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 24th July 2003, 03:40 PM   #21
diyAudio Member
 
Join Date: Mar 2003
Location: Austin
Send a message via AIM to ScottRHinson
Quote:
Originally posted by Peter Daniel



You are not saying that because of my suggestion to place it in a center?

My reasoning to put it centrally is following. This is quite a big chassis by GC standards. If this is stereo amp, you should definitely use dual mono layout, with ea channel on either side and probably using side panels for heatsinking. This leaves the center space empty and it's a perfect place to mount transformer, or maybe even two. Also AC input should be placed centrally and both RCA jacks and binding posts separate on both ends of rear panel. Placing transformer centrally makes for better balanced chassis as well, not to mention having the same resonances for both channels
I'm sorry Peter, but I disagree. The cheapest way to reduce noise in an electrical system is distance...pure and simple. The best way is a well thought out grounding system and Faraday cages around the noisy and quiet parts to separate them.

I assume EMI is what you mean by the term resonance?

I have never liked a dual mono layout because it becomes much easier to make a mistake in running signals near power lines, either the full wave primary or rectified secondary lines. Those secondary currents can get all over the place if your not careful and easily set the noise and distortion floor for the amplifer.

Can it be done well? Yes. Is it much harder. Yup. If I were the builder of this amp, I'd get a big piece of aluminum bar stock and wedge it into one side of the amp. If it were the right size it could tie the side to the top and bottom thermally and even the front and back. I'd mount the gainclone chips to that, and you have a huge thermal mass to cool the chips. You can keep the chips as far away from those nasty power supply lines and realize the lowest noise floor, quietest amp you can.

Scott
  Reply With Quote
Old 24th July 2003, 04:00 PM   #22
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
This will work too. I guess it's a matter of preference. With a big chassis like that you can use almost any layout. I just like symmetry and separation between channels.
__________________
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 24th July 2003, 04:01 PM   #23
Bricolo is offline Bricolo  France
diyAudio Member
 
Bricolo's Avatar
 
Join Date: Nov 2002
Location: Grenoble, FR
The 1st solution has the transformer on the side

advantages:
less EMI from the transformer

disadvantages:
I can't use a long axis for the volume pot


the 2nd has the transformer on the middle:
advantages:
I can use a long axis

disadvantage:
EMI




In both cases, I can place metal plates around the transformer
but it I do this, in the 2nd case, the AC inlet wires aren't in this small housing
Attached Images
File Type: gif 2.gif (6.3 KB, 542 views)
  Reply With Quote
Old 24th July 2003, 04:04 PM   #24
Bricolo is offline Bricolo  France
diyAudio Member
 
Bricolo's Avatar
 
Join Date: Nov 2002
Location: Grenoble, FR
2nd one:


note that with the 2nd option, I can use both sides as a heatsinks (maybe this isn't critical with a gainclone)
Attached Images
File Type: gif 1.gif (6.0 KB, 536 views)
  Reply With Quote
Old 24th July 2003, 04:20 PM   #25
diyAudio Member
 
Join Date: Mar 2003
Location: Austin
Send a message via AIM to ScottRHinson
Quote:
Originally posted by Bricolo
The 1st solution has the transformer on the side

advantages:
less EMI from the transformer

disadvantages:
I can't use a long axis for the volume pot


the 2nd has the transformer on the middle:
advantages:
I can use a long axis

disadvantage:
EMI




In both cases, I can place metal plates around the transformer
but it I do this, in the 2nd case, the AC inlet wires aren't in this small housing



I see that you've got dual potentiometers for volume control. I'm going to modify/clarify some of my advice. Bring the power wiring straight forward from the transformer on the right side. Run it side to side along the very front of the chassis, then back to the GC amps on the left side along the left side.

Now take the speaker output straight back and exit the far corner (this is different than I said before, now that I see the layout this makes more sense). Bring the signal lines in next to the speaker out and keep them as short as possible. I'm guessing you want to have a symmetrical front panel? If you're not attached to it, put both pots on the left 1/3 of the chassis, it will still look pretty classy and you'll be able to keep the signal wiring perpendicular, or orthagonal (spelling?) to the power lines as much as you can. Make sense?

Scott
  Reply With Quote
Old 24th July 2003, 04:22 PM   #26
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Here's a nice example of what I was talking about: http://www.hifis.com/brink/brink.htm
__________________
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 24th July 2003, 04:26 PM   #27
Bricolo is offline Bricolo  France
diyAudio Member
 
Bricolo's Avatar
 
Join Date: Nov 2002
Location: Grenoble, FR
Quote:
Originally posted by ScottRHinson





I see that you've got dual potentiometers for volume control. I'm going to modify/clarify some of my advice. Bring the power wiring straight forward from the transformer on the right side. Run it side to side along the very front of the chassis, then back to the GC amps on the left side along the left side.

Now take the speaker output straight back and exit the far corner (this is different than I said before, now that I see the layout this makes more sense). Bring the signal lines in next to the speaker out and keep them as short as possible. I'm guessing you want to have a symmetrical front panel? If you're not attached to it, put both pots on the left 1/3 of the chassis, it will still look pretty classy and you'll be able to keep the signal wiring perpendicular, or orthagonal (spelling?) to the power lines as much as you can. Make sense?

Scott
Yes, I want a symmetrical front pannel
  Reply With Quote
Old 24th July 2003, 04:29 PM   #28
Bricolo is offline Bricolo  France
diyAudio Member
 
Bricolo's Avatar
 
Join Date: Nov 2002
Location: Grenoble, FR
Quote:
Originally posted by Peter Daniel
Here's a nice example of what I was talking about: http://www.hifis.com/brink/brink.htm

That's the layout I was also thinking about

But where is the AC inlet?
  Reply With Quote
Old 24th July 2003, 04:32 PM   #29
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 Bricolo


But where is the AC inlet?

It is probably coming through the bottom, directly to the transformer.
__________________
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 24th July 2003, 04:35 PM   #30
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
I wouldn't recommend dual volume pots as it's very inconvenient to adjust volume. Why not a single pot?
__________________
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

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
unfinished gainclone merlin2069er Swap Meet 0 8th December 2008 05:42 PM
F3 unfinished project for sale hc167 Swap Meet 5 27th September 2008 07:36 AM
Gaincline Bi-Amp / Active Crossover - work in progress gainphile Chip Amps 10 5th January 2008 11:35 PM
fs: unfinished gainclone MERLIN2049ER Swap Meet 10 19th February 2006 01:49 AM
Phodies of my unfinished projects. Bas Horneman Everything Else 4 30th January 2004 07:20 AM


New To Site? Need Help?

All times are GMT. The time now is 08:30 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