Newbie to REW and BFDs....need phone support

**Mattlock** · **12-24-07, 01:14 AM**

I just completed by sonosub build (700 liters), FiCAR Q18, tuned to 13hz, powered by EP2500 (bridged mono) along with BFD1124.

As a newbie I am learning slowly but surely but here's my current status/situation...

I've taken some manual readings with my Digital RPL meter but several people have told me that I really need to use the REW software. So I went out and purchased the Creative USB Live Soundcard to hook up to my laptop.

I've been reading the Help Guides but quite frankly I'd like someone to walk me through it. Would anyone be willing to walk me through this software and how to use it over the phone?

Never hurts to ask....right?

thanks
Matt

**Otto** · **12-24-07, 08:03 AM**

I might actually be willing to do something like that...

Where are you with it right now? Do you have the PC connected to the receiver/preamp? That's the first step. Get REW installed and physicallly connected to the PC, so that it can do a sweep. You will take the line-out of the soundcard, using a stereo cable, to an analog input on your receiver. At that point, you should be able to generate "sounds" to your system via your PC.

Also, connect the SPL meter to the "line-in" (don't use "mic-in") of the soundcard. You will use a stereo plug to the soundcard, and it will have to break out to left and right. You will insert the SPL meter to one side of that (REW defaults to left, so just go in left). At that point, you should be able to measure sounds coming in the mic of the SPL meter (e.g., if you have the "SPL Meter" up on REW, it will jump if you clap your hands in front of the SPL meter).

Let's see if we can get that far, and then see what happens.

I don't suppose you're in Colorado?

**Mattlock** · **12-24-07, 10:22 AM**

Quote:

Otto wrote:

I might actually be willing to do something like that...

Where are you with it right now? Do you have the PC connected to the receiver/preamp? That's the first step. Get REW installed and physicallly connected to the PC, so that it can do a sweep. You will take the line-out of the soundcard, using a stereo cable, to an analog input on your receiver. At that point, you should be able to generate "sounds" to your system via your PC.

Also, connect the SPL meter to the "line-in" (don't use "mic-in") of the soundcard. You will use a stereo plug to the soundcard, and it will have to break out to left and right. You will insert the SPL meter to one side of that (REW defaults to left, so just go in left). At that point, you should be able to measure sounds coming in the mic of the SPL meter (e.g., if you have the "SPL Meter" up on REW, it will jump if you clap your hands in front of the SPL meter).

Let's see if we can get that far, and then see what happens.

I don't suppose you're in Colorado?

thanks Otto. I need to get a converter to connect my RCAs to my soundcard. Apparently the card takes smaller (1/8 ?) size inputs.

Question.. my soundcard as several "outs" SPDIF=Out (RCA) Left, right, Center, SW, (these are smaller 1/8s it appears). Which out should I use to my BFD?

thanks

**Mattlock** · **12-25-07, 07:52 PM**

Quote:

Otto wrote:

I might actually be willing to do something like that...

Where are you with it right now? Do you have the PC connected to the receiver/preamp? That's the first step. Get REW installed and physicallly connected to the PC, so that it can do a sweep. You will take the line-out of the soundcard, using a stereo cable, to an analog input on your receiver. At that point, you should be able to generate "sounds" to your system via your PC.

Also, connect the SPL meter to the "line-in" (don't use "mic-in") of the soundcard. You will use a stereo plug to the soundcard, and it will have to break out to left and right. You will insert the SPL meter to one side of that (REW defaults to left, so just go in left). At that point, you should be able to measure sounds coming in the mic of the SPL meter (e.g., if you have the "SPL Meter" up on REW, it will jump if you clap your hands in front of the SPL meter).

Let's see if we can get that far, and then see what happens.

I don't suppose you're in Colorado?

Otto,
I got as far as you suggested (handclapping) but I am having a problems with the "line out" to my BFD.

I have several "outs"....SPDIF, Right, Left, Center and S/W.

Which should I be using as my "out" (to the BFD)?

**Otto** · **12-25-07, 09:57 PM**

Hey Matt,

Sorry, I must have missed your post yesterday; not sure why...

I would guess that the left/right will be a stereo combo on a single 1/8" jack. Use that one (with a stereo 1/8" to L/R RCA cable) to an analog stereo input of your receiver (though you will only use the left, most likely). From there, you should be able to generate a signal to the receiver. You can do a sweep or use the tone generator in REW to see if you can hear something. Keep the volume down at first. I might suggest starting with a 500 Hz tone (sine wave) from the generator. Slowly increase the volume on your receiver until you can hear something.

From there, we'll do a soundcard cal and some input/output level cals, and you'll be ready to sweep! I still might be able to help on the phone, but you know how time is tight. My wife already thinks I spend too much time here (I do!), and she'll think I'm really nuts if I go to the next level!

