oneplustwo Aleph X build thread - Page 14

Zen Mod · 14th January 2013, 10:16 AM

desolder (pull out ) either R29 od R47 and then try entire procedure again

something is wrong with your measurement - voltage across R29 and R47 must be the same

oneplustwo · 15th January 2013, 05:23 AM

Doh! Sorry, fat fingered one number.

D5: 8.92V
R47: 4.83V
R29: 4.84V
R30: 3.0V

oneplustwo · 06:33 AM

Slightly different numbers after an hour of warm up if it makes a difference:

D5: 8.99V
R47: 4.98V
R29: 4.99V
R30: 3.1V

During this commercial break... can I also confirm that it's important to turn on your source BEFORE turning on the amps? I noticed some pretty big turn on thump when I didn't initially have my source already one. Woofers extended outward pretty far... scared me a little bit but doesn't seem to have done any damage.

Zen Mod · 15th January 2013, 09:22 AM

just do what I wrote in #131

regarding thump - that's normal , it doesn't have anything with your amp , but with common logic

oneplustwo · 15th January 2013, 03:57 PM

Great, I'll give that a try tonight. Thanks for your help! I'm not really sure why both resistors are there in the first place... perhaps just power handling so as to not require higher wattage resistors? Or perhaps for people like me who just need an easy way to get to zero absolute DC offset?

Zen Mod · 15th January 2013, 04:10 PM

dunno ;

someone was keen to put plenty of parts , probably to invoke better sound ?

properly sized R30 and Rp1 are all you need there , covering all possible variations

oneplustwo · 12:47 AM

Removed R47 and now when I turn the pots the OTHER direction fully, I can only get to +2.5 and +1.5 V. So it looks like I need to add another resistor back in. I should be able to find something in the ballpark. Any suggestions? Maybe something in the 100R range?

Also, I noticed the heat distribution is backwards now... although much more even now.

Zen Mod · 12:59 AM

what +2V5 and what +1V5 ?

edit : I'm going to sleep now

read ya tomorrow

Zen Mod · 17th January 2013, 01:07 AM

just thinking

if you now have out to gnd offset in positive (instead of previous negative ) , just put R47 back

but - this time not 475R ; put 1K for start then - if necessary - 910R or 820R

good night .....

oneplustwo · 17th January 2013, 02:14 AM

Yes, that was what I was thinking. I'll try 1K first as you suggested. Thanks!

BTW, after fully warmed up, I have 1.6V and .3 V (positive on both) now. Seems to not be drifting anymore.

14th January 2013, 10:16 AM	#131
Zen Mod diyAudio Member Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain	desolder (pull out ) either R29 od R47 and then try entire procedure again something is wrong with your measurement - voltage across R29 and R47 must be the same __________________ my Papa is smarter than your Nelson ! tnx to clean thread ; Cook Book ; PSM LS Cook Book ; Baby Diyaudio FORUM ; Mighty ZM's Bloggg;I'm dumb

15th January 2013, 05:23 AM	#132
oneplustwo 1.21 Gigawatts?! diyAudio Member Join Date: Apr 2009 Location: San Francisco	Doh! Sorry, fat fingered one number. D5: 8.92V R47: 4.83V R29: 4.84V R30: 3.0V __________________ My Projects

15th January 2013, 06:29 AM	#133
oneplustwo 1.21 Gigawatts?! diyAudio Member Join Date: Apr 2009 Location: San Francisco	Slightly different numbers after an hour of warm up if it makes a difference: D5: 8.99V R47: 4.98V R29: 4.99V R30: 3.1V During this commercial break... can I also confirm that it's important to turn on your source BEFORE turning on the amps? I noticed some pretty big turn on thump when I didn't initially have my source already one. Woofers extended outward pretty far... scared me a little bit but doesn't seem to have done any damage. __________________ My Projects Last edited by oneplustwo; 15th January 2013 at 06:33 AM.

15th January 2013, 09:22 AM	#134
Zen Mod diyAudio Member Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain	just do what I wrote in #131 regarding thump - that's normal , it doesn't have anything with your amp , but with common logic __________________ my Papa is smarter than your Nelson ! tnx to clean thread ; Cook Book ; PSM LS Cook Book ; Baby Diyaudio FORUM ; Mighty ZM's Bloggg;I'm dumb

15th January 2013, 03:57 PM	#135
oneplustwo 1.21 Gigawatts?! diyAudio Member Join Date: Apr 2009 Location: San Francisco	Great, I'll give that a try tonight. Thanks for your help! I'm not really sure why both resistors are there in the first place... perhaps just power handling so as to not require higher wattage resistors? Or perhaps for people like me who just need an easy way to get to zero absolute DC offset? __________________ My Projects


	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

15th January 2013, 04:10 PM	#136
Zen Mod diyAudio Member Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain	dunno ; someone was keen to put plenty of parts , probably to invoke better sound ? properly sized R30 and Rp1 are all you need there , covering all possible variations __________________ my Papa is smarter than your Nelson ! tnx to clean thread ; Cook Book ; PSM LS Cook Book ; Baby Diyaudio FORUM ; Mighty ZM's Bloggg;I'm dumb

17th January 2013, 12:44 AM	#137
oneplustwo 1.21 Gigawatts?! diyAudio Member Join Date: Apr 2009 Location: San Francisco	Removed R47 and now when I turn the pots the OTHER direction fully, I can only get to +2.5 and +1.5 V. So it looks like I need to add another resistor back in. I should be able to find something in the ballpark. Any suggestions? Maybe something in the 100R range? Also, I noticed the heat distribution is backwards now... although much more even now. __________________ My Projects Last edited by oneplustwo; 17th January 2013 at 12:47 AM.

17th January 2013, 12:56 AM	#138
Zen Mod diyAudio Member Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain	what +2V5 and what +1V5 ? edit : I'm going to sleep now read ya tomorrow __________________ my Papa is smarter than your Nelson ! tnx to clean thread ; Cook Book ; PSM LS Cook Book ; Baby Diyaudio FORUM ; Mighty ZM's Bloggg;I'm dumb Last edited by Zen Mod; 17th January 2013 at 12:59 AM.

17th January 2013, 01:07 AM	#139
Zen Mod diyAudio Member Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain	just thinking if you now have out to gnd offset in positive (instead of previous negative ) , just put R47 back but - this time not 475R ; put 1K for start then - if necessary - 910R or 820R good night ..... __________________ my Papa is smarter than your Nelson ! tnx to clean thread ; Cook Book ; PSM LS Cook Book ; Baby Diyaudio FORUM ; Mighty ZM's Bloggg;I'm dumb

17th January 2013, 02:14 AM	#140
oneplustwo 1.21 Gigawatts?! diyAudio Member Join Date: Apr 2009 Location: San Francisco	Yes, that was what I was thinking. I'll try 1K first as you suggested. Thanks! BTW, after fully warmed up, I have 1.6V and .3 V (positive on both) now. Seems to not be drifting anymore. __________________ My Projects

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Loudspeaker Build Thread	Hsmeets	Multi-Way	67	15th August 2012 01:30 PM
oneplustwo F5 build thread	oneplustwo	Pass Labs	251	30th May 2012 09:36 PM
oneplustwo DCB1 Black, White and Red build thread	oneplustwo	Pass Labs	1	26th February 2012 06:11 AM
aikido build thread-	nate	Tubes / Valves	1	27th February 2009 05:01 AM
Dan's Aleph Build Thread	monarodan	Pass Labs	19	14th February 2007 11:06 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read