Dear list,
Last week I asked for suggestions regarding a replacement for our HP3561A spectrum analyser. I promised to post a summary of responses, and, in no particular order, here they are. I will try out a few options, & I'll let anyone who cares know what we decide on
bob
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My Daqarta software uses a standard PC sound card to do spectrum analysis,
color spectrograms, synchronous averaging (for evoked potentials, etc) and
stimulus signal generation. The cost is US$99 for a lifetime license,
entitling you to all upgrades. The next version (v3.50, in about a month) will
add a pop-up voltmeter, frequency counter, spectral peak tracking,
and peak super-resolution.
Note that it only supports standard 16-bit stereo cards at present.
Since Windows sound cards provide no calibration information (and
Windows provides no way to access it even if they did), you will need
to do the calibration yourself. Daqarta can calibrate the attenuator
step sizes with its Auto-Calibration option, but you will need to provide
an absolute full-scale range calibration using an external known
signal level. (But the Help does discuss some "tricks" to use a cheap
DMM if you have no test equipment.) Once calibrated, Daqarta keeps
track of all ranges and levels, and can display in Volts or User Units,
including SPL if you provide a frequency response file.
D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Signal Generator
Science with your sound card!
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I'm still happy with the two-channel Stanford Research SR780
I bought ...
(from Michael Akeroyd: maa@xxxxxxxxxxxxx)
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Dear Bob,
we use a stanford research SR780
which works very well.
Cheers, Lutz
Dept. Biologie II
Ludwig-Maximilians-Universität München
Großhadernerstr. 2
82152 Martinsried, Germany
phone: +49 89 2180 74 314
fax: +49 89 2180 99 74 314
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Dear Bob,
we use a stanford research SR780
which works very well.
Cheers, Lutz
Dept. Biologie II
Ludwig-Maximilians-Universität München
Großhadernerstr. 2
82152 Martinsried, Germany
phone: +49 89 2180 74 314
fax: +49 89 2180 99 74 314
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********************************************************************************************** The following is a link to an Ono Sokki, which, incidentally, appears to have a touch screen rather than buttons.. This looks good - 4 channel, 24bit, 40 kHz FFT real time rate, Windows XP and lots of connections ! http://www.onosokki.net/catalog/viewProduct.cfm?ProductID=78&a=1&CategoryIDTrail=4,27 It's different from their CF 5210 FFT Analyser, which Mike Stone (in Brian Moore's group) says they found very unreliable & disappointing ************************************************************************* We have happily used an Ono-Sokki CF-350Z for about 14 years, which was an update of an older Ono-Sokki model (which we also still have two of). What the current status of these instruments is, I don't know, but they have been very useful and pretty much trouble-free. (From Stuart Rosen) Yours -- Stuart *************************************************************************************************** Bob, We have the Agilent one you mention & I really like it - it's solid & doesn't crash like some of the PC/windows ones I've come across. The down side was that I think we had to pay extra for mic. inputs etc. I've also used ones by Ono-sokki in the past which have been good, but BIG - I haven't used recent ones though. What I have found in the past is that prices are often negotiable if you have two or three alternatives. We also have a LeCroy WaveRunner 64Xi oscilloscope which has built in FFT as a Maths function, for straight forward spectral measurements it is OK - I haven't really used it in anger - but it runs on windows! (B.B. We (Bob's lab) use LeCroy Waverunner scopes - they're great if you can get over the fact that they're only 12-bit) (from Richard Baker) ********************************************************************************************************* 've got an HP 35670A and it is a nice instrument but unless you feel you really, really need the physical interface of a spectrum analyzer, I suggest you get a laptop computer with a data acquisition interface. You'll get more channels, high resolution (20 or 24 bit), higher bandwidth, and the data will already be on a computer. Besides the physical size, the big problem with the HP35670a is the difficulty in getting data in/out. You only have a 3.5" floppy disk and HPIB - there is no other way to get data in or out. The analyzer is only 16 bit and you are limited in your bandwidth. Because of that reason, I use my HP almost exclusively as a function generator/simple meter and do my data acquisition with my laptop. A similar two channel analyzer is available from Stanford Research SRS 780 and 785 http://www.thinksrs.com/products/SR785.htm Similar performance to the HP 35670A but about half the price. If I were looking for a new analyzer I would instead a rugged laptop and one of the following DAQ systems national instruments (espcially the USB 9233) with the sound and vibration labview kit. http://www.ni.com IOtech (several products) http://www.iotech.com/ DataTranslation (several products) http://www.datx.com/products/dataacquisition/usb/default.htm Ralph -- Ralph T. Muehleisen Assistant Professor, Civil and Architectural Engineering Illinois Institute of Technology, Chicago, IL 60616 tel: 312-567-3545 fax: 312-567-3519 email: muehleisen@xxxxxxx url:http://acoustics.iit.edu/muehleisen ********************************************************************************************************* ********************************************************************************************************* Hi Bob, We've been using a 2-channel HP 35670A analyzer for about 15 years. It's been a great instrument -- very robust, accurate, well-documented, easy-to-use. Recently though we've been relying more and more on PC/Matlab analysis. The flexibility (mainly in displaying results) wins in many cases, especially when you want to do specialized measurements repetitively. The tradeoff is in SNR, unless you get an external audio interface (which would still be far less expensive than the HP). Regards, Pat Patrick M. Zurek President Sensimetrics Corporation 48 Grove St. Somerville, MA 02144 Tel: 617-625-0600 x237 Fax: 617-625-6612 email: pat@xxxxxxxx web: www.sens.com ********************************************************************************************************* Hi Bob, You might take a look at www.praat.org and http://www.phon.ucl.ac.uk/resource/sfs/ Best, Heriberto (avelino@xxxxxxxxxxxx) *************************************************************************************
Praxis,
via
Professor
David W. Smith
Depts.
of
Psychology and Otolaryngology
Center
for
Smell and Taste
(NB this is a software solution)
********************************************************************************************************* Hi Bob, We've been using a 2-channel HP 35670A analyzer for about 15 years. It's been a great instrument -- very robust, accurate, well-documented, easy-to-use. Recently though we've been relying more and more on PC/Matlab analysis. The flexibility (mainly in displaying results) wins in many cases, especially when you want to do specialized measurements repetitively. The tradeoff is in SNR, unless you get an external audio interface (which would still be far less expensive than the HP). Regards, Pat Patrick M. Zurek President Sensimetrics Corporation 48 Grove St. Somerville, MA 02144 Tel: 617-625-0600 x237 Fax: 617-625-6612 email: pat@xxxxxxxx web: www.sens.com *********************************************************************************************************
Dear Bob
Use B&K's Pulse - a mostly
software-based solution - with trustwothy and reliable signal analysis.
I worked on the project myself
- including the FFT - and I was proud of it. I would still recommend
it, although I don't work at the company anymore so I'm a little less
biased :-)
I have no idea if the price is
tolarable. See the product on http://www.bksv.com/2746.asp
Best regards
Lars Bramsløw
Audiology
Oticon A/S
Kongebakken 9
DK-2765 Smørum
Denmark
Oticon A/S
Kongebakken 9
DK-2765 Smørum
Denmark
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-- Dr. Bob Carlyon MRC Cognition & Brain Sciences Unit 15 Chaucer Rd. Cambridge CB2 7EF England Phone: +44 1223 355294 ext 651 Fax: +44 1223 359062 www.mrc-cbu.cam.ac.uk
