FR graph problem

tda · 14th January 2004, 12:41 PM

Guys,
I'm really stacked...Please read this thread http://diyaudio.com/forums/showthrea...threadid=25862
and give me any clue about what is happening. Nobody faced this kind of problem?

SY · 14th January 2004, 12:47 PM

I think a measurement of the impedance down below 200 Hz might be an appropriate step. It will let you really see what's going on with the box tuning. If you could post that, along with the raw driver's measured impedance curve, that might be useful.

I don't usually make language notes, but "I'm really stacked" has an unfortunate implication in English (at least in American English). Well, fortunate if you're a girl, unfortunate if you're not.

tda · 14th January 2004, 12:54 PM

So,
If I understand right, you tell me to measure the impedance driver mounted in the enclosure?
I have the impedance driver measured in free air, so I will post both of them today.
Sorry about my language, I'm doing my best.

SY · 14th January 2004, 12:59 PM

You do great in English- it's just that you've run into slang and idiom that I'm sure they don't teach in school!

Yes, you should absolutely look at impedance in the box. That will definitively tell you if your tuning is correct or not.

tda · 14th January 2004, 01:08 PM

Ok,
I will do this mesurement in a few hours and I will post it.
But I'm sure that the impdance curve will not look like the one in MathCAD sheets...

SY · 14th January 2004, 01:36 PM

Yes, but it will be diagnostic.

tda · 14th January 2004, 01:51 PM

Somebody wrote in my last thread that I should check the Cone excursion...but I didn't really understood what he want to say with this. What do you think?

SY · 14th January 2004, 02:38 PM

Well, first things first. Let's see if you've hit the target at the small-signal level.

What sort of volume (sound level) were you using for the frequency response measurements?

tda · 14th January 2004, 02:58 PM

I'm using Speaker Workshop for mesurements.
So I use my sound card for nearfield mesurements.

SY · 14th January 2004, 03:03 PM

One thing to be careful of is that you're actually measuring small-signal parameters. Keep the volume down.

14th January 2004, 12:41 PM	#1
tda diyAudio Member Join Date: Dec 2003 Location: Bucharest	FR graph problem Guys, I'm really stacked...Please read this thread http://diyaudio.com/forums/showthrea...threadid=25862 and give me any clue about what is happening. Nobody faced this kind of problem?

14th January 2004, 12:47 PM	#2
SY diyAudio Moderator Join Date: Oct 2002 Location: Austin, TX Blog Entries: 1	I think a measurement of the impedance down below 200 Hz might be an appropriate step. It will let you really see what's going on with the box tuning. If you could post that, along with the raw driver's measured impedance curve, that might be useful. I don't usually make language notes, but "I'm really stacked" has an unfortunate implication in English (at least in American English). Well, fortunate if you're a girl, unfortunate if you're not. __________________ “Listening to records is like ****ing a picture of Brigitte Bardot.” - Sergiu Celibidache

14th January 2004, 12:59 PM	#4
SY diyAudio Moderator Join Date: Oct 2002 Location: Austin, TX Blog Entries: 1	You do great in English- it's just that you've run into slang and idiom that I'm sure they don't teach in school! Yes, you should absolutely look at impedance in the box. That will definitively tell you if your tuning is correct or not. __________________ “Listening to records is like ****ing a picture of Brigitte Bardot.” - Sergiu Celibidache

14th January 2004, 01:36 PM	#6
SY diyAudio Moderator Join Date: Oct 2002 Location: Austin, TX Blog Entries: 1	Yes, but it will be diagnostic. __________________ “Listening to records is like ****ing a picture of Brigitte Bardot.” - Sergiu Celibidache

14th January 2004, 02:38 PM	#8
SY diyAudio Moderator Join Date: Oct 2002 Location: Austin, TX Blog Entries: 1	Well, first things first. Let's see if you've hit the target at the small-signal level. What sort of volume (sound level) were you using for the frequency response measurements? __________________ “Listening to records is like ****ing a picture of Brigitte Bardot.” - Sergiu Celibidache


	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

14th January 2004, 12:54 PM	#3
tda diyAudio Member Join Date: Dec 2003 Location: Bucharest	So, If I understand right, you tell me to measure the impedance driver mounted in the enclosure? I have the impedance driver measured in free air, so I will post both of them today. Sorry about my language, I'm doing my best.

14th January 2004, 01:08 PM	#5
tda diyAudio Member Join Date: Dec 2003 Location: Bucharest	Ok, I will do this mesurement in a few hours and I will post it. But I'm sure that the impdance curve will not look like the one in MathCAD sheets...

14th January 2004, 01:51 PM	#7
tda diyAudio Member Join Date: Dec 2003 Location: Bucharest	Somebody wrote in my last thread that I should check the Cone excursion...but I didn't really understood what he want to say with this. What do you think?

14th January 2004, 02:58 PM	#9
tda diyAudio Member Join Date: Dec 2003 Location: Bucharest	I'm using Speaker Workshop for mesurements. So I use my sound card for nearfield mesurements.

14th January 2004, 03:03 PM	#10
SY diyAudio Moderator Join Date: Oct 2002 Location: Austin, TX Blog Entries: 1	One thing to be careful of is that you're actually measuring small-signal parameters. Keep the volume down. __________________ “Listening to records is like ****ing a picture of Brigitte Bardot.” - Sergiu Celibidache

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
looking for FR graph for w3-871	kifeinthesink	Multi-Way	6	7th June 2008 07:15 AM
what is an FFT graph?	keantoken	Everything Else	23	10th September 2006 12:13 AM
Graph shapes	Danielb	Multi-Way	9	3rd November 2004 12:26 AM
What graph to look at?	pjacobi	Solid State	3	18th February 2004 01:56 AM
help interpreting graph	getafix	Multi-Way	6	12th October 2003 12:52 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read