MagicMarksy
Member
Hi all,
I am following the many suggestions I have gotten over the past few days and I am going to commit some of my time and start some new threads. I am hoping that AudioKarma thinks these threads are valuable enough to make "STICKY" so they will be easy to find, as I expect they will be very popular.
So here goes. This is the first one. I have entitled it INFINITY QRS [Quantum Reference Standard] - Inspired US to Build these Speakers.
Many of you older memebers might remember back in the late 1970's (1978) that for a very limited period of time, Infinity actually made a product called the Quantum Reference Standard. This was only available for a very limited amount of time but it INSPIRED a whole array of loudspeakers that followed.
As the story goes.....the heart of the original QRS was the Strathern Midrange Driver. It is a pseudo-ribbon actually invented in the 1950's, if I recall correctly, and for many years it was manufactured in Northern Ireland.
The impedance of the midrange was only 0.55 Ohms so the manufacturer also devised a impedance matching transformer to use with the transducer, making the actual drive impedance of the combined device 8 Ohms. However, Arnie Nudell realized that if you took 3 raw drivers and put them in series you could get a 1.65 Ohm load and that a good high current amplifier could actually drive this load directly without the need for an impedance matching transformer. Eventually he mated 3 of these 2 foot Strathern midrange drivers with 20 Full Line Source EMIT's, that he had manufactured for him by Peerless Loudspeakers of Leominster, Massachusetts (13 facing front and 7 facing the rear), and mated them with a 15 inch woofer thus creating the INFINITY QUANTUM REFERENCE STANDARD soon to be known as the Infinity QRS'.
The next part of the story is that Harry Pearson, of Absolute Sound Fame, reviewed the speaker (Issue 13, 1978) and loved the midrange and high frequency components but thought the woofer was too sluggish to be a good mate for the system. It just so happened that at about the same time he was also reviewing the Audio Research / Magnaplanar Tympani 1D loudspeakers. In a moment of true genius he decided to try to mate the midrange high frequency portion of the Infinity QRS loudspeakers with the Bass panels from the Audio Research / Magnaplanar Tympani 1D loudspeakers and the rest is history.
Resources were limited at the time but he did figure out that the system sounded the best when BI-AMPED and as a crossover he used for the bi-amplification was the Dalquist DQLP1. If I remember correctly the crossover frequency chosen was about 150 Hz.
The combination was an instant success. In many people's opinion this was the first loudspeaker combination ever produced, that even began to approach the sound of LIVE MUSIC. A new name was then COINED for the combination speaker system he just created, and it was called the QRS-1D Hybrid System.
Once this happened, things began to move very quickly. Both Infinity and Audio Research / Magnaplanar took their current products off the market and both set about improving the short comings of each.
For Infinity this lead to the creation of the INFINITY REFERENCE STANDARDS ( IRS ) and for Audio Research / Magnaplanar this lead to the development of the TYMPANI IV's.
For us is the real world this was a great opportunity to BUILD OUR OWN version of the QRS-1D Hybrid System.
I was in Medical School at the time. I knew of Peerless and their development of the EMIT Tweeter for Infinity and KLH and I also knew about STRATHERN in Northern Ireland.
Using the Crewe, VA underground audiophile newspaper the "AUDIOMART" I ran some ads to see if I could interest enough people in helping me import some STRATHERN midranges into the USA from Northern Ireland ,and also went about getting the excess EMIT inventory from Peerless (when Infinity stuck them with it when they went to Japan to have the new EMIM and EMIT speakers manufactured).
I got about 12 people interested and I was eventually able to import, 1st about 24 then 48 and eventually some 96 or so Strathern Miodranges into the USA and I also procurred about 400 EMIT Tweeters from Peerless and ZALYTRON (the people Peerless unloaded them to, when they got stuck with them, when Infinity cancelled their orders and went to Japan to manufacture them). So from about 1982 and 1984 I sent people who were interested the parts to make their own verion of the QRS loudspeakers.
The heart of the speakers always was and always will be the Strathern Midrange Drivers. You could mate them with virtually any woofer to get the bass you needed and if you really desired you could supplement them with the EMIT tweeters for better high end dispersion.
Eventually I graduated from medical school and let Brian Chaney of VMPS Audio fame take over the importing of the Strathern Ribbons into the United States. In a deal to give him the import rights in about 1984, all I really wanted was a few more Strathern's at his cost. He gladly complied and I in turn, turned over the import rights for the Strathern Drivers to him.
I built many speakers using the Strathern Midranges and I will over time post many of them here in this thread. I also know of others from all over the world that did the same and I expect many will post their versions here as well. They kinda all resemble each other.
Of note Mike Desurkio (sp?) of "AUDIO CONCEPTS" also got into the game for a while and made some nice stand alone cabinets available to MAKE YOUR OWN version of the QRS as well. I even have still have a set to this very day.
From INFINITY:
Quantum Reference Standard
Introduced: 1977
Dimensions: 203 x 122 x 61 cm
Bass: 1 x 38 cm
Mids: 3 x EMIRM (Strathearn MRHF)
Highs: 20 x EMIT (7 on the back)
Suggested for amplifiers with: Bass: 150 Watts per channel
Mids/Highs: 100 Watts per channel
Frequency range: 18 Hz - 32 kHz
Crossover frequencies: 100 Hz, 4000 Hz
Suggested price (pair): 6500 $
Please feel free to edit this post and correct the grammer and the spelling. But I at least got it started like I said I would.
So everyone please chime in and enjoy.
