I wish there was a cheap way... she is a foreign girl whom I took from remote village in Nepal at 5 and brought her up in Kathmandu so she could get an education and not be sold off or married young and stay ignorant and poor. Her mother and father cant read or write. Now she finished high school and wants to go to college and be EE. She is excellent in science, it turns out. Got immigration lawyer working on a visa for college near me. Will know in 1 week. Costing a small fortune...... i cant write it off taxes because she is not my daughter (but she thinks she is... sort of). And foreign students get to pay double.
She got 780 in SAT math. Max possible is 800. now she is bored waiting... 19 now ... so she is taking local college courses for no credit in Chemistry, Math, and Physics. Loves the stuff ! This is my best legacy... Sarada or as I call her - Sara.
Yes, i will soon be broke. But worth every penny. Got her out of poverty and she can help others do same. Then I can rest in peace. Did my part. My pay back.
-Richard
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A new book arrived today -- 20 April 2018 publication date.
Accurate Sound Reproduction Using DSP. by Mitch Barnett.
"This book provides the audio enthusiast with an easy to follow, step by step guide for designing a custom digital filter that corrects the frequency and timing response of your loudspeakers in your listening environment so that the music arriving at your ears matches as closely as possible to the content on the recording"
He credits another person for raising the bar on SOTA in Acoustic and Psychoacoustic Issues in Room Correction. James Johnston.
Thx-RNMarsh
Accurate Sound Reproduction Using DSP. by Mitch Barnett.
"This book provides the audio enthusiast with an easy to follow, step by step guide for designing a custom digital filter that corrects the frequency and timing response of your loudspeakers in your listening environment so that the music arriving at your ears matches as closely as possible to the content on the recording"
He credits another person for raising the bar on SOTA in Acoustic and Psychoacoustic Issues in Room Correction. James Johnston.
Thx-RNMarsh
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My Listening room is like Richards, only scaled down just a touch.
Speakers against the corners walls (Klipschorns) and fireplace. More open
than 45 degrees. Floor is brick, left wall is gypsum/plastered, right wall is
windows with drapes and mini blinds.
On the left wall is the largest tapestry I could find.
I dickered with the shop owner for hours in Prague
buying the hanging one in the back of his shop.
Now that I've seen them locally, I should have
bought a few more.
Large thick wool rug on the floor in the near field 14' x 10'.
It was thicker when I bought it, but the fuzz came off, now
its a tight wool pile.
Sofa is at the at the Near Far transition, approx
7/16s of the room length.
I should do another REW waterfall and see how it looks now.
I've got the Mastering Speakers almost ready to try out.
In the mean time back to work room Bench fixing up for me.
Cheers
Speakers against the corners walls (Klipschorns) and fireplace. More open
than 45 degrees. Floor is brick, left wall is gypsum/plastered, right wall is
windows with drapes and mini blinds.
On the left wall is the largest tapestry I could find.
I dickered with the shop owner for hours in Prague
buying the hanging one in the back of his shop.
Now that I've seen them locally, I should have
bought a few more.
Large thick wool rug on the floor in the near field 14' x 10'.
It was thicker when I bought it, but the fuzz came off, now
its a tight wool pile.
Sofa is at the at the Near Far transition, approx
7/16s of the room length.
I should do another REW waterfall and see how it looks now.
I've got the Mastering Speakers almost ready to try out.
In the mean time back to work room Bench fixing up for me.
Cheers
The whole thing has been wonderful. At 12, I started to bring her to Bangkok so she can see the potential of her education and learning to speak, read and write in English. See a modern city. Then I learned at restaurant, she did not know how to use a knife and fork. She had never used them... hands only. I said, OK... next year i take you here again and you practice. Sure enough, next time she was using fork and knife like a pro. Same issues with western toilet. Never used one before and didnt know how to use it. So many little things we take for granted. Hygiene. OMG. At 18 i am teaching her proper way to wipe herself so she doesnt get infections. What new surprises are in store for me when she is over here in 21st century country. But it is fun also. And, I have learned a lot from being on the inside of a very old and interesting culture. I could write a book on this adventure with her. She always tries her best and is a fast learner and wants to know about everything.
-RM
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Hi Richard,
Well, you completely changed her life. I have no doubt she returned and taught her new life skills to her family and some friends. You're helping a village, not just one person. I have no doubt that you are held in extremely high esteem there.
The gift of knowledge and the desire to improve is what you gave her. You know you helped, but perhaps not full extent of your generosity. Maybe you do. Either way, she literally owes you her life and this is not lost on her.
-Chris
Well, you completely changed her life. I have no doubt she returned and taught her new life skills to her family and some friends. You're helping a village, not just one person. I have no doubt that you are held in extremely high esteem there.
