Time-aligned speakers- who builds them?
- Thread starter thedelihaus
- Start date
Perhaps somewhat interesting ... Radio Shack produced a time aligned model - the Realistic Optimus 80 starting in 1983. See http://www.radioshackcatalogs.com/ and attached.
Attachments
That is a neat trick and VERY few speakers can push a square wave that can been recognized on a scope trace
Susurus
Resolution:6.62×10^-34
Magnat Magnesphere
Fulton Modulars
Alon/Nola
Chapman Audio T-7
Usher CP-8871
I see we're not getting into the time/phase discussion. Slope backed or staggered baffles?
Advantage of Fulton Modulars is you can slide them front or back to suit. Or twist... toe in the tweeters if you want. :yes:
Single-drivers: OHM? Concentrics: KEF?
Fulton Modulars
Alon/Nola
Chapman Audio T-7
Usher CP-8871
I see we're not getting into the time/phase discussion. Slope backed or staggered baffles?
Advantage of Fulton Modulars is you can slide them front or back to suit. Or twist... toe in the tweeters if you want. :yes:
Single-drivers: OHM? Concentrics: KEF?
Last edited:
A letter never published Fried
]Auricle Publishing ©2008
Fried Letter to Stereophile
by Richard Hardesty
I believe that speakers should preserve the integrity
of the signal waveform and the Audio Perfectionist
Journal has presented a great deal of information
about the importance of time domain performance in
loudspeakers. I’m not the only one who appreciates
time- and phase-accurate speakers but I have been
virtually the only advocate to speak out in print in
recent years. There’s a reason for that.
Few of today’s high-end loudspeakers are time- and
phase-accurate designs. The audio magazines need
to appeal to a broad spectrum of advertisers including
many who make speaker systems which are time
incoherent. The magazines, and the reviewers who
write for them, have ignored or downplayed the issue
of time- and phase-accuracy in order to maximize
advertising revenue. As you can see from this letter I
am not alone in recognizing this situation.
Legendary speaker designer Irving M. “Bud” Fried
wrote a letter about this subject to John Atkinson,
editor of Stereophile magazine, in response to a comment
that John made in one of his product reviews.
Stereophile chose not to publish Fried’s letter but I
received a copy. Following is an edited version for
your information.
July 20, 2002
Dear Mr. Atkinson,
This communication is offered for the sake of objectivity
and “truth” (a commodity not in high regard
these last few weeks, at least in the world of commerce).
In your August 2002 issue, page 63, you wrote “the
use of a high order crossover means that the MBL
111B is not time coherent (not that that really matters).”
I think it really does matter and I’ll provide
some evidence.
Within the last two years, in what I believe was the
December 2000 issue of the English magazine “HI
FI NEWS,” an article appeared, written, I believe, by
Keith Howard, which detailed the following:
Using a B&W Nautilus Loudspeaker, which has sharp
filters and thus is not time coherent, a tape was specially
prepared of several kinds of music. This tape
was digitally time corrected, so that the resulting
output from the B&W speakers, was a time coherent
signal.
An expert listening panel compared the output of the
speaker from the digitally time corrected tape to the
output of the speaker from the uncorrected tapes. The
www.audioperfectionist.com
1
Watch Dog #12
Irving M. “Bud” Fried
Writes to John Atkinson
Watch Dog #12
Irving M. “Bud” Fried
Writes to John Atkinson
Watch Dog #12
2
entire listening panel voted unanimously for the superior realism
and accuracy of the time corrected output! The article concluded
that this should put to rest for all time the misconception
that time accuracy is not important for high quality reproduction,
contrary to the belief that your quotation expresses!
Michael Gerzon, in lab work for B&W some ten years before,
arrived at the same conclusion. You may remember that he is
the creator of “Ambisonics”—mentioned in various writings of
yours truly.
Yet the new super speakers that turn up in the marketplace
are overwhelmingly non-time coherent! Perhaps this really is
due entirely to “commercial considerations,” as I was once told
by my dear friend Raymond Cooke, founder and Managing
Director of the esteemed KEF brand, when I questioned him on
why KEF speakers were not time coherent.
I interpreted Mr. Cooke’s comment to mean that “it’s too expensive
to make KEF speakers time coherent.” And so, with his
help, I proceeded to make my own brands time coherent!
