distortion analyzer recomendations? - Page 19 - 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 29th November 2007, 04:17 AM   #181
1audio is offline 1audio  United States
diyAudio Member
 
Join Date: Mar 2004
Location: SF Bay Area
Blog Entries: 3
I think $300 for a 334 is high. You should be able to get a self tuning auto ranging unit for that- like a Tek or a KH or a ST 1700 with a generator included for that price. Unless you are collecting for collecting's sake these are just tools and you want the most tool for your money. Or a good soundcard (juli@) and software. I used RMAA to test FM transmitters which worked really well.
__________________
Demian Martin
Product Design Services
  Reply With Quote
Old 29th November 2007, 02:18 PM   #182
glen65 is online now glen65  United States
diyAudio Member
 
Join Date: Jun 2004
Location: Richland County Ohio
Iíve been spending some time reading
the posts here as it pertains to the analyzer software.
Please correct me if Iím wrong but the ďoverallĒ impression
I get is that itís not really a full blown replacement for a good analog distortion analyzer. This is because of sound card being the weak link of the setup because of its limited input capabilities unless of course you have a buffer between the signal source and the input. I seen someone here suggest that you can take the output of an analog distortion analyzer and run it into the input of the sound card essentially using the distortion analyzer itself as the buffer rather than building one using a resistance network or op amp. Have you or others actually tried or seen this done?

Thanks
  Reply With Quote
Old 29th November 2007, 04:47 PM   #183
1audio is offline 1audio  United States
diyAudio Member
 
Join Date: Mar 2004
Location: SF Bay Area
Blog Entries: 3
It all depoends on what you are doing with it. The input overload limits what you can connect to the soundcard so an input conditioner is necessary to prevent overload and scale for optimum dynamic range.

I have used a soundcard with a distortion analyzer and it works, but not for my regular use. I have a self contained FFT analyzer (Wavetek 7530A) connected to the output of my analyzer. (Boonton 1120). But your needs may well be different.
__________________
Demian Martin
Product Design Services
  Reply With Quote
Old 29th November 2007, 05:18 PM   #184
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Look around for an HP339, sometimes these show up for not a whole lot more money than the 334 you mention and it is a much nicer, and more modern instrument.

I have an old Amber 3501A - this is quite a nice instrument as well, provided you buy one in good working order or can fix it. I recently overhauled mine and it is working almost as good as when new. Amber is long out of business, but there is a small but growing cadre of enthusiasts who work on these and share information.

One of the better M-audio 24 bit pci cards or EMU 24 bit cards would make a good choice for use with audiotester or arta software and are very capable.

Front end conditioning is a must with a sound card, but with a little thought in design you can get extremely good results using this approach. Personally I think this is far more useful than most simple thd analyzers. (In fact I used mine to check the old Amber as I was repairing it.)

The ultimate of course would be a 2700 series Audio Precision, but even the older System Ones are awesome. (I'd love to own one - way beyond my budget though.)
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 3rd December 2007, 05:32 AM   #185
1audio is offline 1audio  United States
diyAudio Member
 
Join Date: Mar 2004
Location: SF Bay Area
Blog Entries: 3
Default Boonton analyzer resource

Software for the Boonton 1120/1121 Analyzer can be had here:GPIB
And I posted layouts and instructions for filter boards for them here:

PCB Schematic Assembly list

The layout is in expresspcb format (. The boards are $51 for three in 3 days.Free download ).
__________________
Demian Martin
Product Design Services
  Reply With Quote
Old 3rd December 2007, 03:24 PM   #186
glen65 is online now glen65  United States
diyAudio Member
 
Join Date: Jun 2004
Location: Richland County Ohio
Thank you for the links,
The one for the assembly list doesnít appear to be working.
Can it be had someplace else?
  Reply With Quote
Old 3rd December 2007, 03:33 PM   #187
Pars is offline Pars  United States
diyAudio Member
 
Pars's Avatar
 
Join Date: Jan 2004
Location: Chicago
I've been using an M-Audio Firewire Audiophile external box with RMAA for a bit now. I'm curious as to what kind of protection or conditioning needs to be done on the input? So far I haven't had any problems with it, but I don't want to damage the inputs. Any suggested schematics, etc. for this?

I've used it both for amplifier (i.e., preamp or headphone amp) distortion measurements as well as used it to set the biasing (distortion measurements) on my counterpoint preamp (a little slow, but it worked).

Thanks,

Chris
  Reply With Quote
Old 3rd December 2007, 04:12 PM   #188
1audio is offline 1audio  United States
diyAudio Member
 
Join Date: Mar 2004
Location: SF Bay Area
Blog Entries: 3
Quote:
Originally posted by glen65
Thank you for the links,
The one for the assembly list doesnít appear to be working.
Can it be had someplace else?
Dumb syntax problem. Here is the correct link


Assembly List
__________________
Demian Martin
Product Design Services
  Reply With Quote
Old 3rd December 2007, 07:08 PM   #189
diyAudio Member
 
redrabbit's Avatar
 
Join Date: Oct 2004
Default Spectrum

Quote:
(1audio wrote...) I think they (HP 3581a) are fine but not a replacement for an audio analyzer. Hang it on the output of the analyzer.
Hang it on the output of the analyzer....will tell me what ?

I am reviewing the 3581a manual....forgive my novice-ness....to "get" or "see" results from this unit (plot/graph), a digital storage scope or XY plotter is needed too ? I only have an analog scope.
-----------

I've been buying stuff lately (so I have a lot of manual reading to do)... these:

HP 3581a ($20)
Spectral Dynamics SD345 II ($600)
Spectral Dynamics SD375 II ($100)
Hrohn-Hite 3800 tracking filter ($100)

http://i5.photobucket.com/albums/y17...t/DSCN2695.jpg

I think I paid too much for the $600 spectrum analyzer, because I just got it's bigger brother (SD375) for $100.....go figure ??


------------------
Quote:
(Anatech wrote earlier...) What I need to do is play with a number of these signal analyzers (spectrum analyzers) to see what I like the best.
The SD3xx above looks like a good budget Ebay find....they pop up now and then. I made sure the buyer would guarantee it would not be DOA, serviceability might be difficult. Mine work great so far.

http://www.cognitivevision.com/legacy.htm

Click the image to open in full size.

=RR=
  Reply With Quote
Old 3rd December 2007, 07:57 PM   #190
1audio is offline 1audio  United States
diyAudio Member
 
Join Date: Mar 2004
Location: SF Bay Area
Blog Entries: 3
The audio analyzer removes the fundamental so you don't need the dynamic range and then the other stuff is easy to see.

Those FFT's have a substantial learning curve. They can do a lot but the controls are not simple. Do they have GPIB on them? They also are limited by the A to D stage which by modern sound card standards is pretty obsolete.
__________________
Demian Martin
Product Design Services
  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
Distortion Analyzer - Again Zero Cool Equipment & Tools 4 30th June 2013 12:14 AM
Distortion analyzer recommandations? tschrama Equipment & Tools 3 10th June 2008 08:47 AM
distortion pedal recomendations please facundonu Instruments and Amps 8 20th September 2006 03:50 AM


New To Site? Need Help?

All times are GMT. The time now is 08:19 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