Wanted : Audio Spectrum Analyser / Dynamic Signal Analyser / Network Signal An

[backflipper]

Hey
As per the subject I am looking for a Audio Spectrum Analyser / Dynamic Signal Analyser / Network Signal Analyser

So far the following have caught my eye:
Stanford Research SR760 and SR780
Hewlett Packard 35665A Dynamic Signal Analyzer

Can anyone recommend any other or offer any others?

Thanks!

[PartialDischarge]

Also look at the hp 3561A or if you can live with just a network analyzer from 0 to 150Mhz the 3589A

[Zucca]

If you just need an Audio Analyzer, I have a QA 400 to sell. PM me if you are interested.

http://quantasylum.web707.discountasp.net/content/Products/QA400.aspx

[Ice-Tea]

I have a HP35670A for sale, but I haven't checked it yet. If interested, PM me and I'll check her out ASAP.

[backflipper]

I should say that I don't have thousands to spend on old gear.  I like the old gear but I need to be sensible as the old gear is massive and the new stuff is small :-)

[thm_w]

If you don't have thousands then you likely can't afford any of the items you've listed.

Best bet is get the QA400 or a USB DAC, depending on what you're trying to do (if its audio). Input voltage range of QA400 might be limited.
https://html.midifan.com/review/2i2/[MME]%20Scarlett%202i2%20USB%202448.htm

If its something else, then best to post here what you are trying to achieve.

[IanG3XYV]

Hi backflipper, I've sent you a pm.

[ap]

It really depends what you are after. If your focus is high S/N ratio, e.g. the R&s UPL is a cost efficient choice. A good audio card even better value, but is has its limitations.
If you need to measure spectral noise density, a 35665A is good value.
So you should really define what you need in terms of functions/parameters.

[backflipper]

It really depends what you are after. If your focus is high S/N ratio, e.g. the R&s UPL is a cost efficient choice. A good audio card even better value, but is has its limitations.
If you need to measure spectral noise density, a 35665A is good value.
So you should really define what you need in terms of functions/parameters.

You right I should have specified that I am interested in audio measurements.  I like the look of the Rohde & Schwarz UPL gear but they seem to be quite a few on ebay that are not selling at the prices they have been listed at.

I am really interested in the QA-401 so I may just bite the bullet and get one new to try it out.

Thanks for all you responses it has been very helpful.

If there is anyone on the forum who would like to talk about audio measurements it would be great to hear from you.

Thanks again.

[tecman]

I have an Advantest R9211C for audio/lf work.  Not as intuitive as HP, but mostly an equal to 35660/70 in performance.  One nice thing is the built-in printer (an option) for having a hard copy.  You can occasionally find the R9211 for a reasonably good price on ebay.

http://www.cieri.net/Documenti/Misure%20audio/Advantest%20-%20R9211%20Series%20-%2090%20dB%20FFT%20Analyzers%20(1990).pdf

paul

[Oldtestgear]

I have an HP 3561A listed on eBay now. Priced at £395 plus shipping. I am more than happy for anyone to check it out before committing to buy. Located in Torquay. PM ME IF YOU ARE INTERESTED.

Phil

[rhb]

If you're only interested in audio, a good quality 24 bit/96 KHz  sound card and proficiency with Octave or MATLAB  is probably the best price-performance.

What that won't get you is someone else having done all the hard thinking for you.  It will require  mastery of DSP and the use of the Fourier transform.  "Random Data" by Bendat and Piersol is the best reference if you have learned calculus.

You don't say what you want to measure, but as an example consider this.

The task is to measure the transfer function of an RIAA  preamp.

Write a program which feeds a set of known signals to the DAC of the sound card and record the ADC output using a cable from the input to the output..  With two outputs and two inputs you have four equations which you can solve for the errors in the two DACs  and the two ADCs.  If you take a long recording and autocorrelate it you can get the amplitude spectrum of the combined transfer function of the DAC & ADC to whatever resolution you want.  Once you have calculated the corrections, put the preamp in between, adjust the levels appropriately and measure.

You won't get the answer as easily as by spending  a bunch of money.  But you will know a lot more.

Search online for "Max Wein, Mr. Hewlett and a Rainy Sunday Afternoon" by Jim Williams. There's a thread in the forum about building a Wein bridge oscillator which has additional information.

Have Fun!

[Keicar]

Personally I'd be inclined towards the QA-401, I'm tempted to get one too (despite already owning a 3562a).

Cheers,

Karl.

[Zucca]

I got a good deal on a QA-401, otherwise I will use my QA-400 (now on sale  , just PM me) with something like this:

https://oshpark.com/shared_projects/w7kQ4aim

Maybe a cheap used QA-400 with a decent front end can change the business case...