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

Solid State Talk all about solid state amplification.

The AMNESIS amp: a good amplifier, like a gentleman, has no memory.
The AMNESIS amp: a good amplifier, like a gentleman, has no memory.
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 16th September 2018, 01:16 PM   #251
maxlorenz is offline maxlorenz  Chile
diyAudio Member
 
maxlorenz's Avatar
 
Join Date: Oct 2003
Location: osorno , Chile
Thank you, dear Symon, for your concern.

No. C38 was never fitted. Though the 4 resistors in parallel may have some capacitance which could affect FB.

Now I switched back to my highly regarded current-FB amp, which has very high slew-rate: no comparison to my beloved Amnesis, which has much lower slew-rate (slow amp) with regards to impact of the notes and dynamics; better sound's envelope. I also notice that Amnesis has more clarity and definition, though with certain software I still can hear some "grain". I have to fit the right complementary P-MOSFET.

A pity my knowledge and savoir faire is so limited...I guess it is this way that we learn.

Best wishes,
M.
  Reply With Quote
Old Today, 01:42 PM   #252
maxlorenz is offline maxlorenz  Chile
diyAudio Member
 
maxlorenz's Avatar
 
Join Date: Oct 2003
Location: osorno , Chile
Sorry for the silence.
I've been trying to de-bug it step by step. So far I think that:

The active CCS is not the problem.
Connecting the drivers directly (without cascodes) made oscillation worsen.
The parallel FB resistors are not the problem. Reducing FB resistor to 10k did nothing...
Different bypasses strategies did not improve it.
The type of bootstrap capacitor does not affect the oscillation.
Adding stopper resistors to input cascode JFETs does nothing to stop it...

I have a couple more tricks to try on the cascoded VAS, which is probably the culprit, and then I will be out of ideas. Probably will assemble everything, with the right P-MOSFET and pray to my local electric deity...I hope a professional PCB will have "negligible" parasitics and none of these will appear...

For now, I am catching up with my digital projects
A big mess...
Attached Images
File Type: jpg SCRAMBLER INTERPOLATOR SD.jpg (945.4 KB, 8 views)

Last edited by maxlorenz; Today at 01:48 PM.
  Reply With Quote

Reply


The AMNESIS amp: a good amplifier, like a gentleman, has no memory.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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
new memory for PC AndrewT Everything Else 36 24th October 2015 10:09 AM
down the memory hole? tomtt Everything Else 16 9th September 2014 01:27 PM
My memory is failing me I think?? Moondog55 Analogue Source 3 31st January 2011 03:57 AM
LCR and of course Memory Resistor impsick Parts 2 3rd May 2008 08:30 AM
Notebook Memory eag Swap Meet 4 24th April 2006 04:20 AM


New To Site? Need Help?

All times are GMT. The time now is 06:58 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki