OROS OR35 vs Spec. Dynamics Cougar

[271828]

Hello vibe experts. I would appreciate some advice here.

I've been asked to decide between two vibration analyzers for our research team.

Brief background: We do floor vibration testing on lab specimens and real building floors. We use one output channel to send signals to our big shaker, one input channel for our shaker force transducer, and 2-6 input channels for accelerometers. We use typical burst chirps during our modal tests and estimate FRFs. We also do other types of even simpler tests such as walking on the slab and measuring the accelerations, decay tests, and impact hammer tests. Pretty easy stuff from a ME or AOE standpoint, LOL, but hey, we're civil stuctural guys so it's cool to us.

I've narrowed it down between:

http://www.oros.com/EN/products/analysers/or35.php

and

http://www.spectraldynamics.com/COUGAR.htm

The OR35 is just a little more expensive, but I think it's probably a much nicer system. Can anybody confirm this?

How are OROS' customer service, overall quality, and durability?

Any insight would be greatly appreciated.

 

[GregLocock]

Can I strongly recommend that you get the salesdroid in, and have him analyse a DAT tape of your typical measurements, and ask him to duplicate your known results (you'll need to do that anyway) ? If you want to be nice send him the tape in advance, and the expected results. If not, not. Calibration is often a cause of some confusion to salesdroids.

I've done this in the past and it quickly filters out the wannabees.





Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[271828]

Good idea Greg, but no time. I was asked to start this search Friday and the application is due in the next 2.2 hours.

Gut feel for which is better?

 

[GregLocock]

Oh, and your requirement for chirp, or longer sinesweeps, /may/ give them problems, particularly if you want to do a peak hold transfer function with phase, which seems like a sensible test in your context.





Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[271828]

Out of time. Going with the OROS35.

It uses an ethernet connection instead of a hideous SCSI connection. We've had never-ending problems with SCSI connections in the past. This was the main thing that swayed me.

They also get the "gut feel" points because I've contacted a tech guy very fast both times I called. In the past, we've had trouble with our SigLab units and got little help from Spec. Dynamics, although this is anecdotal. Our SigLab units have been difficult to deal with, so the Cougar loses points by association. OROS only wants $1700 more, and I think the ethernet conn vs SCSI is worth that all by itself.

I hope I'm right because that was a $20k decision.

 

[271828]

Oh, forgot one other thing that added to the "gut feel" part. When I call OROS' USA office and ask a question, they send me right to a tech support guy in that office. When I call Spectral Dynamics and ask ANY question, they take my name and have their regional guy call me back. I guess I could save his number and just call him.

It's the little things that make or break deals sometimes.

 

[Rob45]

There's no question in my mind that, between those two, Oros is the better choice, but for that amount of money I'd have considered both Head Acoustics and Prosig.

I definitely would NOT consider LMS; their software, in addition to being buggy, is the antithesis of "user friendly."

 

[271828]

Thanks Rob. Totally stinks though--our funding source fell through. At least I know where to look IF we ever come up with the dough!

 

[Rob45]

And one more small thing:
The one time I contacted Spectral Dynamics via their website, the e-mail reply I received from them contained a virus!
Fortunately, our corporate firewalll identified and dealt with it.

 

[blackeye]

If the funding returns I'd suggest you look at m+p's SO Analyzer at

http://www.mpihome.com.

Very nice to use, very cost-effective particularly as they can use National Instruments h/w.