Radio Design Labs TX-8A
4/8 Ohm Input Interface


Our Price: $72.98
List Price: $97.62
You save 25%!

5.0 / 5

★★★★★ 1 Review. Write Yours
Radio Design Labs TX-8A
In Stock

Related Products

Radio Design Labs' TX-8A is a great choice in many applications requiring superior quality transformer coupling between the output of a 4 or 8 Ohm power amplifier and the input of an audio mixer or amplifier.  A front-panel LEVEL control allows the output to be adjusted for -10 dBV or +4 dBu over a wide range of amplified power levels.

The TX-8A is a single-channel (mono) module featuring barrier block connections for the input and output.  A high quality bifilar wound audio transformer couples the audio input to the audio output.  The amplified input terminals are isolated from ground.  The output ground terminal is connected to the TX-8A metal support structure.

The audio transformer provides galvanic isolation.  The secondary may be wired balanced or unbalanced.  The TX-8A delivers the wideband audio, low distortion, audio clarity and headroom common to professional equipment in a module suited to general-purpose audio installations

The excellent low frequency response makes the TX-8A well suited to feed the line-level input of a subwoofer amplifier.  In a stereo installation, two TX-8A module output may be mixed to feed a mono audio line and/or a subwoofer amplifier line input.

The TX-8A's compact size permits mounting in a variety of spaces and in various locations in equipment racks.  The TX-8A may be mounted where needed, to rack sides or in an equipment rack (either the front or rear rack rails) using a variety of available RDL mounting options. Use the TX-8A individually, or combine it with other RDL products as part of a complete audio/video system.


  • Converts an Amplifier Output to Line Level
  • Bridges 4 or 8 Ohm Speaker Line
  • Adjustable for Wide Range of Input Power Voltage
  • Converts Amplified Levels from 0.5 W to 400 W
  • Excellent Low Frequency Response
  • Suitable to Feed a Subwoofer Amplifier Input
  • Detachable Terminal Block Connections
  • Balanced or Unbalanced Output
  • Superior Quality Audio Transformer
  • Bifilar Windings
  • Galvanic Isolation
  • Convenience of RDL TXs


  • Input Connector: Barrier block
  • Minimum Input Level* (for +4 dBu Output): 8 W (8 Ohms); 16 W (4 Ohms)
  • Minimum Input Level* (for -10 dBV Output): 0.5 W (8 Ohms); 1 W (4 Ohms)
  • Maximum Input Level*: 400 W
    *Input level is the voltage that corresponds to a 4 Ohm or 8 Ohm amplifier output
  • Attenuation Range: 16 dB to 34 dB (input to output)
  • Output Connector: Barrier block
  • Output Level: -10 dBV unbalanced or +4 dBu balanced, adjustable (10 kOhm load)
  • Galvanic Isolation: Bifilar wound audio transformer
  • Frequency Response: 20 Hz to 20 kHz (+/- 0.75 dB)
  • THD: <0.1% (1 kHz); <1% (20 Hz to 20 kHz)
  • Power Requirement: Passive
  • Dimensions:
    Height: 3.0 in. 7.6 cm
    Width: 1.2 in. 3.0 cm
    Depth (case): 1.5 in. 3.8 cm
    Depth (with connector): 1.8 in. 4.6 cm

5.0 / 5


Reviewed by 1 customer.
(1 is a Verified Buyer.)

Write a Review

Display Only Verified Reviews


There are no reviews to display with the selected filters.

Ron S on 11/03/2017 ✔ Verified

I have implemented RDL products in our Two-Way radio Public Safety designs for years. All RDL Products perform as described and are professionally designed and engineered. Thanks RDL for great inventions turned into a great product. Ron.

0 Comments / Add a Comment

This cannot be empty.
This cannot be empty.
This cannot be empty.
Please Enter your First Name Please Enter your Last Initial
This cannot be empty.

500 characters remaining

Please Enter your Feedback

Thank you for submitting your comment. It is in a queue to be moderated.

Add to Cart

We're sorry, only of this item available

Call a Sales Pro at 800-356-5844 for more information