IRFP9610 Heat Sink Aleph 2 Question (and others) - Page 2 - 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 16th February 2003, 08:05 PM   #11
grataku is offline grataku  United States
diyAudio Member
 
Join Date: Dec 2000
Location: -
Default Re: Caps question

Quote:
Originally posted by Asen
What caps does Mr. Pass use in the original ALEPHs? Black Gates?

Thanks
I don't think Nelson cares all that much about components as long as they have decent specs, if you look at the XA200 pics he posted here it's all digikey type parts, like panasonics PP for ac coupling etc. The whole thing just naturally sounds good because the design is good. If you added black gates here and there it would probably sound sublime that's why I started the BG bulk purchase.
  Reply With Quote
Old 16th February 2003, 08:16 PM   #12
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
When looking at your PCB, it's hard not to notice that you are using very long leads to components and also dress them in a sort of plastic jacket. First of all, it is all extra work and actually it is something not desirable. Just trim them as short as possible (especially for TO-92 semis and mica caps) and don't be afraid to rest them on a board.
This is not production and you should pay different kind of attention to small details.
__________________
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 17th February 2003, 12:12 PM   #13
Jay is offline Jay  Indonesia
diyAudio Member
 
Join Date: Feb 2003
Location: Jakarta
Hi Kristian,

The IRFP9610 has it's Drain connected to it's flange. The Drain is the center pin (I don't know the other type with an extra pin). The Drains of each differential pairs do not meet each other. The Sources do.

I don't know the insulator you use for the component leads, but using materials similar to cable insulators, I used to be able to locate the degradation in the sound quality. Disagree? Well, remove from one channel and compare. If you can't hear the improvement, don't sue me.

I also used to mount components off the board like yours. Sometimes even times longer. Especially for expensive capacitors and resistors. This is to allow for the components to migrate from PCB to PCB.

Hey, where do you get that Pass Labs' PCB? Damm, I don't have a credit card!
  Reply With Quote
Old 18th February 2003, 08:57 AM   #14
diyAudio Member
 
Join Date: Aug 2002
Location: Jakarta, INDONESIA
Send a message via ICQ to TjongKristian
Default PCB

Hi Jay, if you are interested in the PCB I have a pair that I can let go. You can contact me via e-mail.
  Reply With Quote
Old 18th February 2003, 10:11 AM   #15
Jay is offline Jay  Indonesia
diyAudio Member
 
Join Date: Feb 2003
Location: Jakarta
Many thank's, Kristian. But I couldn't reach your e-mail.
  Reply With Quote
Old 18th February 2003, 10:33 AM   #16
diyAudio Member
 
Join Date: Aug 2002
Location: Jakarta, INDONESIA
Send a message via ICQ to TjongKristian
Default Ooops

Peter,
Thank you for your advice.

Jay,
You should be able to email me now.
  Reply With Quote
Old 19th February 2003, 05:58 AM   #17
diyAudio Member
 
Join Date: Sep 2001
Location: Salt Lake City
Using that plastic tubing over the parts leads my add some capacitance that would be undesrible in the circuit. The heatsinks are also not really needed but do look nice. I used different sinks on mine as the photo below shows......
Mark
Attached Images
File Type: jpg pcb webcopy.jpg (37.7 KB, 568 views)
  Reply With Quote
Old 22nd February 2003, 06:59 PM   #18
Jay is offline Jay  Indonesia
diyAudio Member
 
Join Date: Feb 2003
Location: Jakarta
Quote:
Originally posted by Mark A. Gulbrandsen
The heatsinks are also not really needed but do look nice. I used different sinks on mine as the photo below shows......
The IRF on current source passes higher current than IRF in the differential pairs, and sure will get hotter (so you may want to add heatsink here). The higher the current usually the better the performance (so you won't want to add resistance to offset the DC in current source).

MOSFET can withstand a higher temperature than it will experience here, but ("they" say) will reduce the MOSFET life. The last statement may be useless. What you may want to hear is whether such temperature (I think more than 100C) will degradate the performance to an audible degree. Because the MOSFET will be damaged or replaced long before it's usefull life anyway.
  Reply With Quote
Old 22nd February 2003, 07:55 PM   #19
Nicwix is offline Nicwix  Australia
diyAudio Member
 
Join Date: Dec 2001
Location: Sydney, Australia
Default Power disipated by the IRF9610s

My back of the envelope calculations are as follows:

Firstly the diff. pair's current source:

The IRF9610's source is around 6 Volts below the +Rail (assuming Vgs = 3 Volts)
Therefore with a 220 ohm resistor, current is around 27mA

The drain is 3 Volts (Vgs) above ground.

Assuming the rails are +/- 15 Volts, then Vds = 15 - 6 - 3 = 6 volts, then:
Power = 6 Volts x 27 mA = 0.16 Watts

Secondly the diff. pair:

The drain of each of the diff. pair is around 4.6 Volts above the negative rail, so they have a Vds of around 13.5 Volts, but shate the current, so:
Power = 13.5 Volts x 13.5 mA = 0.18 Watts each

All pretty much the same, all inconsequential => no heatsink necessary on any of them.

Anyone like to check my calcs - (I hope my estimates of the voltages are right!)

Nic
  Reply With Quote
Old 22nd February 2003, 08:19 PM   #20
Jay is offline Jay  Indonesia
diyAudio Member
 
Join Date: Feb 2003
Location: Jakarta
I will look at your calculation later, but why not try Khircoff first?
  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
Aleph P1.7 heat sink? sugano Pass Labs 1 11th July 2006 02:56 PM
Aleph X heat sink thread Peter Daniel Pass Labs 306 24th July 2003 12:17 PM
Aleph 2 Heat Sink (chassis) TjongKristian Pass Labs 32 21st December 2002 05:19 PM
Aleph 3 Heat sink capability raincheck Pass Labs 27 25th June 2002 03:14 AM


New To Site? Need Help?

All times are GMT. The time now is 12:02 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