Need help designing crossover - Page 3 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

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
Reply
 
Thread Tools Search this Thread
Old 27th November 2003, 02:43 PM   #21
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
Well, now I am waiting for the chips to get here. But until then, does the 837 and the 324 have the same pinouts and run off of a single supply, so I could use the 324 until the 837 arrives?

Thanks, Mike
  Reply With Quote
Old 28th November 2003, 12:21 AM   #22
diyAudio Member
 
Join Date: Dec 2001
Location: SIUE, Illinois, USA
i'm betting yes. check www.national.com lm324 and lm837
__________________
if only it could be used for good, not evil...
  Reply With Quote
Old 28th November 2003, 12:20 PM   #23
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
Looks like this is a split supply chip. I don't see a ground pin, though. It does have a VEE and VCC connections and says the max voltage is +-18V. If it is split, where is the gnd connection?
  Reply With Quote
Old 29th November 2003, 04:42 AM   #24
diyAudio Member
 
Join Date: Dec 2001
Location: SIUE, Illinois, USA
that's the beauty of opamps, there is no ground pin.

basically ground is just a "referance". an opamp tries to do one thing: make the input terminal become equal in voltage by use of a feedback path.

as you can see, ground isn't mentioned, and doens't need to be attached to the chip. notice that all opamp circuits will have resistors attached to ground and to an input. this is a way of referanceing the signal to ground. so long as the output stays between +18V and -18V it is fine, and you could build the circuit so Vcc/2 was concidered ground.
__________________
if only it could be used for good, not evil...
  Reply With Quote
Old 29th November 2003, 11:19 AM   #25
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
So I could just run it off of a single supply bv connecting + to VCC and gnd to VEE? And power it off of something like a 7805 (if that has enough voltage)? I do have some 7905 also, if it does need split.
  Reply With Quote
Old 1st December 2003, 01:39 AM   #26
diyAudio Member
 
Join Date: Dec 2001
Location: SIUE, Illinois, USA
well, if you run from single supply you need to add a DC offset to the input signal, then remove it from the output signal.

basically, the opamp will try to output a signal that would make both input terminals be at equal voltage. now for an AC input, that means there are times when the opamp needs to put out a negative voltage, and times when it needs a positive voltage. if you run from a single supply, the opamp will not be able to put out negative voltages, as the power supply will not allow it. so if you add a little bit of DC to the AC signal, you will get a signal that you can work with, but also you will need to remove the DC offset. this means capacitors in the signal path. most audiophiles attempt to minimize the number of capacitors and especially the number that could most affect the signal.

i would use a split supply if possible. if you must do single supply: http://instruct1.cit.cornell.edu/cou...ngleSupply.pdf
__________________
if only it could be used for good, not evil...
  Reply With Quote
Old 1st December 2003, 02:04 AM   #27
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
Thanks. The only reason I asked was because I know the LM324 is a single supply chip, and the 837 is a split supply. I didn't think it was possible to interchange them.

I can wait a couple of days for the samples to arrive.
  Reply With Quote
Old 7th December 2003, 02:08 AM   #28
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
OK, I finally got the chips yesterday. Now, what would be a good circuit to use? Should I use the lowpass crossover in winisd pro? Or something else? Also, what order does it need to be?
  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
Please help with the designing of a passive crossover network! Big_Bill Multi-Way 74 17th July 2009 04:53 AM
Designing a crossover oldbar Multi-Way 2 2nd February 2009 11:48 PM
Help for Crossover Designing for 3 way speaker CH2 Multi-Way 16 9th April 2004 04:01 PM
designing crossover fr Thiel and Eton... woofes Multi-Way 16 20th February 2004 03:58 AM
noob needs help designing crossover helpmeplease Multi-Way 3 21st December 2003 11:22 PM


New To Site? Need Help?

All times are GMT. The time now is 10:05 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