Test Equipment Recommendations Please - diyAudio
Go Back   Home > Forums > Design & Build > Equipment & Tools

Equipment & Tools From test equipment to hand tools

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 21st February 2012, 04:44 AM   #1
diyAudio Member
 
Join Date: Feb 2012
Location: Brisvegas
Default Test Equipment Recommendations Please

I need to start collecting some calibration equipment to test some new speakers I am building. Currently I am looking at the Earthworks Audio Measurement Series M30 microphone. I also need a 48v phantom power, does it matter what brand I use?

I need some test software so I am open to suggestions on what works well and reasonably priced. I also figure I need to use my laptop or one of my desktops sound cards. Are there any minimum requirements to work with this microphone / recommended software?

Really new to this side of speaker building and would like to buy the right gear first time. I would really appreciate any assistance you can offer.
  Reply With Quote
Old 21st February 2012, 06:21 AM   #2
gootee is offline gootee  United States
diyAudio Member
 
Join Date: Nov 2006
Location: Indiana
Blog Entries: 1
You could try the free ARTA software suite.

I picked up a new Superlux ECM999 measurement mic on ebay, for a very reasonable price, after reading some reviews and looking at the frequency response and other specs.

Just to be able to play around with the measurement mic and ARTA, I bought a "TubeMP Studio" mic preamp on ebay, which also provides the 48V phantom power. I don't know how good it is but I got it new for about $40, last year. They seem to have several different TubeMP models on ebay, now.

I also got the necessary cables from another ebay seller. The TubeMP Studio has both three-pin XLR female and 1/4-inch mono female input jacks, and both 3-pin XLR male and 1/4-inch mono female output jacks. I used the 3-pin XLR input for the measurement mic's cable, with 48-Volt phantom power provided by the TubeMP, and used the 1/4-inch mono output so I could easily use an adapter on the other end of the cable for my soundcard input.

If you do some searches, you'll find that there are LOTS of good threads here at diyaudio about equipment and software for speaker measurements.

Regards,

Tom

Last edited by gootee; 21st February 2012 at 06:25 AM.
  Reply With Quote
Old 21st February 2012, 08:16 AM   #3
diyAudio Member
 
Join Date: Feb 2012
Location: Brisvegas
Thanks for the advice Tom. I want a measurement microphone that comes with a calibration chart to dial out any imbalance in the microphone, so I need to look at something a little more upmarket.

I did look at the EarthWorks Audio ZDT 1021 but itís like $1300, between it and the M30 it is over $2000 with GST and freight, and while looking at the TubeMP you mentioned, I noticed the affordable phantom power supply only seem to go to 20kHz-25kHz, so perhaps I should be looking at the marginally cheaper M23 microphone ($459 + shipping) if I am not going to spend the dollars on the megabuck preamp?

I downloaded the user manual for the ARTA software (which by the way is 79 euro if you want to use all the features) and it was filled with math equations. Is there any software where I donít need a degree in math to use?
  Reply With Quote
Old 21st February 2012, 08:30 AM   #4
diyAudio Member
 
Join Date: Jan 2012
Hi
have you had a look at SPECTRAPLUS.com
  Reply With Quote
Old 21st February 2012, 01:14 PM   #5
pby is offline pby  United Kingdom
diyAudio Member
 
Join Date: Nov 2011
Location: Swansea, UK
Quote:
Originally Posted by Silent Screamer View Post
Thanks for the advice Tom. I want a measurement microphone that comes with a calibration chart to dial out any imbalance in the microphone, so I need to look at something a little more upmarket.

I did look at the EarthWorks Audio ZDT 1021 but itís like $1300, between it and the M30 it is over $2000 with GST and freight, and while looking at the TubeMP you mentioned, I noticed the affordable phantom power supply only seem to go to 20kHz-25kHz, so perhaps I should be looking at the marginally cheaper M23 microphone ($459 + shipping) if I am not going to spend the dollars on the megabuck preamp?

I downloaded the user manual for the ARTA software (which by the way is 79 euro if you want to use all the features) and it was filled with math equations. Is there any software where I donít need a degree in math to use?
Not sure what you mean by dialing out the imbalance in the microphone but if you were planning to EQ it out then doing so will most likely make measurements worse.

Also unless you have access to anechoic chamber there isn't much point dropping 2 grand on an earthworks as the measurements would be fairly meaningless without a treated room.

Preamp and ADC is just as important as the room and microphone. You may want to look at a solid state preamp over a tube preamp for measurement purposes. fmr has a great pre that has superb transparency that isn't too expensive.

The truth is theres no easy way to make meaningful measurements at home, and spending money on equipment without knowing the limitations is just wasting money. What exactly are you trying to calibrate?
  Reply With Quote
Old 21st February 2012, 10:30 PM   #6
diyAudio Member
 
Join Date: Feb 2012
Location: Brisvegas
Thanks pby I downloaded the pdf for the FMR Audio RNP8380 and will take a more detailed look at it tonight. I like his honest approach and at ~$500 is a little more palatable than $1300.
No I donít have a anechoic chamber, but I am looking to acquire test equipment that is not going to be dissatisfactory 5 minutes after I buy it. Experience has taught me not to skimp and have to spend twice.
So I am looking for something that is marginally better than middle of the road first time up. Not looking for over the top but donít want garbage either.

