Pass Aleph L 1.2?Maybe O.T. - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

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
Reply
 
Thread Tools Search this Thread
Old 30th January 2009, 04:40 PM   #1
diyAudio Member
 
Join Date: Jan 2009
Default Pass Aleph L 1.2?Maybe O.T.

I want to buy a second hand aleph L but the seller don't know the version.
The serial number is 07544.
Is the 1.0 version or 1.2?
Thank you very much
  Reply With Quote
Old 30th January 2009, 08:39 PM   #2
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
Harrington has already answered this question via email, but for
general information, the later one has 2 white wires from the
volume control to the board, for a total of 8 eight wires.

  Reply With Quote
Old 31st January 2009, 02:02 PM   #3
diyAudio Member
 
Join Date: Jan 2009
Thank you Mr.Pass
  Reply With Quote
Old 11th March 2009, 11:20 PM   #4
diyAudio Member
 
Join Date: Nov 2008
Default Re: Pass Aleph L 1.2?Maybe O.T.

Quote:
Originally posted by michelangelo
I want to buy a second hand aleph L but the seller don't know the version.
The serial number is 07544.
Is the 1.0 version or 1.2?
Thank you very much

Hi Michelangelo, did you get an answer to your question, I'm considering buying a used Aleph L as well, serial number 7128, pretty close to what you mentionned, what was 7544?

Thanks!
  Reply With Quote
Old 23rd March 2009, 12:40 PM   #5
Heiney9 is offline Heiney9  United States
diyAudio Member
 
Join Date: Apr 2005
Location: MidWest
Need a little clarification about a used Aleph L as to which version the seller has.

Serial #07598

I had the seller open the top to check the wiring and this was his response:

Okay, I just carefully took the top off; mine has 6 wires from the volume control to the board. Two white, two red, two blue.

Before I buy I'd like to be absolutely sure about which version he has. He thought because the prior owner mentioned the fact that until the 3:00 position it was in passive and then switched to active (which would indicate it's a the later version 1.2). But he's not sure what version he has either and I'm not sure the prior owner even knew there are 2 versions. He could have just been repeating what he read in the on-line owners manual.

Thanks so much for any input to help determine if this is a 1.0 or 1.2. I'm anxious to mate it to my Aleph 30 amp.
  Reply With Quote
Old 23rd March 2009, 07:39 PM   #6
Heiney9 is offline Heiney9  United States
diyAudio Member
 
Join Date: Apr 2005
Location: MidWest
The seller of the Aleph L talked with Desmond as Pass Labs and confirmed the one I an looking at is in fact the earlier 1.0.

It's my understanding that there is a series of dip switches inside the unit by which you can change the gain from the factory set 6.5dB to either 3.4dB or 0dB.

So the next obvious question, is this considered a purely passive pre-amp regardless of the gain setting? Or is it strictly passive at the 0dB gain setting and considered active for the other (2) settings.

I've read the 1.0 is a purely Mosfet design which is active.

Thanks for clearing up some of the questions for me.

H9
  Reply With Quote
Old 23rd March 2009, 08:44 PM   #7
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
It is a unique circuit in that at a midpoint setting of the volume control
it is a pass-through from input to output, below that it is a passive
attenuator, and above that it taps into the output of a gain stage.

  Reply With Quote
Old 23rd March 2009, 09:33 PM   #8
Heiney9 is offline Heiney9  United States
diyAudio Member
 
Join Date: Apr 2005
Location: MidWest
Thanks for the response, I appreciate it very much. I assume since the "L" was designed around the same time the Aleph 3 was that they "play" well together and would do the same with my current Aleph 30 as well?

Perhaps you could shed a little light on what difference in sound one might notice/expect between the Aleph L and the Adcom GFP750 which I am currently using with my Aleph 30. This combo sounds fantastic and I'm not wanting to loose the great synergy.

How important is the fact the GFP 750 is balanced vs. the single ended inputs/outputs of the Aleph "L".

Looking forward to your repsonse.

Brock
  Reply With Quote
Old 23rd March 2009, 09:54 PM   #9
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
Quote:
Originally posted by Heiney9
How important is the fact the GFP 750 is balanced vs. the single ended inputs/outputs of the Aleph "L".
The bulk of audiophiles seem to prefer the balanced topology with
its cancelled 2nd harmonic.

  Reply With Quote
Old 24th March 2009, 02:58 PM   #10
Heiney9 is offline Heiney9  United States
diyAudio Member
 
Join Date: Apr 2005
Location: MidWest
Quote:
Originally posted by Nelson Pass


The bulk of audiophiles seem to prefer the balanced topology with
its cancelled 2nd harmonic.

Perhaps you could expound a little bit on why/how the 2nd harmonic is cancelled? Is this the only way to cancell a 2nd harmonic?

I'm intrigued but admit I don't quite understand it all.

Thanks again

Brock
  Reply With Quote

Reply


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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pass Aleph 0s GRollins Pass Labs 1 2nd February 2010 07:57 PM
Thanks Mr Pass for my Aleph 2 and UGS diy Lau700 Pass Labs 19 1st August 2007 07:51 PM
Pass 350.5 vs aleph daly41k Pass Labs 8 19th March 2007 03:19 PM
Pass Tharagard A75 vs Pass Aleph 1.2's daly41k Pass Labs 7 18th February 2007 03:10 PM
pass aleph P VS pass X2 first version perusicchio Pass Labs 10 5th March 2004 10:06 AM


New To Site? Need Help?

All times are GMT. The time now is 10:46 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2