which frequencies?

[dimmie]

Maybe I've made another mistake, because the "cut off" in the filter panel is at 80, this is the selected x-over right?....So it should be set at 100 for these readings?.......

dimitri

[brucek]

the "cut off" in the filter panel is at 80, this is the selected x-over right?....So it should be set at 100 for these readings?.......

Yes, it should be set at 100Hz in REW if the selected crossover in your receiver is set at 100Hz. This then displays and uses a 100Hz target for REW to adjust its filters.

Ensure your receiver is at 100Hz also...

brucek

[dimmie]

ok thanks again bruce.

I'll make 3 new measurements tomorrow, with the right setting in rew, at the three x-overs.

See what that does, I'm a bit worried about the -30 hz levels though....

We'll see tomorrow.

dimitri

[dimmie]

Well here they are.....

The measurement level had to be changed a bit, The amp is at +3 now.(instead of 0) so they look a bit different. Tell me what you think bruce!.

[brucek]

Well, they're all showing the same peaks and valleys - just extended crossover points. That's fine, but the reason to test multiple crossovers (before filtering) would presumably be to make a decision based on the capabilities of your mains.

To make this crossover decision, you need to connect the mains and do the exact same measurements over to see how the mains integrate at the different crossovers.

Once you've done that and decided on a crossover to use, then disconnect the mains and get on with the filtering process.....

brucek

[dimmie]

Ok, thanks bruce, I'll connect them and make the new measurements.

dimitri

p.s. When setting the input volume on the bfd, I only get 2 green led's. It won't go into the yellows and reds. Even when I turn up the lfe channel volume on the amp, is it possible that my amp doesn't produce enough bass. Would seem strange to me because it's a 110 watt amp....

[dimmie]

Ok, with the mains included....

[brucek]

When setting the input volume on the bfd, I only get 2 green led's

What signal are you sending the BFD to produce the 2 green LED's ?

Are you adjusting the subwoofer output trim level of your receiver to increase/decrease the level to the BFD ?

The standard procedure is to play a DVD like U571 and push the BFD IN/OUT switch to show "input level" in the LED's and then turn the receiver volume as loud as you would likely have it, and then adjust the receiver subwoofer output trim to see the Yellow LEDS come on in explosions etc...

is it possible that my amp doesn't produce enough bass. Would seem strange to me because it's a 110 watt amp....

Realize that the signal going to the BFD and then the subwoofer is a line level signal and has nothing to do with the power associated with the power amplifiers that feed the rest of the speakers in your system. The power associated with a subwoofer is derived from its own internal amplifier, not your receiver. The level from your receiver is controlled by the volume conntrol and the trim level.

brucek

[brucek]

Ok, with the mains included....

I would suggest using the 150Hz crossover. The mains appear to not be capable of extending low enough to support the 100hz cross.....

brucek

[dimmie]

brucek wrote:

What signal are you sending the BFD to produce the 2 green LED's ?

Are you adjusting the subwoofer output trim level of your receiver to increase/decrease the level to the BFD ?

The standard procedure is to play a DVD like U571 and push the BFD IN/OUT switch to show "input level" in the LED's and then turn the receiver volume as loud as you would likely have it, and then adjust the receiver subwoofer output trim to see the Yellow LEDS come on in explosions etc...



Realize that the signal going to the BFD and then the subwoofer is a line level signal and has nothing to do with the power associated with the power amplifiers that feed the rest of the speakers in your system. The power associated with a subwoofer is derived from its own internal amplifier, not your receiver. The level from your receiver is controlled by the volume conntrol and the trim level.

brucek

I have the lfe output set at minimum on the amp channel(-10) and I've got the sub gain set at about 10%, because I get excessive bass output really fast, due to the power of the monolith and the nature of my rooms response(I guess). If I want to even out the sub and mains I have to trim down the sub channel. This is probably the reasion the BFD is getting a weak signal. I also have a bass peak level manager on the amp, which controls the maximum amount of bass released by the amp. Which is set pretty rigidly also.

I just played a movie to check the led's reaction, attack of the clones, with some explosions. turned up the amp pretty high, with a maximum of 2 green led's.

I tried turning the lfe channel adjuster up to 0(and even higher), with no real improvement on the BFD.

Will a crossover of 150 hz. on the amp give me more power on the BFD?(stronger signal)?, because I tested on 100 hz. x.

Dimitri

[brucek]

I have the lfe output set at minimum on the amp channel(-10) and I've got the sub gain set at about 10%, because I get excessive bass output really fast,

Ignore the level of the subwoofer amplifier itself until you get the level of the receivers output to the BFD set. Simply turn up the LFE output and turn down the subwoofer amp. You need the input level to the BFD set first. Then bring up the level of the sub amp itself to suit..

