Audio Precision System One woes - diyAudio
Go Back   Home > Forums > Design & Build > Equipment & Tools

Equipment & Tools From test equipment to hand tools

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 20th March 2012, 11:09 PM   #1
diyAudio Member
 
Loudthud's Avatar
 
Join Date: Nov 2007
Location: Near Dallas Texas USA
Default Audio Precision System One woes

I got an old Audio Precision System One off ebay. Probably the lowest model, it only has one analog channel, a serial port, and the AP bus. I found out only the oldest version of software (that runs under DOS) supported the serial port. The last release of software that can be used runs under Windows 98. There are some former AP employees selling little lunchbox computers on ebay with a driver that will allows the printer port to be hooked to the AP bus with a special cable. So now I can talk to the box and it seems to work. Figuring out the software without any documentation is a pain but, I'm slowly getting up to speed.

One thing I would like to do is create those nice graphs like Nelson Pass does of distortion vs output power for a power amp. The only options I can find for the horizontal axis is oscillator output, either voltage or power (mW). I suppose I could use an attenuator on the oscillator so that 1mW of oscillator power equals 1W of output power or something to that effect. I really don't want to have to dig into their scripting language.

Do newer AP systems create these graphs without all the hassle?
  Reply With Quote
Old 24th March 2012, 06:21 AM   #2
diyAudio Member
 
Loudthud's Avatar
 
Join Date: Nov 2007
Location: Near Dallas Texas USA
Default Success !!!

Well, I finally did it! That thing is complicated. Shoulda joined that company when I had the chance.
Attached Images
File Type: gif First_graph.GIF (12.7 KB, 424 views)
File Type: gif THD_vs_Watts_Setup.GIF (34.4 KB, 417 views)
  Reply With Quote
Old 24th March 2012, 07:58 AM   #3
Enzo is offline Enzo  United States
diyAudio Member
 
Join Date: Sep 2004
Location: Lansing, Michigan
Well cool.

As long as it got you where you wanted to be.
  Reply With Quote
Old 24th March 2012, 09:40 AM   #4
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Hint: If you register at AP.com (free), and go to the 'Legacy' page (do a search) you can download all kinds of documentation, app notes, user guides and even service manual.
Then there's the vintage AP user group at LinkedIn, with lots of friendly people including ex-AP engineers.
Didn't think about that, ha!

jan didden
__________________
I won't make the tactical error to try to dislodge with rational arguments a conviction that is beyond reason - Daniel Dennett
Check out Linear Audio Vol 7!
  Reply With Quote
Old 24th March 2012, 10:52 PM   #5
diyAudio Member
 
Loudthud's Avatar
 
Join Date: Nov 2007
Location: Near Dallas Texas USA
I'm registered on the AP site. Sifting through many megabites of info takes a lot of time and I'm not going to print out a 300+ page manual. Went through many of the ap notes, didn't find anything about plotting power as the horizontal axis. The original System One operators guide uses the DOS version of the control program (S1.exe), it's a little different. There's a book by Metzler that explains all the different units used in measuring audio. Very usefull.

Two things were holding me back. One, you have to double click on the sweep menu to get the "large version" to display. That's where the X-Y button is located. Second, because my box only has one channel, I thought "Data 2" referred to the second channel. I haven't seen anywhere in any manual where it talks about a single channel analyzer. I just had to sit down and play with the box to see how it works and try to learn from the help files.

Now I need to get proper test leads together and clean up the amp I'm building so there are not so many clip leads. Get rid of those wavy lines around the 1 watt level.
  Reply With Quote
Old 24th March 2012, 11:00 PM   #6
diyAudio Member
 
Join Date: Jun 2009
Send a message via Yahoo to kannan_s
Can you post the picture of your AP Sys 1 - also hint on the price you paid for this piece?
thanks
kannan
  Reply With Quote
Old 25th March 2012, 05:01 AM   #7
diyAudio Member
 
Loudthud's Avatar
 
Join Date: Nov 2007
Location: Near Dallas Texas USA
I had forgotten what I paid, so I looked it up. The price seemed high, (it was a few years ago). Then I looked on ebay to see what's on there now. It was less than any of the AP boxes (not including switchers) on ebay (USA) right now. I had no idea you could spend $20K to get the latest and greatest. I have a Tektronix distortion analyzer and low distortion oscillator. They are from the 80's, designed by the same guys that started AP. The AP box just makes it easy to plot those graphs and store them. I'm not into the ultra low distortion, but it's nice to look at the analyzer output to see the harmonics. I guess the next step would be some way to do FFTs.
Attached Images
File Type: jpg MVC-091F.JPG (68.0 KB, 369 views)
  Reply With Quote
Old 27th May 2013, 04:51 AM   #8
The Dastardly Dad of Three
diyAudio Member
 
Join Date: Sep 2009
sorry to wake this thread up again ... but did anyone find a decent solution to connect one of the older APs to a PC without a GPIB bus ? I have a Portable 1 and right now i'm logging readings into an excel and drawing charts which is an amazing pain. I went out and bought a aprallel port laser printer (not too easy to find these days) and plugged in but i get gibberish out regardless of what emulation I select on the printer and /or on the AP. I researched it and theres someone that sells a generic solution for parallel port to data solution but no word on whether anyone has tested and found that it works on an AP.... Loudthud, in your first post you mentioned "There are some former AP employees selling little lunchbox computers on ebay with a driver that will allows the printer port to be hooked to the AP bus with a special cable. So now I can talk to the box and it seems to work. Figuring out the software without any documentation is a pain but, I'm slowly getting up to speed." ... would this work for me you reckon ? thanks!
  Reply With Quote
Old 27th May 2013, 06:36 AM   #9
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Again, these same issues are discussed on the LinkedIn classic AP group. There are several ex-AP engineers and one guy sells AP adapters or miniPC's. Your best bet.

jan
__________________
I won't make the tactical error to try to dislodge with rational arguments a conviction that is beyond reason - Daniel Dennett
Check out Linear Audio Vol 7!
  Reply With Quote
Old 27th May 2013, 10:00 AM   #10
The Dastardly Dad of Three
diyAudio Member
 
Join Date: Sep 2009
Thanks jan - am not familiar with the linkedin group but this is a great reason to find out
  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
Audio Precision System 1 mickeymoose Swap Meet 4 23rd April 2010 06:47 PM
Audio Precision System One 11G Michael Rothacher Swap Meet 7 19th April 2010 12:53 PM
Audio Precision System One for sale alaskanaudio Swap Meet 3 3rd November 2008 07:22 AM
Audio Precision System 1 users? jan.didden Class D 12 28th December 2006 07:15 PM
Audio Precision System One for sale marcreviel Swap Meet 0 2nd December 2002 05:18 AM


New To Site? Need Help?

All times are GMT. The time now is 09:58 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