Necessary with input capacitors on EQ? - diyAudio
Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

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 30th December 2013, 09:10 PM   #1
diyAudio Member
 
hansibull's Avatar
 
Join Date: Jan 2013
Location: Oslo
Default Necessary with input capacitors on EQ?

Hi!
I just got THIS NE5532 based EQ form Ebay today, and I immediately sat down and started soldering.

I discovered this kit had a pair of cheap 4.7uF input capacitors, but my amplifier already have a 1.0uF cap. is it necessary to have input caps on the EQ too?

Last edited by hansibull; 30th December 2013 at 09:12 PM. Reason: Bad link
  Reply With Quote
Old 31st December 2013, 03:27 AM   #2
diyAudio Member
 
indianajo's Avatar
 
Join Date: Jan 2010
Location: Jeffersonville, Indiana USA
Random sound sources put out a little DC voltage which can bang op amp outputs into the power supply rail if there is any gain at all. I've had trouble with tantalum input caps (popcorn noise from the store, 92% failure rate) and aluminum electrolytic caps are generally unreliable after 15-20 years, 5 for the really cheap ones. If you have room use a plastic film cap. If you don't have room I have been using 4.7 uf CPO ceramic caps with a 50 V rating. Yeah, they are non-linear, but the excess voltage rating straightens out the curve some; I really like them better than the tantalums with the popcorn noise. They are right next to the speaker in a power amp so I don't think the Aerovox gold ceramic caps I bought (which at >$5 each are not "cheap" caps) are not microphonic. If you are willing to put up with non-function of the EQ when the source device is at fault, you can remove them.
__________________
Dynakit ST70, ST120, PAS2,Hammond H182(2 ea),H112,A100,10-82TC,Peavey CS800S,1.3K, SP2-XT's, T-300 HF Proj's, Steinway console, Herald RA88a mixer, Wurlitzer 4500, 4300

Last edited by indianajo; 31st December 2013 at 03:30 AM.
  Reply With Quote
Old 31st December 2013, 10:08 AM   #3
diyAudio Member
 
hansibull's Avatar
 
Join Date: Jan 2013
Location: Oslo
I have a pair of expensive 3.3uF caps, but the problem is that these have very short leads, and is twice as big as the mounting holes on the PCB.
(same size and value as THESE)
I may try to fit in these, so I don't need to replace them after some time
  Reply With Quote
Old 31st December 2013, 12:05 PM   #4
diyAudio Member
 
hansibull's Avatar
 
Join Date: Jan 2013
Location: Oslo
Do you have any recommendation for input capacitors for OP-amps?
How does electrolytic caps affect the sound versus mylar caps?
  Reply With Quote
Old 3rd January 2014, 12:30 AM   #5
diyAudio Member
 
Refugee1's Avatar
 
Join Date: Jul 2012
Location: Worksop
If you connect a magnetic cartridge to the input any biasing currant for the OP amp will be grounded through the low impedance coils in the pickup.
  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
Subwoofer input+filter+eq circuit zeus_threat Subwoofers 13 6th January 2013 08:13 PM
How come signal input capacitors are not on every amp? mbeards Tubes / Valves 11 25th July 2012 04:31 PM
eq input and output buffer emosms Instruments and Amps 3 8th July 2012 02:02 AM
marantz input capacitors Marcelinho Solid State 4 10th December 2008 04:23 PM
5R4WGY/A/B , input filter capacitors riccardo Tubes / Valves 12 26th July 2005 09:08 PM


New To Site? Need Help?

All times are GMT. The time now is 10:46 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