Compression Photocell Module
Model: T4Bx
Application: Compatible with IGS One Leveling Amplifier, IGS One LA500, Teletronix LA-2A, LA-3A
Design: Electroluminescent Panel with Matched Photoresistors
Interchangeability: Compatible with Original Teletronix T4B

Time Constants
Attack Time: 10 ms
Release Time: 60 ms (for 50% Release)

Performance
Frequency Response: 20 Hz – 20 kHz

Usage
Function: Optical Element for Dynamic Range Compression
Purpose: Improved Consistency in Stereo Image and Compression Behavior through Component Matching

Payment & Security

  • American Express
  • Apple Pay
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Back to top