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.

Aleph 30 - 1nF cap and Square Wave Shape
Aleph 30 - 1nF cap and Square Wave Shape
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
Thread Tools Search this Thread
Old 14th May 2008, 02:25 PM   #1
N-Well is offline N-Well  France
diyAudio Member
Join Date: Feb 2006
Location: Z french Alpes
Default Aleph 30 - 1nF cap and Square Wave Shape


I've juste built an Aleph 30. It sounds great. I use it in an active system, below 300Hz.

There is only one thing I noticed on square wave at 10kHz on 8ohm+1.5F load: there are oscillations superposed , without the 1.5F, no oscillations but a slight overshoot on the rising steep.

So I have one question about the 1 nF cap. that is on the original Aleph 30 schematic between the output and the drain
of the left mosfet of the differential 9610 pair.
I've use BrianGT boards and this caps is not present at all.

What's its purpose and is it that critical ?

Have you experienced similar oscillo Traces with this cap as well N ?

  Reply With Quote
Old 15th May 2008, 01:47 AM   #2
MEGA_amp is offline MEGA_amp
diyAudio Member
MEGA_amp's Avatar
Join Date: Oct 2003
The only 1nF I see on the Aleph 30 circuit is C7 which is in the Aleph current source. The other 1nF thats in some Alephs is to prevent oscillations due to longer traces in the commercial board. This is not necessary with BrianGT's boards as it is fairly compact.

This pic is from an Aleph 2, the Aleph 30 schematic does not have it:
Attached Images
File Type: jpg untitled.jpg (16.7 KB, 290 views)
  Reply With Quote


Aleph 30 - 1nF cap and Square Wave ShapeHide 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
Sine wave - Square & Triangle wave generator using Transistors / OP-Amps lineup Solid State 20 9th October 2006 12:15 AM
Microphone turns triangle wave into square wave? Circlotron Analogue Source 18 25th January 2003 06:44 AM

New To Site? Need Help?

All times are GMT. The time now is 10:49 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio