Laptop requirements

[augerpro]

I'm looking for a laptop to do measurements outside. I'll be using Soundeasy and the M-audio mobile pre.

What are the minimum requirements I need?

Also is it possible to just run the mic outside and run a cable back to the mobilepre inside the house? Any problem with running a long (@75 feet) cable? I have a field in front of my house so if I can keep from buying a laptop just walk 75 feet out my door I would like that.

[Vinny]

As you will have those external stuff through USB anyway, pretty much any laptop can do the job.

However, as you go outside, I'd suggest you get a sturdy one like IBM or MSI prebuilt(which you can get parts by yourself and fix it by yourself if anything happens).

I don't recall the strength of XLR in the m-audio would give for mic. But check it out and see whether it can take 75feet or not(it should be able to)

[joecarrow]

Microphone cables in a live sound setting are frequently 50 feet long. As long as it's XLR and the gear can handle it, I say you can get by without a laptop. Of course, you'll also need to run the signal out to your speaker... but I think this can be done with less than a laptop.

[Paul W]

I used a 75' XLR mic cable for some outdoor measurements a few weeks ago and had no problems. (actually 50' + 25' cables)

[fjhuerta]

I'm using a 1 GHz Centrino with 512MB RAM and a Sound Blaster Audigy 2ZS. It's overkill - way too much power for that kind of measurements (no joke).

The PC I used before I gave it away was a 1998 Compaq Presario with a 450 MHz PII, 384 MB RAM and a Santa Cruz sound card. And it did everything I needed perfectly well.

[augerpro]

Thanks for the replies everyone. Ya, I wouldn't think an XLR cable would be much of a problem. What about speaker cable? Should be fine with say 12- 14 gauge?

BTW the Behr. UB802 is discontinued, and PE is already out of stock. Now I'm just waiting for newegg.com to get the maudio mobilepre back in stock...

[Mudjock]

I have a spare UB802 if anyone is looking for one... I switched to a Mobilepre-based laptop setup.

[Licinius]

I've been lurking for months, as I really don't have anything useful to say in the company of quite a few really sharp folks around here, but I've been looking at building myself a new set of speakers and doing some measurements just because it seems interesting (and therefor been looking around for the mobile pre) and Amazon has it for $128 with free shipping.

http://www.amazon.com/M-Audio-MobilePre-Preamp-Audio-Interface/dp/B0000TP57E/sr=8-1/qid=1159392692/ref=pd_bbs_1/002-5462979-4301664?ie=UTF8&s=electronics

[augerpro]

I've been lurking for months, as I really don't have anything useful to say in the company of quite a few really sharp folks around here, but I've been looking at building myself a new set of speakers and doing some measurements just because it seems interesting (and therefor been looking around for the mobile pre) and Amazon has it for $128 with free shipping.

http://www.amazon.com/M-Audio-MobilePre-Preamp-Audio-Interface/dp/B0000TP57E/sr=8-1/qid=1159392692/ref=pd_bbs_1/002-5462979-4301664?ie=UTF8&s=electronics

You ROCK! Thanks for the heads up man :T

[Outfitter]

Try Zipzoomfly, $119 with free shipping.

http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=361124

[Marzen]

I recently upgraded to a 2Ghz AMD64 w/ 1 gig of memory. Much faster at optimizing xo's in SE v12 than my previous 1.2G/512K pc. Digital filter operation is smoother as well.
I use a 50ft XLR mic cable with preamp box and run it outside along with 50ft of 14awg spkr cable. I'm in the city so I envy your locale.
-Ward

[knifeinthesink]

i most definately do not have the answer to this, but doesn't cable start to have significant issues with capacitance, inductance, etc when your dealing with lenghts like that. If so, that would probably make a mess of things.

I think the mobile pre is a pretty old card and maybe not the best value. I just found this on the web and it got my heart racing. http://www.creative.com/products/pro...&product=15167

I tried an emu 1616, which really impressed me. Of course its a much more expensive unit but I've heard consistently high praise for emu stuff.

[augerpro]

Would something like this work: http://www.partsexpress.com/pe/showd...number=241-780

[knifeinthesink]

This is a snippet I found on some companies site. In a nut shell, in about five minutes of reading google hits for "long cable run" I came to the conclusion that if I were in your shoes there is no way I would run long cables to take measurements. I cant say with certainty that it will mess you up but I read enough that I wouldn't trust the measurements. You can pick up laptops these days for about $500 that I suspect would run any of the measurement programs.

"The capacitance of the cable run, together with input impedance, forms a low pass filter. As the cable run gets longer the capacitance increases, thus lowering the cut-off frequency.

Inductance is introduced by the transformer in the microphone itself and the mic splitter. A mathematical model could be made to predict the exact effects for a given microphone, splitter and preamplifiers, but it is sufficient to say that the frequency response will be changed. The effect could be anything from a peaked response, a dip, a low pass or any combination. "

[ThomasW]

All but the most expensive test mics aren't accurate at very high frequencies.

If your using a ECM8000 I wouldn't worry about the minimal high frequency attenuation caused by a longer cable run.

[augerpro]

Where can I find these calibration files for the ecm8000?

[Marzen]

I can email you the cal file if you can't find it online.
-Ward