Post by Aquaholic 2.0 on Apr 30, 2022 1:05:30 GMT
Does the forum not allow someone to cut and paste without citing the source? Seems unethical there. Also if you can translate this poat from HandInAss - congratulations.
What exactly is "lifelike" sound?
SandAndUnderagedAss:
What exactly is "lifelike" sound?
SandAndUnderagedAss:
Since we are on the subject of orchestra conductors, a few might recognize this one.
[IMG]
Leopold Stokowski at Carnegie Hall 1947 (public domain photo)
The following article was assembled from a publication on Jeff's Place, on PositiveFeedback.com.
The "Stokowski" Altec's were custom built loudspeakers for Dr. Leopold Stokowski (April 18, 1882 – September 13, 1977), during the time he lived in New York and was conducting the American Symphony Orchestra.
"Stokowski" Altec's
This page describes the current state of my "Stokowski" Altec loudspeakers based hifi system upon the conclusion of the Duelund-Altec Project article for Positive Feedback in October 2019 (HERE).
What you'll read here is an extract from that article, but updated to incorporate the system changes that have occurred over time since the Duelund-Altec Project article's publication, so as to reflect the current state of the system.
[IMG]
These vintage Altec loudspeakers are historically important vintage Altec loudspeakers that were custom made for the domestic use of conductor Leopold Stokowski in the early 1960s (hereinafter referred to as the "Stokowski" Altec's), that were updated with the latest state-of-art Duelund Coherent Audio CAST tinned-copper capacitors, inductors, and resistors in a Jean Hiraga inspired crossover circuit.
Let's first talk about the high-performance nature of these vintage Altec loudspeakers in and of themselves.
Most people don't usually connect the terms "vintage" with "high-performance," assuming instead that these two terms must be mutually exclusive. After all, don't the latest models of hifi offerings being produced for audio enthusiasts today represent the maximum attainable performance by leaps and bounds over the vintage equipment?
[IMG]
Peter Qvortrup of Audio Note UK.
Peter Qvortrup (Audio Note UK), certainly couldn't be accused of falling into the "most people" category on this topic, as I've discussed in blog posts at Jeff's Place related to my recent visit with Peter in Brighton, England.
Peter says that the peaks of high-performance developments in the recording and audio arts occurred early in audio and recording history, with the performance peak for recording quality and software quality occurring from approximately 1950 to 1960, the performance peak for amplification quality occurring from approximately 1920 to 1930, and the performance peak for loudspeaker quality occurring in the late 1930s, which was led by cinema sound research & development.
Peter also says since those peak performance periods in hi-fi history, as time has progressed we have seen diminishing returns in performance advancements, or even diminishment in overall performance, in the recording and audio arts.
So that's not to say that there isn't some truly great audio gear being produced today, there certainly is, but rather that the advancements in performance in gear being produced today are present in diminishing returns – and the magnitude of those advancements might not be as great as many enthusiasts perceive—compared to the peaks of performance that occurred historically.
I certainly share Peter's perceptions about the peak performance periods of the audio arts based on my own experiences with vintage hifi gear, or obviously I wouldn't have engaged in this project utilizing the ultra-high-performance Duelund CAST tinned-copper components in the vintage "Stokowski" Altec loudspeakers and written this article about it.
I think I would expand Peter's range for the performance peak of loudspeaker quality a wee bit, and suggest a range from the late 1930s to the early 1960s, although it could be argued that those advancements from the late 1930s to the early 1960s are largely refinements of what was done in the late 1930s.
Nevertheless, the main point is still that this period of time was a period when huge efforts and financial resources were being poured into advancing cinema sound performance through research & development by companies like Western Electric and Altec, as well as other cinema sound companies around the world, and represents the peak performance period in the history of loudspeaker research & development.
These custom Altec loudspeakers were built for conductor Leopold Stokowski for listening to music in his home and represent an apogee of sorts for that loudspeaker performance period, and incorporated the accumulated insights, knowledge, and technology development for that period.
Are the "Stokowski" Altec's still high-performance loudspeakers in today's terms?
