• State Resolved
  • Locked Locked
  • Replies 6 replies
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 1293 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.

TAS5782M: 3-Band DRC Structure

Sadanori Kato
Guru 36520 points
Part Number: TAS5782M

Hi,

Could you please tell me whether the following DRC structure is same with 3-Band DRC which is embedded in TAS5782M ?

TAS57xx Dynamic Range Control
http://www.ti.com/lit/an/sloa148/sloa148.pdf

Best regards,
Kato

  • 0
    TI__Mastermind 24835 points
    Hi Kato-san,
    That document is very old and based on TAS570x~TAS571x. DRC stucture is very similar between it and TAS5782M, but there is a little difference, e.g. TAS5782M has k0~k2 parameter while TAS570x/TAS571x only has k0 and k1 parameter.... Even though, this doucment is a good material to help customers to understand how DRC works.
    Best regards,
    Shawn Zheng
  • 0 in reply to Shawn Zheng
    Guru 36520 points

    Hi Shawn-san,

    Thank you for your prompt reply.

    I should inform the detailed information from our customer, so could you please share the application note for TAS5782M 3-Band DRC if possible ?

    Best regards,
    Kato

  • 0 in reply to Sadanori Kato
    Guru 36520 points

    Hi Shawn-san,

    Sorry for rushing you, so please let me know if you have any updates on this issue.

    Best regards,
    Kato

  • 0 in reply to Sadanori Kato
    Guru 36520 points

    Hi Shawn-san,

    Could you please tell me the detailed information as below ?

    Best regards,
    Kato

  • 0 in reply to Sadanori Kato
    TI__Genius 9995 points

    Hi Kato-san,

    Detailed information of 3-band DRC structure related with PPC3 is as bellow:

    As can be seen above, 3-DRC structure of TAS5782 can be divided into three main part:

    1. Corssover: for each band, a 2th order BQ is used;
    2. Adv DRC: include three parts in general:
      1. Energy muxing: it is used to estimate the energy of L/R channel. The opening parameter is Energy time constant. It can determine time window calculating the estimated L/R energy;
      2. Region response: as can be seen above, threshold, offset and ratio can be configured to achieve DRC curve you want; Further, after audio signal pass the curve, attack/release structure is used to smooth the whole change when attack or release behavior happens;
    3. mixer gain: usually it is set to be 1 in default. Since filters may affect phase, a phase reversal or a 180 degree phase shift may be necessary, which calls for using a negative sign on the coefficient to reverse the phase for the second-order filter.

    Regards,

    Alix Wan.

  • 0 in reply to Alix Wan
    Guru 36520 points

    Hi Alix-san,

    Thank you for the detailed information.

    I understood, so I will contact you if I get additional questions from our customer.

    Best regards,
    Kato