A Few Questions

[android]

Hi, I've got a few beginner questions that I didn't find searching....

First, How do I know which crossover roll-off my amplifier uses? It is a Sony STR-V444ES, but the docs don't say. Only that it can be set in 10Hz increments when the main speakers are set to small.

Second, I don't get a subwoofer signal if my mains are off. Can I just unplug the speakers or is that bad for the receiver?

Thanks,
Andy

[brucek]

First, How do I know which crossover roll-off my amplifier uses?

It's not really essential information that you need. It likely conforms to the standard 4th order low pass and 2nd order high pass.

Second, I don't get a subwoofer signal if my mains are off. Can I just unplug the speakers or is that bad for the receiver?

Just unplug the mains at the receiver with the power off. No problems there, since it's solid state.

brucek

[Otto]

android wrote:

First, How do I know which crossover roll-off my amplifier uses?

Hi Andy,

As brucek said, it doesn't matter a whole lot, but if you really want to know, you can measure the response, as has been done here.

Good luck.

[android]

Thanks you guys. I'm getting measurements with the sub only. I've got big a 40Hz drop like I've seen posted here also.

[android]

Alright, so this is what I got. I had a big spike at 20Hz, but I used the PEQ in the sub to tone it down.

How terrible is this?

Also, after setting PEQ, the overall dB was lower, so I reset the sub level to match the mains with my setup DVD. Is this the right thing to do?

Thanks,
Andy

[brucek]

Is this the right thing to do?

Yep. The response is pretty **** good, but you should equalize down the peaks at ~50Hz and ~35Hz.

brucek

[Blaser]

I would then boost the dip at 39 Hz by 3 to 4 db, and the FR would be even better

[android]

I picked up a BFD today. From reading all the REW docs, I think I've figured out what to do, but I'm not exactly sure and I didn't find a start to finish procedure anywhere....

Is this what I should be doing?

1) hook up sound card -> BFD input 1 and BFD output 1 -> subwoofer input.
2) Open EQ menu in REW and select BFD as EQ to simulate.
3) Run test sweeps tweaking settings in REW EQ until response is how I want it.
4) Manually transfer settings from REW EQ page to BFD. (could use MIDI cable if I bought it, but I didn't) and hook receiver sub-woofer output to BFD input.
5) Enjoy!

Should I?

A) Do this once for my Dolby Digital 5.1 with LFE X-over set to 80Hz in the Receiver.
B) Do this again for my 5.1 direct analog in (SACD/DVD-Audio) with X-over set to 60Hz on the ICBM.

C) Or easier just to set 80Hz x-over on my ICBM and only EQ once?

I'm thinking I'd like the mains taking on a little more bass for music...

Thanks,
Andy

[brucek]

Hook the soundcard to the AUX or CD input of your receiver (with a Y-cable or two cables from REW soundcard), place the receiver in Stereo mode and set your desired crossover.

Do a sub only response first (with the mains speakers disconnected or turned off) - be sure power is off when you disconnect the mains....

Once the sub is equalized, hook up the mains and do another response and see how well they integrate with the sub at the crossover. Tweak if necessary.

No, you don't do it for DD 5.1 or any other mode. You're simply trying to set filters and flatten the subs response.

brucek

[Otto]

Sounds about right! Don't forget to calibrate your sound card and load your mic's/SPL meter's calibration file.

[android]

Otto wrote:

Sounds about right! Don't forget to calibrate your sound card and load your mic's/SPL meter's calibration file.

Yep, I already got .cal files going. I'll plot it tonight if the margheritas don't interfere with my technical skilz!