Test & Measurement Equipment for DIY Designers

Can anyone share what some of the most popular choices are for test and measurement equipment for high performance amplifier design work?

Beyond your basic precision Meters, Scope, Bench Power Supply, etc., what tools are really required to design and evaluate the worlds best designs?

How far can one go with free downloadable software like Right Mark Audio Analyzer and high-end Professional Audio Workstation sounds card? So far, RMAA and an M-Audio Delta 66 has been pretty helpful to me. What does it take to get to the next level?

Budget is hundreds to thousands, but not tens of thousands...
 
There is Audio-Tester (www.audiotester.de)

after that is Spectra Plus with a Lynx L22 card. A pretty big ticket item but a tiny fraction of the cost of an AP system.

Both of these have the issue that you need to feed the signal back in to the soundcard. For that you need to build your own voltage divider and isolation buffer. The idea of feeding amplifier output in to an expensive but unprotected soundcard should make one pause and reflect before jumping right end.

One way to avoid that is to use an external module such as Picotech's 16 bit unit or the Velleman unit.
 
I use:

-HP 204D sine / square generator, THD 0.1%

-HP400GL rms AC-voltmeter, measures down to 10uV rms

-DIY 1KHz pure sine generator, THD < 0.0005% (NE5534 wienbridge)

-DIY Distortion Analyzer (www.sound.au.com Project 52 & 59, NE5532), measures THD down to 0.0005%

20MHz osciloscope (about 500$), 2 channel, build in sine-generator

PC with soundcard for spectrographic analysis

I also used to have a scientific grade , calibrated, National Instruments 200samples/sec 16bit DAQ card controlled with Labview software, which was excelent for audio testings.. one day it died on me...:bawling:


PS
allmost forgot... goldwave audio software, nero CD burning software and a CDplayer for a cheap and simple pure sine generator
 
Hi all,
A good low cost generator @ band 1hz-100khz and low audio band thd= 0.002% is the Black Star LDO100 ( I use it with an ADC216 Picotech as FFT analizer ).
The quality of the recent PCaudio card ( and of the new software ) allows to get very accurate measures, but is fundamental an analogical interface in degree to isolate the loop GNDS and to adapt the input/output signal levels. the programs indicated by sam9 are interesting and they prepare of all the tools of analysis. In particular, the generators of signals are able to reproduce nonelementary forms a lot of difficulties to produce ( with low THD) with standards generators. If some were in degree to signal a good interface circuit for PC card to high performances ( and with isolation of GND ) I am very thankful...

Ciao

Mauro
 
tschrama said:

I also used to have a scientific grade , calibrated, National Instruments 200samples/sec 16bit DAQ card controlled with Labview software, which was excelent for audio testings.. one day it died on me...

the NATI cards show up on EBay very frequently -- I have one which was purchased for about 1/4 the cost of new.

in addition to all the above "honorable mentions" you should consider getting a decent power supply with which to test out your projects. it can be as simple as a Lambda or Acopian "opamp" supply with +/- 15V, or a more versatile tracking supply.

also -- Textronix TM500 and TM5000 test equipment bays are really excellent -- I use one with a PS5010 programmable power supply , a couple of auto-ranging DMM's, pulse generator and an SG505 signal generator. there is a guy in Canada selling vector-style circuit cards for the TM500 series so you could build your own IMD or THD analyzer, tone burst generator etc. I am very enthusiastic about the TM500's because they are inexpensive and very high quality.
 
What about the new Terratec Phase-X-24 (Firewire 24bit 192kHz) with Rigthmark Audio Analyzer?

For audio testing that would be a serieus waste of money...:whazzat: 350 euro... .. you can get 108dB S/N for a 45 Euro Creative Audigy 2 ZS .. yes it's 24 bit .. audigy 4 pro gives 113dB they say... not that you would need any of that.. . most onboard snd-cards are sufficient if you wanna go that road ... just build yourself a bit of signal conditional hardware.. it's DIY here you know?


350 Euro!! ...:whazzat:...:whazzat:...:whazzat: you can get some serious equipment for that from National Instruments..
 

EDUM

Member
2003-10-02 9:21 am
Almere
a serieus waste of money...

The Creative products (2ZS and 4Pro) do not have a 192 kHz recording capability... The Phase-X-24 does. If you want 192kHz AD converters the price range becomes a bit different. Depending on the quality you want to have this 350 Euro is not that bad. A Lynx card is much more expensive.

