# B&W M-1 + ASW610 = frequency gap?



## BloomBloom (Feb 15, 2013)

Hello People,
Not sure if this is the right forum for this... If not please move the thread.

I have a new HT setup with 5 B&W M-1 satellites and a B&W ASW610 sub - all connected to a Yamaha RX-V673 amp.

The room is a bit funny so speaker placement isn't ideal (I'm sitting with my back to the wall so the surround speakers are parallel to the wall and not a bit behind the listening position).

Yesterday I had a friend come over to help me calibrate the system, he is a professional sound engineer and brought his kit...
Basically after trying all the speakers he identified a frequency gap between 60 - 100hz where the sub won't go higher than 60 (despite theoretically being able to reach 140Hz) and the satellites won't reach down bellow 100hz (despite being able to reach 64Hz according to B&W).

We literally played with the crossover frequency and there is no change between 60-100 because the speakers don't reach there... I left cross over at 100hz.

We balanced the system with an SPL meter and made sure the sub phase was correct. My mate added a couple of manual tweaks to the paraEQ so the system now sounds better than the auto setup or indeed, the 'no EQ' setting.

I wonder about the frequency gap... Surely B&W designed this system to blend in properly? The MT-50 package actually comes with the smaller ASW608...

What can I do to solve this? Is it a questions of speaker burn in? I've been using the system for about two weeks, for an hour or two a day, not at very high volumes... Will they improve frequency response over time?

Thanks!


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## AudiocRaver (Jun 6, 2012)

Speaker burn in, if it makes an audible difference at all, will never account for the gap you are experiencing.

Could you sketch us a rough picture of your listening room, furnishings, speaker positions?

How big is the speaker gap, how deep? Is it down 3 dB, 20 dB? How does it sound to you, can you hear the gap?


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## 8086 (Aug 4, 2009)

AudiocRaver said:


> Speaker burn in, if it makes an audible difference at all, will never account for the gap you are experiencing.
> 
> Could you sketch us a rough picture of your listening room, furnishings, speaker positions?
> 
> How big is the speaker gap, how deep? Is it down 3 dB, 20 dB? How does it sound to you, can you hear the gap?


http://www.innerfidelity.com/content/evidence-headphone-break


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## AudiocRaver (Jun 6, 2012)

8086 said:


> http://www.innerfidelity.com/content/evidence-headphone-break


Hey 8086, thanks for the link, I am a huge fan of Tyll Hertsens and his InnerFidelity site and his HeadFi work before that. Allow me to rephrase: _"Speaker burn in can make an audible difference, but those differences are generally small, often small enough to not be readily discernible. Even if it does make an audible difference with your system, it_ will never account for the gap you are experiencing _if it is indeed as drastic as you are describing._

Again I ask, how deep is the gap? You have stated it as being from 60 Hz to 100 Hz, which is wide, but the depth matters, too. It could be a shallow trough a few decibels deep, or it could be a deep notch, either would be audible but knowing more about it could help us determine what is causing it.:sn:


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## 8086 (Aug 4, 2009)

AudiocRaver said:


> Hey 8086, thanks for the link, I am a huge fan of Tyll Hertsens and his InnerFidelity site and his HeadFi work before that. Allow me to rephrase: _"Speaker burn in can make an audible difference, but those differences are generally small, often small enough to not be readily discernible. Even if it does make an audible difference with your system, it_ will never account for the gap you are experiencing _if it is indeed as drastic as you are describing._
> 
> Again I ask, how deep is the gap? You have stated it as being from 60 Hz to 100 Hz, which is wide, but the depth matters, too. It could be a shallow trough a few decibels deep, or it could be a deep notch, either would be audible but knowing more about it could help us determine what is causing it.:sn:


 Scott Wilkinson explains (on Leo Laporte radio) that when you buy new speakers, the materials is stuff. A hundred hours of play is enough to loosen them up and make things flexible so they can move around better. Some brands take longer than others. Some people play white or pink noise, while others run frequency sweeps, some just put their ipod or cd changer on and play the whole library, and others play only the _highest quality SACD_ on repeat for days on end. He also said (a while ago) that he thought the break-in material (program) didn't matter and just play what ever. 

Despite what some believe; it's just like a baseball glove, you only have one break in period and its done. 

I also agree that break in has nothing to do with the gap in sound he is experiencing. A break in wont make more bass or trebble.


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## BloomBloom (Feb 15, 2013)

Hi there,
I Dont have the exact details of my friends measurements. 
HOwveer, over the weekend I used an iPad app called Octave RTA (by Onyx) together with pink noise to test my system and it looks ok, please see the image below.

http://i.imgur.com/2U7WcpJ.png

The iPad mic isn't properly caliberated but I have to say it looks serious - I might get a better mic like the 
MicW i436 Omni iPhone/iPad Mic - has anyone had experience with both or can recomend a better app?

Also, based on my graph, assuming it is accurate, how can I furtehr tweak the paraEQ on the Amp? There are peaks around 50Hz and 180hz, what shoudl I do about them?

Thanks!


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## The Yeti (Jan 23, 2013)

Now that you've got the measurement bug, it's time for REW!


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## The Yeti (Jan 23, 2013)

According to your graph, that dip between 60-100hz ain't so bad, you look to be +/- 5db from about 40hz all the way to `500hz - *but *you need to take some real measurements with REW or OmniMic (something besides your iPad  ) so they can be compared to a known standard.


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## 8086 (Aug 4, 2009)

The Yeti said:


> Now that you've got the measurement bug, it's time for REW!


http://www.hometheatershack.com/forums/downloads-area/19-downloads-page.html


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## BloomBloom (Feb 15, 2013)

Thanks,
I gave REW a try but it's way to complicated for me...

I did get the MicW for the ipad and it looks like it's working very well.

Thanks!


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## 8086 (Aug 4, 2009)

BloomBloom said:


> Thanks,
> I gave REW a try but it's way to complicated for me...
> 
> I did get the MicW for the ipad and it looks like it's working very well.
> ...


Well, you need a USB microphone which is supported by REW. And don't worry about it being too complex, I am certain it is well with in your graps of understanding and learning. The forums are here to help you as you need it.


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## BloomBloom (Feb 15, 2013)

Thanks,
To the best of my understanding the ECM8000 isn't a USB mic, it requitres special cables and power...?

Is there a list or recomended USB mics?

Thanks!


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