Much appreciated. There is one error in the information, needing correction for the sake of accuracy. Placing a "woofer" in a cabinet RAISES its free-air resonant point. The excellent bass performance of the AR-4 is consistent with its Total Design Concept called "acoustic suspension", which tuned its dedicated woofer's bass for this particular (closed box) applicarion The same concept was used in the KLH model discussed here.
Well this had little to do with the AR-4x and KLH 17, other than them being representatives of acoustic suspension design, and he owned a pair of 17s long ago. He talks about them being "bookshelf" models, but at the time of their production all of the speakers from AR and KLH were bookshelf sized, except for the KLH-Nine. This brief talk might have better been labeled "Hi-Fi History: The development of acoustic suspension speakers and affordable stereo systems". There was nothing specific about either tilted model other that driver sizes. Hopefully other efforts in this series will be more specific and more correct in details (see comments below).
FWIW, there was no "team" involved in creating the acoustic suspension loudspeaker. Edgar Vilchur invented it and he wanted to sell the concept to a large speaker company but none of the big speaker makers were interested. Henry Kloss encouraged Vilchur to go into business to make/sell them so the two started a company to market them...Acoustic Research.
Well stated. I understand the whole picture now, overall I mean. I have the AR-4x cabs fully functioning paired with an Optonica SM-4545 and it's a GREAT match. So sweet and detailed.
By The Way: the Primary purpose of the ubiquitous cabinet used for loudspeakers is to prevent the rear sound from canceling the frontal sound. But this has been managed in specific manner in speakers which do Not block the rear wave (see Magnepan, Quad, and several others).
I bought a pair of AR 4's Ax I think in 1970. I still have them. The woofer surround was some kind of gauze with a black coating that left the surround somewhat porous. Certainly not "sealed" There was an AR ad that showed one blowing out a candle with it's excursion. I've replaced the woofer a few times over the years. I have a Goldwood at the moment and was unhappy with the bass. I looked up the suggested cabinet size and as the AR is about one cubic foot the recommendation from Parts Express was half that.for that woofer. For a sealed cabinet. I took the woofer out and grabbed three 54 cubic in each Classico empty spaghetti sauce jars and shoved all three in. Wrapped each in a dish towel. Put the woofer back and got the bass back. There is something to those small parameters. I changed the dead tweeter for a Vifa 4" midrange being older I can't hear 12khz or 10khz so no point in getting a fancy tweeter. I used the orig AR coil I think it cuts the woofer off at 1khz. Could go lower with the midrange replacing the tweeter. . I used a high quality cap for the mid. Some thoughts on "sealed" and tweeters. . The original woofer surround was loose and porous. Not air tight on the one's I had. I run the speakers about an inch from a large wall. I read somewhere that the wall reinforces the bass to some degree. Guy across the hall from me in the dorm had the smallest metal cased speakers Prob the Radio shack kind and he used to bass the place out on Sunday morning playing Anna Godda Divida at six am. They were impressive. They may have even had the 5" woofers.
you are right sir .because i have some KLH L 83OR 850 BOOKSHELF SPEAKERS and boy the bass hits hard and nice so it gives my SANSUI SP 3500 VINTAGE SPEAKERS A NICE COMPLIMENT.
Thanks for the history of the term. Good video. It sounds like the term "acoustical suspension" was developed by the marketing team of Acoustic Research to differentiate themselves from all of the other companies making sealed speaker designs as well. Sealed speaker=Acoustical Suspension. Lol
Two comments. First the advent(pun intended) of acoustic suspension with deeper bass in smaller boxes roughly coincided with the introduction of stereo records and significantly helped push stereo since it's obviously way easier to put 2 small speakers in a room than 2 large ones. Secondly there were 2 seminal speakers of the early 70s, the Advent as mentioned and the Dynaco A25 which was cheaper and significant competition for the Advent. Plus the A25 is the best selling audio speaker of all time.
KLH 17's were 10 in + 2 1/2 or 3 inch tweeter cone, 1500 hz Xov. - and at 22 in high where pretty big. the cabinets were amazing, for $ 80. each...... in I think 1969 there was a kinda breakthrough - AR 6 replaced the 4 , the EPI 100 with a backwards dome tweeter , and the Dynaco 25, 10 inch bass, 1.5 in dome - the bass had a sort of port. Also of course the Advent which if Ya could deal with the size, was just a breakthrough. the EPI might have been a year later, 1970. I had the dynacos, ( '72 ) Mom the AR 6 both with Pioneer receivers.
This is not right. The air compliance RAISES the resonant frequency of the floppy woofer suspension. That's the whole point. The air takes over from the suspension, and is more linear.
I have a pair of 17s I got at a thrift store for a dollar. The tweeter is blown on one of the speakers or the crossover is toast. It's been years since I hooked them up. I'm considering refurbishing them for use with my HH Scott Stereomaster 299. I also have a pair of AR4x that probably need more work. From what I'm seeing on the web, the 17s are worth refurbishing. I'm using one of the speakers as a side table right now. I'm sure they would be of better use as actual speakers.
Why do you think almost no speaker company uses the acoustic suspension design anymore? Most use ports either on the front on rear of the speakers. The new KLH-5 speakers are acoustic suspension, I think, but seems to be the only one and recent.
I began my journey with the AR4x. They were great
Much appreciated. There is one error in the information, needing correction for the sake of accuracy.
Placing a "woofer" in a cabinet RAISES its free-air resonant point.
The excellent bass performance of the AR-4 is consistent with its Total Design Concept called "acoustic suspension", which tuned its dedicated woofer's bass for this particular (closed box) applicarion
The same concept was used in the KLH model discussed here.
