[Jim]

Sorry if this is a repeat question, but I can't seem to find what I'm
looking for. I need a cheap, easy to use, but effective software to
test some speakers I've built. I need to test the frequency response,
the cross over, distortion, phase. . . that sort of thing.

Can anyone recommend some software?

Better yet. . . if there is a member in the San Francisco Bay area who
is willing to help me test the speakers I could use the help.

Thanks, JH

[James Lehman]

"Jim" wrote in message
oups.com...
Sorry if this is a repeat question, but I can't seem to find what I'm
looking for. I need a cheap, easy to use, but effective software to
test some speakers I've built. I need to test the frequency response,
the cross over, distortion, phase. . . that sort of thing.

Can anyone recommend some software?

Better yet. . . if there is a member in the San Francisco Bay area who
is willing to help me test the speakers I could use the help.

Thanks, JH



The most important testing that you can do at home is done before you build
the speakers. You can find the T/S parameters of the woofers and make the
right box for them.

I wrote software that uses a sound card to measure frequency vs. voltage.
With this you can also read frequency vs. impedance. You can measure all of
the T/S parameters and also the individual and summed outputs of the
crossovers. There are a number of other doohickeys out there that can do the
same thing.

http://www.akrobiz.com/speakers/metal-graphs.html

None of this will tell you how the speakers will actually sound. That is a
matter of choosing the right combination of drivers and putting them
together into a good design.

James. )

[Jim]

Thanks for the information.

James Lehman wrote:
"Jim" wrote in message
oups.com...
Sorry if this is a repeat question, but I can't seem to find what I'm
looking for. I need a cheap, easy to use, but effective software to
test some speakers I've built. I need to test the frequency response,
the cross over, distortion, phase. . . that sort of thing.

Can anyone recommend some software?

Better yet. . . if there is a member in the San Francisco Bay area who
is willing to help me test the speakers I could use the help.

Thanks, JH



The most important testing that you can do at home is done before you build
the speakers. You can find the T/S parameters of the woofers and make the
right box for them.

I wrote software that uses a sound card to measure frequency vs. voltage.
With this you can also read frequency vs. impedance. You can measure all of
the T/S parameters and also the individual and summed outputs of the
crossovers. There are a number of other doohickeys out there that can do the
same thing.

http://www.akrobiz.com/speakers/metal-graphs.html

None of this will tell you how the speakers will actually sound. That is a
matter of choosing the right combination of drivers and putting them
together into a good design.

James. )

[TimPerry]

James Lehman wrote:
"Jim" wrote in message
oups.com...
Sorry if this is a repeat question, but I can't seem to find what
I'm looking for. I need a cheap, easy to use, but effective
software to test some speakers I've built. I need to test the
frequency response, the cross over, distortion, phase. . . that
sort of thing.

Can anyone recommend some software?

Better yet. . . if there is a member in the San Francisco Bay area
who is willing to help me test the speakers I could use the help.

Thanks, JH


RMAA seems like it will fit your needs
http://audio.rightmark.org/index_new.shtml

assuming you have adequate sound cards, measurement mic, etc.

[Jim]

The more I read about this the more I wonder if I can get any useful
data running these test at home with a pc, even with a descent mic,
etc.

This is my problem: I built a pair of MTM 2 way speakers using a kit
from Zalytron. I bought a kit because I am a novice speaker builder at
best. I've never been able to test the speakers after I put them
together and I've always wondered if I am getting the optimum
performance out of them. I'd like to test them to get some sort of
objective "opinion" of their performance. Subjectively, they sound
very good to me but there is "something" missing.

I realize that testing them in my living room with a pc is not the best
condition but can I get some usable data? Of course, once I get the
data I need to know what to do with it. Maybe the speakers will be
just fine and its my ears that need tweeking (after all they are more
than 50 years old), but I wouldn't be surprised to find that the
crossovers need a bit of work.

So, if there is some kind sole out there who wouldn't mind giving me
the benefit of his or her vast knowledge, I would greatly appreciate
it.

Thanks, Jim
TimPerry wrote:
James Lehman wrote:
"Jim" wrote in message
oups.com...
Sorry if this is a repeat question, but I can't seem to find what
I'm looking for. I need a cheap, easy to use, but effective
software to test some speakers I've built. I need to test the
frequency response, the cross over, distortion, phase. . . that
sort of thing.