The gift of knowledge and the desire to improve is what you gave her. You know you helped, but perhaps not full extent of your generosity. Maybe you do. Either way, she literally owes you her life and this is not lost on her.
-Chris
It might be reasonable to discuss the history of time alignment of loudspeakers over the decades, and how important it is, (or not).
Back in the 1930's the only 'speaker alignment' that was promoted professionally was in movie theater horn loaded systems to remove any ECHO from a tap dancer's steps, and this was perhaps 8 milliseconds or so, or about 8 feet between the horn acoustic outputs. This seemed all that was necessary then, because over the previous century, the ear was modeled as monaurally phase def. This, at the time, was called: 'Ohm's Law of Acoustics' and it was considered a fundamental law of acoustics.
Then in about 1940, an engineer named Paul Klipsch, invented the Klipschorn, or the K-horn for short as a relatively compact 2-3 way full horn loudspeaker. The K-horn became the 'reference standard' for many decades, up to 1970 even. For example Richard Heyser had one in the '60's, as did I, and even Dave Wilson was moved into acoustics after listening to his first K-horn at a neighbors.
Well, what happened, and what was so good about this speaker? First, it was efficient (for a home system) at 104spl/W. This allowed virtually ideal triode amp drive that was the standard over those years. They not only could play loud, but they were 'effortless' sounding compared to direct radiators of the time, including the vaulted Acoustic Research acoustic suspension loudspeakers that were introduced in the mid-'50's.
However, when stereo came out, in the late '50's and '60's a problem came up with the K-horn. First, you needed two! Also you needed two decent corners, (a difficult find), and third, they would not 'image' very well, for some reason.
Then in 1968, Richard Heyser decided to attack the question of 'time delay' in speaker drivers, and he had the affront to say that perhaps even 2 ms (2 ft delay) between two drivers 'might' be audible in some circumstances. Immediately Paul Klipsch rose up at an AES meeting to object to Richard Heyser's statement.
Well, now, after 50 years, we know that Richard Heyser was right, and even too conservative in his estimation.
Yes, over the last 50 years, the belief that the ear is deaf to monaural phase is lost in history.
However, is 'speaker alignment' really the most obvious quality that is important? Not really, but it is more apparent now than in the past, but I listened to K-horns for 15 years, and I can still listen to the original pair that I owned, today, if I chose to, and I know that they keep my business partner happy, even today. Certainly a large step over typical inexpensive direct radiator speakers with music of any complexity.
Back in the 1930's the only 'speaker alignment' that was promoted professionally was in movie theater horn loaded systems to remove any ECHO from a tap dancer's steps, and this was perhaps 8 milliseconds or so, or about 8 feet between the horn acoustic outputs. This seemed all that was necessary then, because over the previous century, the ear was modeled as monaurally phase def. This, at the time, was called: 'Ohm's Law of Acoustics' and it was considered a fundamental law of acoustics.
Then in about 1940, an engineer named Paul Klipsch, invented the Klipschorn, or the K-horn for short as a relatively compact 2-3 way full horn loudspeaker. The K-horn became the 'reference standard' for many decades, up to 1970 even. For example Richard Heyser had one in the '60's, as did I, and even Dave Wilson was moved into acoustics after listening to his first K-horn at a neighbors.
Well, what happened, and what was so good about this speaker? First, it was efficient (for a home system) at 104spl/W. This allowed virtually ideal triode amp drive that was the standard over those years. They not only could play loud, but they were 'effortless' sounding compared to direct radiators of the time, including the vaulted Acoustic Research acoustic suspension loudspeakers that were introduced in the mid-'50's.
However, when stereo came out, in the late '50's and '60's a problem came up with the K-horn. First, you needed two! Also you needed two decent corners, (a difficult find), and third, they would not 'image' very well, for some reason.
Then in 1968, Richard Heyser decided to attack the question of 'time delay' in speaker drivers, and he had the affront to say that perhaps even 2 ms (2 ft delay) between two drivers 'might' be audible in some circumstances. Immediately Paul Klipsch rose up at an AES meeting to object to Richard Heyser's statement.
Well, now, after 50 years, we know that Richard Heyser was right, and even too conservative in his estimation.
Yes, over the last 50 years, the belief that the ear is deaf to monaural phase is lost in history.
However, is 'speaker alignment' really the most obvious quality that is important? Not really, but it is more apparent now than in the past, but I listened to K-horns for 15 years, and I can still listen to the original pair that I owned, today, if I chose to, and I know that they keep my business partner happy, even today. Certainly a large step over typical inexpensive direct radiator speakers with music of any complexity.
