0
\$\begingroup\$

I need an (for audio bandwidth) all-pass filter that has 0 degrees shift in low frequency and +180 degrees shift at high frequency.

The ones here https://sound-au.com/articles/active-filters.htm (figure 7.5) do just the reverse. All-pass filters from Rod Elliot's site

Can somebody please post a schematic or link to an op-amp based implementation?

\$\endgroup\$
7
  • \$\begingroup\$ Please include the schematic in your post so your readers don't have to follow a link to understand your question. Leave the link there to acknowledge the source. There's an edit link below your question. \$\endgroup\$
    – Transistor
    Commented Jun 12, 2020 at 16:53
  • 4
    \$\begingroup\$ +180 at high frequencies is non-causal. If you really need to do this, you'll just have to run time backwards. (Consider if there's a way to approximate what you need with the classic all-pass you found and an inverter). \$\endgroup\$
    – user16324
    Commented Jun 12, 2020 at 16:53
  • \$\begingroup\$ @BrianDrummond It might not be the first time I meet someone meaning to say -180, instead of the +180. Maybe OP meant it negative? \$\endgroup\$
    – a concerned citizen
    Commented Jun 12, 2020 at 21:25
  • \$\begingroup\$ @aconcernedcitizen if that were so, the linked solution would suit his purpose. \$\endgroup\$
    – user16324
    Commented Jun 13, 2020 at 10:18
  • \$\begingroup\$ @wonderfullot. I rejected your edit of my post as you were trying to start a conversation in my post. That's not how this site (or any other site I've ever seen) works. My post is now deleted. \$\endgroup\$
    – Transistor
    Commented Jun 13, 2020 at 15:09

0

Reset to default

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.