I would say, yes, they are, and as a case in point, when my good friend Chad (2nd photo) was visiting me in September 2018, we set up the "Stokowski" Altec's in the positions normally reserved for my hot-rodded Tannoy Westminster Royal SE loudspeakers, which are an example of very high-performance loudspeakers with their external Duelund CAST crossovers.
After getting the Altec's in place, Chad said he thought the vintage "Stokowski" Altec's—even with their stock N-500-D Altec crossovers—actually exceeded the performance of my heavily modified and "Duelund-ized" Westminsters, and as I would find out in later listening sessions with other audio enthusiasts, that they were about equally split on preferring either the performance of the hot-rodded Westminsters or the custom vintage "Stokowski" Altec's.
My observations are that the Westminster's Dual Concentric drivers are more coherent, the high-frequency driver & horn combination are more resolving, and the Westminster's extend lower in the bass, but the vintage "Stokowski" Altec's have an edge in overall musicality, and a greater sense of live-like musical realism.
Finding out that these nearly six decades old custom vintage "Stokowski" Altec's could go pretty much toe-to-toe with my heavily hot-rodded Tannoy Westminster Royal SEs was certainly a wake-up call for me, and underscores the validity of what Peter has said about the peak of loudspeaker performance quality being led by cinema sound research & development by companies like Altec.
Now let me tie these custom Altec loudspeakers back to their original owner, the famous conductor, Leopold Stokowski, and fill in the gaps as to why that matters with respect to their performance.
It is fairly common knowledge that Leopold Stokowski was one of the world's leading conductors during his lifetime, and conducted numerous symphony orchestras, including of the Cincinnati Symphony Orchestra, the Houston Symphony Orchestra, the NBC Symphony Orchestra, the New York Philharmonic Symphony Orchestra, the Philadelphia Orchestra, and the Symphony of the Air, as well as others.
Leopold Stokowski was a remarkable and creative individual and musician, who was also very interested in the recording and reproduction of music, and had enormous influence upon the world of music, film, recording, audio engineering, and even culture, during his lifetime.
For example, Leopold Stokowski set American culture abuzz by hiring talented women and musicians of color for his orchestras during a time when orchestras were almost exclusively composed of white males.
His marriage to heiress and socialite Gloria Vanderbilt (above), set the media world abuzz about his high-profile relationships and celebrity lifestyle.
Another fascinating aspect of Leopold Stokowski's life—which is particularly relevant to his Altec loudspeakers—was that early in his career he became interested in the technical aspects of the recording and playback of music, something that most conductors of the time eschewed.
To aid Leopold Stokowski in his interests, Professor Charles Weyl at the University of Pennsylvania created a tailored curriculum for him that focused on what he needed to know about acoustics and electrical engineering in order to more effectively participate in guiding the technical activities of the audio engineering that he had become involved in.
The University of Pennsylvania eventually awarded Leopold Stokowski an honorary doctorate for his accomplishments in music, audio engineering, and film.
Leopold Stokowski worked closely with recording engineers during the acoustic horn recording era (1917-1924), the electrical recording era (1925-1940), and the "modern" analog recording era until his death (1941-1977), always striving for improved fidelity of recorded music. He heard it all.
Leopold Stokowski was very involved in advancing the recording and playback of music and worked closely with audio engineers from Altec Lansing, Bell Labs, Disney, RCA, and others, to advance the recording arts for records, film, and radio broadcast.
Leopold Stokowski loved experimenting with recording and playback technology and was involved in the development of multi-track recording used in some of the first stereo recordings.
He also collaborated with RCA in the use of a multi-track film recorder for the movie 100 Men and a Girl, in which Stokowski played a speaking part, and also with the Fantasound multichannel sound system developed by RCA and Disney engineers for the famous animated movie Fantasia.
So, have you ever wondered what a famous conductor like Dr. Leopold Stokowski—who was not only a brilliant conductor and musician, but was involved in every aspect of research and development advancements in film, recording, and the audio arts during their peak performance advancement periods—would build as his own ultimate loudspeakers for his personal home listening?
Well, you don't have to wonder, as you are looking at them in the above photo—the "Stokowski" Altec's.
