Your very own "Breaking in driver" CD

[Harley]

A little history first;

I followed the advise in the "Breaking in Drivers" thread where David ( via Bill ) listed out the steps for getting the where-with-all to cary out this exercise.

I copied the prescribed signal, burnt the 35 second long mp3 to disc and trundled off down to the factory to see how it would go.

Stuck the CD player on loop and I soon noticed that there's am awful lot of stops and starts with loud "spikes" that sound like disconnecting your bass lead without powering down first. Although these weren't huge, I thought well they can't be great for the driver - so plan D was called for.

I have a copy of Audacity - here's where you get if if you don't have it http://audacity.sourceforge.net/ - get the beta version, it works fine.

Next down-load the signal from the site David referred to http://binkster.net/extras.shtml#cd - pick the 31.5Hz mp3

Once you set Audacity up, you can record anything that plays on your computer....great if you're a muso and want to capture some live DVD stuff to examine those special riffs!

So play and record the signal all the way through - 30 seconds of it.

Make sure that the input signal is adjusted down on the (virtual ) VU meters so it does not distort.

You'll notice it has a loud "scratchy click" at the start and at the end.

You then cut out the start and the end to clean it up, and then highlight the clean bit, copy ( ctrl-C ) and go to the end and paste ( Ctrl - V )

That now gives you about say 40 seconds of clean signal. Keep repeating this process ( doubling up ) until you get a section of at least 1hr, 10 mins of clean recording IN ONE BLOCK. Then cut all the prevoius stuff so you are left with 70mins.

Save the file for safety and then File Export as an MP3

Burn that particular MP3 to disc and it will almost fill the disc up.

You now have a CD with 70 mins continuous clean signal without any spikes!

Harley

[vexorgtr]

I had fun with that CD in raw form playing it on my home stereo. My home sub I built a few years back does a mean 50hz, and an acceptable 31.5 Not bad for a single 10. It will be fun to try it on a tuba now that I've seen what a "DeathBox" will do. I've got the speaker bug... look out!

[DJ Big Ronn]

A little history first;

I followed the advise in the "Breaking in Drivers" thread where David ( via Bill ) listed out the steps for getting the where-with-all to cary out this exercise.

I copied the prescribed signal, burnt the 35 second long mp3 to disc and trundled off down to the factory to see how it would go.

Stuck the CD player on loop and I soon noticed that there's am awful lot of stops and starts with loud "spikes" that sound like disconnecting your bass lead without powering down first. Although these weren't huge, I thought well they can't be great for the driver - so plan D was called for.

I have a copy of Audacity - here's where you get if if you don't have it http://audacity.sourceforge.net/ - get the beta version, it works fine.

Next down-load the signal from the site David referred to http://binkster.net/extras.shtml#cd - pick the 31.5Hz mp3

Once you set Audacity up, you can record anything that plays on your computer....great if you're a muso and want to capture some live DVD stuff to examine those special riffs!

So play and record the signal all the way through - 30 seconds of it.

Make sure that the input signal is adjusted down on the (virtual ) VU meters so it does not distort.

You'll notice it has a loud "scratchy click" at the start and at the end.

You then cut out the start and the end to clean it up, and then highlight the clean bit, copy ( ctrl-C ) and go to the end and paste ( Ctrl - V )

That now gives you about say 40 seconds of clean signal. Keep repeating this process ( doubling up ) until you get a section of at least 1hr, 10 mins of clean recording IN ONE BLOCK. Then cut all the prevoius stuff so you are left with 70mins.

Save the file for safety and then File Export as an MP3

Burn that particular MP3 to disc and it will almost fill the disc up.

You now have a CD with 70 mins continuous clean signal without any spikes!

Harley

You know I was trying to think of a way to do that when it hit me. I have a Rokford Fosgate signal generator from my car audio days stashed in the shop. Senior moment guess! That's for that Harley, I'm sure a lot of people will get good use out of it.

[Harley]

... I'm sure a lot of people will get good use out of it.