Tom, I look forward to future videos on the history of high-end audio.
Well this had little to do with the AR-4x and KLH 17, other than them being representatives of acoustic suspension design, and he owned a pair of 17s long ago. He talks about them being "bookshelf" models, but at the time of their production all of the speakers from AR and KLH were bookshelf sized, except for the KLH-Nine. This brief talk might have better been labeled "Hi-Fi History: The development of acoustic suspension speakers and affordable stereo systems". There was nothing specific about either tilted model other that driver sizes. Hopefully other efforts in this series will be more specific and more correct in details (see comments below).
These are in need of pretty big bookshelves, especially the KLH's.
FWIW, there was no "team" involved in creating the acoustic suspension loudspeaker. Edgar Vilchur invented it and he wanted to sell the concept to a large speaker company but none of the big speaker makers were interested. Henry Kloss encouraged Vilchur to go into business to make/sell them so the two started a company to market them...Acoustic Research.
Well stated. I understand the whole picture now, overall I mean. I have the AR-4x cabs fully functioning paired with an Optonica SM-4545 and it's a GREAT match. So sweet and detailed.
Thank you, for sharing your knowledge
By The Way: the Primary purpose of the ubiquitous cabinet used for loudspeakers is to prevent the rear sound from canceling the frontal sound. But this has been managed in specific manner in speakers which do Not block the rear wave (see Magnepan, Quad, and several others).
I bought a pair of AR 4's Ax I think in 1970. I still have them. The woofer surround was some kind of gauze with a black coating that left the surround somewhat porous. Certainly not "sealed" There was an AR ad that showed one blowing out a candle with it's excursion. I've replaced the woofer a few times over the years. I have a Goldwood at the moment and was unhappy with the bass. I looked up the suggested cabinet size and as the AR is about one cubic foot the recommendation from Parts Express was half that.for that woofer. For a sealed cabinet. I took the woofer out and grabbed three 54 cubic in each Classico empty spaghetti sauce jars and shoved all three in. Wrapped each in a dish towel. Put the woofer back and got the bass back. There is something to those small parameters. I changed the dead tweeter for a Vifa 4" midrange being older I can't hear 12khz or 10khz so no point in getting a fancy tweeter. I used the orig AR coil I think it cuts the woofer off at 1khz. Could go lower with the midrange replacing the tweeter. . I used a high quality cap for the mid. Some thoughts on "sealed" and tweeters. . The original woofer surround was loose and porous. Not air tight on the one's I had. I run the speakers about an inch from a large wall. I read somewhere that the wall reinforces the bass to some degree. Guy across the hall from me in the dorm had the smallest metal cased speakers Prob the Radio shack kind and he used to bass the place out on Sunday morning playing Anna Godda Divida at six am. They were impressive. They may have even had the 5" woofers.
Purchased my AR-4x speakers in 1968 for $114.00 with a Dynaco SCA 35 and AR- XB turntable. Best entry level system back in the day.
you are right sir .because i have some KLH L 83OR 850 BOOKSHELF SPEAKERS and boy the bass hits hard and nice so it gives my SANSUI SP 3500 VINTAGE SPEAKERS A NICE COMPLIMENT.
Thanks for the history of the term. Good video.
It sounds like the term "acoustical suspension" was developed by the marketing team of Acoustic Research to differentiate themselves from all of the other companies making sealed speaker designs as well.
Sealed speaker=Acoustical Suspension. Lol
Two comments. First the advent(pun intended) of acoustic suspension with deeper bass in smaller boxes roughly coincided with the introduction of stereo records and significantly helped push stereo since it's obviously way easier to put 2 small speakers in a room than 2 large ones.
Secondly there were 2 seminal speakers of the early 70s, the Advent as mentioned and the Dynaco A25 which was cheaper and significant competition for the Advent. Plus the A25 is the best selling audio speaker of all time.
My home theater system is 2 EPI 201's and 4 EPI 100's - no subwoofer is needed:)
KLH 17's were 10 in + 2 1/2 or 3 inch tweeter cone, 1500 hz Xov. - and at 22 in high where pretty big. the cabinets were amazing, for $ 80. each...... in I think 1969 there was a kinda breakthrough - AR 6 replaced the 4 , the EPI 100 with a backwards dome tweeter , and the Dynaco 25, 10 inch bass, 1.5 in dome - the bass had a sort of port. Also of course the Advent which if Ya could deal with the size, was just a breakthrough. the EPI might have been a year later, 1970. I had the dynacos, ( '72 ) Mom the AR 6 both with Pioneer receivers.
This is not right.
The air compliance RAISES the resonant frequency of the floppy woofer suspension.
That's the whole point. The air takes over from the suspension, and is more linear.
I have a pair of 17s I got at a thrift store for a dollar. The tweeter is blown on one of the speakers or the crossover is toast. It's been years since I hooked them up. I'm considering refurbishing them for use with my HH Scott Stereomaster 299. I also have a pair of AR4x that probably need more work. From what I'm seeing on the web, the 17s are worth refurbishing. I'm using one of the speakers as a side table right now. I'm sure they would be of better use as actual speakers.
I absolutely love my HH SCOTTS no one ever talks about them and I think they’re a better speaker than most
Why do you think almost no speaker company uses the acoustic suspension design anymore? Most use ports either on the front on rear of the speakers.
The new KLH-5 speakers are acoustic suspension, I think, but seems to be the only one and recent.
I love this ❤
My KLH 17's blow my ARx4's away. Not in power or loudness, I rarely play very loud. It's just the KLH's sound better.