The "Stokowski" Altec's are rather large loudspeakers (60 inches high by 30 inches wide by 26 inches deep), with Altec drivers, horns, and crossovers enclosed in truly massive custom wood cabinets, and fitted with burgundy grill cloth.
You can get an idea of the "Stokowski" Altec's size in the photo below where I am polishing them with some Kramer's Best Antique Improver prior to the start of the Duelund-Altec Project—they're even bigger than my Tannoy Westminster Royal SE loudspeakers!
[IMG]
The "Stokowski" Altec's were built very solidly and professionally, with everything fitted perfectly together.
These are vintage loudspeakers—they're almost six decades old now—and so their cabinets have accumulated a few scuffs and scrapes over the years, but still they are in very nice cosmetic condition considering their age, and the drivers, horns, crossovers and cabinets are in perfect operational condition—a testimony to the impeccable quality of Altec products of that period.
The cabinets that enclose the "Stokowski" Altec's provide substantial reinforcement for the 825-style bass horns that are incorporated into their cabinetry.
There is a divider panel between the low- and high-frequency horn sections of the cabinets—which would be an 825-style bass horn's top panel—that acts as a massive cross-brace to the cabinet's sidewalls.
The rear of the cabinet is broken into three segmented panels with further cross-bracing for the sidewalls, whereas the production 825 cabinet is a large, single, screw-mounted panel with no cross-bracing.
The heavily braced front panels are inset into the oversized sidewalls, so they too are acting as additional bracing, and the mounting panel for the 511B is also acting as yet another cross-brace.
All of that bracing and cabinetry adds up to a rigidity and massiveness for the "Stokowski" Altec cabinets that is off the charts compared to the regular production 825 bass horn cabinets like I have in my Altec A5 Voice of the Theatre loudspeakers.
The Stokowski Altec's components complement are 803B 16-Ohm bass drivers housed in the massively braced 825-style bass horn cabinets, Altec 804A 16-Ohm compression drivers that are mounted on Altec 511B horns and enclosed in their own dedicated high-frequency enclosure of the cabinets, and the Altec N-500-D crossovers are mounted inside the low-frequency cabinets.
[IMG]
The 803B low frequency driver is described in the Altec literature as, "The Altec 803B is a 15-inch low frequency loudspeaker of professional quality, chosen to complement the finest broadcast and recording studio monitor systems (such as the A7 and A7-500) in addition to providing the critical listener with superb bass reproduction for all wide-range public address, sound reinforcement and theatre or auditorium systems."
"Utilizing heavy Alnico V permanent magnets (2.4 lbs.), rugged, die-cast frames, edge-wound copper ribbon voice coils of the largest practical diameter (3"), and exceptionally compliant cone suspension, these LF transducers combine the advantages of long-term operation with unparalleled response throughout the entire audible bass frequency range (20-1,600 cycles)."
The Altec 803B low frequency driver has a continuous power rating of 30W, a frequency response of 20-1,600Hz, a sensitivity of 99dB (SPL at 4" from 1W), and 114dB (SPL at 4" from 30W).
The Altec 803B low frequency driver has an impedance of 16 Ohms, the cone resonance is 25 Hz, the Alnico V magnet flux density is 12,000 Gauss, the frame (basket) is structurally-reinforced cast aluminum, the cone is molded fiber, the cone suspension is a high-compliance cloth surround with mechanical resistance, the voice coil is edge-wound copper ribbon, the diameter is 15 1/8 inches (7" deep), and the weight is 17.5 pounds.
Up top are the Altec 804A 16-Ohm compression drivers mated to Altec 511-B horns (above).
The Altec 804A and Altec 802D compression drivers are essentially the same design, and are shown together in Altec literature.
The Altec 804A / 802D both use large diameter (1.75") aluminum ribbon edge-wound voice coils coupled to a large (2.25") aluminum diaphragm having tangential compliance. Both have a mechanical phasing plug with two exponential acoustic slots, which provides the proper phase relationship from sound emanating from the center & outer edges of the diaphragm and voice coil assembly, to give maximum high-frequency reproduction and a smooth overall response.
