Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Pass Labs This forum is dedicated to Pass Labs discussion.

Inductor Loaded De-Lite
Inductor Loaded De-Lite
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 August 2019, 10:52 PM   #11
Nelson Pass is offline Nelson Pass  United States
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
Inductor Loaded De-Lite
That part is still rated at 200W with the case at 75 deg C.

If you have a big sink you might get away with it.

On the other hand, something less that 50V is probably appropriate....
  Reply With Quote
Old 24th August 2019, 11:51 PM   #12
Jenghis is offline Jenghis
diyAudio Member
 
Join Date: Jan 2019
So if the idle current is set to 2.2A, and there is 24V or slightly less at the drain of the MOSFET, then power dissipation at idle should be approximately 53W correct? That will require a big heatsink indeed...
  Reply With Quote
Old 25th August 2019, 04:06 AM   #13
PRR is offline PRR  United States
diyAudio Member
 
PRR's Avatar
 
Join Date: Jun 2003
Location: Maine USA
If the idle is 2.2A, and the load is 8r, you can only swing 17.6V across the load, thus across the device. Taking 2.2V on the resistor and another couple volts lost in the transformer, you want 22V supply, not 50V. (This gives near 20W out for 50W total dissipation.)

The resistors (lamps) are MUCH more lossy, hence the higher voltage for that affair.
  Reply With Quote
Old 25th August 2019, 06:05 AM   #14
Jenghis is offline Jenghis
diyAudio Member
 
Join Date: Jan 2019
Quote:
Originally Posted by PRR View Post
If the idle is 2.2A, and the load is 8r, you can only swing 17.6V across the load, thus across the device. Taking 2.2V on the resistor and another couple volts lost in the transformer, you want 22V supply, not 50V. (This gives near 20W out for 50W total dissipation.)

The resistors (lamps) are MUCH more lossy, hence the higher voltage for that affair.
Yes I see now that the inductor can make do with much lower voltage than a simple power resistor. It also looks like an inductor may actually be worth the huge added cost over light bulbs. Sounds to me like an 18VAC transformer is the way to go, if the same power supply filter can work with the lower voltage.
  Reply With Quote
Old 25th August 2019, 01:29 PM   #15
oks81 is offline oks81  Norway
diyAudio Member
 
Join Date: Jul 2014
Hello!
I have tested something similar with choke.
The transistor was an IRFP 240 and the choke Lundahl LL2733 with the two colis in series.

https://www.lundahltransformers.com/...heets/2733.pdf

I would not recomend use of smaller chokes, bigger is bether.
Attached Images
File Type: jpg Zen Choke loaded.jpg (242.3 KB, 184 views)
__________________
  Reply With Quote
Old 25th August 2019, 06:23 PM   #16
Jenghis is offline Jenghis
diyAudio Member
 
Join Date: Jan 2019
Quote:
Originally Posted by oks81 View Post
Hello!
I have tested something similar with choke.
The transistor was an IRFP 240 and the choke Lundahl LL2733 with the two colis in series.

https://www.lundahltransformers.com/...heets/2733.pdf

I would not recomend use of smaller chokes, bigger is bether.
Neat! That choke is huge! How did it sound?
  Reply With Quote
Old 26th August 2019, 01:46 PM   #17
oks81 is offline oks81  Norway
diyAudio Member
 
Join Date: Jul 2014
It was ok.
Had to use an 8ohm resistor in parallell with speakers to get more correct freq.responce as the damping is probaly quite low. Or should have built series filters for the speakers, this NP explains in First Watt article.

The nice thing with choke is that it dont give so much heat from bias, except from that probably just as good/bether to build F2 or ACA.

But it was fun building the amp and learning

You need big chokes to stop ripple from PSU, and to get som bass.
Smaller chokes and you get both PSU noice and not so much bass.
I would recommend even bigger than 400mH.

Think Pass used 1000mH on a construction? Am I wrong?

Best
oks
__________________
  Reply With Quote
Old 28th August 2019, 12:51 PM   #18
xrk971 is offline xrk971  United States
Got Foam?
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Metro DC area
Inductor Loaded De-Lite
This is all very similar to a MOFO. I have made a Mother of All MOFOs (MOAMOFO) with an IXYS running 4.3A and 37v. A CPU cooler with Noctua fan removes the circa 160w just fine.

Click the image to open in full size.
__________________
XRKaudio https://www.etsy.com/shop/XRKAudio
  Reply With Quote
Old 28th August 2019, 02:29 PM   #19
adason is offline adason  United States
diyAudio Member
 
adason's Avatar
 
Join Date: Nov 2004
Location: Maryland
Quote:
Originally Posted by xrk971 View Post
This is all very similar to a MOFO. I have made a Mother of All MOFOs (MOAMOFO) with an IXYS running 4.3A and 37v. A CPU cooler with Noctua fan removes the circa 160w just fine.

Click the image to open in full size.
That's amazing X! What speakers are you using it with? Sound? Have you got into tubes yet?
  Reply With Quote
Old 28th August 2019, 09:00 PM   #20
xrk971 is offline xrk971  United States
Got Foam?
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Metro DC area
Inductor Loaded De-Lite
Hi Adason,
Thanks! You should stop by my lab and have a listen sometime. The beer is included.

I am driving my usual power hungry 10F/RS225 transient perfect FAST speakers.

Although, recently I have been playing with an OB variant of the FAST speakers. You can see this amp plus a VHeX+ Class AB that I have been playing with on the OB.
Click the image to open in full size.
__________________
XRKaudio https://www.etsy.com/shop/XRKAudio

Last edited by xrk971; 28th August 2019 at 09:05 PM.
  Reply With Quote

Reply


Inductor Loaded De-LiteHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Difference between Dayton wire wound inductor vs. foil inductor andy2 Parts 8 21st February 2018 09:54 AM
Front loaded and back loaded horn DrWoofer.com Subwoofers 14 12th April 2016 08:32 PM
Back loaded, front loaded, Iím confused! Silent Screamer Subwoofers 23 4th May 2013 08:54 PM
Combination of Back-loaded Horn and Fron loaded horn?! ARIYAHOOR Full Range 26 1st June 2012 09:20 PM
Copper coil inductor vs. round core inductor tomchaoda Pass Labs 7 21st September 2011 04:42 AM


New To Site? Need Help?

All times are GMT. The time now is 10:12 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki