F5 Turbo Circuit Boards - Page 82 - 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 29th February 2012, 04:27 PM   #811
lhquam is offline lhquam  United States
diyAudio Member
 
Join Date: Mar 2010
Location: Olalla, Oregon: Land of the 100 Valleys
Quote:
Originally Posted by Horio View Post
Your option 1 is very similar to what I am wanting to build (except I would be using 8 single FET output boards per channel). I've realized that I don't need to cascode as the rails on the balanced build are going to be half that of an equivalent power single-end amp. I'm thinking of shooting for +/-24V rails which should be well within the safe limit for the JFETs.
I have ideas for 3 versions of the balanced F5T:
  1. Balanced stereo at 46W/channel using 2 x 1/2 E007 heatsink with fan as shown in F5 power amplifier.
  2. Balanced stereo at 100W/channel using 2 x E007 heatsinks fin-to-fin with 2 fans.
  3. Balanced monoblock at 200W/channel using 2 x E007 heatsinks fin-to-fin with 2 fans.
  Reply With Quote
Old 29th February 2012, 05:06 PM   #812
sekess is offline sekess  United States
diyAudio Member
 
Join Date: Feb 2006
Location: NJ
Default Heatsink Sim

Hey Ihquam,
I was thinking about up a similar forced air build. Where did you get the heatsink simulation software from?
Thanks,
Steve


Quote:
Originally Posted by lhquam View Post
Here is a heatsink simulation based on using 1-1/2 HeatsinkUSA E007.
Unfortunately, HeatsinkUSA doesn't make anything wider than 256 mm, so I cut one E007 in half and weld it to a full E007 to make a 36 fin 384 wide. The resulting heatsink is 384 mm (W) x 130 mm (L) x 74 mm (H), with a baseplate thickness of 9.5 mm and has 36 fins. Too bad that such a heatsink isn't available off-the-shelf.

The simulation assumes 8 MOSFETs dissipating 22 watts each spaced according to the F5-Turbo-v2/3 layout. I also assume FORCED CONVECTION. The image shows the heat rise using .693 m/s air flow rate. Looks pretty good.

I imagine assembling two such heatsinks with the fins facing each other and using 3x 120mm low-noise fans in the same manner I used with the F5 shown HERE: F5 power amplifier
  Reply With Quote
Old 29th February 2012, 06:54 PM   #813
sippy is offline sippy  United Kingdom
diyAudio Member
 
Join Date: Jun 2008
Toecutter,
I was intending the V3 build as a long term project as the build cost is looking some what.......large.
I dont know what kinda beta testing time frame you would be looking at, but I'm willing to beta a V2 build, if you want to talk more I'll shoot you a pm with my email addy.
  Reply With Quote
Old 29th February 2012, 07:07 PM   #814
Tea-Bag is offline Tea-Bag  United States
not politcally affiliated
diyAudio Member
 
Tea-Bag's Avatar
 
Join Date: Feb 2006
Location: Kennebunk
Blog Entries: 7
Prototyping doesn't necessarily mean doing everything all nice and tidy.
If you can get the front end, and maybe a pair of outputs working on a channel with a MUR3020, I say it's good to go.
Some of it is about component stuffing to make sure things in reality put together fairly easily and precisely.
  Reply With Quote
Old 29th February 2012, 07:25 PM   #815
sippy is offline sippy  United Kingdom
diyAudio Member
 
Join Date: Jun 2008
Aye Tea-Bag (love the id btw (being a yorkshire man and all)).......I've done proto work on 2 and 4 stroke porting, but its been a while since I've built an amp. V2 would allow me to help proto and if it works as a single channel, i'd have a ps only needing a second channel to be added.
My offer still stands.
  Reply With Quote
Old 29th February 2012, 07:36 PM   #816
diyAudio Member
 
Join Date: Jan 2006
Location: North west England
Ihquam:

I too aim for 2 balanced monoblocks, and 100W per channel. I've looked at your heatsink tunnel with fan and it's a cracking idea. So I'm going to emulate that. Have you calculated any bias and voltage ratings?

Chalk
  Reply With Quote
Old 29th February 2012, 08:54 PM   #817
SRMcGee is offline SRMcGee  United States
diyAudio Member
 
SRMcGee's Avatar
 
Join Date: May 2004
Location: Wynnewood, PA
Folks:

As excited as I am about this project, I confess that my confusion about how to heatsink a 100w/ch F5T is leading me to second-guess reserving V3 Output Boards; perhaps using the single FET output boards and spreading the heat across a larger physical space would be a more stable solution (but who needs a pair of HiFi2000 5U 500mm monoblock amps?). I've been spending a lot of time trying to identify adequate cost-effective solutions but am hampered by massive ignorance. My hope is that those of you who know what you are doing can provide some heatsinking guidance before Andy closes his pending group buy.

Regards,
Scott
__________________
Good decisions are derived from experience; experience is derived from bad decisions.
  Reply With Quote
Old 29th February 2012, 09:34 PM   #818
diyAudio Member
 
Join Date: Jan 2010
Location: Harrow, UK
I wonder how many people will actually bias to Class A @ 100W???
  Reply With Quote
Old 29th February 2012, 11:06 PM   #819
Horio is offline Horio  United States
Newbie
diyAudio Member
 
Horio's Avatar
 
Join Date: Mar 2010
Location: Seattle
I'm thinking of shooting for around 100W into 8 ohms Class A with my balanced mono-blocks. Going balanced makes it a bit easier.
  Reply With Quote
Old 1st March 2012, 12:00 AM   #820
rdk845 is offline rdk845  United States
diyAudio Member
 
Join Date: Jun 2006
Quote:
Originally Posted by Horio View Post
I'm thinking of shooting for around 100W into 8 ohms Class A with my balanced mono-blocks. Going balanced makes it a bit easier.
Hi Horio,

I'm probably wrong here, but at given heatsink capacity and given transformer VA rating, wouldn't single ended better in getting higher class A power, while balanced better in getting better overall power? Even though you get to use lower rail voltage at given overall taget power with balanced so higher bias current per device at given heatsink and transformer capacity, in SE mode 4 pairs of devices are in pararell adding up the current, while in balance mode there are only 2 of 2 pair devices in parallel to add the current against speakers? I'd appreciate your correction if I'm wrong.

Thanks!
  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
F5 clone boards (inc PSU boards) Tazzz Swap Meet 39 7th June 2014 07:02 AM
F5 Turbo is posted Nelson Pass Pass Labs 635 6th April 2014 10:51 AM
F5 turbo problems Rob Dingen Pass Labs 17 11th January 2013 08:38 PM
F5 Turbo ............. if only !!!!!! a.wayne Pass Labs 23 21st January 2012 02:24 AM
UGS Boards and F5 boards DUC985 Swap Meet 0 7th January 2009 07:21 PM


New To Site? Need Help?

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