Michael Marks
I am following the many suggestions I have gotten over the past few days and I am going to commit some of my time and start some new threads. I am hoping that AudioKarma thinks these threads are valuable enough to make "STICKY" so they will be easy to find, as I expect they will be very popular.
So here goes. This is the first one. I have entitled it INFINITY QRS [Quantum Reference Standard] - Inspired US to Build these Speakers.
Many of you older memebers might remember back in the late 1970's (1978) that for a very limited period of time, Infinity actually made a product called the Quantum Reference Standard. This was only available for a very limited amount of time but it INSPIRED a whole array of loudspeakers that followed.
As the story goes.....the heart of the original QRS was the Strathern Midrange Driver. It is a pseudo-ribbon actually invented in the 1950's, if I recall correctly, and for many years it was manufactured in Northern Ireland.
The impedance of the midrange was only 0.55 Ohms so the manufacturer also devised a impedance matching transformer to use with the transducer, making the actual drive impedance of the combined device 8 Ohms. However, Arnie Nudell realized that if you took 3 raw drivers and put them in series you could get a 1.65 Ohm load and that a good high current amplifier could actually drive this load directly without the need for an impedance matching transformer. Eventually he mated 3 of these 2 foot Strathern midrange drivers with 20 Full Line Source EMIT's, that he had manufactured for him by Peerless Loudspeakers of Leominster, Massachusetts (13 facing front and 7 facing the rear), and mated them with a 15 inch woofer thus creating the INFINITY QUANTUM REFERENCE STANDARD soon to be known as the Infinity QRS'.
The next part of the story is that Harry Pearson, of Absolute Sound Fame, reviewed the speaker (Issue 13, 1978) and loved the midrange and high frequency components but thought the woofer was too sluggish to be a good mate for the system. It just so happened that at about the same time he was also reviewing the Audio Research / Magnaplanar Tympani 1D loudspeakers. In a moment of true genius he decided to try to mate the midrange high frequency portion of the Infinity QRS loudspeakers with the Bass panels from the Audio Research / Magnaplanar Tympani 1D loudspeakers and the rest is history.
Resources were limited at the time but he did figure out that the system sounded the best when BI-AMPED and as a crossover he used for the bi-amplification was the Dalquist DQLP1. If I remember correctly the crossover frequency chosen was about 150 Hz.
The combination was an instant success. In many people's opinion this was the first loudspeaker combination ever produced, that even began to approach the sound of LIVE MUSIC. A new name was then COINED for the combination speaker system he just created, and it was called the QRS-1D Hybrid System.
Once this happened, things began to move very quickly. Both Infinity and Audio Research / Magnaplanar took their current products off the market and both set about improving the short comings of each.
For Infinity this lead to the creation of the INFINITY REFERENCE STANDARDS ( IRS ) and for Audio Research / Magnaplanar this lead to the development of the TYMPANI IV's.
For us is the real world this was a great opportunity to BUILD OUR OWN version of the QRS-1D Hybrid System.
I was in Medical School at the time. I knew of Peerless and their development of the EMIT Tweeter for Infinity and KLH and I also knew about STRATHERN in Northern Ireland.
Using the Crewe, VA underground audiophile newspaper the "AUDIOMART" I ran some ads to see if I could interest enough people in helping me import some STRATHERN midranges into the USA from Northern Ireland ,and also went about getting the excess EMIT inventory from Peerless (when Infinity stuck them with it when they went to Japan to have the new EMIM and EMIT speakers manufactured).
I got about 12 people interested and I was eventually able to import, 1st about 24 then 48 and eventually some 96 or so Strathern Miodranges into the USA and I also procurred about 400 EMIT Tweeters from Peerless and ZALYTRON (the people Peerless unloaded them to, when they got stuck with them, when Infinity cancelled their orders and went to Japan to manufacture them). So from about 1982 and 1984 I sent people who were interested the parts to make their own verion of the QRS loudspeakers.
The heart of the speakers always was and always will be the Strathern Midrange Drivers. You could mate them with virtually any woofer to get the bass you needed and if you really desired you could supplement them with the EMIT tweeters for better high end dispersion.
Eventually I graduated from medical school and let Brian Chaney of VMPS Audio fame take over the importing of the Strathern Ribbons into the United States. In a deal to give him the import rights in about 1984, all I really wanted was a few more Strathern's at his cost. He gladly complied and I in turn, turned over the import rights for the Strathern Drivers to him.
I built many speakers using the Strathern Midranges and I will over time post many of them here in this thread. I also know of others from all over the world that did the same and I expect many will post their versions here as well. They kinda all resemble each other.
Of note Mike Desurkio (sp?) of "AUDIO CONCEPTS" also got into the game for a while and made some nice stand alone cabinets available to MAKE YOUR OWN version of the QRS as well. I even have still have a set to this very day.
From INFINITY:
Quantum Reference Standard
Introduced: 1977
Dimensions: 203 x 122 x 61 cm
Bass: 1 x 38 cm
Mids: 3 x EMIRM (Strathearn MRHF)
Highs: 20 x EMIT (7 on the back)
Suggested for amplifiers with: Bass: 150 Watts per channel
Mids/Highs: 100 Watts per channel
Frequency range: 18 Hz - 32 kHz
Crossover frequencies: 100 Hz, 4000 Hz
Suggested price (pair): 6500 $
Please feel free to edit this post and correct the grammer and the spelling. But I at least got it started like I said I would.
So everyone please chime in and enjoy.
Michael Marks