F4 power amplifier - Page 5 - 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 7th March 2007, 10:39 PM   #41
Formerly "jh6you". R.I.P.
 
Babowana's Avatar
 
Join Date: Jul 2006
Quote:
Originally posted by Nelson Pass


Commenting on the particular mis-match of the complementary
types, notice that the distortion is primarily second harmonic
on the amplifier and that the distortion vs power curve looks
just like a classic single-ended amp.

This imparts a particular sonic signature different from the
usual push-pull arrangement where the character is 3rd harmonic.


Thanks, I will go with mismatchd stones as I have had experience
of it with Zen V5. I will re-fill F1 having a bit higher rail voltages.
I would try to adjust R values, if necessary. I might be able to
manage this within few days when I get jfets, not using PCBs, but
applying P2P as usual. ~ ^^


  Reply With Quote
Old 7th March 2007, 11:59 PM   #42
diyAudio Member
 
jimmyd53's Avatar
 
Join Date: Jan 2006
Location: EUGENE, OREGON
Papa and Jon,

I am curious, since you are the only two who have listened to all the First Watt amps with Lowthers, as to which amp you personally like best ? Thanks.
James
  Reply With Quote
Old 8th March 2007, 12:51 AM   #43
Ipanema is offline Ipanema  Malaysia
diyAudio Member
 
Ipanema's Avatar
 
Join Date: Jun 2004
Location: KL
Quote:
Commenting on the particular mis-match of the complementary types, notice that the distortion is primarily second harmonicon the amplifier and that the distortion vs power curve looks just like a classic single-ended amp.
If I prefer more second harmonic, should I use higher mismatches device between PMOS and NMOS?

Mr. Pass, may I know why you prefer to use TL431 in place of the usual Vgs multiplier, which is more common in the push-pull stage with the added benefit of temperature feedback? How does F4 overcome the temperature instability?

I've just completed F2 and SL10. It just sound marvelous driving my Coral Flat 8A and now I'm addicted to build the F4. Thanks a lot Mr. Pass.

  Reply With Quote
Old 8th March 2007, 01:33 AM   #44
diyAudio Member
 
Join Date: Aug 2004
Location: Chicago area
Default First Watt Preference

Quote:
I am curious, since you are the only two who have listened to all the First Watt amps with Lowthers, as to which amp you personally like best ?
Aha! Down to the meat of it all. There is no right answer, and it is part dependent on your taste, part on your music, and your source.

The F1 is super clean and dynamic. If your source is lean, your music will be lean. If your source is rich, your music will be rich. It is the real truth machine, with nothing taken out and nothing added. Ruthlessly revealing.

The F2 adds some 2nd harmonic to this. On lean source material this sounds better than the F1. It is putting a little color in your music, and on dry material it is a pleasant addition. Some like that additional color, some do not. Your choice.

The F3 sounds has a very light touch of sweetness. Sounds more like a great tube amp than any solid state amp I have heard, except that it has the same basic tonal characteristics from highs to lows - something most tube amps dream about.

The F4 sounds like a cross between the F1 and the F3. Cleaner than the F2, a touch of sweetness, but the truth is still front and center. I have not heard this amp in my system (yet), so my thoughts about this may change. It is a very exciting product.

Nelson, with his greater experience, may be better able to describe all of these amps. But as to which is best? That is like saying vanilla is better than strawberry - it is a matter of what you enjoy. All of these bring something different to the table.

Not sure if that helps, but it is the best I can do.
__________________
Jon Ver Halen
Lowther-America
  Reply With Quote
Old 8th March 2007, 01:54 AM   #45
diyAudio Member
 
apassgear's Avatar
 
Join Date: Nov 2002
Location: Viña del Mar, Torreon
Jon, nice round up for the lot, I appreciate...Thanks
  Reply With Quote
Old 8th March 2007, 11:11 AM   #46
Vix is offline Vix  Yugoslavia
diyAudio Member
 
Vix's Avatar
 
Join Date: Nov 2003
Location: Somewhere on Planet Earth
Default Re: First Watt Preference

Quote:
Originally posted by Jon Ver Halen
The F4 sounds like a cross between the F1 and the F3. Cleaner than the F2, a touch of sweetness, but the truth is still front and center.
Uhm....Being just a follower, it shuold be cleaner than the F2. Jfet input brings a touch of sweetness, mismatched output devices bring some 2nd order harmonic, so it sounds a bit like single-ended....

Not having input Jfets at the moment, I was thinging about ways to make a simple buffer with irf610/irf9610 or similar, but..than it may loose a bit of sweetness. Using matched ouput devices should make it a bit more "clear" while unmatched provide more"romantic" sound?

Have I gone too far?

  Reply With Quote
Old 8th March 2007, 11:17 AM   #47
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
Quote:
Originally posted by Nelson Pass
Commenting on the particular mis-match of the complementary
types, ..................

Papa talk about mismatching between 240 and 9240

seems that everybody else talk about matching (or not ) between devices ;

this is -still-preferable............
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 8th March 2007, 11:58 AM   #48
diyAudio Member
 
bogdan_borko's Avatar
 
Join Date: Nov 2005
Location: serbia, zajecar
Great thanks to mr.Pass for shearing one of his ideas with us!


As I can see, the bias current trough the resistors network for the mosfets gates is about 1.4mA. Some wold say that`s funny! You have to drive the gate`s capacitances (3*IRFP240). How do you expain this mr.Pass?

Cheers!
  Reply With Quote
Old 8th March 2007, 12:04 PM   #49
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
Quote:
Originally posted by bogdan_borko
Great thanks to mr.Pass for shearing one of his ideas with us!


As I can see, the bias current trough the resistors network for the mosfets gates is about 1.4mA. Some wold say that`s funny! You have to drive the gate`s capacitances (3*IRFP240). How do you expain this mr.Pass?

Cheers!

AC or DC current ,when you think about gates?



anyway-look what's common there.........source or drain.....
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 8th March 2007, 04:29 PM   #50
diyAudio Member
 
Join Date: Feb 2001
Location: Columbia, SC
Default Re: Tube frontend maybe ?

Quote:
Originally posted by Jozef
Voltage is almost same as this linestage.
On one PCB maybe ?

If that tube will run well at that voltage, then by all means give it a try.

Grey
  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
Rockford Fosgate Power 20001 bd amplifier power rating?? pachoorion Car Audio 8 8th May 2011 10:49 PM
Power transformers versus amplifier output power..what is your option? destroyer X Solid State 38 9th May 2009 05:23 PM
McIntosh Power Amplifier Power Guard johnnyrt Solid State 2 23rd August 2007 10:22 PM
Output power for a power amplifier Progg70 Solid State 33 10th September 2006 08:44 AM
Amplifier 3000 Wats Rms Power + Smps Higcht Power Bestiality MARAVILLASAUDIO Class D 1 5th November 2004 04:06 PM


New To Site? Need Help?

All times are GMT. The time now is 12:35 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