Burning Amp BA-3
 User Name Stay logged in? Password
 Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read Search

 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
BDP
diyAudio Member

Join Date: Apr 2002
Location: SE Washington State
Quote:
 Originally Posted by nkdk Hi Thx for the answers I have swap p1-p2 too 1kΩ and the volts over R10-11 is 1,0 volts now, then this okay , there is running 45 ma , but how about Q1-2 there is only running 4 ma,is that a problem ?? 600 Ω drain resistor? , there is no 600 Ω resistor only 10 Ω with a 100 Ω pot Nkdk
The 4 ma is why you had to increase the drain resistance. I think the Idss was specified to be 10 ma. Problem, I don't know? Have a listen and see what you think.

The 600 ohm was the combined total drain resistance, but that doesn't matter now that you have put in the new pot.

 21st July 2012, 03:11 AM #842 nkdk   diyAudio Member   Join Date: May 2009 Hi Okay thx, i give it a try and make some listen tests, and ma by fiddle with q1-2 Nkdk
 2nd September 2012, 05:39 PM #843 Pwrs diyAudio Member   Join Date: Nov 2011 Measurements Hi there, i was hoping that someone could point me in the right direction regaring some measurements on the front end. I have a dip/overshoot on the negative curve that i would like to understand. Voltage on the resistors are: Left R3/R4 = 64.66 - 64.69mV R10 = 1.042 V R11 = 1.037 V Right R3/R4 = 65.08 - 65.10mV R10 = 1.038 R11 = 1.036 Here are som waveforms from the scope, the blue ones are for left channel and red for right. The input is 2Vp-p @ 5k, 50k and 100kHz. Measured across R13. 2Vpp_5Khz_Left.gif2Vpp_5Khz_Right.gif 2Vpp_50kHz_left.gif2Vpp_50kHz_Right.gif 2Vpp_100Khz_Left.gif2Vpp_100Khz_Right.gif
 2nd September 2012, 06:27 PM #844 Zen Mod   Official Court Jester diyAudio Member     Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain fiddle with P3 __________________ 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
noSmoking
diyAudio Member

Join Date: May 2010
Location: Texas
Hi
Would some one help me out here I don't know where to connect the connection from the ba 3 to the bias board ,Like what connects to D+ or D- or S
Thanks
NS
Attached Images
 img018.jpg (318.9 KB, 437 views)

tinitus
diyAudio Moderator R.I.P.

Join Date: Nov 2005
Quote:
 Originally Posted by noSmoking ......Like what connects to D+ or D- or S Thanks NS
according to new BA3 frontend schematic, +D is signal out(to power amp)
I reckon -D would be signal ground

S ...? I only find that on old BA1 frontend, so I guess it goes nowhere now with new BA1/BA3 ?

 7th September 2012, 07:28 PM #847 Zen Mod   Official Court Jester diyAudio Member     Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain who made these pcbs ? __________________ 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
 7th September 2012, 09:01 PM #848 generg   diyAudio Member     Join Date: Jul 2009 Location: Near Frankfurt Diyaudio store Output of One side of the BA-3 frontend to D (GS) and ground G of One bias board, the same with the other output of the BA-3 Frontend and the other bias board. D+ and D- are Only for the bias and S is the feedback sensing the bias current. __________________ and the First Wtt is......a really First Class PSS Idea Last edited by generg; 7th September 2012 at 09:13 PM.
 7th September 2012, 09:06 PM #849 Zen Mod   Official Court Jester diyAudio Member     Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain so there must be a blog somewhere ? D+ and D- are reminding me on BA3 balanced sorry - I just didn't follow birth of pcbs __________________ 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
 7th September 2012, 09:20 PM #850 generg   diyAudio Member     Join Date: Jul 2009 Location: Near Frankfurt Unfortunately Nelson's PDF and the bias and output board nomenclature are a bit different I always had to think twice when connecting these parts and often.......did it the wrong way. In this case D+and D- refer to the drains of the upper and lower outputstage and their bias. D (GS) !GS means gainstage, is the real input and the ground point nearby is for he shielded cable. __________________ and the First Wtt is......a really First Class PSS Idea

 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 Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Site     Site Announcements     Forum Problems Amplifiers     Solid State     Pass Labs     Tubes / Valves     Chip Amps     Class D     Power Supplies     Headphone Systems Source & Line     Analogue Source     Analog Line Level     Digital Source     Digital Line Level     PC Based Loudspeakers     Multi-Way     Full Range     Subwoofers     Planars & Exotics Live Sound     PA Systems     Instruments and Amps Design & Build     Parts     Equipment & Tools     Construction Tips     Software Tools General Interest     Car Audio     diyAudio.com Articles     Music     Everything Else Member Areas     Introductions     The Lounge     Clubs & Events     In Memoriam The Moving Image Commercial Sector     Swap Meet     Group Buys     The diyAudio Store     Vendor Forums         Vendor's Bazaar         Sonic Craft         Apex Jr         Audio Sector         Acoustic Fun         Chipamp         DIY HiFi Supply         Elekit         Elektor         Mains Cables R Us         Parts Connexion         Planet 10 hifi         Quanghao Audio Design         Siliconray Online Electronics Store         Tubelab     Manufacturers         AKSA         Audio Poutine         Musicaltech         Aussie Amplifiers         CSS         exaDevices         Feastrex         GedLee         Head 'n' HiFi - Walter         Heatsink USA         miniDSP         SITO Audio         Twin Audio         Twisted Pear         Wild Burro Audio

 Similar Threads Thread Thread Starter Forum Replies Last Post Variac Pass Labs 356 17th January 2017 11:54 PM Nelson Pass diyAudio.com Articles 39 14th October 2016 11:36 AM Nelson Pass diyAudio.com Articles 3 24th October 2011 02:53 AM jdubs Swap Meet 0 23rd March 2011 03:16 AM Eric Weitzman Swap Meet 15 17th February 2010 02:35 AM

 New To Site? Need Help?

All times are GMT. The time now is 07:04 AM.