BFD 1124P and SMS-1 for Stereo Subs

**oris98** · **11-08-08, 05:46 AM**

Hi all,
I am new to bass manangement and I got myself one 1124P unit a few months ago. I after reading some of the threads here, Setting up 1124P can be lots of trouble and time consuming. I am thinking of getting a SMS-1 to run my stereo sub .

Can I use one SMS-1 room tune for one sub (one on my left and one on my right side alomost in the middle of the room close by the wall. While the second sub run by BDF ? Can I use SMS-1 to find out the frequency deficient between 20hz - 200hz and then manually set up the filter on the 1124p based on the freq. curve on SMS-1 and let bot bass managment tool work to gether ? So ultimately, both subs can be driven by one of its own EQ unit.

Thanks.

**brucek** · **11-08-08, 11:52 AM**

You're really going to extremes to avoid using REW software so you can set up a BFD properly.

The SMS will not offer the correct bandwidth, frequency and gain parameters that the BFD requires to set up its filters. That's what REW is designed to do.....

Certainly any filtering that the SMS applies to a sub in one location would be useless when applied to a sub in a different location.

brucek

**Wayne A. Pflughaupt** · **11-08-08, 12:26 PM**

Quote:

Can I use SMS-1 to find out the frequency deficient between 20hz - 200hz and then manually set up the filter on the 1124p based on the freq. curve on SMS-1 and let bot bass managment tool work to gether ?

brucek is right. Do you have REW up and running? If so, take a sweep and run the auto-EQ function using the 1124 as the equalizer of choice under the "Equalizer" tab. The EQ panel will tell you the exact values to enter into the 1124. Nothing could be easier.

Regards,
Wayne

**oris98** · **11-08-08, 06:54 PM**

I have not setup my 1124P yet. As I said, I am new to this, it is a bit intimidating in terms of setting it up the connection to the SBLive 24 and laptop and my Galaxy CM140. Comparing to the SMS-1, it is just plug and play solution. I haven't purchased the SMS-1 yet but I just want to understand if this is feasible to achieve what I want to do for bass management in a simplistic way. Also, I only have one 1124P now, can it actually handle 2 subwoofers running stereo ? or I still need a second 1124P for separate EQ for running it in stereo ? If I want to high pass the signal to my AMP so that it can cut 80hz and lower to my main amp for better clarity ? I am not sure this is a worthwhile practice. Will the electronics components of the 1124P good and transparently enough for serious 2 channel music ?
Do I need to apply any correction values of file for reading from my CM140 SPL meter ?

Thanks for the comment in advance..

**brucek** · **11-09-08, 09:04 AM**

Quote:

it is a bit intimidating in terms of setting it up the connection to the SBLive 24 and laptop and my Galaxy CM140

Hopefully, you have read and are completely familiar with REW Cabling Basics and the REW HELP files.

Quote:

Comparing to the SMS-1, it is just plug and play solution

What fun is that............... expensive too.

Quote:

just want to understand if this is feasible to achieve what I want to do for bass management in a simplistic way

No.

Quote:

I only have one 1124P now, can it actually handle 2 subwoofers running stereo ?

Yes. It's a two channel device with completely independant filters on each channel.

Quote:

If I want to high pass the signal to my AMP so that it can cut 80hz and lower to my main amp for better clarity ?

I don't understand the question. Can you rephrase it?

Quote:

Will the electronics components of the 1124P good and transparently enough for serious 2 channel music ?

On a subwoofer, yes. On mains, no.

Quote:

Do I need to apply any correction values of file for reading from my CM140 SPL meter ?

Yes. Again, I recommend first reading the REW HELP files.

brucek

**oris98** · **11-09-08, 06:58 PM**

Hi Burcek,

This generated me more interests to looking into setting up the 1124P for my setup. However, I am still confuse after first attempt reading the info. How can the computer measure the second room response curve after setting up the first EQ for my first sub say for left channel. I assume we need to measure the EQ curve with the presence of the left sub provide concurrent output with right channel ? This way, will get both EQ complementing both L and R channel together ? Any suggestion on how to setup stereo EQ ? Thanks again.

**brucek** · **11-09-08, 07:27 PM**

Quote:

Any suggestion on how to setup stereo EQ ?

The standard advice is to co-locate the two subs, and hopefully both those subs are identical or both enjoy the same response.

Those that attempt unique positioning of two subs differ on how best to equalize them. The usual method is to equalize each one standalone, and then test in concert to make final adjustments. Those that claim it best to equalize both at the same time will find the smoothed response plot can be confined to a small listening area.

brucek

**oris98** · **11-09-08, 07:37 PM**

" Co-locate the two subs" meaning put them side by side ? My two subs running stereo on each side of the room (L and R). I agreed to EQ one sub at a time for each ultimate location. However, I don't know how to further adjust them once they all run together ? There will be no indication like another response reading to show how both subs work together with running it own EQ setting. I am not sure the LF wave may colliding to each other and ended up cancelling each other without knowing the presence of the partner (the second sub) ??

Thanks.

**brucek** · **11-09-08, 07:43 PM**

Quote:

Co-locate the two subs" meaning put them side by side ?

Better to stack if possible, but side by side is the next best.

Quote:

There will be no indication like another response reading to show how both subs work together with running it own EQ setting.

Run REW sweep with both subs turned on. REW is a mono signal that you feed to the AUX or CD input of your receiver with a Y-adapter. The reciever is placed in stereo mode with all soundfields off and the mains disconnected.

brucek

**spearmint** · **11-16-08, 11:08 PM**

Quote:

brucek wrote:

The standard advice is to co-locate the two subs, and hopefully both those subs are identical or both enjoy the same response.

Those that attempt unique positioning of two subs differ on how best to equalize them. The usual method is to equalize each one standalone, and then test in concert to make final adjustments. Those that claim it best to equalize both at the same time will find the smoothed response plot can be confined to a small listening area.

brucek

This is how I've always setup my separated subs. EQ each individually then EQ as one. I use two subs for the LFE off my HT processor, and another two subs crossed over from my mains for 2ch. It works for me!

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