Re: kern/51784: "Synthesized" speaker hums

[Paul Goyette <paul%whooppee.com@localhost>]

The following reply was made to PR kern/51784; it has been noted by GNATS.

From: Paul Goyette <paul%whooppee.com@localhost>
To: Nathanial Sloss <nat%netbsd.org@localhost>
Cc: gnats-bugs%netbsd.org@localhost
Subject: Re: kern/51784: "Synthesized" speaker hums
Date: Wed, 24 May 2017 11:13:29 +0800 (+08)

 On Wed, 24 May 2017, Nathanial Sloss wrote:
 
 > Hi,
 >
 > I've just finished a better implemetation of audiobell that should have little
 > to no hum.  The probelm with the existing audiobell.c is that the maximum bell
 > pitch is just 4 kHz with the patch it would be 22 kHz.
 >
 > The resolution of the data used to generate the sine wave has been increased
 > from 65 bytes to 2049 bytes, as the original 65 byte version genetated a
 > rather square-ish sinewave at some frequencies and the hum would be a
 > harminic.
 >
 > The hires version generates a better looking sine wave.
 >
 > To use apply this patch:
 > ftp.netbsd.org/pub/NetBSD/misc/nat/hiresbell.diff
 > and add the following to your kernel config:
 > options HIRES_BELL
 >
 > Please let me know if this resolves the "hum".
 
 Sorry, it does _not_ resolve the "hum" problem.
 
 
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