Can anyone recommend some software?

Better yet. . . if there is a member in the San Francisco Bay area
who is willing to help me test the speakers I could use the help.

Thanks, JH


RMAA seems like it will fit your needs
http://audio.rightmark.org/index_new.shtml

assuming you have adequate sound cards, measurement mic, etc.

[[email protected]]

Speaker Tests are usually done in an anechoic chamber. This is a room
on huge springs in another room and all the walls, incl floor and
ceiling are made of absorbing materials so that no reflections bounce
of them. They are completely silent (you'll hear your heart beat and
nervous system sing if you're in them and listen carefully) and try to
sound like an 'open field', that is to say, not sound at all. Perfect
anechoic chambers do not exist but are the closest you can come to
forming an 'objective' opinion about your speakers. Running tests at
home that involve playing sound over the speaker and using a
measurement mic to analyze its output are completely ridiculous for
they are very much influenced by acoustics. Stick to the multimeter and
just play music you know very well and judge their quality
subjectively. Even then there is a lot you can tell about their imaging
and freq response etc.
If you want to experience your room's acoustic coloration just connect
one speaker, play a sinesweep through it and listen to all the changes
in loudness; then realize that all the changes in loudness are
different for every position of the loudspeaker and the
listener/measurement mic. Loudspeaker placement is very important and
you can change its sound drastically. There are certain simple
guidelines for setting up speakers in a 'colored' room to get a nice
sound. Let me know it you want to hear.

regards Henk

[Arny Krueger]

"Jim" wrote in message
oups.com

Tim Perry wrote:

RMAA seems like it will fit your needs
http://audio.rightmark.org/index_new.shtml

assuming you have adequate sound cards, measurement mic, etc.


The more I read about this the more I wonder if I can get
any useful data running these test at home with a pc,
even with a descent mic, etc.

This is my problem: I built a pair of MTM 2 way speakers
using a kit from Zalytron. I bought a kit because I am a
novice speaker builder at best. I've never been able to
test the speakers after I put them together and I've
always wondered if I am getting the optimum performance
out of them. I'd like to test them to get some sort of
objective "opinion" of their performance. Subjectively,
they sound very good to me but there is "something"
missing.

I realize that testing them in my living room with a pc
is not the best condition but can I get some usable data?

Yes, by all means.

Of course, once I get the data I need to know what to do
with it.

Among other things the recommended Audio Rightmark program will provide a
frequency response curve generation facility. You need to look at both
on-axis and off-axis response.

There are lots of sites online that have posted frequency response test
results for speaker projects. Compare your speakers to them. Also, beg or
borrow comparable commercial speakers and test them.

IMO Tim Perry gave you really good advice. The Audio Rightmark program can
give you insights into your situation. This software uses a measurement
methodology that gives some immunity to irrelevant room effects.

To complete the test setup, you need a windows PC with a halfways-decent
audio interface, a mic preamp, and a measurement mic. The mic preamp can
be a cheap Behringer mixer such as the UB502 or Xenyx 502. The measurement
mic can be the inexpensive but widely-respected Behringer ECM 8000. A good
PC and $100 or so will set you up.

[[email protected]]

Jim wrote:
The more I read about this the more I wonder if I can get any useful
data running these test at home with a pc, even with a descent mic,
etc.

This is my problem: I built a pair of MTM 2 way speakers using a kit
from Zalytron. I bought a kit because I am a novice speaker builder at
best. I've never been able to test the speakers after I put them
together and I've always wondered if I am getting the optimum
performance out of them. I'd like to test them to get some sort of
objective "opinion" of their performance. Subjectively, they sound
very good to me but there is "something" missing.

I realize that testing them in my living room with a pc is not the best
condition but can I get some usable data? Of course, once I get the
data I need to know what to do with it. Maybe the speakers will be
just fine and its my ears that need tweeking (after all they are more
than 50 years old), but I wouldn't be surprised to find that the
crossovers need a bit of work.

I guess if you could show simulated results then measure and compare,
that would work out nicely.

While these all these other instruments are very valuable, one should
first start out by using pink noise and a basic spectrum analyzer.
Listening to pink noise is invaluable. It also trains you for things to
listen for. Listening to pink noise at all angles from the speaker is
also a necessary step. Comparison is also a good step. Use other
speakers for reference. After doing instrument testing one should go
back to the beginning and listen.

greg

[TimPerry]

Jim wrote:
The more I read about this the more I wonder if I can get any useful
data running these test at home with a pc, even with a descent mic,
etc.

