Friday, July 24, 2009

Even more Audio Card Joys

So, I got the MAudio Firewire Solo last weekend. And it went back also.

It wasen't DOA. It lit up when I plugged it into my desktop machine (Vista Ultimate). I installed the latest drivers from maudio, shutdown, plugged in the solo, and booted up. The control panel said no card found when I opened it after boot.

I then installed the drivers on my laptop (Vista Basic), shutdown, plugged in the MAudio into the laptop, used a 1200ma 12vdc universal power supply to power the MAudio, and nothing again - the control panel says no device found.

When I plug in the sound card, it doesn't add any devices to the device manager.

So, it went back... sigh....

Now I need to find an audio card, used, portable, that will work with ARTA and LspCAD and SpeakerWorkshop.

Been looking some more at the boards, and people seem to like the M-Audio Transit and the Edirol UA-1EX for under $100.

I did a google search for 'Edirol ARTA' and found some German audio boards (gotta love Google Translate!) where they complain about Edirol and ARTA, and people who were saying they were switching to the Transit. So, a M-Audio Transit it is...

I hope I don't have any latency problems. My fear is probably unfounded - most of those M-audio complaints seem to be a year or two old.

Friday, July 10, 2009

Audio Card Joys

My Dell-sourced Creative X-Fi card came in today.

And it is going right back out. It is DOA - totally freezes my laptop every time I plug it into the Expresscard slot.

There is a possibility that this is a good thing, not a bad thing. I am getting my $ back for the card. And I just bought a M-Audio Firewire Solo for $120 used online.

Although $40 more than the Creative, it appears to be a favored sound device in the DIY speaker design crowd. It has phantom 48v power for a mic, balanced outputs, and very low latency.

Hopefully my jig is done this weekend, and I should be testing next weekend. Cross my fingers!

Thursday, July 2, 2009

Getting Jiggy with it

JustMLS, ARTA, Speaker Workshop - they all have a common theme - they are software packages, not software + hardware packages. Praxis, Leap, Clio, MLSSA - these are packages of software and hardware for measuring speakers.

The software-only packages are a bit less expensive (ARTA and LspCAD Std can be had for $350 USD or so for both), but require the user to rig up hardware capable of repeatable, consistant measurements (average of $50 to create the 2 jigs for them). Praxis ($1000) and LEAP ($1500) provide you with the hardware also, making it easy to just get to work.

Since easy costs a lot more in the cash department, I am gonna try to get ARTA and/or LspCAD&JustMLS to function - that would be maybe $400 for ARTA, LspCAD Standard Edition, and a jig that will function for both products & hold the Wallin Preamp.

JustMLS and ARTA both provide details on the 'jig' necessary to use the software packages in question. A 'jig' in this case is a box with some connectors, resistors, and other stuff necessary to cable your speaker to the sound card.

I have almost ZERO electrical knowledge - kinda bad for someone who wants to create his own speakers. So, I gotta learn as I go thru this.... I bought the parts to create jigs from Mouser, and have some items already in my stock. I have been playing with the stuff from Mouser, and I think I can get the mic preamp, ARTA and JustMLS components all into one project box.

You need a program that can draw basic shapes. I have a friend with Adobe Illustrator on his terminal server, and he kindly gave me access via Remote Desktop and I drew away.

If you order your parts online from a place like Mouser, then each part has details such as the size of the part, and links to everything you bought is in the My Mouser part of the website. This makes it really easy to draw & place drill holes for each part, so you can print your templates, tape them to the enclosure, and drill holes for each component you need to mount.
I have a Hammond enclosure, sized 5.9x3.2x1.8 inches, Part# 1591DSBK. One small side is 3.2x1.8 inches. Easy enough to create a graphic of that size. One larger side is 5.9x1.8 inches - just a different graphic.

Once I create the new graphic, I use the View menu to show the rulers, in inches. Then I can draw exact size circles, squares, or whatever, and label them.

Above are some pictures of the jig that I started today - notice the printed out templates that I taped all over the jig box. I need a few more parts to finish, will post the final product pics when completed. Wonder if all this effort is worth it?

Saturday, June 27, 2009

Reference Books for Loudspeaker Design

I find a zillion reference books on Amazon. However, there are a few that are more highly regarded than others.

Testing Loudspeakers- Joseph D'Appolito - still considered a standard reference book with regards to the practice of testing loudspeakers to get their basic parameters.

Loudspeaker Design Cookbook - Vance Dickason - a good reference guide for those new to loudspeaker design - it provides basic info regarding all the major steps in a build, and you can google your way thru more details on any of these topics.

