Hey Inge
Maybe you need one of these. That would clear the neighbors out pretty
quick!
http://www.servodrive.com/basstech7.html
>>> Hfjord 09/20/07 01:23PM >>>
Wife: on one condition: your wuffer or what you call it, must not look
like
an ugly loadspeaker!
Me: promis, sweetheart.
Sending pics to Steve for audiofil section of the wall.
Inge
-----Ursprungligt meddelande-----
Från: TechNet [mailto:[log in to unmask]] För Hfjord
Skickat: den 20 september 2007 17:51
Till: [log in to unmask]
Ämne: [TN] SV: [TN] NTC:subwoofer
Thanks Guy,
According to your information:
RIAA curve @ 20 Hz is 7,500 us
My power supply Ri= 0.1 Ohm
Backup caps on supply rails is 100,000 F
Tau = R (Ohm) x C (F) > 0.1 x 0.1 = 0.01 s which is 10,000 us
Not too bad! Near RIAA spec. Fine! I'm satisfied.
Thanks again. Didn't realize it was that easy.
/Inge
-----Ursprungligt meddelande-----
Från: Guy Ramsey [mailto:[log in to unmask]]
Skickat: den 20 september 2007 17:00
Till: 'Hfjord'
Ämne: RE: [TN] NTC:subwoofer
On the output? You mean on the power supply rails?
You can calculate how long it will take to discharge the caps if you
know
the output impedance of the amp and the speaker load. These act in
series.
With the RC time constant.
http://en.wikipedia.org/wiki/RC_time_constant
Compare the output impedance of the power supply to the audio amp. How
long
it will take to charge the caps.
Then you need to decide what kind of sonic compromise you can tolerate
base
on the expected duty cycle imposed on the system by the music or sound
track
content.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Hfjord
Sent: Wednesday, September 19, 2007 4:57 PM
To: [log in to unmask]
Subject: [TN] NTC:subwoofer
Audio techies,
I've built a subwoofer with a 15" 400 Watt loadspeaker (4 Ohms). Bought
a
200 Watt low frequency 12 V amplifier. For that one, I built a 12 VDC
power
supply with 15 A toroid, regulator, OP amplifier and a backup
consisting of
totally 100,000 uF on the output. What is your experience? Will these
caps
be enough to take the short power tops in Space War or the enormous
sound
effects in Matrix or Jurassic Park? Any thumb rules or maths?
/Inge
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the
BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet
NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send
e-mail to [log in to unmask]: SET Technet Digest Search the archives of
previous posts at: http://listserv.ipc.org/archives Please visit IPC
web
site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text
in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask]
or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text
in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
