Author Topic: Speaker Cost vs Bass Performance  (Read 11108 times)

Offline _Scotty_

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Re: Speaker Cost vs Bass Performance
« Reply #45 on: February 14, 2018, 06:07:33 PM »
I think the key to good bass, beyond effectively controlling resonance problems below the rooms Schroeder frequency, is ensuring that the woofer accurately tracks and reproduces the incoming bass signal.
 A woofers intrinsic setting time or its rise and fall time only has to be the same or slightly faster than the incoming electrical waveform. It can't be as fast as drivers with lower moving mass and fortunately it doesn't have to be.
 
Unfortunately, I suspect that most of the time the woofers unassisted setting time may be slower than that of the electrical signal driving it, leading to a less than realistic reproduction bass instruments. This where servo control of the woofers signal tracking behavior, in particular, the ability to force the woofer to closely follow the bass waveforms decay characteristics through error correction, comes into its own. There really is no substitute for active control of the woofer, especially if listening to music with synthesizer bass content, which can exhibit bass waveform characteristics that are not subject to the physics that govern real world instruments, such as moving mass.
 
Obviously the dynamic driver based dipole subwoofer cannot function properly without the presence of servo control of the woofer.
I think quite satisfactory results could also be obtained from a boxed based subwoofer system in a room, albeit, at a greater cost when compared to a H-box based design.
Scotty

Offline steve

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Re: Speaker Cost vs Bass Performance
« Reply #46 on: February 14, 2018, 07:46:40 PM »
I think the key to good bass, beyond effectively controlling resonance problems below the rooms Schroeder frequency, is ensuring that the woofer accurately tracks and reproduces the incoming bass signal.
 A woofers intrinsic setting time or its rise and fall time only has to be the same or slightly faster than the incoming electrical waveform. It can't be as fast as drivers with lower moving mass and fortunately it doesn't have to be.
 
Unfortunately, I suspect that most of the time the woofers unassisted setting time may be slower than that of the electrical signal driving it, leading to a less than realistic reproduction bass instruments. This where servo control of the woofers signal tracking behavior, in particular, the ability to force the woofer to closely follow the bass waveforms decay characteristics through error correction, comes into its own. There really is no substitute for active control of the woofer, especially if listening to music with synthesizer bass content, which can exhibit bass waveform characteristics that are not subject to the physics that govern real world instruments, such as moving mass.
 
Obviously the dynamic driver based dipole subwoofer cannot function properly without the presence of servo control of the woofer.
I think quite satisfactory results could also be obtained from a boxed based subwoofer system in a room, albeit, at a greater cost when compared to a H-box based design.
Scotty

I agree if I understand you correctly Scotty. The problem is to keep the total Q about 0,7 or below, such that energy applied are absorbed via various means. This would include optimal losses due to electrical, mechanical of the driver, and the enclosure, whether open or closed.

Above ~0,7, then I agree some sort of feedback/servo control would be beneficial. The higher the total Q, the more energy not absorbed by suspension, box/materials, then the problem of "settling" time comes into play. Feedback would simulate a lower Q, thus beneficial.

The cost may not be higher at all, if the total Q of the entire speaker is optimized to absorb any excess energy, regardless of type, open, closed etc. That is why I suggest variable controls, at least one to adjust the total Q of the entire speaker. I do on mine, as Danny does, to optimize lower frequency accuracy.

All this helps in the seamless integration of woofer to mid and higher drivers.

cheers

steve
« Last Edit: February 14, 2018, 07:49:39 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
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Offline tmazz

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Re: Speaker Cost vs Bass Performance
« Reply #47 on: February 15, 2018, 08:51:42 AM »
Steve I understand andf xcan appriciate everything you said, but one thing is that most of us do not have your kind of talent or expeience and as such do not have access to the kind of hand tweaked eq

I understand and apologize if I come across in a poor way T, and others. Sometimes I feel that some ways of doing things get dumped on, when my own experiences say there is merit. I am also looking at what can be accomplished, pushing the borders of improvement.

cheers and no harm meant.

steve

Steve no apologies are necessary. (I should apologize for that mess of a post. I started to type something without reading it and then the phone rang and somehow I must have unintentionally hit the submit button. I'm kind of embarrassed that that mess ever made it onto the thread.)

You didn't come across in a poor way at all. The point that I was going to make, if I had finished the comment  :roll:, was that while what you were talking about is perfectly valid within the world of your equipment, most of us out here do not have access to equipment like yours. While Danny's subs might not be beneficial to you and your gear, they could be just the ticket for some of us out here that have to rely on commercially available gear which does not incorporate the technology that you have in your system.

I was not in any way trying to knock anything that you had said, just raise the point that Danny's can be the right product for certain folks in certain situations. (Just for the record, while I have heard his subs I could not own them as even his smaller model is too big for the space I have to work with.)

And BTW, as a fellow engineer, I rather enjoy reading your posts. My career took me in a direction other than audio so I do not have anywhere near the expertise you have in the field. But I do have enough knowledge to follow and understand what you are talking about and your posts take things down to a level of detail that I quite frankly never really thought about before and I find them quite interesting. Please keep them coming.
Remember, it's all about the music........

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Offline steve

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Re: Speaker Cost vs Bass Performance
« Reply #48 on: February 15, 2018, 01:26:07 PM »
Steve I understand andf xcan appriciate everything you said, but one thing is that most of us do not have your kind of talent or expeience and as such do not have access to the kind of hand tweaked eq

I understand and apologize if I come across in a poor way T, and others. Sometimes I feel that some ways of doing things get dumped on, when my own experiences say there is merit. I am also looking at what can be accomplished, pushing the borders of improvement.

cheers and no harm meant.

steve

Steve no apologies are necessary. (I should apologize for that mess of a post. I started to type something without reading it and then the phone rang and somehow I must have unintentionally hit the submit button. I'm kind of embarrassed that that mess ever made it onto the thread.)