Good to hear it may come in handy, thanks. The thought dawned on me this morning to get the computer to generate the signal and hook that up to the amp but I would not know how to go about that - I think it was a suggestion of Bill's some time ago.

I don't have a laptop either and so I'd need a big long lead.

Gosh that Audacity programme is great. I heard a nice bass riff on a jazz station on Showcast ( BFD member posted about this internet radio - great find ) so I just flicked on Audacity, recorded the bars I wanted at the turn arounds where the juicy bits were and now have something as a refernce point to start practicing up on. There are some very clever bassists out there...

[mk_drums]

i just used that rch tone generator thing and made a file and put it onto cd. it has a bit of a click but it wasnt too bad from memory

[MalcolmA]

Below is a Link to NCH Tone Generator which I think is what Mk_drums is referring to.

http://www.download.com/NCH-Tone-Genera ... ag=lst-0-1



At home I have Syntrillium Cooledit 2.0 (AKA Adobe Audition) A professional audio editing program, that is able to generate some pretty cool tones

It allows the user to set the length of the tone, and allows you to choose a particular start frequency and sweep right thru to to another freq of your choice. Eg One of the ones i often use goes from 400 hz - 20 hz over 60 seconds, (Quite handy for finding rattles etc in your living room, getting a rough idea of resonant frequencies in a room without expensive equipment etc)


Do we have anywhere here I could post some of these for the benefit of others??

Cheers
Malcolm

[hclague]

I use sigjenny it's a freeware tone generator that works great. Here is the link:

http://www.topshareware.com/SigJenny-download-5863.htm

Hal

[bgavin]

TrueRTA (www.trueaudio.com) is also a signal generator, plus a spendid realtime analyzer. The free version does great signal generation. I own the Level 4 version, with the tighest RTA resolution. Very comprehensive.

[Strapping Young Stu]

I regularly use the Cool Edit signal generator too and it generates all sorts of noise too, even the dreaded brown noise as I recall!

Theres also a tone generator in winISD www.linearteam.dk and I made up a nice set of tones in Cakewalk Sonar with it, moving up in semi-tone increments from 20Hz to about 400Hz which is about 40 different notes. It took ages, but its great if you are trying to figure out where room modes are affecting your mixes in the studio, I just play that back with an omni mic in the listening position and record the result.

You could probably adapt the same technique for EQ-ing PA but it would be dead slow.

Stu

[SoundInMotionDJ]

Sound Forge has a signal generator - Tools -> Synthesis -> Simple. You can generate any frequency for up to 60 seconds. A few cut-n-pastes later and you have what you need.

Audacity also has a tone generator - Generate -> Tone. It actually allowed me to input 3600 seconds, to get a full hour of the tone. But...it did take it a minute to complete that request.

Either result can be burned to CD for test purposes.

--Stan Graves

[bgavin]

The free version of TrueRTA turns on the signal generator and lets it run until you shut it off.

[nola50]

Since I'm new at breaking in speakers... I just set the speaker out of the box, connect to the amp, and run the signal for 24 hours at what voltage level? I want to break in a 3015LF. What about the midrange closed back one for the OT15B , does it need it ?

[Sydney]

at what voltage level?

Low... a couple of volts is fine.
In olden days, I kept it very simple... feed the driver some filtered between station noise, and leave for a while.
Nowadays you have many other options, including signal generators ( standalone or PC based - The WTII can also be used ) or a looped CD track.

What about the midrange closed back one for the OT15B , does it need it ?

I don't know if need is the right work - but all drivers are stiff initially, and loosen up with play.

[DAVID_L_PERRY]

Since I'm new at breaking in speakers... I just set the speaker out of the box, connect to the amp, and run the signal for 24 hours at what voltage level? I want to break in a 3015LF. What about the midrange closed back one for the OT15B , does it need it ?

Around 8-12 volts is what you should be using.

[WB]

What about the midrange closed back one for the OT15B , does it need it ?

I asked that once and the answer back was no.