Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

The Lounge A place to talk about almost anything but politics and religion.

John Curl's Blowtorch preamplifier part II
John Curl's Blowtorch preamplifier part II
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Closed Thread
 
Thread Tools Search this Thread
Old 4th January 2013, 05:22 AM   #32201
qusp is offline qusp  Australia
diyAudio Member
 
qusp's Avatar
 
Join Date: Oct 2009
Location: Brisbane, Australia
depends on the batteries. I have several battery packs with impedance less than 12.5mOhms and capable of 140A
 
Old 4th January 2013, 05:45 AM   #32202
RNMarsh is offline RNMarsh  United States
diyAudio Member
 
RNMarsh's Avatar
 
Join Date: May 2012
Location: 2457 Cascade Trail; Cool, CA. 95614
John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by qusp View Post
depends on the batteries. I have several battery packs with impedance less than 12.5mOhms and capable of 140A
They all start out fine but dont end up that way in use over time.
 
Old 4th January 2013, 06:51 AM   #32203
Esperado is offline Esperado  France
Banned
 
Join Date: Jul 2011
Location: Portugal
Quote:
Originally Posted by RNMarsh View Post
They all start out fine but dont end up that way in use over time.
What kind of batteries are-you refering-to ? Acid, cadmium or lithium/ion ? (I'm more thinking to a preamplifier than a power amp, of course)
 
Old 4th January 2013, 07:19 AM   #32204
qusp is offline qusp  Australia
diyAudio Member
 
qusp's Avatar
 
Join Date: Oct 2009
Location: Brisbane, Australia
Quote:
Originally Posted by RNMarsh View Post
They all start out fine but dont end up that way in use over time.
yeah look i'm not sure you have used anything like what i'm talking about. with proper care in undervoltage protection and the use of chargers designed for them, quality LiFePO4 last for literally thousands of full cycles at much higher discharge rates than what we are speaking of here. i've been using the ones I have here daily for well over 18months and they still perform pretty much as the day I bought them. they are 2300mah. there are also higher capacity ones if need be, but for a preamp I could see them not needing charging for a week (24hrs of use at 100mA for example) so 1000 weeks is ~20years and they should still be sitting at roughly 90% capacity of new

Last edited by qusp; 4th January 2013 at 07:22 AM.
 
Old 4th January 2013, 11:05 AM   #32205
gpapag is online now gpapag  Greece
diyAudio Moderator
 
gpapag's Avatar
 
Join Date: Nov 2002
Location: Athens-Greece
John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by SY View Post
Don't forget Kelvin caps!
SY
What kind of animal is this ? (I searched but didn't find any explanation)

George
__________________
["Second Law is a bitch." - SY]
["I insist on respecting the means of the average person working in their garage/basement." -Scott Wurcer]
 
Old 4th January 2013, 11:31 AM   #32206
Esperado is offline Esperado  France
Banned
 
Join Date: Jul 2011
Location: Portugal
Quote:
Originally Posted by gpapag View Post
SY
What kind of animal is this ? (I searched but didn't find any explanation)
What ? You don't know ?
(i asked myself the same question)
 
Old 4th January 2013, 11:40 AM   #32207
qusp is offline qusp  Australia
diyAudio Member
 
qusp's Avatar
 
Join Date: Oct 2009
Location: Brisbane, Australia
4 leaded caps I presume, with kelvin connection
 
Old 4th January 2013, 11:41 AM   #32208
cliffforrest is offline cliffforrest  United Kingdom
diyAudio Member
 
Join Date: Sep 2004
Location: South Coast, UK
John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by gpapag View Post
SY
What kind of animal is this ? (I searched but didn't find any explanation)

George
Probably these:
http://www.nist.gov/calibrations/upload/tn1024.pdf

4 terminal = Kelvin connections.
 
Old 4th January 2013, 11:51 AM   #32209
john curl is offline john curl  United States
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
Kelvin caps, I used them once, long ago.
However, Richard is correct. We both know from EXPERIENCE what a pain in the --- that batteries can be. We have both designed with batteries, they 'float' but give little more than that compared to a 1'st Class AC-DC power supply.
__________________
"Condemnation without Examination is Prejudice"
 
Old 4th January 2013, 12:46 PM   #32210
SY is offline SY  United States
On Hiatus
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by qusp View Post
4 leaded caps I presume, with kelvin connection
Exactly. Suppression Devices sells them at pretty reasonable cost. The advantages in power supplies are small but measurable.
__________________
"You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is."
 

Closed Thread


John Curl's Blowtorch preamplifier part IIHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


New To Site? Need Help?

All times are GMT. The time now is 04:49 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki