IRF 230 or IRFP 140, what's better for AlephX ? - 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 12th August 2002, 02:13 PM   #1
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Default IRF 230 or IRFP 140, what's better for AlephX ?

I have still IRF230 mosfets in TO3 cases (which I was using for A75) and IRFP140 mosfets (TO 247 cases) which I bought recently. What would be a better choice for Aleph X with 20V rails?
__________________
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 12th August 2002, 02:15 PM   #2
Warp Engineer
On Holiday
 
AudioFreak's Avatar
 
Join Date: Oct 2001
Location: Queensland, Australia
IRFP140
  Reply With Quote
Old 12th August 2002, 02:19 PM   #3
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
That's what I thought, thanks.
__________________
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 12th August 2002, 04:09 PM   #4
diyAudio Member
 
Join Date: Jan 2001
Location: Scandinavia
Default I think it is not quite that simple

First of all, these are different form factor devices. The P model will be normally be better at transferring heat to sink except that you have the TO3 version which will be better still at about a square inch of contact area.

Secondly, it will depend on many factors -- one of my methods for sorting devices is to first look for devices which have relatively high on-resistance as this often goes hand in hand with low gate charge, not to mention gate charge which does not vary all that much with gate voltage.

'40 devices are usually more heavily optimized for swithing than '30 devices. Switching transistors are not optimized for linearity.

100 series devices are optimized for higher currents than 200 series devices. This is not necessarily an advantage.

What I have learned (from others) is that IRF units are typically not considered to be the best audio devices around -- where only a few manufacturers seem to make them sound good (with Pass being perhaps the most well known proponent). Japanese devices receive more positive "street credibility".

The question is thus one of taste, and I suspect both devices can be cajoled into sounding very good. There have been similar device discussions in the past where even NP has participated. The short answer is that it probably does not matter that much what you choose (an answer which I personally don't like).

Next time I purchase devices, I will try Japanese.

In your case, I would expect the 230's to sound smoother and based on other posts, the 140's to possibly have more robust bass.

Petter
  Reply With Quote
Old 12th August 2002, 04:24 PM   #5
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
So we are back to square one. I have enough of both devices and mounting is not a problem either. The amps would be used for mids and highs, so optimal sound would be preffered in that region. So you say that 230 would be smoother?....Maybe this is a better choice then.

As to Japanese devices, the price is still an issue, especially if you buying more for matching.
__________________
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 12th August 2002, 04:57 PM   #6
diyAudio Member
 
Join Date: Jan 2001
Location: Scandinavia
Price:

If you like me have already purchased and standardized/matched you are kind of locked in

Be sure to let us know what your findings are if you decided to try both.

Petter
  Reply With Quote
Old 12th August 2002, 05:20 PM   #7
Coulomb is offline Coulomb  England
diyAudio Member
 
Coulomb's Avatar
 
Join Date: Jul 2002
Location: Ancaster, Ontario
Default Re: AelphX

Please excuse my iognorance yet again. What is an AelphX, I see constant references to this Mystery Amp. Where can I find specs, Designs, Schematics, anyone making PCB's. I had always assumed the X stood for the version number, instead of the full name.

Anthony
  Reply With Quote
Old 12th August 2002, 05:28 PM   #8
skaara is offline skaara  Slovenia
diyAudio Member
 
Join Date: Jun 2002
Location: Europe, Slovenia
There are no original schematics/pcbs for that amp.. Ppl are trying to make an amp like the original amp with some speculation and their own knowlege, ill make my alephx when there will be original schematic, if it will ever be?
  Reply With Quote
Old 12th August 2002, 05:30 PM   #9
Coulomb is offline Coulomb  England
diyAudio Member
 
Coulomb's Avatar
 
Join Date: Jul 2002
Location: Ancaster, Ontario
Default Re: IRFP140

Peter why do you prefer the IRFP140 over the 240 and 244 again? Do you find there are sonic differences or is it due to the differences in the specs? If so over than voltage ratings, what do you find objectionable?

Anthony
  Reply With Quote
Old 12th August 2002, 05:32 PM   #10
Coulomb is offline Coulomb  England
diyAudio Member
 
Coulomb's Avatar
 
Join Date: Jul 2002
Location: Ancaster, Ontario
Quote:
.. Ppl are trying to make an amp like the original amp with some speculation and their own knowlege
Well I really like the Pass X200, I was thinking of trying to squeeze more than 100 Watts out of an Aelph II.

Anthony
  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
new irfp mosfets elviukai Pass Labs 17 16th March 2007 08:54 AM
IRFP 240 for sale dhole Swap Meet 8 20th July 2005 01:24 PM
irfp Substitute Ipanema Parts 1 13th January 2005 01:29 PM
Yor Opinion on this MOS-Amp (+-80V IRFP[9]240) tab30 Solid State 7 1st December 2003 12:27 PM
Irfp 240 !!!!!!!!!! jeclk Pass Labs 5 11th November 2003 05:00 PM


New To Site? Need Help?

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