So, I will purchase those 2 if/when I get the measurement jigs/mic/software all working to my satisfaction.

Additional Speaker Creation Software

I have quickly identified several additional software tools that I am positive I will need to use for the creation of a loudspeaker. Figured I would save you the time in hunting these down. As I find more useful software, I will post it here.

Google Sketchup - - a free, intuitive program to draw 3D images of your project.

Unit Converter - - a free program to convert between different units of measurement - great for metric to english unit conversion

GIMP for Windows - - a free photo editing tool, similar to Photoshop but without cost

FSCapture - - a fantastic freeware image capture tool - useful for making your screenshots, whether you put the screenshots into a document or post them on the internet - hopefully you are creating a word document for your project, with notes, drawings, etc???? Even better, a file folder to store your different files in for future reference.

OpenOffice - - a free office suite, with capabilities similar to Microsoft Office. Useful for creating documents and PDF files, and the spreadsheet program can assist in automating some of those math equations you might use whilst designing your speaker, and the drawing program can assist you in diagrams, crossover design, etc....

Audacity - - a free replacement for the Windows Sound Recorder - again, useful for recording and analyzing sounds

DPC Latency Checker - - a program to check your audio hardware for latency - latency is bad when it comes to speaker measurement software

CutList Plus - - a commercial (pay) program that will allow you to layout all of your cuts before you pull out your saw. This should save quite a bit of time, as you simply need to pull out the board, lay down the cuts based on the sheet, and go to town with minimal waste and no lost time planning your cuts in advance - I ain't gonna buy this until I have successfully created my first 2-way speakers and I am satisfied.

Friday, June 26, 2009

Equipment Purchased

Well, I have bitten the proverbial bullet, and purchased some stuff to experiment with speaker measurements.

I purchased an Expresscard SoundBlaster X-FI from Dell, for $82 incl Tax S&H. Hopefully it is a good compromise - enough quality to perform measurements, no lag or latency issues since it is plugged into a slot, not a USB/Firewire port, and less than $100.

The next purchase was $79 at Mouser. This covered 2 generic plastic boxes for creating the ARTA and LspCAD jigs, one Hammond enclsure for the Wallin preamp, and some resistors, capacitors, diodes, chassis mount banana jacks and rca jacks, and whatnot to round out the inventory I already possess.

Of course, I can't test without speakers to test with. $60 to Parts Express ($16 for S&H - yikes!) to purchase 2 Goldwood 1" Tiatnium tweeters, 2 generic 6" woofers, and 50' of 16ga speaker cable. If I get impedence and FR measurements, then I will get some xover parts for testing, and find someone to assist me in making 2 test boxes.

Over $220 just to test out a hobby. Once I build the jigs and Wallin, I will post pictures. Friggin expensive test, hope that the equipment all works. To be honest, it doesn't seem like some resistor jigs and a homemade mic & preamp will work for squat, but you never know till you try.

Thursday, June 25, 2009

Speaker Measurement Test Equipment

Now that I have downloaded a couple of demo packages, I need to sort out the hardware.

Part of my choice for LspCAD and ARTA is that I can create some semi-inexpensive jigs, and actually use the 2 programs to measure speakers.

If it doesn't work, I don't loose a huge amount of cash. If it works, then I keep using the same equipment and software.

I would like to run the tests outdoors, in an empty field, so I don't have to worry about echo and room response, etc... Based on that hope, I plan on the following rig:

Dell Vostro 1510 Laptop, Vista 32bit, 4gb RAM, Dual-Core CPU (already own it)
Soundblaster X-Fi Expresscard (gotta buy)
JBL GTO Amp - I have a car stereo amp in my truck, powering 2 coaxials and a 10" woofer. I have easy access to the amp, so I can use it for testing.

There are a few items I will have to solder together also...

ARTA Jig - - looks like $20 in parts to make a jig for measurements.

LspCAD Jig - - another $20 to create a box with resistors to measure loudspeakers with LspCAD.

Wallin Preamp2 & Panasonic WM-61a Microphone -
I have 80% of the parts already for a Wallin Preamp, and I bought 3 of the circuit boards in 99/00 when they were being made (a buddy wanted a portable powered Mic for less than $50, this was it) back in the day. If this works out, I will get the mic calibrated - if not, not a huge loss.

Looks like the total outlay for the SB card will be $100, and the 2 jigs / PreAmp / Mic will be $85, so that is $185 just to test a hobby out... wonder if I should do it or not?