At the angle I'm listening there isn't that much of a null, the rear radiation shouldn't be absorbed with a dipole, it should be as similar as possible to the direct sound for it to work psychoacoustically. It's beneficial for it to be dispersed by the front wall. What would reversing the polarity do, I'll try it?
My experience with dipoles is that getting the reflection from the wall behind the speaker is a problem. If its delayed enough (10 feet between the speaker and the wall behind it) no problem. Otherwise many aspects are compromised. I use absorbers arrange to reflect obliquely so the rear sound takes a while to get to the listener.
RNM,
Long ago one of my friends born in Eastern Europe attended college here. First two years at community college, third year University of Pittsburgh and final year Carnegie-Mellon. Graduated with a prestigious EE degree at the lowest cost of anyone I ever knew. No need to mention his grades and recommendations. Died very young from a disease he caught before moving here that damaged his heart.
The advantage he got from starting at an easy college was that he could adapt in a less stressful situation. Also did most of his non-core requirements early.
Next step for you is to set up a bit of crowd funding for the lass. JC will kick in at least $10.00.
If that doesn't yield enough, eBay your accumulation of no longer used audio gear!
Long ago one of my friends born in Eastern Europe attended college here. First two years at community college, third year University of Pittsburgh and final year Carnegie-Mellon. Graduated with a prestigious EE degree at the lowest cost of anyone I ever knew. No need to mention his grades and recommendations. Died very young from a disease he caught before moving here that damaged his heart.
The advantage he got from starting at an easy college was that he could adapt in a less stressful situation. Also did most of his non-core requirements early.
Next step for you is to set up a bit of crowd funding for the lass. JC will kick in at least $10.00.
If that doesn't yield enough, eBay your accumulation of no longer used audio gear!
Citizenship is often required! As you acknowledge scholarships often cover tuition, some include housing, food, books and lab fees. Unless a stipend is attached weekends can get quite boring. But most leave everything but tuition still open.
Carnegie-Mellon when under a president from the business school ( Richard Cyert) realized that students applying to a college will have their decisions influenced by scholarships. So they put most of the scholarship money in grants for the first two years to attract high quality students. A few get the next two years but most then get loans. Effectively doubling the number of highly qualified students.
It took me a while to get it right regards positioning, and it's quite critical, I think it's probably because the room is quite small, dipoles on the whole aren't supposed to be too sensitive to position, I just haven't got ample space to play with. They seem to be doing all the things they're supposed to now.
Yes, it is. The key is to have left and Right signal at your ears to be exactly the same for best imaging. Localization applies to anything that is correlated to our ears. There is a test developed called Interaural Coherence Coefficient (IACC) to help with that. Its a measure of the acoustic L and R channel equality over time.
IACC10 -- "The sound arriving for the first 10 millisec should reach a value greater than 80% for good stereo imaging. Speakers with higher directivity, like horns or waveguides, tend to reach this value."
[Accurate Sound Reproduction Using DSP]
THx-RNMarsh
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Linkwitz says this about his room and the image :
"The two side walls are mostly double pane glass. The room is very long. A large brick fire place is 1.5 m (5 ft) behind the speakers. Imaging is very precise, given a good recording, with a smooth spread of the venue acoustics between the speakers and slightly beyond. The images are placed behind the plane of the speakers, never in front. The speakers disappear completely."
From here Frontiers
It seems the image I'm achieving is correct?
I dont know for sure..... if you have good imaging, it is because you have symmetry and equal time/distances. But you can measure and see how good it is or could be with IACC tests. Anyway, did you try my experiment... and what did you learn?
THx-RNMarsh
Back on speakers, has anyone other than Jan heard the Kii3 yet? Just mulling over the speaker discussions and thinking about compromises. I have neither space nor money for the M2s, I could have just afforded the smaller Gedlees had I been in the market when they were in production but for many in smaller houses the Kii might just be the optimum, if a bit pricey at $11500 and anti audiophile as you can't get in an fiddle with things.
If you are compromised further then where should you not compromise? If it's directivity then the synergy clones being done on here might just be the best thing for DIY in years.
If you are compromised further then where should you not compromise? If it's directivity then the synergy clones being done on here might just be the best thing for DIY in years.
That is pretty pricy all right. If you can afford that, then get the book by M.Barnett and software and do some tests... you might be able to make your own with great drivers and get accurate playback for a lot less.
I plan to use the PA portion of the Crown amps for my subs. Something like the miniDSP can help you get the cross-over portion dialed in for bi/tri-amping. But its those waveguides that wont be available and you need a way to control the directivity.
As a minimum we should start asking and requiring more complete data specs from the loudspeaker system makers.
THx-RNMarsh
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