Bundle of Audio Transformers Adaptors for Mics (MIT-129, 274-017c, 274-016C)

Bundle of Audio Transformers Adaptors for Mics (MIT-129, 274-017c, 274-016C)


Jeff Got scammed a few times - Luckily he found SpenCertified!

This is a great bundle of audio connectors / transformers / adaptors that are perfect custom "pro" audio hookups!

The Hosa MIT-129 adapter is designed to match 50K output impedance to 200R input impedance. It is best for connecting a hi-Z instrument to a microphone input.

The Radio Shack 274-017c 1/4" Jack-to-A3M XLR Plug Adapter/Transformer can be used to connect a high-impedance guitar cable to a balanced, low-impedance input.

The RadioShack 274-016C is a practical line matching transformers that can be used to get your mic and audio equipment in sync so you can achieve the right impedance for your particular mic.


We have cleaned it inside and out and replaced any worn parts. 

Cosmetic Condition: Very Good.

Functional Condition: Very Good.

What’s in The Box?

  • Four (4) Hosa MIT-129 1/4" TS to XLR3M Impedance Transformer
  • Three (3) RadioShack 274-017c Microphone Adapter
  • One (1) RadioShack 274-016C Transformer Adaptor


  • Left Connector(s): 1 x phone stereo 6.3 mm - female
  • Right Connector(s): 1 x 3 pin XLR - male
  • Product type: Audio adapter
  • 200 ohms - 50K ohms
  • Maximizes signal fidelity when using impedance mismatched gear
  • Minimizes high frequency and level loss caused by signal reflections
  • Eliminates noise and hum caused by an impedance mismatch
  • Connectors: 1/4 in TSF to XLR3M


  •  Lo-z/Hi-z 1/4" F & XLR (3-Pin) Male


  • 274-016C
  • Hi-Z Unbalanced
  • Lo-Z Balanced Transformer
  • Inputs: 1/4" Male
  • Outputs: XLR 3 Pin Stereo Female
    Impedance: High-Z unbalanced 1/4" to low-Z balanced A3M, rated 30K ohm to 600 ohm

    Customer Reviews

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    Customer Since December 2017

    I have always been impressed with the items I received even after a couple years they continue to work. This is the reason why I always keep returning as a customer.

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