If you look at the National Instruments products you will find out that only one product (last time i checked) the PXI-4461 has a similar 24 bit and 200kHz AD/DA spec. If you also want the sound and vibration SW with it, the price tag goes upto 10k Euro. Not exactly DIY prices anymore.

If you want something DIY-ed I am afraid that building something with 100 dB S/N is (unfortunately) not easily done.

The big question of course is how much you need. I believe that measurement equipment should be a league better than the things you measure. Of course you can choose lesser specs as long as your measurement results are treated with that in mind.
What you want to spend is the other question. If 350 Euro for a Phase-x-24 is to much, you can settle for a phase 24 (it's predecessor) which should come for a 200 Euro.

Cheers!

Ward:
 
EDUM said:

If you look at the National Instruments products you will find out that only one product (last time i checked) the PXI-4461 has a similar 24 bit and 200kHz AD/DA spec. If you also want the sound and vibration SW with it, the price tag goes upto 10k Euro. Not exactly DIY prices anymore.

If you want something DIY-ed I am afraid that building something with 100 dB S/N is (unfortunately) not easily done.
Ward:

http://www.ni.com/pdf/products/us/pxi4461.pdf -- $3,995 for US Delivery.

Reading low levels, i.e. RMS in the nanovolts, is difficult but certainly not impossible. A thermal measurement setup is best -- like an amplified HP3403C. Forget about using RG58 from Radio Shack, however.

For sourcing, you can do 120dB and better as DIY, but again it is by no means easy -- Cyril Bateman showed how to make a 1kHz signal source with better than -120dB in his capacitor article in Eelctronics World -- used an SSM2018 VGA amplifer from ADI -- Linear Tech also has an article by Eagar on an "UltraPure" oscillator and I know at least one DIYAUDIO member has built it.

Linear Tech also has a very good series of articles in Application Notes 67 and 61. Must read if you are into looking at nanovolts.

Bob Pease from National Semiconcductor also has a couple of very instructive articles, one which I have in my files is "What's all this femto-ampere stuff anyway?". National keeps his articles archived.
 
The Creative products (2ZS and 4Pro) do not have a 192 kHz recording capability... The Phase-X-24 does.

Nope it does not...
# 24-bit / 192-kHz analog signal processing :smash: :smash: :smash:
# 24-bit / 96-kHz digital signal processing
mmwwooeehahahaa ... funny guys at terratec.

If you look at the National Instruments products you will find out that only one product (last time i checked) the PXI-4461 has a similar 24 bit and 200kHz AD/DA spec. If you also want the sound and vibration SW with it, the price tag goes upto 10k Euro. Not exactly DIY prices anymore.

My NI PCI6013 costs me about 105 Euro at ebay.. it has 16 input channels or 8 balanced, it has 250KHz sampling rate .. Yep that;s right, the 200KHz they spec, is conservatively rated! and those 16bit are REAL 16bit.. those 16 bit resolution profided me more S/N any soundcard I have, including audigy zs2 24bit creative cards.. and you do NOT need the sound&vibration toolbox for an FFT in labview! use the demo software and you WILL be cheaper off, and be able to do better measurements..

This is not something I believe is true, but something I know is true because I did it, and got my measurements.. sorry..but you're just plain wrong...


If you want something DIY-ed I am afraid that building something with 100 dB S/N is (unfortunately) not easily done.

Actually it is, very easy.. the other day I made a distortion analyzer for less then something like 30 euro, capable of detecting -115dB THD+N, using a FFT-scoop, I could see that my 8-part wienbrdige oscilator has better than -120dB THD.. just a couple of NE5534's and a hand full of resistors/caps and 2 100 Ohm multiturn pot's...



http://www.ni.com/pdf/products/us/pxi4461.pdf -- $3,995 for US Delivery.

NI PCI-6220 (16 Analog Inputs, 24 Digital I/O) $375 you won't need more than that ...
It will give you better than 140dB smallbandwidth (!) resolution
 
quote:
The Creative products (2ZS and 4Pro) do not have a 192 kHz recording capability... The Phase-X-24 does.

Nope it does not...
# 24-bit / 192-kHz analog signal processing
# 24-bit / 96-kHz digital signal processing
mmwwooeehahahaa ... funny guys at terratec.

Patience, patience. How long ago was it that you couldn't even find these in a "typical" soundcard? We'll just wake up one day and find 32/512 cards at the corner computer shop.

That won'y change the nature of this thread because by then we'll want to see another leading zero, or two. Anout to 50kHz, "just to be on the conservative side".)