Like the 803B low frequency drivers, both the Altec 804A / 802D are rated for 30W. The Altec 804A / 802D frequency response is 500Hz to 22,000Hz, voice coil diameter is 1.75", impedance is 16 Ohms, and diameter is 4.5".
[IMG]
Leopold Stokowski at Carnegie Hall 1947 (public domain photo)
The following article was assembled from a publication on Jeff's Place, on PositiveFeedback.com.
The "Stokowski" Altec's were custom built loudspeakers for Dr. Leopold Stokowski (April 18, 1882 – September 13, 1977), during the time he lived in New York and was conducting the American Symphony Orchestra.
"Stokowski" Altec's
This page describes the current state of my "Stokowski" Altec loudspeakers based hifi system upon the conclusion of the Duelund-Altec Project article for Positive Feedback in October 2019 (HERE).
What you'll read here is an extract from that article, but updated to incorporate the system changes that have occurred over time since the Duelund-Altec Project article's publication, so as to reflect the current state of the system.
[IMG]
These vintage Altec loudspeakers are historically important vintage Altec loudspeakers that were custom made for the domestic use of conductor Leopold Stokowski in the early 1960s (hereinafter referred to as the "Stokowski" Altec's), that were updated with the latest state-of-art Duelund Coherent Audio CAST tinned-copper capacitors, inductors, and resistors in a Jean Hiraga inspired crossover circuit.
Let's first talk about the high-performance nature of these vintage Altec loudspeakers in and of themselves.
Most people don't usually connect the terms "vintage" with "high-performance," assuming instead that these two terms must be mutually exclusive. After all, don't the latest models of hifi offerings being produced for audio enthusiasts today represent the maximum attainable performance by leaps and bounds over the vintage equipment?
[IMG]
Peter Qvortrup of Audio Note UK.
Peter Qvortrup (Audio Note UK), certainly couldn't be accused of falling into the "most people" category on this topic, as I've discussed in blog posts at Jeff's Place related to my recent visit with Peter in Brighton, England.
Peter says that the peaks of high-performance developments in the recording and audio arts occurred early in audio and recording history, with the performance peak for recording quality and software quality occurring from approximately 1950 to 1960, the performance peak for amplification quality occurring from approximately 1920 to 1930, and the performance peak for loudspeaker quality occurring in the late 1930s, which was led by cinema sound research & development.
Peter also says since those peak performance periods in hi-fi history, as time has progressed we have seen diminishing returns in performance advancements, or even diminishment in overall performance, in the recording and audio arts.
So that's not to say that there isn't some truly great audio gear being produced today, there certainly is, but rather that the advancements in performance in gear being produced today are present in diminishing returns – and the magnitude of those advancements might not be as great as many enthusiasts perceive—compared to the peaks of performance that occurred historically.
I certainly share Peter's perceptions about the peak performance periods of the audio arts based on my own experiences with vintage hifi gear, or obviously I wouldn't have engaged in this project utilizing the ultra-high-performance Duelund CAST tinned-copper components in the vintage "Stokowski" Altec loudspeakers and written this article about it.
I think I would expand Peter's range for the performance peak of loudspeaker quality a wee bit, and suggest a range from the late 1930s to the early 1960s, although it could be argued that those advancements from the late 1930s to the early 1960s are largely refinements of what was done in the late 1930s.
Nevertheless, the main point is still that this period of time was a period when huge efforts and financial resources were being poured into advancing cinema sound performance through research & development by companies like Western Electric and Altec, as well as other cinema sound companies around the world, and represents the peak performance period in the history of loudspeaker research & development.
These custom Altec loudspeakers were built for conductor Leopold Stokowski for listening to music in his home and represent an apogee of sorts for that loudspeaker performance period, and incorporated the accumulated insights, knowledge, and technology development for that period.
Are the "Stokowski" Altec's still high-performance loudspeakers in today's terms?
I would say, yes, they are, and as a case in point, when my good friend Chad (2nd photo) was visiting me in September 2018, we set up the "Stokowski" Altec's in the positions normally reserved for my hot-rodded Tannoy Westminster Royal SE loudspeakers, which are an example of very high-performance loudspeakers with their external Duelund CAST crossovers.
