Problem with speaker connection

Popa · Apr 5, 2006, 07:20 PM

I have just recieved my new active monitors Dynaudio BM5a.
I have a problem with the connection between the soundard and the speakers. I've connected the spekaers directly to the soundcard, (no mixers, controlers, etc.). Every speaker has each own XLR input, so I had to plug one speaker in to the Analog FRONT and the other one in to the Analog REAR output. I can't connect them in no other way due to the cables. Except if I'd had a mixer, but it is not an option for now.
So, here comes the problem;

Something is wrong with the sound.
It seems like there are no low frequencies. (no bass)
But when I balance the sound (in Winamp, kX Mixer, etc.) only to the left or only to the right speaker, I get that punchy bass that the speakears should emmit in the first place.
Do you get what I mean?
--When the both monitors are playing, the sound is somehow lost. When I TURN OFF (plug the power out) from one of the speakers, the other speaker begins to emmit the full spectre.

Why this happens??
Could it be because AnalogFront are AC97 drivers, and the AnalogRear aren't ??

Or it could be that one of the line outputs on the soundcard is delayed a bit from the other (half of the millisecond or something), and therefore is causing the frequencies to bounce themselves in the air?

Tril · Apr 5, 2006, 11:17 PM

The XLR inputs on the speakers are analog balanced inputs. They can be used balanced or not. If used with a non balanced source, you must connect the unused speaker input pin to ground. You can use your soundcard as a balanced source by modifying the DSP.

Do you give each speaker a balanced signal by using a "phase" plugins in the DSP?

I'm thinking that your DSP is incorrectly set-up. You are probably sending the left and right signals to both speakers when you should be sending only the left signal to the left speaker and the right signal to the right speaker.

If you showed us your DSP and told us how exactly the soundcard is connected to the speakers, we could more easily tell you if your DSP is correct or not.

See this example of DSP : Balanced Output DSP

Popa · Apr 6, 2006, 07:54 PM

Hm.. Yes, I've just wanted to add the question what the PHASE plugin does. Because I've just tried to mess a little whth the dsp and discovered the PHASE thing. It seems that the problem is gone. But only seems. That's why I want to know what the Phase really does. I'm affraid of "sound change" even so if I can't hear it for now...
This is the picture of how did I set it up:

[img=http://www.picfury.com/d/snap2-6-th.jpg]

But when I connect both speakers trough the PHASE plugin like this;
[img=http://www.picfury.com/d/snap3-4-th.jpg]

, I get the same problem I had in the first place.
Is this right?
Are there any "sound changes" when I PHASE one output, and not the other?
Should I PHASE both speakers with each own PHASE plugin?
Thanks for the help...

Popa · Apr 6, 2006, 08:50 PM

And even if I DO phase both outputs with each own PHASE, again - I get the same problem..
hmmm...

Tril · Apr 6, 2006, 10:03 PM

The phase plugin multiply the signal by -1. It inverts the signal. It's the same as inverting the polarity on normal speakers.

If both speakers are connected the same, inverting one should not produce good sound.

Do you know if the cable grounds one of the speaker inputs or if it can be used with a balanced source?

Popa · May 28, 2006, 02:01 PM

The phase thing has definetley fixed the problem. Thank you for the help!

Tril · May 28, 2006, 09:40 PM

It's good to know that I was able to help.

Apr 5, 2006, 07:20 PM	#1
Popa HardwareHeaven Newbie Join Date: Apr 2006 Posts: 5 Rep Power: 0	Problem with speaker connection I have just recieved my new active monitors Dynaudio BM5a. I have a problem with the connection between the soundard and the speakers. I've connected the spekaers directly to the soundcard, (no mixers, controlers, etc.). Every speaker has each own XLR input, so I had to plug one speaker in to the Analog FRONT and the other one in to the Analog REAR output. I can't connect them in no other way due to the cables. Except if I'd had a mixer, but it is not an option for now. So, here comes the problem; Something is wrong with the sound. It seems like there are no low frequencies. (no bass) But when I balance the sound (in Winamp, kX Mixer, etc.) only to the left or only to the right speaker, I get that punchy bass that the speakears should emmit in the first place. Do you get what I mean? --When the both monitors are playing, the sound is somehow lost. When I TURN OFF (plug the power out) from one of the speakers, the other speaker begins to emmit the full spectre. Why this happens?? Could it be because AnalogFront are AC97 drivers, and the AnalogRear aren't ?? Or it could be that one of the line outputs on the soundcard is delayed a bit from the other (half of the millisecond or something), and therefore is causing the frequencies to bounce themselves in the air?

Apr 6, 2006, 07:54 PM	Thread Starter #3
Popa HardwareHeaven Newbie Join Date: Apr 2006 Posts: 5 Rep Power: 0	Hm.. Yes, I've just wanted to add the question what the PHASE plugin does. Because I've just tried to mess a little whth the dsp and discovered the PHASE thing. It seems that the problem is gone. But only seems. That's why I want to know what the Phase really does. I'm affraid of "sound change" even so if I can't hear it for now... This is the picture of how did I set it up: [img=http://www.picfury.com/d/snap2-6-th.jpg] But when I connect both speakers trough the PHASE plugin like this; [img=http://www.picfury.com/d/snap3-4-th.jpg] , I get the same problem I had in the first place. Is this right? Are there any "sound changes" when I PHASE one output, and not the other? Should I PHASE both speakers with each own PHASE plugin? Thanks for the help... Last edited by Popa; Apr 6, 2006 at 07:59 PM.

Apr 5, 2006, 11:17 PM	#2
Tril S-3D enthusiast Join Date: Sep 2004 Location: Canada Posts: 1,676 Rep Power: 64 System Specs	The XLR inputs on the speakers are analog balanced inputs. They can be used balanced or not. If used with a non balanced source, you must connect the unused speaker input pin to ground. You can use your soundcard as a balanced source by modifying the DSP. Do you give each speaker a balanced signal by using a "phase" plugins in the DSP? I'm thinking that your DSP is incorrectly set-up. You are probably sending the left and right signals to both speakers when you should be sending only the left signal to the left speaker and the right signal to the right speaker. If you showed us your DSP and told us how exactly the soundcard is connected to the speakers, we could more easily tell you if your DSP is correct or not. See this example of DSP : Balanced Output DSP

Apr 6, 2006, 08:50 PM	Thread Starter #4
Popa HardwareHeaven Newbie Join Date: Apr 2006 Posts: 5 Rep Power: 0	And even if I DO phase both outputs with each own PHASE, again - I get the same problem.. hmmm...

Apr 6, 2006, 10:03 PM	#5
Tril S-3D enthusiast Join Date: Sep 2004 Location: Canada Posts: 1,676 Rep Power: 64 System Specs	The phase plugin multiply the signal by -1. It inverts the signal. It's the same as inverting the polarity on normal speakers. If both speakers are connected the same, inverting one should not produce good sound. Do you know if the cable grounds one of the speaker inputs or if it can be used with a balanced source?

May 28, 2006, 02:01 PM	Thread Starter #6
Popa HardwareHeaven Newbie Join Date: Apr 2006 Posts: 5 Rep Power: 0	The phase thing has definetley fixed the problem. Thank you for the help!

May 28, 2006, 09:40 PM	#7
Tril S-3D enthusiast Join Date: Sep 2004 Location: Canada Posts: 1,676 Rep Power: 64 System Specs	It's good to know that I was able to help.