I have demonstrated the same condition of “time coherence”
for many years—and written extensively about it. Perhaps it
is time for your readers to hear that time coherence has its
proponents—even though it is not much in evidence in today’s
“super speakers.” In fact, the more time coherent loudspeaker
condition is always preferred by those who value ”live” sound
quality over “commercial considerations.”
I am always available at the stated address—if readers want
the other side of the coin.
Sincerely,
Irving M. (Bud) Fried
300 E. Lancaster Ave.
Wynnewood, PA 19096
www.audioperfectionist.com
APJ
]Auricle Publishing ©2008
Fried Letter to Stereophile
by Richard Hardesty
I believe that speakers should preserve the integrity
of the signal waveform and the Audio Perfectionist
Journal has presented a great deal of information
about the importance of time domain performance in
loudspeakers. I’m not the only one who appreciates
time- and phase-accurate speakers but I have been
virtually the only advocate to speak out in print in
recent years. There’s a reason for that.
Few of today’s high-end loudspeakers are time- and
phase-accurate designs. The audio magazines need
to appeal to a broad spectrum of advertisers including
many who make speaker systems which are time
incoherent. The magazines, and the reviewers who
write for them, have ignored or downplayed the issue
of time- and phase-accuracy in order to maximize
advertising revenue. As you can see from this letter I
am not alone in recognizing this situation.
Legendary speaker designer Irving M. “Bud” Fried
wrote a letter about this subject to John Atkinson,
editor of Stereophile magazine, in response to a comment
that John made in one of his product reviews.
Stereophile chose not to publish Fried’s letter but I
received a copy. Following is an edited version for
your information.
July 20, 2002
Dear Mr. Atkinson,
This communication is offered for the sake of objectivity
and “truth” (a commodity not in high regard
these last few weeks, at least in the world of commerce).
In your August 2002 issue, page 63, you wrote “the
use of a high order crossover means that the MBL
111B is not time coherent (not that that really matters).”
I think it really does matter and I’ll provide
some evidence.
Within the last two years, in what I believe was the
December 2000 issue of the English magazine “HI
FI NEWS,” an article appeared, written, I believe, by
Keith Howard, which detailed the following:
Using a B&W Nautilus Loudspeaker, which has sharp
filters and thus is not time coherent, a tape was specially
prepared of several kinds of music. This tape
was digitally time corrected, so that the resulting
output from the B&W speakers, was a time coherent
signal.
An expert listening panel compared the output of the
speaker from the digitally time corrected tape to the
output of the speaker from the uncorrected tapes. The
www.audioperfectionist.com
1
Watch Dog #12
Irving M. “Bud” Fried
Writes to John Atkinson
Watch Dog #12
Irving M. “Bud” Fried
Writes to John Atkinson
Watch Dog #12
2
entire listening panel voted unanimously for the superior realism
and accuracy of the time corrected output! The article concluded
that this should put to rest for all time the misconception
that time accuracy is not important for high quality reproduction,
contrary to the belief that your quotation expresses!
Michael Gerzon, in lab work for B&W some ten years before,
arrived at the same conclusion. You may remember that he is
the creator of “Ambisonics”—mentioned in various writings of
yours truly.
Yet the new super speakers that turn up in the marketplace
are overwhelmingly non-time coherent! Perhaps this really is
due entirely to “commercial considerations,” as I was once told
by my dear friend Raymond Cooke, founder and Managing
Director of the esteemed KEF brand, when I questioned him on
why KEF speakers were not time coherent.
I interpreted Mr. Cooke’s comment to mean that “it’s too expensive
to make KEF speakers time coherent.” And so, with his
help, I proceeded to make my own brands time coherent!
I have demonstrated the same condition of “time coherence”
for many years—and written extensively about it. Perhaps it
is time for your readers to hear that time coherence has its
proponents—even though it is not much in evidence in today’s
“super speakers.” In fact, the more time coherent loudspeaker
condition is always preferred by those who value ”live” sound
quality over “commercial considerations.”
I am always available at the stated address—if readers want
the other side of the coin.