This is my problem: I built a pair of MTM 2 way speakers using a kit
from Zalytron. I bought a kit because I am a novice speaker builder
at best. I've never been able to test the speakers after I put them
together and I've always wondered if I am getting the optimum
performance out of them. I'd like to test them to get some sort of
objective "opinion" of their performance. Subjectively, they sound
very good to me but there is "something" missing.

I realize that testing them in my living room with a pc is not the
best condition but can I get some usable data? Of course, once I get
the data I need to know what to do with it. Maybe the speakers will
be just fine and its my ears that need tweeking (after all they are
more than 50 years old), but I wouldn't be surprised to find that the
crossovers need a bit of work.

So, if there is some kind sole out there who wouldn't mind giving me
the benefit of his or her vast knowledge, I would greatly appreciate
it.

Thanks, Jim

based on the above i think the very best thing you could do is invest in or
build a stereo A/B switch (if your amp does not already have one.) you hook
you kit up to 'A' and you buddies speakers (which he paid megabucks for) to
'B'. then while consuming the beverages of your choice and listening to
you favorite tunes you THINK "wow my hand made speakers sound better then
his expensive boxes" while you SAY: "mine sounds pretty good to me but
yours sound way better"

then you do the same thing next week as HIS place only this time HE buys the
beverages.

you still may be confused as to exactly how good you speakers are but you
will have LOTS more fun.

[Arny Krueger]

"Jim" wrote in message
oups.com
Sorry if this is a repeat question, but I can't seem to
find what I'm looking for. I need a cheap, easy to use,
but effective software to test some speakers I've built.
I need to test the frequency response, the cross over,
distortion, phase. . . that sort of thing.

Can anyone recommend some software?

There's a simple and surprisingly effective loudspeaker test facility in
this free softwa

http://audio.rightmark.org/downloads...d-2.2-xram.exe

Eventually you might want something better, but experience with this
software will get you started.

[Rudi Fischer]

"Jim" wrote:

Sorry if this is a repeat question, but I can't seem to find what I'm
looking for. I need a cheap, easy to use, but effective software to
test some speakers I've built. I need to test the frequency response,
the cross over, distortion, phase. . . that sort of thing.

Can anyone recommend some software?

ARTA
http://www.fesb.hr/~mateljan/arta/index.htm

Rudi Fischer
--
....and may good music always be with you

[Jim]

Whoa . . . lots of great replies. Much to mull over. Since I don't
have access to a chamber I'll try the next best thing: some software
and a descent mic set up.

Thanks for the advise.
Jim

Rudi Fischer wrote:
"Jim" wrote:

Sorry if this is a repeat question, but I can't seem to find what I'm
looking for. I need a cheap, easy to use, but effective software to
test some speakers I've built. I need to test the frequency response,
the cross over, distortion, phase. . . that sort of thing.

Can anyone recommend some software?

ARTA
http://www.fesb.hr/~mateljan/arta/index.htm

Rudi Fischer
--
...and may good music always be with you

[[email protected]]

Jim wrote:
Whoa . . . lots of great replies. Much to mull over. Since I don't
have access to a chamber I'll try the next best thing: some software
and a descent mic set up.

Thanks for the advise.

That all being said, let me point out that as one who has spent
the last 30 or so years measuring hundreds and thousands of
loudspeakers in and out of chambers, using pretty much all of
the techniques outline here and more, that measuring loud-
speakers consistently, reliably and well is a VERY difficult task.

That's why, after reviewing all the replies, including my own,
I would recommend that you take some else's advice and
consider getting a pink noise source and a 1/3 octave real-
time analyzer. YOu can do it entirely in software on a PC
equipped with a decent microphone and soundcard using
John Murphy's TrueRTA (www.trueaudio.com). It's inexpensive
for the full-featured version, has settable bandwidth from 1/1
octave to 1/24 octave, and has a built in sine, sweep, white
and pink noise generator.

It;s not going to give you detailed phase information or
anything like that, but what would you do with it if you had
it?

Simple to use, reliabl;e, foolproof, and even though it's
a relatively low resolution tool, it avoids many of the pitfalls
of using far more sophisticated, far higher resolution, far
more difficult to use and interpret tools.