Will a crossover of 150 hz. on the amp give me more power on the BFD?(stronger signal)?

The input to the BFD does not translate to power levels. It understands voltage levels. A higher crossover will provide more signal at the frequencies up to 150Hz, but not more level. If you need more level turn up the subwoofer output level on the receiver.

brucek

[dimmie]

brucek wrote:

Ignore the level of the subwoofer amplifier itself until you get the level of the receivers output to the BFD set. Simply turn up the LFE output and turn down the subwoofer amp. You need the input level to the BFD set first. Then bring up the level of the sub amp itself to suit..

Will a crossover of 150 hz. on the amp give me more power on the BFD?(stronger signal)?

The input to the BFD does not translate to power levels. It understands voltage levels. A higher crossover will provide more signal at the frequencies up to 150Hz, but not more level. If you need more level turn up the subwoofer output level on the receiver.)?

brucek

I'm away tomorrow and I'll be back sundaynight. maybe I'll report back to you on sunday.

have a nice weekend

[dimmie]

Was I supposed to use the correctional values for the radioshack meter?, I was under the impression that you only needed these for manual(non-REW) measurements. But they just came to mind.

I also realised that the amp I'm using(pioneer vsx-908/110 watts) has a bass peak manager utility. Which controls the maximum amount of bass that the amp delivers. So I connected the bfd in the chain and as I turned up the max. bass peak level on the amp, the green leds turned yellow and eventually red. Should I just turn it up all the way on the amp?. And let the BFD handle all the bass management?. Or should I allow it just to hit the red led?, and let the amp cut everything above that?.

[brucek]

Was I supposed to use the correctional values for the radioshack meter?,

Yes.

I also realised that the amp I'm using(pioneer vsx-908/110 watts) has a bass peak manager utility. Which controls the maximum amount of bass that the amp delivers.

Shut it off or set it at maximum level, and then set up the input level to the BFD as described in the BFD guide.

brucek

[dimmie]

I guess it's back to the drawing board. But it's ok. I'll put the bass peak at max. on the amp.

A friend of mine on the av forums told me I probably have a phase issue at the crossover piont, because I have a dip preceding and after the crossover. What's your opinion on that?, You can find the graphs a few posts back.

If there is a phase problem, Should it be handled now or after the sub is EQ'd?

[brucek]

You can find the graphs a few posts back

Are the graphs really valid since you didn't use a calibration file for the meter?

If there is a phase problem, Should it be handled now or after the sub is EQ'd?

As much as possible before, then eq the rest.

brucek

[dimmie]

brucek wrote:

Are the graphs really valid since you didn't use a calibration file for the meter?



As much as possible before, then eq the rest.

brucek

I'll take new measurements tomorrow with a calibrated spl meter. at the three x-overs. with the mains included. for a possible phase problem.

I already experimented by changing the sub distance in the receiver menu. at various setting. I'll do that again tomorrow. My initial setting turned out to be the best tonight, I'll see what happens tomorrow.

Dimitri

p.s. do you have to set a target level even when you've gone through the calibration procedure at startup?

[brucek]

do you have to set a target level even when you've gone through the calibration procedure at startup?

You need a target level to calculate filters

[dimmie]

I'll be measuring my sub alone first, and then team it up with my mains. and measure three x-overs. Should I recalibrate when I start using the mains also?. Or is the sub calibration sufficient for all measurements?, sub alone and sub+ mains?.

dimitri

[brucek]

Should I recalibrate when I start using the mains also?.

No, one calibration per session............

[dimmie]

Ok, here they are.

Sub alone/sub+mains 80 x/sub+mains 100 x/sub + mains 150 x.

What should I do next?, start creating filters for the sub?.

[brucek]

Well, it doesn't look like there is much difference between the three responses when I line them up?

Hopefully you actually changed the crossover in your receiver. If so, then I guess using 80Hz would be best.



Just read the sections in the help file on creating filters and also read this post and carry on.

brucek

[dimmie]

Hopefully you actually changed the crossover in your receiver

I know what you mean bruce, they look pretty much alike. But I did change it...

I actually programmed one filter just for the of it, and it worked pretty good. I'll post it tonight and I;ll get on to the other ones too.

dimitri

[dimmie]

I made some emasurements tonight, and noticed something strange.....

These have been taken right after eachother with the same settings.

Do you have an idea of what's happening bruce?

[brucek]

Do you have an idea of what's happening bruce?

No. Just ignore the anomoly and re-measure and then set your filters.