PDA

View Full Version : Flash: JBL Rookie Tries to set-up system



Chas
06-26-2004, 10:57 PM
Okay, here's the deal, my DIY 4333's have been reincarnated into a pseudo-S-22-1 set-up, 4505 cabinets (reinforced) w/(2231A, reconed as 2235/2440 re'phragmed as 2441-2311-2308/2405H). The whole shebang is (for now) is running with the Giskard 3-way (L300) voltage equivalent crossover and cut off at 100Hz@6 Db/octave.

Music is being reproduced in the listening room as opposed to merely sound....it's bloody wonderful...although I can't seem to get the lf/mf/hf balanced by ear. It kills me to admit this (after 30+ years in audio), to finally realize that maybe it's time to measure the room/speaker combination...there's too many variables here!

So, I welcome affordable opinions on pink noise sources and analysers...any thoughts, gang?

As soon as I can figure out how to post pictures of my lousy workmanship, I will do so. :p

Hofmannhp
06-27-2004, 02:01 AM
Originally posted by Chas
........
So, I welcome affordable opinions on pink noise sources and analysers...any thoughts, gang?...... :p

Hi Chas,

an easy , but not perfect solution for a raw measuring, is to use a FM-receiver for pink noise generation. But this can't be used for the frequency range down between 20 to 40 Hz and in the UHF range above 15kHz. Tune your FM with deactivated "muting" so you can hear the noise between the stations.....pink noise is available there.

This signal you can see with the help of your pc and the shareware "SpectraPlus" 30 days trial version as an analyzer.
You can directly connect the sound card input to a microphone (again....some missing quality through the mic and the soundcard)
but it works. (Spent money for this = 0,00 $)

HP

Figge
06-27-2004, 03:00 AM
Extremely intressting! how good results can one achieve with this method? have u tried it youself hp?

Hofmannhp
06-27-2004, 04:14 AM
Originally posted by Figge
Extremely intressting! how good results can one achieve with this method? have u tried it youself hp?

Hi Figge,

yes....I use this method sometimes in cause of beeing to lazy to assemble the big measuring stuff where the speakers are (the FM Tuner is always connected)
It's absolute ok to use it for the fine tuning of low-mid to high crossover points as also the main amplitude of the single driver ranges.

HP

Figge
06-27-2004, 04:18 AM
ok but i dont use active crossovers.. but i do have an old Eq lying around somewhere. i could use this method to try and get a flat respons with the eq and the l-pads on the speakers...right?

Chas
06-27-2004, 05:54 AM
Thanks for the great idea for a noise source HP, I was thinking about getting an RTA of some kind in order to make meaningful measurements. Any suggestions?

Robh3606
06-27-2004, 08:38 AM
Hello

Glad to see you having some fun!! I use test CD's as my pink noise source. Just drop it into the CD and play your track. I use the Delos HT set-up disk and also have a couple of the Stereophile disks about too. As far as an RTA??? You can do software like True RTA and others or go for a standalone like the Behringer 8024 which is actually quite a bit more than an RTA if you don't mind digitizing your source material. I don't know how often you are going to use it?? Can you borrow one?? Stand alone would cost more. If you went with software you would need a measurement microphone. I use the Behringer one but it needs phantom power so I have a battery box to supply that so I can go right into my sound card. Then just open up your software of choice and you should have what you need. Software does have advantages you can store samples look at the diferences between curves, look at 1/6 octave resolution ect. Depends on what you will be using it for.

http://www.trueaudio.com/

Rob:)