After getting the Altec's in place, Chad said he thought the vintage "Stokowski" Altec's—even with their stock N-500-D Altec crossovers—actually exceeded the performance of my heavily modified and "Duelund-ized" Westminsters, and as I would find out in later listening sessions with other audio enthusiasts, that they were about equally split on preferring either the performance of the hot-rodded Westminsters or the custom vintage "Stokowski" Altec's.
My observations are that the Westminster's Dual Concentric drivers are more coherent, the high-frequency driver & horn combination are more resolving, and the Westminster's extend lower in the bass, but the vintage "Stokowski" Altec's have an edge in overall musicality, and a greater sense of live-like musical realism.
Finding out that these nearly six decades old custom vintage "Stokowski" Altec's could go pretty much toe-to-toe with my heavily hot-rodded Tannoy Westminster Royal SEs was certainly a wake-up call for me, and underscores the validity of what Peter has said about the peak of loudspeaker performance quality being led by cinema sound research & development by companies like Altec.
Now let me tie these custom Altec loudspeakers back to their original owner, the famous conductor, Leopold Stokowski, and fill in the gaps as to why that matters with respect to their performance.
It is fairly common knowledge that Leopold Stokowski was one of the world's leading conductors during his lifetime, and conducted numerous symphony orchestras, including of the Cincinnati Symphony Orchestra, the Houston Symphony Orchestra, the NBC Symphony Orchestra, the New York Philharmonic Symphony Orchestra, the Philadelphia Orchestra, and the Symphony of the Air, as well as others.
Leopold Stokowski was a remarkable and creative individual and musician, who was also very interested in the recording and reproduction of music, and had enormous influence upon the world of music, film, recording, audio engineering, and even culture, during his lifetime.
For example, Leopold Stokowski set American culture abuzz by hiring talented women and musicians of color for his orchestras during a time when orchestras were almost exclusively composed of white males.
His marriage to heiress and socialite Gloria Vanderbilt (above), set the media world abuzz about his high-profile relationships and celebrity lifestyle.
Another fascinating aspect of Leopold Stokowski's life—which is particularly relevant to his Altec loudspeakers—was that early in his career he became interested in the technical aspects of the recording and playback of music, something that most conductors of the time eschewed.
To aid Leopold Stokowski in his interests, Professor Charles Weyl at the University of Pennsylvania created a tailored curriculum for him that focused on what he needed to know about acoustics and electrical engineering in order to more effectively participate in guiding the technical activities of the audio engineering that he had become involved in.
The University of Pennsylvania eventually awarded Leopold Stokowski an honorary doctorate for his accomplishments in music, audio engineering, and film.
Leopold Stokowski worked closely with recording engineers during the acoustic horn recording era (1917-1924), the electrical recording era (1925-1940), and the "modern" analog recording era until his death (1941-1977), always striving for improved fidelity of recorded music. He heard it all.
Leopold Stokowski was very involved in advancing the recording and playback of music and worked closely with audio engineers from Altec Lansing, Bell Labs, Disney, RCA, and others, to advance the recording arts for records, film, and radio broadcast.
Leopold Stokowski loved experimenting with recording and playback technology and was involved in the development of multi-track recording used in some of the first stereo recordings.
He also collaborated with RCA in the use of a multi-track film recorder for the movie 100 Men and a Girl, in which Stokowski played a speaking part, and also with the Fantasound multichannel sound system developed by RCA and Disney engineers for the famous animated movie Fantasia.
So, have you ever wondered what a famous conductor like Dr. Leopold Stokowski—who was not only a brilliant conductor and musician, but was involved in every aspect of research and development advancements in film, recording, and the audio arts during their peak performance advancement periods—would build as his own ultimate loudspeakers for his personal home listening?
Well, you don't have to wonder, as you are looking at them in the above photo—the "Stokowski" Altec's.
The "Stokowski" Altec's are rather large loudspeakers (60 inches high by 30 inches wide by 26 inches deep), with Altec drivers, horns, and crossovers enclosed in truly massive custom wood cabinets, and fitted with burgundy grill cloth.
