• State
  • Locked Locked
  • Replies 5 replies
  • Subscribers 28 subscribers
  • Views 5739 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPA6120 Headphone Amplifier

Dariusz Kloc
Prodigy 40 points
Other Parts Discussed in Thread: TPA6120A2, OPA2134

Hi,

I found schematic of Headphones Amp:

I would like to build my own version this amplifier, but i don't know why resistors R1 and R12 are in feedback connected to ROUT and LOUT pins. 

What reason is then they are there ;)?

How much it affect on sounds quality?

  • 0
    TI__Guru** 103925 points

    Hi Dariusz,

    Welcome to e2e.
    R1 and R12 are feedback resistors for OPA2134, not for TPA6120A2.
    I think these resistors are used for a compensation network. You may want to ask in the Precision Amplifiers Forum about OPA2134.

    Best regards,
    -Ivan Salazar
    Texas Instruments

  • 0 in reply to Ivan Salazar
    Prodigy 40 points

    Hi,

    Yes they are feedback for OPA2134, but why are connected to output of TPS6120A2? This is not described in TPA datasheet or its EVM....

    How it's affect on sound quality or distortion level?

    I have not found too much connection like this in internet. 

    I try to build configuration socked to put this resistors only to OPA outputs or TPA output, to chceck how it affect on sound.

    Best regards,

    Dariusz K.

  • 0 in reply to Dariusz Kloc
    TI__Guru** 103925 points
    Hi Dariusz,

    I don't know why R1 and R12 are connected to TPA6120A2 output. I would think it should be connected to OPA2134 output. As you say, this kind of feedback is not used in any TPA6120A2 TI design and I don't know who designed the schematic you've uploaded.
    I suggested you to post in Precision Amplifier Forum in case this kind of connection is related to OPA2134 and not to TPA6120A2.

    Best regards,
    -Ivan Salazar
    Texas Instruments
  • 0 in reply to Ivan Salazar
    Prodigy 40 points
    Source is there...(I think) .... blog.audioworkshop.org/.../
  • 0 in reply to Dariusz Kloc
    TI__Guru** 103925 points
    Hi Dariusz,

    Perhaps this opamp is used to alleviate the DC offset at the output of the TPA6120A2. Sometimes this inherent DC offset (about 5mV) produces pop noise.

    Best regards,
    -Ivan Salazar
    Texas Instruments