[sdiy] r/c phase shift on face (esoterica could save the pie)

[Magnus Danielson]

From: Anthony Bisset <abisset at dspaudio.com>
Subject: Re: [sdiy] r/c phase shift on face (esoterica could save the pie)
Date: Wed, 18 Apr 2007 05:01:39 -0700 (PDT)
Message-ID: <Pine.LNX.4.58.0704180454550.5352 at fourier>

Anthony,

> so, 1:1 audio transformer wired reverse polarity will give us 180 degrees
> consistently across all frequencies (degradation notwithstanding)?

Indeed. An op-amp (say NE5534) and two resistors (say 47 kOhm) will do the same
job but much cheaper.

> if a dome filter is the only way to get 90 then this is becoming a
> question of how bawdly i want an exact phase shift. as i imagined having
> each module (count is now around 60) with a 90degree phase shifted
> output, i may  have to rethink or compromise.

Certainly. The dome filters is indeed one of the costs and places where
compromises occurs. The Polyphase filters may have a very attractive cost.
Do look at them! Interesting interconnections of resistors and capacitors,
with suitable buffers in and out.

> thanks for the suggestions!

Anytime!

Cheers,
Magnus