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.

The diyAudio First Watt M2x
The diyAudio First Watt M2x
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 14th May 2019, 09:32 PM   #1851
MEPER is offline MEPER  Denmark
diyAudio Member
 
Join Date: Nov 2017
Location: Copenhagen
Does an explanation of the schematic in details exist somewhere like a Burning Amp video?
There is some info at Firstwatt but it is very high level?
E.g. diode D1, D2, D3.....this construction looks a bit asymmetrical (everything else looks symmetrical)?
There is also a kind of local feedback from output back to input of mosfets?
Then there is the special optical bias with the two 1.2V voltage references.
Maybe I will find out slowly bit after bit...….
  Reply With Quote
Old 14th May 2019, 10:07 PM   #1852
Mark Johnson is offline Mark Johnson  United States
diyAudio Member
 
Mark Johnson's Avatar
 
Join Date: May 2011
Location: Silicon Valley
Not in this thread, no. The earlier threads about the First Watt product called "M2" (M2x minus the daughter board options) might contain what you want:

GB Pass M2 Clone Boards with 120mm UMS spacing by Tea-Bag

Official M2 schematic

I don't know of a YouTube video about the inner workings of the M2.

It may help to remember that First Watt sold a bunch of M2s to paying customers for pretty big bucks (like $4000 per amp). It got good reviews in the audio press. Then when Nelson Pass decided to stop selling it, he published the schematic here so that DIYers could make themselves a copy if they wanted to. He might not have felt any urgency to "explain" the amp since (a) we already know it sounds great, nobody disputes this; (b) here is the secret schematic that makes it sound great; (c) if you want an amp that sounds like the M2, do this.

_

Last edited by Mark Johnson; 14th May 2019 at 10:18 PM. Reason: final paragraph
  Reply With Quote
Old 15th May 2019, 05:33 AM   #1853
MEPER is offline MEPER  Denmark
diyAudio Member
 
Join Date: Nov 2017
Location: Copenhagen
Ok.....thank you! I will read it in details…….
  Reply With Quote
Old 15th May 2019, 05:03 PM   #1854
MEPER is offline MEPER  Denmark
diyAudio Member
 
Join Date: Nov 2017
Location: Copenhagen
How many hours of work from idea to a final prototype?


$4000 is not that much. Even at DIY if you build a solid power supply and get a nice chassis from HiFi2000 etc. the first $1000 is spend easily.
  Reply With Quote
Old 15th May 2019, 08:00 PM   #1855
Zen Mod is offline Zen Mod  Serbia
Official Court Jester
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
The diyAudio First Watt M2x
FW amps are cheap
__________________
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 16th May 2019, 01:57 AM   #1856
elwood625 is offline elwood625  United States
diyAudio Member
 
Join Date: Jan 2013
Location: Illinois
Marketing people call it Value Priced. I'm building one and with the diyAUDIO store PC boards, 4U enclosure and parts bought from DigiKey and Mouser for 5 of the six daughter boards, less than $700. After I add bling, just under $1000 and will look good enough for me to be proud of the build.
When I'm done, all I have to do is remove the top cover, loosen/tighten 8 little nuts, and I can turn it into one of 5 different sounding amps including the original M2.
I call it a bargain. The hardest part is finding a 37K resistor
  Reply With Quote
Old 16th May 2019, 02:24 AM   #1857
KevinHeem is offline KevinHeem  United States
diyAudio Member
 
KevinHeem's Avatar
 
Join Date: Nov 2007
Location: Hudsonville, MI
The diyAudio First Watt M2x
How about a 27K and 10K in series?
  Reply With Quote
Old 16th May 2019, 02:50 AM   #1858
Dennis Hui is offline Dennis Hui  Canada
Hoopy Frood
diyAudio Member
 
Join Date: Aug 2002
Location: Toronto, Canada
The diyAudio First Watt M2x
That value need not be exact and 36.5K and 37.4K are readily available.
__________________
We are fearless amplifier builders. A little heat doesn't scare us at all.
- NP 2002
  Reply With Quote
Old 16th May 2019, 03:21 AM   #1859
Mark Johnson is offline Mark Johnson  United States
diyAudio Member
 
Mark Johnson's Avatar
 
Join Date: May 2011
Location: Silicon Valley
Perhaps your personal circuit designer might tell you whether any of these are acceptable: (LINK)
  Reply With Quote
Old 16th May 2019, 04:47 AM   #1860
MEPER is offline MEPER  Denmark
diyAudio Member
 
Join Date: Nov 2017
Location: Copenhagen
I forgot to order the 37k but had some 39k...…..which I used together with the 20k pots. I feel confident that this gives enough room for offset adjustment. The boards just looks a bit "messy" now as one resistor is a "normal" Vishay with color bands and all the others are the brown Vishay Dale RN55......will see if I can live with that :-)
  Reply With Quote

Reply


The diyAudio First Watt M2xHide 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
What make and model are the original drivers in Wilson Watt&Puppy 7 (WATT) aguiarrj Multi-Way 17 24th June 2017 10:39 PM
2.3 watt x 4 or 5 watt x2 SET amplifier using DECWARE Zkit1 and Zkit4 schematics Redwolf92 Tubes / Valves 12 29th October 2014 10:19 PM
diyaudio moderator vs diyaudio member Leolabs Everything Else 6 18th June 2006 08:19 AM


New To Site? Need Help?

All times are GMT. The time now is 11:29 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki