Amp Camp Amp - ACA - Page 65 - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

Pass Labs This forum is dedicated to Pass Labs discussion.

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 5th December 2012, 02:18 PM   #641
bcmbob is offline bcmbob  United States
diyAudio Member
 
Join Date: Dec 2009
Location: Bay City, Michigan
Quote:
Originally Posted by fastbike1 View Post
I do find no small irony that Nelson designed this amp to be a great performing, SIMPLE design, delivered same and yet folks just can't resist "messing" with the amp.

Seems to me that if you want more you ought to be building an F5 Turbo.
I resemble that remark

My query about the PC power supply was prompted more by a desire to save a few pennies by using what's on hand - if possible. Also have a chassis design that would aesthetically benefit from not using a brick. The only way I know how to get an answer is to ask a question. I would suspect any designer would allow some tweaking. If not - we wouldn't see version numbers on PCBs.

In my case, the ACA is an introduction to something other than LM3886 based amps. It's a journey I've been contemplating for about three years. With that in mind, I have ordered and am expecting delivery on a F5 design based kit as a next step. Had a couple nice phone conversations with the folks at PassDiy and 6L6 about where to go after that - if necessary.

So I'm looking forward to this new adventure and am already thrilled at the quick and informative responses found in the "House Heater" community.

P.S. I do have two 18.5V laptop bricks I will use for the initial build. Plus - the Peter Daniels PCBs are on the way. If not here, they will be put to good use with other projects.
__________________
Bob M.
"Arrange Whatever Pieces Come Your Way."

Last edited by bcmbob; 5th December 2012 at 02:28 PM.
  Reply With Quote
Old 5th December 2012, 06:30 PM   #642
bcmbob is offline bcmbob  United States
diyAudio Member
 
Join Date: Dec 2009
Location: Bay City, Michigan
OOps! I didn't order any mica pads as I'm used to the insulated LM3886TF chips. I do have a supply of thermal insulating tape left over from some computer projects. Will that be sufficient? It's 10 mils - maybe two layers?

BTW: Has anyone pointed a laser thermometer at the ACA when in full operation?
__________________
Bob M.
"Arrange Whatever Pieces Come Your Way."

Last edited by bcmbob; 5th December 2012 at 06:46 PM.
  Reply With Quote
Old 6th December 2012, 05:20 PM   #643
diyAudio Member
 
Join Date: Oct 2004
Quote:
Originally Posted by bcmbob View Post
BTW: Has anyone pointed a laser thermometer at the ACA when in full operation?
Using an 8x3" heatsink similar to the one in the diy store, I found that it runs pretty hot. It was 48 deg C on the chip and around 35 deg on the sink after about a couple of hours. Wonder what it will be like in the summer. I would suggest using a bigger sink for this.
__________________
-uv-
  Reply With Quote
Old 8th December 2012, 06:17 AM   #644
Variac is offline Variac  United States
diyAudio Editor
 
Variac's Avatar
 
Join Date: Dec 2001
Location: San Francisco, USA
I think it's just great t hat people mess with this amp. They might learn some stuff. My only concern would be that people might assume that it NEEDS to be modified, and that's not true at all. Just build it stock and you'll be amazed. Mess with it and you'll have some fun and it might sound even better to you..
  Reply With Quote
Old 8th December 2012, 01:20 PM   #645
billyk is offline billyk  United States
diyAudio Member
 
billyk's Avatar
 
Join Date: Oct 2005
Location: North Central Mass, USA
Quote:
Originally Posted by Variac View Post
I think it's just great t hat people mess with this amp. They might learn some stuff. My only concern would be that people might assume that it NEEDS to be modified, and that's not true at all. Just build it stock and you'll be amazed. Mess with it and you'll have some fun and it might sound even better to you..
Oh yes, exactly! Stock just as it comes is really wonderful.
As soon as I finish putting it together I will get some more parts and start to play with it. There lots of good ideas in this thread. Plus I will have something to listen to while I experiment!
  Reply With Quote
Old 8th December 2012, 05:22 PM   #646
diyAudio Member
 
bnorrish's Avatar
 
Join Date: Oct 2012
Location: Boston
I do not think it needs to be modified in terms of sound. I am very impressed. Not really pretty sitting in my office. I thought up putting it in a nice chassis, PSU board and transformer, etc. Started adding up the costs and thought it would be better to invest in an F5 build. This amp did stoke my obsessive compulsive behavior and it got me hooked on a new hobby! The UPS man keeps coming and wife keeps asking "How much is this all going to cost?"

Last edited by bnorrish; 8th December 2012 at 05:25 PM.
  Reply With Quote
Old 9th December 2012, 05:10 AM   #647
diyAudio Member
 
Join Date: May 2001
Location: Bangalore, India
It might help every enthusiast here if someone could give a detailed comparative sonic report between ACA and F5.
__________________
Sam
  Reply With Quote
Old 9th December 2012, 07:17 PM   #648
bcmbob is offline bcmbob  United States
diyAudio Member
 
Join Date: Dec 2009
Location: Bay City, Michigan
Shucks. I ordered 0.68 ohms @ 2 watts instead of 3 watts for R3-4. Can I use them till I get the proper pieces.

Don't like green smoke !!
__________________
Bob M.
"Arrange Whatever Pieces Come Your Way."
  Reply With Quote
Old 10th December 2012, 01:09 AM   #649
diyAudio Member
 
Join Date: Oct 2004
Quote:
Originally Posted by Samuel Jayaraj View Post
It might help every enthusiast here if someone could give a detailed comparative sonic report between ACA and F5.
Initial impressions after a week or so of playing it through a full range speaker(Alpair 7.3 in a BIB). The sound is closer to my Aleph 3 than the F5. Warmer, better mid-range etc. But ultimately it did not measure up to my SET2A3 into the same speaker. The SET actually had better extension -both upper and lower- than this amp which was surprising.
But it is a great little amp and dead quiet. It is going to be the center piece of a smaller system that I plan to put together for near field listening. And off course I have to try a non-smps to see what that sounds like.

I think that is one of he charming things about this amp. I slapped it together in a couple of hours once I had the boards from parts I had lying around including heat sinks and laptop power supplies. It is a nice little diversion from the all the other bigger projects that await me in various stages of incompletion - speakers, amps, dacs, cd players, turntables and I don't know what else. So many things to build, so little time!!!
__________________
-uv-
  Reply With Quote
Old 10th December 2012, 04:53 AM   #650
diyAudio Member
 
Loudthud's Avatar
 
Join Date: Nov 2007
Location: Near Dallas Texas USA
Quote:
Originally Posted by bcmbob View Post
Shucks. I ordered 0.68 ohms @ 2 watts instead of 3 watts for R3-4. Can I use them till I get the proper pieces.

Don't like green smoke !!
They should work fine.
  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
Amp Camp Amp #1 Nelson Pass diyAudio.com Articles 35 12th September 2014 02:49 AM
Amp Camp! Jason Site Announcements 2 30th June 2012 03:57 PM
Best D camp config for Tweeter amp Zero One Class D 0 24th February 2010 05:57 AM
better the Pass camp? rick57 Tubes / Valves 6 26th March 2005 07:04 AM


New To Site? Need Help?

All times are GMT. The time now is 12:37 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