Oh, I just noticed that you said this:

Quote:

Which should I be using as my "out" (to the BFD)?

I know I noted it above, but that "out" is going to the receiver or preamp, not the BFD.

Good luck!

Also, did you ever get the EP2500 to sub thing resolved?

**Mattlock** · **12-25-07, 10:53 PM**

Quote:

Otto wrote:

Hey Matt,

Sorry, I must have missed your post yesterday; not sure why...

I would guess that the left/right will be a stereo combo on a single 1/8" jack. Use that one (with a stereo 1/8" to L/R RCA cable) to an analog stereo input of your receiver (though you will only use the left, most likely). From there, you should be able to generate a signal to the receiver. You can do a sweep or use the tone generator in REW to see if you can hear something. Keep the volume down at first. I might suggest starting with a 500 Hz tone (sine wave) from the generator. Slowly increase the volume on your receiver until you can hear something.

From there, we'll do a soundcard cal and some input/output level cals, and you'll be ready to sweep! I still might be able to help on the phone, but you know how time is tight. My wife already thinks I spend too much time here (I do!), and she'll think I'm really nuts if I go to the next level!

Oh, I just noticed that you said this:

I know I noted it above, but that "out" is going to the receiver or preamp, not the BFD.

Good luck!

Also, did you ever get the EP2500 to sub thing resolved?

Yes got the EP2500 to sub resolved.

Based on my read of the REW help guide, it suggests that to Calibrate the Soundcard I should connect directly from Input to OUtput(of the soundcard)....problem is I am not getting a good test... I get a message that "the highest measurement is -87db which is too low and I should check my inputs/volume/etc. It say it is probably a feedback loop....I checked to make sure my "monitor button" isnt checked but can't figure out what else to do.....

Also, it does say for testing the Sub alone that I should connect directly to the BFD...Is this correct? I know that going directly to the receiver will test all speakers but first I wanted to just work on the sub....then I'll go to the receiver...make sense?

**Otto** · **12-26-07, 08:50 AM**

Not sure about the loopback thing. Have you been able to get a sound out of the soundcard to the receiver yet? If so, that's on indication that you are generating sounds. If you can clap and read a sound on REW, then you can receive sounds. You need those two pieces to do a soundcard cal. How do you have the soundcard hooked to itself? It should be a stereo to stereo 1/8" cable, going from the output to the input (in your case, probably "L/R front out" to "line-in"). Are volumes up all the way on the audio control for Windows?

I guess you could connect directly to the BFD, but most go straight to the receiver, which will feed the sub. I've always gone that direction.

**Mattlock** · **12-26-07, 03:43 PM**

Quote:

Otto wrote:

Not sure about the loopback thing. Have you been able to get a sound out of the soundcard to the receiver yet? If so, that's on indication that you are generating sounds. If you can clap and read a sound on REW, then you can receive sounds. You need those two pieces to do a soundcard cal. How do you have the soundcard hooked to itself? It should be a stereo to stereo 1/8" cable, going from the output to the input (in your case, probably "L/R front out" to "line-in"). Are volumes up all the way on the audio control for Windows?

I guess you could connect directly to the BFD, but most go straight to the receiver, which will feed the sub. I've always gone that direction.

The out I was using was the S/W out on the soundcard but quite frankly I tried all of the outs and could not get a signal ....even though I doubt it I may need to try another soundcard....volumes are up but i will double check. I'll try going directly to receiver next.

will play around some more....

thanks

**Otto** · **12-26-07, 05:32 PM**

Yeah, not sure what REW will do with the SW out. It might get confused.

Can you play music through the system when using the L/R outs?

**Mattlock** · **12-26-07, 10:57 PM**

Quote:

Otto wrote:

Yeah, not sure what REW will do with the SW out. It might get confused.

Can you play music through the system when using the L/R outs?

I did finally get my soundcard calibrated but I still cannot get any audible output when running through my receiver (or BFD (sub only). The soundcard is sending the signal (per the REW meter) but not sound yet....

**Otto** · **12-27-07, 08:45 AM**

You're using a stereo 1/8" cable out the L/R to an RCA breakout that goes to the receiver's analog input, right? Is it possible that that input's been assigned to a digital input from previous use?

**Mattlock** · **12-27-07, 12:15 PM**

Quote:

Otto wrote:

You're using a stereo 1/8" cable out the L/R to an RCA breakout that goes to the receiver's analog input, right? Is it possible that that input's been assigned to a digital input from previous use?

Problem was resolved..I used the headphones out and that worked perfectly. Done my sweeps and trying to get filters set now....

I'll post some graphs soon

thanks Otto

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