1st attempt with BFD... your comments?

**highcurrent** · **05-05-06, 09:02 PM**

Hello fellow AV'ers,
I am in Charlotte NC and am an avid AV enthusiast. My room is HORRIBLE (want to get that out front). I have tried numerous peices of gear and am now working with Auralex on some acoustic treatments for my bonus-room-home-theater which is 21' long x 12' wide + a 6' wide window alcove on one side.

I am running a Def Tech PF15TL sub. I just bought a BFD and Rat Shack meter (just for ball park measurements) and made a few charts. I found the BFD very easy to set up and configure and easy to set the filters. However, the sound I get with the BFD engaged is just wrong. The BFD is doing something to the signal that is not right. Phase seems to be wrong and, well, the sub signal post-BFD sounds like poop. I have heard that the BFD has sub-par electronics (maybe that is why it is so cheap?) but I am going to give it a fair try.

The attached graph shows my first attempt with the BFD. Any and all comments are welcome...
Thanks-
HC

**brucek** · **05-05-06, 09:04 PM**

Quote:

The BFD is doing something to the signal that is not right

If you place the BFD in total bypass mode, does it sound OK?

You forgot to attach your graph.

brucek

**highcurrent** · **05-05-06, 09:12 PM**

Quote:

brucek wrote:

If you place the BFD in total bypass mode, does it sound OK?

You forgot to attach your graph.

brucek

Hi Brucek,
The graph should be there... I can see it.

In bypass mode it still doesn't sound as good as direct. I am using high-end cables too, on the unbalanced 1/4" inputs. I have heard of a lot of "pin 1" problems with the BFD on the balanced inputs causing a lot of noise, and RF buzz, 50-60Hz hum,... so I have not tried the balanced inputs yet.
Thanks

**Sonnie** · **05-05-06, 11:36 PM**

I would suspect with music that response should sound pretty good... you've flattened it out well. But for movies you may want to try a house curve.

There is a possibility that you may not be correcting some peaks that the 1/6 octave measurements will not show you. I don't know if it would make it sound that much worse though... but it's possible.

You may want to check out Room EQ Wizard (REW) and measure full resolution from 10-200hz.

Btw... welcome to the Shack!

**brucek** · **05-06-06, 11:44 AM**

Quote:

In bypass mode it still doesn't sound as good as direct.

It should sound exactly the same in bypass as it would without the BFD. Something is wrong with the hookup/cables or the BFD. You'll need to discover what that problem is before going any further in my opinion.

There are two types of bypass. One that bypasses the filters, and another bypass that is esscentially a pass through.

With the IN/OUT LED on steady, the filters are enabled.
With the IN/OUT LED off, the filters are bypassed.
With the IN/OUT LED flashing, the unit is bypassed.

In total bypass, you should notice absolutely no difference in your subs sound.

Quote:

I am using high-end cables too, on the unbalanced 1/4" inputs. I have heard of a lot of "pin 1" problems with the BFD on the balanced inputs causing a lot of noise, and RF buzz, 50-60Hz hum,... so I have not tried the balanced inputs yet.

The only problem I'm aware of is the ground loop problem causing hum. This is easily corrected. I have no experience with balanced or unbalanced problems.

Are you using standard phono to mono (not stereo) 1/4" jack plug adapters like this to connect to and from the BFD?

Are you turning all the filters 'OF' in the program on the BFD except where you are using a filter?

Have you set the input level to the BFD correctly?

brucek

**DrewM** · **05-06-06, 11:56 AM**

The first thing that comes to mind, given it sounds "poopy" in bypass mode, is that the phono plug adapter might be of the 1/4" to stereo variety instead of 1/4" to mono.

**Wayne A. Pflughaupt** · **05-06-06, 06:08 PM**

Keep us posted on what you find, highcurrent, but I’m going to hazard a guess that the problem is the virtually-ruler-flat curve. The fact is measured-flat response virtually never sounds good to most people. You might want to read up on the “House Curve” sticky thread.

Regards,
Wayne

**highcurrent** · **05-07-06, 02:55 PM**

Quote:

Sonnie wrote:

You may want to check out Room EQ Wizard (REW) and measure full resolution from 10-200hz.

Btw... welcome to the Shack!

Will check it out. Thanks

**highcurrent** · **05-07-06, 03:03 PM**

Quote:

brucek wrote:

Are you using standard phono to mono (not stereo) 1/4" jack plug adapters like this to connect to and from the BFD?

Are you turning all the filters 'OF' in the program on the BFD except where you are using a filter?

Have you set the input level to the BFD correctly?

brucek

Thanks for the reply and info. I am using mono 1/4" adapters just like the pic. I am going to try with XLR to see if there is any difference. There were some filters that were not OF and I have corrected that.

For the input level I followed the guide but I think I will reset everything, start over, and go through everything again from scratch to be sure everything is right.

Advertisement