If I spend $1500 all up on test gear and I spend $10k on speaker parts, to me that seems like a reasonable balance to achieve the end goal of quality sound.
But I donít want to spend mega bucks on the speaker parts only to be let down by my test gear when it really matters.

Sorry if I havenít used the right terminology as I am fairly new to all this but I wanted a quality microphone that provides a calibration chart so any slight imperfections that are inherent in the microphone can be dialled out by including the discrepancy in the software to cancel the imperfections out, giving a neutral microphone (as far as the software is concerned). Earthwork provide a graph of the imperfections for $50 extra, so the detail can be provided to the software to counteract the microphone imperfection effect.
  Reply With Quote
Old 22nd February 2012, 11:38 PM   #7
pby is offline pby  United Kingdom
diyAudio Member
 
Join Date: Nov 2011
Location: Swansea, UK
Quote:
Originally Posted by Silent Screamer View Post
Thanks pby I downloaded the pdf for the FMR Audio RNP8380 and will take a more detailed look at it tonight. I like his honest approach and at ~$500 is a little more palatable than $1300.
No I donít have a anechoic chamber, but I am looking to acquire test equipment that is not going to be dissatisfactory 5 minutes after I buy it. Experience has taught me not to skimp and have to spend twice.
So I am looking for something that is marginally better than middle of the road first time up. Not looking for over the top but donít want garbage either.

If I spend $1500 all up on test gear and I spend $10k on speaker parts, to me that seems like a reasonable balance to achieve the end goal of quality sound.
But I donít want to spend mega bucks on the speaker parts only to be let down by my test gear when it really matters.

Sorry if I havenít used the right terminology as I am fairly new to all this but I wanted a quality microphone that provides a calibration chart so any slight imperfections that are inherent in the microphone can be dialled out by including the discrepancy in the software to cancel the imperfections out, giving a neutral microphone (as far as the software is concerned). Earthwork provide a graph of the imperfections for $50 extra, so the detail can be provided to the software to counteract the microphone imperfection effect.
I'm not entirely convinced this is the right approach. There are room acoustics/preamp/adc which isn't be accounted for. You cannot simply dial them out.

Unless you're prepared to go hire a chamber, budget equipment here will probably suffice for your needs. Behringer has a really inexpensive measurement microphone called the ecm8000 and you can just pair it up with a behringer mixer or preamp. While high end gear will give you more precise results, you would still be limited by the room acoustics. It would be a waste of money to spend it on mics and pres for you, as they can't correct acoustics.
  Reply With Quote
Old 23rd February 2012, 12:01 AM   #8
diyAudio Member
 
Join Date: Feb 2012
Location: Brisvegas
I guess what I am looking for the most precise measurement I can afford, it would be great to have an anechoic chamber, but all factors considered at the end of the day I will using the speakers in a real room where there are objects that will affect the sound output.

I am currently looking at an up market digital crossovers that can do room equalisation, so I figure as long as I can measure the room and speaker accurately, I am in a good place to dial out the environment to a certain degree.

The digital crossover have such infinite adjustability I can adjust the digital crossovers to suit the room conditions should I need to move them to another room.

If we were talking strictly passive crossovers I might think quite differently about things.
  Reply With Quote
Old 23rd February 2012, 04:54 AM   #9
gootee is offline gootee  United States
diyAudio Member
 
Join Date: Nov 2006
Location: Indiana
Blog Entries: 1
I thought that the reason they called them "measurement mics" was that they have a flat frequency response, already. The plots I have seen for the model I bought were so flat that any imperfections will be totally-swamped-out by other measurement variations.
  Reply With Quote
Old 23rd February 2012, 05:14 AM   #10
diyAudio Member
 
Join Date: Feb 2012
Location: Brisvegas
Generally the better the quality the flatter they are, but just like a speaker none are perfectly flat so they provide a map of the imperfections so you can add it to your software, and the software artificially corrects the imperfections in the microphone by applying adjustment to the reading form the microphone.
The way I figure it the more perfect you can make the reading, the better informed you are to make a call on thing like applying adjustments to any dips in the response curve. If the reading says you high and you’re really low because of inaccurate equipment, you could potential tune an even greater problem into the speaker response.
Its the theory I’m working on I could be wrong but it makes sense to me...
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Test Equipment MicroMinded Solid State 20 28th April 2011 06:37 AM
bench equipment recommendations for newbie hjcooper Instruments and Amps 2 28th March 2007 03:07 PM
Recommendations for test equipment jmikes Multi-Way 3 16th November 2004 07:21 PM
Soldering equipment recommendations? geolemon Solid State 60 4th June 2004 04:58 AM


New To Site? Need Help?

All times are GMT. The time now is 06:04 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2