You didn't come across in a poor way at all. The point that I was going to make, if I had finished the comment  :roll:, was that while what you were talking about is perfectly valid within the world of your equipment, most of us out here do not have access to equipment like yours. While Danny's subs might not be beneficial to you and your gear, they could be just the ticket for some of us out here that have to rely on commercially available gear which does not incorporate the technology that you have in your system.

I was not in any way trying to knock anything that you had said, just raise the point that Danny's can be the right product for certain folks in certain situations. (Just for the record, while I have heard his subs I could not own them as even his smaller model is too big for the space I have to work with.)

And BTW, as a fellow engineer, I rather enjoy reading your posts. My career took me in a direction other than audio so I do not have anywhere near the expertise you have in the field. But I do have enough knowledge to follow and understand what you are talking about and your posts take things down to a level of detail that I quite frankly never really thought about before and I find them quite interesting. Please keep them coming.

Thanks for your thoughtful reply T. I hope Danny does not think I was simply dicing his ideas, components etc. I am certain that most would certainly benefit from his expertise and products. I have heard great things about his products.

I certainly loved Danny's Myth of Speaker burn in webpage. It is that kind of research that moves the field forward.

Being in constant research mode certainly has its pluses, but also..... sometimes.  I hope my research will inspire others to expand their concepts in their search for optimal reproduction.

cheers

steve
« Last Edit: February 15, 2018, 01:35:38 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers

Offline tmazz

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Re: Speaker Cost vs Bass Performance
« Reply #49 on: February 15, 2018, 01:37:01 PM »
My wife would just shrug her shoulders and say it is just part of the disease of being an engineer.

We can never leave anything well enough alone. :-k

I have a friend who lives out in Colorado who tells me there is a psychologist in her town whose practice specializes in dealing with the wives of engineers and helping them learn to cope with all of out idiosyncrasies.   :rofl:

She is not one of his patients, but her husband is an engineer, so she appreciates the concept.  :roll:
Remember, it's all about the music........

• Nola Boxers
• Sunfire True SW Super Jr (2)
• McIntosh MC 275
• ARC SP-9
• VPI HW-19 Mk IV/SDS/SME IV/Soundsmith Carmen Mk II ES
• Pro-Ject Pre Box S2 DAC/Rasp Pi Roon Endpoint
• DigiBuss/TWL PC&USB/MIT Cables

Offline HAL

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Re: Speaker Cost vs Bass Performance
« Reply #50 on: February 15, 2018, 02:14:52 PM »
Been a EE for 38 years.  Has not changed one bit in the want to build stuff for repro of music.  Hence the 6x12 servo sub arrays and hybrid line arrays. 


Offline steve

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Re: Speaker Cost vs Bass Performance
« Reply #51 on: February 15, 2018, 08:53:47 PM »
My wife would just shrug her shoulders and say it is just part of the disease of being an engineer.

We can never leave anything well enough alone. :-k

I have a friend who lives out in Colorado who tells me there is a psychologist in her town whose practice specializes in dealing with the wives of engineers and helping them learn to cope with all of out idiosyncrasies.   :rofl:

She is not one of his patients, but her husband is an engineer, so she appreciates the concept.  :roll:

I got a chuckle with that T. I don't see any problem with us.  :rofl:

Dan, an audiophile, has helped out a lot. One time I told him of a tweak. His replay was

"NO! No more changes!"

Another time, though, I told him I think I am finished with tweaking. His reply was,

"No more changes? When pigs fly!"

What can we say T, it is in our DNA.  :thumb:

cheers

steve
 
« Last Edit: February 15, 2018, 09:05:47 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers

Offline tmazz

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Re: Speaker Cost vs Bass Performance
« Reply #52 on: February 15, 2018, 10:32:01 PM »

What can we say T, it is in our DNA.  :thumb:



Indeed it is.  8)

Check out Scott Adams thoughts on Engineering DNA:

https://www.youtube.com/watch?v=g8vHhgh6oM0
Remember, it's all about the music........

• Nola Boxers
• Sunfire True SW Super Jr (2)
• McIntosh MC 275
• ARC SP-9
• VPI HW-19 Mk IV/SDS/SME IV/Soundsmith Carmen Mk II ES
• Pro-Ject Pre Box S2 DAC/Rasp Pi Roon Endpoint
• DigiBuss/TWL PC&USB/MIT Cables

Offline _Scotty_

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Re: Speaker Cost vs Bass Performance
« Reply #53 on: February 16, 2018, 11:20:29 AM »
My wife knew what she was getting into when we were dating and married me anyway. :lol: While not an engineer I definitely have the problematic "DNA". The only time it really gets on her nerves is when I can't leave a recipe alone and make it as written, instead of tinkering with it. Everything else is fair game without too much grumbling. With few exceptions it seems like just about everything could stand some improvement, the trick is to recognize the exceptions when they crop up.
Something about "if it ain't broke don't fix it".
Scotty
« Last Edit: February 16, 2018, 11:25:08 AM by _Scotty_ »

Offline steve

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Re: Speaker Cost vs Bass Performance
« Reply #54 on: February 16, 2018, 03:22:05 PM »

What can we say T, it is in our DNA.  :thumb:



Indeed it is.  8)

Check out Scott Adams thoughts on Engineering DNA:

https://www.youtube.com/watch?v=g8vHhgh6oM0

My sides are aching, LOL. That is hilarious T.

Scotty, sounds like you have a great wife.

Just a clarification, Dan is not the Danny here.

cheers

steve
« Last Edit: February 16, 2018, 03:26:24 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers