"The Wire" Ultra-High Performance Headphone Amplifier - PCB's - Page 174 - diyAudio
Go Back   Home > Forums > Amplifiers > Headphone Systems

Headphone Systems Everything to do with Headphones

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
Reply
 
Thread Tools Search this Thread
Old 8th January 2013, 04:14 AM   #1731
opc is offline opc  Canada
diyAudio Member
 
opc's Avatar
 
Join Date: Oct 2004
Location: Ottawa, Ontario, Canada
Quote:
Originally Posted by merlin2069er View Post
I'm almost finished with "the wire" headphone amp. I just have to wire up the jack and power switch.

I have a led rocker switch, that I might swap out. It requires 12vdc to power up the led when it's switched on (I believe). I guess I can't wire it directly to the incoming ac.

What are the trim pots on amp for again? I'm certain I've already set them and forgot about them.
Much of the above is a little scary, but let's see what we can do:

1. No, 120VAC across an LED is probably not a good idea. If you have a spec sheet you can check how they implemented the LED in the switch. If it needs 12V, you can probably wire a resistor in series and power it off the +12-15V rail from the PSU. It's best to err on the side of caution.

2. The trimpots are on the PSU and they set the rail voltage for the +/- rails that supply the amp. You want to adjust them to get the +/- voltage you decide to run. In your case, if you don't need extra high output voltage swing, I would simply set it at +/-12V and be done. That way you can power your LED directly

Cheers,
Owen
  Reply With Quote
Old 8th January 2013, 04:24 AM   #1732
diyAudio Member
 
Join Date: Feb 2009
Location: Brisbane, Australia
I was going to come back and edit my post, don't need to now

I would like to add one thing though, please, when you're building anything electrical, look at the schematic and the datasheets while you build it and then double (or tripple check) your wiring before hooking anything up to power.

Chris
  Reply With Quote
Old 8th January 2013, 01:59 PM   #1733
nattawa is online now nattawa  Canada
diyAudio Member
 
Join Date: Apr 2010
Location: Mississauga, Ontario
Quote:
Originally Posted by merlin2069er View Post
I'm almost finished with "the wire" headphone amp. I just have to wire up the jack and power switch.

I have a led rocker switch, that I might swap out. It requires 12vdc to power up the led when it's switched on (I believe). I guess I can't wire it directly to the incoming ac.

What are the trim pots on amp for again? I'm certain I've already set them and forgot about them.
I'm quite sure you had your PSU set at +/-15V by the trim pots

Never wire the incoming AC to the LED unless your rocker switch is rated for live potential for the LED part and you know how to wire live circuit to the safety codes.

Owen's idea about the LED wiring is good. Just wire it to one of the rails with a resistor of 4k7 in series. LEDs are diodes that will pass a current one way. If it doesn't light up reverse the polarity. Experiment with the resistor value for a desired brightness. I had my front panel LED powered across the rails at 30V with a 27K resistor in series. There is only about 1mA current and the LED gives a quiet, subtle glow, yet still stands out the mess on my desk.
  Reply With Quote
Old 8th January 2013, 03:19 PM   #1734
diyAudio Member
 
merlin2069er's Avatar
 
Join Date: Sep 2008
Location: Toronto
Blog Entries: 1
Send a message via MSN to merlin2069er
Thanks! Right the the trim pots are for the PSU.

Ok, I guess I can use a power switch (with led) rated for AC power?
  Reply With Quote
Old 8th January 2013, 03:26 PM   #1735
qusp is offline qusp  Australia
diyAudio Member
 
qusp's Avatar
 
Join Date: Oct 2009
Location: Brisbane, Australia
I dont think you will find a switch with LED rated for AC, it would need to have separate power for the LED, or some crazy step down from mains to 5-10vdc, aint gonna happen. most LED switches are momentaries

that and LED dont work with AC ever, they need DC voltage

actually DC current. I guess the LED replacement light bulbs that are becoming more widespread have some sort of rectifier in them and maybe a zener? maybe i'm wrong, I have just never heard of an LED that takes AC anything voltage or current

Last edited by qusp; 8th January 2013 at 03:32 PM.
  Reply With Quote
Old 8th January 2013, 03:29 PM   #1736
opc is offline opc  Canada
diyAudio Member
 
opc's Avatar
 
Join Date: Oct 2004
Location: Ottawa, Ontario, Canada
How about posting a part number or datasheet... then maybe we can help.

It might not even be an LED in there for all we know.

Cheers,
Owen
  Reply With Quote
Old 8th January 2013, 03:35 PM   #1737
qusp is offline qusp  Australia
diyAudio Member
 
qusp's Avatar
 
Join Date: Oct 2009
Location: Brisbane, Australia
x2^^


Quote:
Originally Posted by opc View Post
How about posting a part number or datasheet... then maybe we can help.

It might not even be an LED in there for all we know.

Cheers,
Owen
I think its more likely it has an LED and hes seen them used for mains...as momentaries controlling relays. lots of PC tuning websites and ebay shops sell them. they take 12vdc normally and do NOT like mains AC across them

but yes pic + datasheet or part # or we cant really help.

Last edited by qusp; 8th January 2013 at 03:40 PM.
  Reply With Quote
Old 8th January 2013, 05:35 PM   #1738
IanAS is offline IanAS  England
diyAudio Member
 
Join Date: Dec 2004
Location: London
Could be a Neon lamp in the mains switch.
  Reply With Quote
Old 8th January 2013, 05:49 PM   #1739
diyAudio Member
 
merlin2069er's Avatar
 
Join Date: Sep 2008
Location: Toronto
Blog Entries: 1
Send a message via MSN to merlin2069er
Ok, I'll pop it out of the front panel and take a look at it.

It came with a chassis, I'll have to look it up somehow.
  Reply With Quote
Old 8th January 2013, 06:54 PM   #1740
qusp is offline qusp  Australia
diyAudio Member
 
qusp's Avatar
 
Join Date: Oct 2009
Location: Brisbane, Australia
nah if it came with it, it'll be a momentary with LED, especially on the front, not many people, let alone companies would design it so you had to take mains to the front panel from the rear to the switch and back again. seems unlikely anyway.
  Reply With Quote

Reply


Hide 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Which Pass Aleph diy board for "no-cost-object" headphone amplifier? Hammerklavier Headphone Systems 43 7th August 2010 03:35 PM
Improvments to "Tube Headphone Amplifier/Preamp with Relay-Based Input and Power Swi" kipman725 Headphone Systems 4 17th August 2009 06:12 PM
Project 11.1 from Slone "High-Power Amplifier" Book Karl71 Solid State 46 6th October 2008 03:47 AM
The "Freebird" ultra clean ultra simple preamp design Russ White Chip Amps 87 11th August 2008 09:28 AM
My A.N.T. "Amber" headphone amplifier x-pro Headphone Systems 8 1st October 2007 08:47 AM


New To Site? Need Help?

All times are GMT. The time now is 02:39 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2