Audio Precision ATS-1 Access

[emrr]

I'm just starting to become acquainted with this piece of test equipment.  Any power users here?

Wondering what the current best printer / capture solution is.  It has a female DB-25 parallel printer port and can follow Epson/IBM dot-matrix/ink jet standard or PCL ink jet/laser jet standard.  It also has IEEE-488 (GPIB) interface for control.  I haven't even sorted whether that allows for data capture via host computer, or not. 

Is it worth having the IMD option added?  It's not cheap, nor is anything related to Audio Precision.  This unit has BNC and banana jack connections, and after looking into the XLR panel cost I will probably just make some XLR pigtails.

How do you feel about calibration, given the unit passes the self test?  I understand there are some batteries that help store some cal settings, and service may be required at that time. 

 

[Gold]

I have a Portable One but am anything but a power user. AP tech support has a list of suitable currently available printers.

 

[edanderson]

there are solutions to capture data via gpib, but none of them are cheap or very easy to use (either roll your own software or matlab, plus a $500 gpib card).  AFAIK the printer port is only good for printing, though you could print and scan.

i would rather spend $2000-$3000 on an old system one where you can save the data more easily.  i bought a refurbished one recently for $2500 with a warranty from a local test gear place.

ed

 

[MicDaddy]

i would rather spend $2000-$3000 on an old system one where you can save the data more easily

ditto that, a system 1 or 2 I find to be very friendly with printing/sharing saving/recall.

I've only briefly played with a portable and none at all with the ATS-1  (I had to google for a photo of the model) 

Are you using the ATS-1 in some variety of standalone operation, or is it paired with a pc?

 

[emrr]

Just acquired it from a friend, it was likely on the way to the dumpster where he works!

Portable One is the same thing, different package. 

Might have to make do with printing and scanning data.  No PC paired with.  I'm entirely in Mac world too.  I noticed some GPIB/USB adapters  in the $150 range.  I had a look at the programmers manual, and yes, it looks like a big learning curve and a lot of manual data entry to get set up. 

 

[jsteiger]

Just acquired it from a friend, it was likely on the way to the dumpster where he works!

Portable One is the same thing, different package. 

Might have to make do with printing and scanning data.  No PC paired with.  I'm entirely in Mac world too.  I noticed some GPIB/USB adapters  in the $150 range.  I had a look at the programmers manual, and yes, it looks like a big learning curve and a lot of manual data entry to get set up.

Doug, I just plug an older HP 1200 laser jet into the parallel port when I want to print some sweeps. It is a PIA to scan but the printing has been fine for me. I really only do it occasionally. Also only B&W (from what I know). You just need to select the printer format in the 4th "panel" which is Setup. I always print the freq table for easy, detailed comparison. I would like to move up one day but it's not anytime in the near future so I just work with what I have. FWIW, I really love the unit and could hardly work without it. I have a number of typical tests stored that I use frequently. It is super easy to navigate around. The Gen Load is a nice feature that not all AP's have AFAIK. A quick press will show the DUT's input Z if it is under 20k. Nice for mic preamps.

I have the PDF manual if you can't still find it on AP's site.

I wish it went below 10Hz but I guess we shall struggle thru. 

Best, Jeff

 

[edanderson]

problem with the sparkfun and similar ~$150 USB to GPIB interfaces is that they are not supported directly by matlab (there is an AP panel file for matlab you can download from AP).  so you'll have to pretty much roll your own software if you want to use the cheap interface.  on the other hand, the matlab compatible interfaces are more like $500 and a copy of the software is several thousand, so that's not a cheap option either.

nothing wrong with the measurement quality of the ATS-1 (slightly lower bandwidth than a system one/two but still plenty), and certainly glad you rescued it from the dumpster!

ed

 

[[silent:arts]]

Take it, use it as it is.
Works for 95% you need / want.
I have a Neutrik A2 & an AP portable one on my bench at work.
Most times using the A2, the AP portable one for impedance or if I need a 2nd or backup or to verify.
(since I´m more used to the A2 it is preferred by me).

I have access to AP System 1 / AP System 2 and even the latest models, but if you don't need / use them every day they are too complicated to use.

Everything working without a computer connected is easier to handle most times ;D

 

[emrr]

Cool, thanks guys.

Sounds like GPIB is likely beyond me needs or means.  If I have to scan printouts, so be it. 

I'm noting the Gen Load test isn't necessarily to be trusted with reactive loads, so testing many mic preamps for input Z is out.  The manual says as much.  I can change the signal level at one freq and watch the result change.    Haven't devoted brain cells to sorting if there's another step that would give meaningful results, maybe in combo with inductance readings? 

Better than 10 Hz would be nice, I have SpectraFoo Complete also, so it will be interesting to compare freq sweep results.  There are a number of things I don't completely trust with Foo, so I can now confirm or deny.  Maybe. 

 

[jsteiger]

....I'm noting the Gen Load test isn't necessarily to be trusted with reactive loads, so testing many mic preamps for input Z is out.  The manual says as much....

Sure enough. I didn't remember reading that before. I had to go back and look. It's kinda lightly tossed in at the end of that section. Bastards.

 

[emrr]

Set up Gen Load on a transformer preamp, get a reading, then bump generator output up and down 10 dB, watch the reading change.  Sometimes drastically. 

 

[jsteiger]

Doug

I am working on some things today and figured I would further experiment with a VP312 and the Gen Load function for fun. Typical 312 style preamp with one of Ed's 2622's on the input, no pad engaged and no 150k loading R installed after the zobel. The AP was set with a 150R source Z. My normal sweep is stored with a -43dBu level at the input. At 1k, I get a very constant 1.27k impedance reading from off to around +5dBu, which is where I start clipping the input. I went in 10dB steps with 1.26k and 1.28k popping up one time each. Now, once it started clipping, the Z would naturally start dropping. Also, if I increase the gain and start clipping the 2520, the Z would drop, as to be expected. Otherwise, very consistent.

Now that is at 1k. Other frequencies are different mostly as I approach 20Hz and 20kHz. Again, to be expected. Funny enough, a lot of manufactures just list the input impedance with no reference frequency noted. I guess we are to assume it's at 1k. Anyhow, I am pretty secure with what I just found on this API style preamp. I am pretty sure you will have many different preamps that may be much more reactive. Good homework none the less.

Cheers, Jeff

 

[emrr]

Thanks Jeff.  I'll report more when I'm back in testing mode. I've seen very different results with some pre-1970 gear so far.