bi amping - 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 19th September 2003, 08:59 PM   #1
diyAudio Member
 
Join Date: Aug 2003
Location: Rome
Default bi amping

hello all

I have in mind to build 2 stereo gainclone, one for each channel.
My diy loudspeakers are proac 2.5 clone, with sacn-speak 18w8535 and 2905/9500.
Using 4 transformers I can tweak the voltage for each driver, using only 2 transformers no.
I can choose to use 4x160va transformers or only 2x300va, but which voltage ? 18v ? 25v ?
And which components can I tweak for the treble and which for the bass section ?
Advices are welcome !


--
felipe
  Reply With Quote
Old 20th September 2003, 12:44 AM   #2
dhenryp is offline dhenryp  United States
diyAudio Member
 
Join Date: Aug 2003
Location: Mass.
Four transformers or two may be as much a matter of religion as anything else. If there is no cost difference (or you don't care about cost) go with the four transformers. If cost matters, I would not feel bad about going with the two. I would choose 25v for the base speakers, which will give you full output (56+ watts) from an LM3886. You can get by with a lower voltage, and power for the tweeters, 20 volts is probably more than enough. I'm not sure of the power tha will give you but it's probably on the order of 35-40 watts.

You can't tweek gainclone components to get high pass and low pass crossover filters. You need an active crossover. I'm building a two way actively crossed speaker and I'm using the 24db/octave Linkwitz-Riley crossover from here:

http://sound.westhost.com/project09.htm

Read the paper on bi-amping at this site also. It will give you lot's of good information:

http://sound.westhost.com/bi-amp.htm

Good luck.
  Reply With Quote
Old 20th September 2003, 12:53 AM   #3
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Quote:
Originally posted by dhenryp


You can't tweek gainclone components to get high pass and low pass crossover filters. You need an active crossover. I'm building a two way actively crossed speaker and I'm using the 24db/octave Linkwitz-Riley crossover from here:
You shouldn't have any problem with getting 1st or 2nd high pass and low pass filters with tweaking GC components. I don't know about 24db/octave filters, but usually it's not required and doesn't sound as good as simple filters.
__________________
www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC
  Reply With Quote
Old 20th September 2003, 08:49 PM   #4
JoeBob is offline JoeBob  Canada
diyAudio Member
 
JoeBob's Avatar
 
Join Date: Nov 2001
Location: Montreal, Canada
You could set up a passive line level xover before the gainclone, then 1st or 2nd is very simple to achieve, I think this is what Peter was refering to. Planet10 (Dave) has a simple article about this on his webpage, you should check it out.

It would be perfect because you could adjust the gain to make up for the losses and if you make the xover built into the amp the impedances wouldn't ever change.
  Reply With Quote
Old 20th September 2003, 10:59 PM   #5
diyAudio Member
 
Join Date: Aug 2003
Location: Rome
Thanks for the answers, I learned a lot

I like wery much the simple solution that Peter pointed out.

JoeBob, I cant find the document you mentioned, and I need a 3th order LP/HP filter at 3khz.
Is it hard to do ?
While I learn where to begin, can someone give me little more help ?

Thanks all for now
  Reply With Quote
Old 24th September 2003, 12:09 AM   #6
diyAudio Member
 
Join Date: Aug 2003
Location: Sector ZZ9 plural Z alpha
Low/high pass filters can be added right into the feedback loop. Make them toggleable, or adjustable in some way.
  Reply With Quote
Old 24th September 2003, 02:05 AM   #7
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Implementing filter functions in chip amps may be problematic- the amp has to be unity gain stable. There are no doubt some compensation tricks that could be done, but it would be easier and more certain to do the filter functions separately with a more conventional op-amp.
__________________
You might be screaming "No, no, no" and all they hear is "Who wants cake?" Let me tell you something: They all do. They all want cake.- Wilford Brimley
  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
Bi-amping diyman Multi-Way 14 31st August 2012 12:24 AM
Bi amping adventfan Solid State 14 26th June 2008 03:28 PM
Bi-Amping.....Which one where? THUMP LUMP Solid State 3 17th December 2007 08:24 PM
Bi-amping keyser Multi-Way 2 10th February 2005 11:57 AM
Tri amping SOZ Magura Pass Labs 6 8th January 2004 08:51 PM


New To Site? Need Help?

All times are GMT. The time now is 01:57 PM.


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