Go Back   Home > Forums > Source & Line > Analogue Source

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, etc.

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 5th December 2012, 07:20 PM   #7921
RCruz is offline RCruz  Switzerland
diyAudio Member
 
RCruz's Avatar
 
Join Date: Sep 2006
Location: Wallis
Blog Entries: 1
Full schematic please.... I am getting to understand these things after all !
__________________
RC
  Reply With Quote
Old 5th December 2012, 07:32 PM   #7922
diyAudio Member
 
Stefanoo's Avatar
 
Join Date: Apr 2006
Location: italia - ora USA -WI
Quote:
Originally Posted by RCruz View Post
Full schematic please.... I am getting to understand these things after all !
here you are.
It is a pretty neat circuit unfortunately we don't reach a 0.7-0.5nV noise figure
Attached Images
File Type: jpg oneshot.JPG (152.4 KB, 165 views)
__________________
Stefano
  Reply With Quote
Old 5th December 2012, 08:31 PM   #7923
MiiB is offline MiiB  Denmark
diyAudio Member
 
Join Date: May 2005
Location: Denmark
Oh.... That's my circuit... a few years OlD....Something needs to change, The folding of the second stage is quite unique.. There is some novelty in that... I have had a line-stage built this way. The dissipation in the mirrors can be an issue and the transistors may need to be heat-sinked.
  Reply With Quote
Old 5th December 2012, 08:36 PM   #7924
diyAudio Member
 
Stefanoo's Avatar
 
Join Date: Apr 2006
Location: italia - ora USA -WI
the heatsink is the least of the problems here

Check noise!
Beside RIAA is kind of bazar, but that might come later.

Let me know if you have any suggestion as to improve noise.
For a line stage it could be ok, gain drops down significantly and so does noise.
However when it comes to high gain you can really tell how good the circuit design is with respect to noise performance!
__________________
Stefano
  Reply With Quote
Old 5th December 2012, 09:01 PM   #7925
diyAudio Member
 
Joachim Gerhard's Avatar
 
Join Date: Mar 2009
A differential stage always has a noise penalty of 6dB, anyway, it is a very good and novel circuit that deserves more attention
  Reply With Quote
Old 5th December 2012, 09:10 PM   #7926
diyAudio Member
 
Stefanoo's Avatar
 
Join Date: Apr 2006
Location: italia - ora USA -WI
Quote:
Originally Posted by Joachim Gerhard View Post
A differential stage always has a noise penalty of 6dB, anyway, it is a very good and novel circuit that deserves more attention
ok but then even phono stage like the boulder should have a noise figure of that leverl since they are FULLY balanced, while the noise figure is extremely low!

I think that this circuit is pretty novel, but hard to fit a current RIAA.
However the one stage circuit here is pretty neat too...I am try to work it out trying to get the necessary gain out of it.
If I can then I can try to build it too.
__________________
Stefano
  Reply With Quote
Old 5th December 2012, 10:07 PM   #7927
diyAudio Member
 
Joachim Gerhard's Avatar
 
Join Date: Mar 2009
Stefano, this is simply not true. Atkinson says it is " superb " but 60dB unweighted ( ref.
0.5mV ) and 64.75dB A weighted is a joke. The Paradise is around 12dB better.
We are setting standards here, this is not a joke but hard work.
Attached Images
File Type: png Boulder S:N.png (34.4 KB, 154 views)

Last edited by Joachim Gerhard; 5th December 2012 at 10:35 PM.
  Reply With Quote
Old 5th December 2012, 11:04 PM   #7928
diyAudio Member
 
Stefanoo's Avatar
 
Join Date: Apr 2006
Location: italia - ora USA -WI
I picked the wrong one.
Try with esoteric phono...even the cheap trigon is dead quite and list goes on and on.
Paradise is very good noise wise but there is more than the noise on the equation of good sound though for cutting edge sound.
However I would be interested in knowing what the average noise floor that can be considered acceptable is.
Like a said our goal (or maybe just mine don know) is to build a phono that not only sets a Standard noise wise… But also sound wise!
__________________
Stefano
  Reply With Quote
Old 5th December 2012, 11:26 PM   #7929
brianco is offline brianco  Ireland
diyAudio Member
 
brianco's Avatar
 
Join Date: Aug 2005
Location: Scottish Borders - Kelso; on the famous Tweed River!
@ Stefanoo

What we all seem to forget is that there is more to amplification design [and to both 'design and matching' of all other parts of the sound system] than instrument read or simulation predicted analysis or data can tell us. Sure, a truly 'good' amplifier will measure pretty well......but there is more to it than that - there are many many amps which measure well but fail in the listening.

I believe that there is a point where 'best' audio design, which is a scientific/EE pursuit - if all we want is impressive mute lab results - begins to merge [or morph] into artistic creation.

Whilst simulation can be of great help in balancing the many design factors, it can never, of itself, straighten out a design from an aural perspective. We also know that very many of the available device models are not adequately accurate for work at this level. That being so simulation, though useful in part, cannot be used as an arbiter in "fine" design. Only ears can make such choices.
  Reply With Quote
Old 6th December 2012, 12:00 AM   #7930
diyAudio Member
 
Joachim Gerhard's Avatar
 
Join Date: Mar 2009
Stefano, the phono stages from the German Trigon ?
That has an AD797 in the input so has John Curls phono stage for Parasound and the Linn Urika among others.
Now we are talking about 1nV/ QHz that is ok but that does not impress me.
I can design stages like that in 10 minutes.
How do you design for great sound ?
A stage that buries micro details in noise is not on my agenda.
  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



New To Site? Need Help?

All times are GMT. The time now is 04:37 AM.


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