You can get an idea of the "Stokowski" Altec's size in the photo below where I am polishing them with some Kramer's Best Antique Improver prior to the start of the Duelund-Altec Project—they're even bigger than my Tannoy Westminster Royal SE loudspeakers!
[IMG]
The "Stokowski" Altec's were built very solidly and professionally, with everything fitted perfectly together.
These are vintage loudspeakers—they're almost six decades old now—and so their cabinets have accumulated a few scuffs and scrapes over the years, but still they are in very nice cosmetic condition considering their age, and the drivers, horns, crossovers and cabinets are in perfect operational condition—a testimony to the impeccable quality of Altec products of that period.
The cabinets that enclose the "Stokowski" Altec's provide substantial reinforcement for the 825-style bass horns that are incorporated into their cabinetry.
There is a divider panel between the low- and high-frequency horn sections of the cabinets—which would be an 825-style bass horn's top panel—that acts as a massive cross-brace to the cabinet's sidewalls.
The rear of the cabinet is broken into three segmented panels with further cross-bracing for the sidewalls, whereas the production 825 cabinet is a large, single, screw-mounted panel with no cross-bracing.
The heavily braced front panels are inset into the oversized sidewalls, so they too are acting as additional bracing, and the mounting panel for the 511B is also acting as yet another cross-brace.
All of that bracing and cabinetry adds up to a rigidity and massiveness for the "Stokowski" Altec cabinets that is off the charts compared to the regular production 825 bass horn cabinets like I have in my Altec A5 Voice of the Theatre loudspeakers.
The Stokowski Altec's components complement are 803B 16-Ohm bass drivers housed in the massively braced 825-style bass horn cabinets, Altec 804A 16-Ohm compression drivers that are mounted on Altec 511B horns and enclosed in their own dedicated high-frequency enclosure of the cabinets, and the Altec N-500-D crossovers are mounted inside the low-frequency cabinets.
[IMG]
The 803B low frequency driver is described in the Altec literature as, "The Altec 803B is a 15-inch low frequency loudspeaker of professional quality, chosen to complement the finest broadcast and recording studio monitor systems (such as the A7 and A7-500) in addition to providing the critical listener with superb bass reproduction for all wide-range public address, sound reinforcement and theatre or auditorium systems."
"Utilizing heavy Alnico V permanent magnets (2.4 lbs.), rugged, die-cast frames, edge-wound copper ribbon voice coils of the largest practical diameter (3"), and exceptionally compliant cone suspension, these LF transducers combine the advantages of long-term operation with unparalleled response throughout the entire audible bass frequency range (20-1,600 cycles)."
The Altec 803B low frequency driver has a continuous power rating of 30W, a frequency response of 20-1,600Hz, a sensitivity of 99dB (SPL at 4" from 1W), and 114dB (SPL at 4" from 30W).
The Altec 803B low frequency driver has an impedance of 16 Ohms, the cone resonance is 25 Hz, the Alnico V magnet flux density is 12,000 Gauss, the frame (basket) is structurally-reinforced cast aluminum, the cone is molded fiber, the cone suspension is a high-compliance cloth surround with mechanical resistance, the voice coil is edge-wound copper ribbon, the diameter is 15 1/8 inches (7" deep), and the weight is 17.5 pounds.
Up top are the Altec 804A 16-Ohm compression drivers mated to Altec 511-B horns (above).
The Altec 804A and Altec 802D compression drivers are essentially the same design, and are shown together in Altec literature.
The Altec 804A / 802D both use large diameter (1.75") aluminum ribbon edge-wound voice coils coupled to a large (2.25") aluminum diaphragm having tangential compliance. Both have a mechanical phasing plug with two exponential acoustic slots, which provides the proper phase relationship from sound emanating from the center & outer edges of the diaphragm and voice coil assembly, to give maximum high-frequency reproduction and a smooth overall response.
Like the 803B low frequency drivers, both the Altec 804A / 802D are rated for 30W. The Altec 804A / 802D frequency response is 500Hz to 22,000Hz, voice coil diameter is 1.75", impedance is 16 Ohms, and diameter is 4.5".