Sincerely,
Irving M. (Bud) Fried
300 E. Lancaster Ave.
Wynnewood, PA 19096
www.audioperfectionist.com
APJ
70chevelle
Active Member
That's interesting. The first pair of speakers I purchased in 1982/3 were a pair of MCS (JC Penney) that were very similar, but 8" woofer only, no passive. I know I had the brochure for those speakers memorized when I bought them, but can't remember today what the 'catch phrase' was. Maybe it will come to me. My uncle still uses them with a Technic's reciever and tape deck. I'll have to check them out next time I'm over.
Found it! Linear Phase!!!!!!
Last edited:
philcib
Well-Known Member
I believe that the MCS speakers were clones of the Technics speakers. Here is a link to my thread regarding my Technics SB-4000's, where one respondent says they have MCS that are exactly the same. http://www.audiokarma.org/forums/showthread.php?p=2682688
tubino
A guy with too many tubes
If I use Tannoy (or other) dual concentrics so the voice coils are concentric, and use the same order crossover on top and bottom, isn't that in a real sense time-aligned, such that the signal from both drivers is phase-aligned and time-aligned whether I'm on- or off-axis, or any distance from the speaker?
Cuz it sounds like that.
To get the timing right we need the acoustic LF and HF waves to arrive together.
The position of the magnets and Voice Coils is part of the equation .The crossover
is the other part, and the only part we can change. By adding the proper amount of delay we can get the waves to arrive together
See my web site.
http://web.mac.com/donaldpatten/
The position of the magnets and Voice Coils is part of the equation .The crossover
is the other part, and the only part we can change. By adding the proper amount of delay we can get the waves to arrive together
See my web site.
http://web.mac.com/donaldpatten/
SaSi
Seriously Illogical
A stupid - perhaps - question.
Having aligned the voice coils of the drivers vertically, if the speaker is driven by an active crossover and dual power amps, will the two frequency channels be in time alignment?
I have this question because passive crossovers tend to have different phase differences depending on the frequency. Is that a behavior of a passive xover only or do active ones have the same behavior?
Having aligned the voice coils of the drivers vertically, if the speaker is driven by an active crossover and dual power amps, will the two frequency channels be in time alignment?
I have this question because passive crossovers tend to have different phase differences depending on the frequency. Is that a behavior of a passive xover only or do active ones have the same behavior?
I just purchased a pair of Meadowlark Kestrels. My first time aligned first order speaker technology. I have heard Vandersteens so I thought these would sound like those. No way, I always thought Vandesteens were coherent but a little dull sounding. The Kestrels are anything but, they are dynamic with good bass (room dependent) the high notes are there but not in your face. That part takes a little getting use to, but I think are more correct in thier presentation. When you listen to live music, the high notes aren't in your face. The imaging is fantastic, you can pick out every instument, even when the music is complex. These are the lower line speakers for Meadowlark I would like to here what thier upper end speakers sound like. Sadly they are out of business, that is to bad......:sigh:
Susurus
Resolution:6.62×10^-34
Not lucky enough to've spotted Meadowlarks IRL yet. I need the birdwatcher's patience.
Heard a set of Vandy 2's that were factory-restored through a GA-777ES. Man that was nice. (Needed some juice--through my smaller 55-wpc Sansui, it lacked dynamics and some of that bass.)
Just treat them as you would Carver Amazings, or other limited or open baffle sets. Location, location, location.
Heard a set of Vandy 2's that were factory-restored through a GA-777ES. Man that was nice. (Needed some juice--through my smaller 55-wpc Sansui, it lacked dynamics and some of that bass.)
Just treat them as you would Carver Amazings, or other limited or open baffle sets. Location, location, location.
Radfordman
Super Member
Electrostatics!
SaSi
Seriously Illogical
OK, let me rephrase: If the acoustic centers of the two drivers are aligned, is the delay introduced by active and passive xovers constant or does it shift by frequency?
Radfordman
Super Member
Tannoy Dual Concentrics may be quite well time aligned.
tubino
A guy with too many tubes
Many years ago when I bought my first really great speakers, I listened to the Kestrels and other Meadowlarks. I thought they were very impressive. The same dealer (Arthur's Audio) also had Harmonic Precision Echelons (their TOTL), which to me sounded similar but still better at both freq extremes, and extremely coherent. (sophisticated series crossover) That company isn't around any more either, but I think those are a reasonable move up for someone liking Kestrels.
Another benefit is that the Echelons are very tube friendly, with impedance never dipping below 7.5 ohms. Mine are at a friend's -- he likes them for classical, but they can rock too.