LM4780 Questions - Page 2 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Chip Amps Amplifiers based on integrated circuits

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
Thread Tools Search this Thread
Old 31st August 2012, 08:20 PM   #11
Marra is offline Marra  United Kingdom
diyAudio Member
Join Date: Nov 2009
Location: Near Lincoln
These are a nice switch for two inputs.

5646A9 - APEM - SWITCH, DPDT | Farnell United Kingdom
  Reply With Quote
Old 1st September 2012, 08:52 PM   #12
Einric is offline Einric  United States
diyAudio Member
Einric's Avatar
Join Date: Feb 2011
Location: Bozeman, MT
Digikey also carries DP3T switches if you want another input.
  Reply With Quote
Old 2nd September 2012, 04:30 PM   #13
tsiros is offline tsiros  Greece
diyAudio Member
tsiros's Avatar
Join Date: Jun 2012
Location: Patra, Greece
Send a message via MSN to tsiros Send a message via Skype™ to tsiros
Originally Posted by TP143 View Post
The stock supply caps are 2@10uf but the recommended mod is 4@6800uf, not 6.8uf. I wanted to make that correction for future scanners of this thread.

you sure they said 10uF and not 10mF?
  Reply With Quote
Old 2nd September 2012, 06:03 PM   #14
No 4 is offline No 4  United States
diyAudio Member
Join Date: Nov 2011
Location: Carterville, IL
The audiosector kit come with 10uf (microfarad) capacitors.
  Reply With Quote
Old 2nd September 2012, 08:10 PM   #15
diyAudio Member
lanchile's Avatar
Join Date: Sep 2008
Location: in my house!
Originally Posted by SoIL4x4 View Post
The audiosector kit come with 10uf (microfarad) capacitors.
yes! they come with 10uf for power supply (joke).
I am very happy with my TKD in my amp too. it is very smooth and it is a big step up from Alps for sure
  Reply With Quote
Old 2nd September 2012, 09:07 PM   #16
diyAudio Member
jackinnj's Avatar
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
If you are going to parallel the LM4780 it's a good idea to match each amplifier's Rf and Rg to 0.1%

Vee and Vcc should be bypassed with 10uF electrolytic AND 100nF ceramic.
  Reply With Quote
Old 3rd September 2012, 09:59 AM   #17
AndrewT is offline AndrewT  Scotland
diyAudio Member
Join Date: Jul 2004
Location: Scottish Borders
Cs in the datasheet are mandatory.
yes, once you have Cs fitted then you can experiment with values, but they must be fitted first.
regards Andrew T.
Sent from my desktop computer using a keyboard
  Reply With Quote
Old 3rd September 2012, 12:36 PM   #18
diyAudio Member
jackinnj's Avatar
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
And while you're at it -- if you're going to switch the mute, then a little electrolytic on the mute pin is helpful -- but make sure to note the polarity.
  Reply With Quote
Old 3rd September 2012, 07:04 PM   #19
diyAudio Member
KaffiMann's Avatar
Join Date: Sep 2009
Location: Grua, Just north of Oslo
I actually just got some SMPS from connexelectronic for my LM4780's (for bass) and LM3875's (for alpair 12), sounds very nice, ended up being cheaper than the good'ol power transformers, but I have heaps of them anyways. Put them in a MDF box I glued together for the purpose, everything is connected to the heat sink. Planning on adding an active xo and use the aux power from the SMPS for it. Just have to use my minidsp to figure out what I need first. And build the boxes for the Alpairs...
  Reply With Quote
Old 11th September 2012, 08:27 AM   #20
sangram is offline sangram  India
diyAudio Member
Join Date: Sep 2002
Location: India
The PD kit comes with 1510uF total capacitance per rail per amplifier. 1500uF on the ap board and 10uf on the PSU board. PSU board takes 10,000uF snap-in capacitors pretty easily. I have 4700uF+1500uF+10uF fitted on 4 amplifier boards (2 PD kits) in bridge-paralleled configuration and there is enough bass to pull down a wall, even with the tiny little Zaph L18 speakers.

Note the earlier caution about running multiple PS units off the same transformer. In reality it does work, But you have to absolutely match diode polarities. It caused me a lot of confusion the first time around. Each pad on the PSU board must be routed to exactly the same winding output terminal else the back-to-back diodes effectively short-circuit the winding.

Last edited by sangram; 11th September 2012 at 08:29 AM.
  Reply With Quote


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
LM4780 source questions bushroot Chip Amps 9 16th March 2008 05:38 AM
Sub' Amp - LM4780 questions! raromachine Chip Amps 23 3rd March 2007 03:20 AM
tech-diy LM4780 board questions Burnedfingers Chip Amps 1 13th January 2007 02:06 PM
bridging 2x paralleled LM4780 per channel - few questions bikehorn Chip Amps 6 28th April 2006 06:13 PM
Several Questions about the LM4780 GainClones geewhizbang Chip Amps 14 15th June 2004 08:18 PM

New To Site? Need Help?

All times are GMT. The time now is 12:59 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2