Rare Phase Linear stuff

"Is your amplifier sleeping on the job?" Love that one!!!
 
SEATTLE AREA MCINTOSH CLINICS 1968-1971 (BOB CARVER'S RESPONSE)

I just got a response from Bob Carver about the McIntosh amplifier clinics. I forwarded him everything I posted on Phoenix about the McIntosh clinics.

Here is what he had to say:

Oh Wow! This is great stuff! Man, what a trip. I can't remember exactly where that graph was made; I can see the inside of the store, Dave O'brian and his test bench, and him signing the graph, but I'm not sure of the store and its outside. It was either Seattle Radio Supply or Seattle Stereo Center. I think. It'll come to me if I concentrate this next week.
I never worked for Seattle Stereo Center, but I helped out from time to time. I was a roving "tough-dog-man" for many TV shops at the time, even while working for Harry at Sea-rad and at Almvig's in the U district.

I have lots of stories; we need to start a tape recorder, tell stories and adventures, then get them transcribed.

Wow again!

More adventures later.
Bob Carver


Ed
 
Photos of Seattle Stereo Dealers Where McIntosh Amplifier Clinics Were Held

Here are a couple jpgs of some of the Seattle stereo dealers where the McIntosh amplifier clinics where held.

Electricraft

Magnolia Camera & Hi-Fi

Seattle Stereo Center

Included in the jpg's is a picture of Seattle Radio Supply where Bob Carver once worked. He also met Rodger Rosenbaum and Ray Weikel there. Rodger and Ray were (2) fellows who worked for Bob's TV repair business and helped with the development of the first Phase Linear 700.

http://www.taihs.org/wp-content/uploads/2014/07/sterodealersinc-front-Seattle.jpg

http://www.taihs.org/wp-content/uploads/2014/07/stereodealersinc-back-Seattle.jpg

Ed
 

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Coffee Can Amplifier

oldphaser said:
I spoke to him about it a number of years ago. There are a variety of different stories I have heard from people that were at the McIntosh clinics or knew Bob at the time. Some people say it exists some people say it doesn't. Some people say it refers to an open chassis. Others say it was a coffee can full of blown output transistors that were accumulated while Bob was designing the original 700. Some say it was kicking around for a while as a door stop. I have seen photos of a coffee can amp in a brand new Folgers coffee can. Needless to say, I will check into the "coffee can" story more for you.
Click to expand...

I found this posted by Dave Ladely on December 19, 2015: http://www.audiocircle.com/index.php?topic=139506.0

Here is what Dave Ladely had to say:

"I have been involved with audio/video since 1965, with Bob Carver. Bob built an amplifier for me with parts i chose and purchased. The amp weighed about 130 pounds, was on three chassis (stereo channels and separate power supply). This very large tube amp, built in late 1966, was far more powerful than the most powerful consumer amps available (McIntosh 275 and dual Marantz Model 9s). Bob and I took it to the McIntosh Clinic when it came to the Seattle area, at Seattle Stereo. The amp blew all the others away. This inspired Bob to build a solid state version, came up with the name Phase Linear in 1967. Bob began building his first solid state Phase Linear 700 amps in 1969, in a house located on 3rd avenue in the north Shoreline area. He soon moved to a larger house on 25th Avenue in the nearby Richmond Beach area, where he continued building Phase Linear 700 amps. In January, 1970, Bob brought a complete amp to the McIntosh Clinic, where it tested at a bit over 350 watts RMS/channel, with very low distortion across the audio frequency band. The story about the "coffee can" amp is not at all true. Bob showed me the amp shortly afterward, along with the report. Bob has humorously went along with this myth, even on Utube, as it makes a good story, but all anyone has to do is read the McIntosh report to verify that they tested a production Phase Linear 700. Anyway, there is no way a 700 watt RMS amp would fit in any coffee can. Get real. Not long afterward, Bob sent a sample to Hirsch-Houck Laboratories to be tested. Audio Magazine published Julian Hirsch's report, where he found that the near universal assumption that 175 watts was "more than enough power for any home" to accurately reproduce any music on any system was not true. He found that his test of Horowitz on the piano required around 500 watts RMS for low distortion, realistic reproduction. After that report, demand for Phase Linear 700 watts suddenly increased until more Phase Linear amps were sold than McIntosh and Marantz combined. Phase Linear was sold to Pioneer in the early 1980s, but, without Bob as designer, the company foundered. At present, I am helping Bob with his new Amazing Line Source speakers, which are just getting into production."


NOTE: The history may be off a little.

The McIntosh clinic was January 15, 1971 at Seattle Stereo Center

Pioneer acquired Phase Linear in August 1978

The address was 19555 23rd N.W.





Ed
 
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That's too much man....I like Detroit Rock City with the Foo Fighters...
 
Love it Ben! Especially the part where the guy is turning the knob asking what the clipping point is and then lights out LMAO!!!! Sort of points to the fact that there was indeed a coffee can 700w amp
 
Tranny/chasis-less. Even watching the motions he makes referring to the coffee can. His hand gestures kinda say it all.
 
Northwinds said:
Love it Ben! Especially the part where the guy is turning the knob asking what the clipping point is and then lights out LMAO!!!! Sort of points to the fact that there was indeed a coffee can 700w amp
Click to expand...

I have spoken on this subject before. Some people say the "coffee can" amp exists. Others do no not.

Two of the people who say it does not were Dave Ladely (Bob's former roommate) who was also the actual inspiration for the first 700 watt amp and Dave O'Brien who conducted the McIntosh clinics.

I met Dave O'Brien at A.P. Van Meter's house on several occasions. Dave and A.P. both worked together at McIntosh and were very good friends. Dave would come out every year around Thanksgiving for a week. I was invited over and asked Dave about the "coffee can" amp. His reply was that a "coffee can" amp refers to an open chassis. Dave did not recall seeing a Folger's coffee can as most people can imagine.

I have spoken to others who had heard from a friend of a friend that it did exist.

I first met Bob at a Speakerlab event when Sunfire still existed. I mentioned the "coffee can" amp and someone spoke up that there was an Sunfire ad in a Hi-Fi magazine with the amp in it. The magazine was sitting on the counter. The amp was in a brand new Folger's coffee can. You can find pictures of this beautiful coffee can on the Carver web site: http://thecarversite.com/yetanotherforum/carversitegalleryamps.aspx

Until I see a real working amp firsthand....... well what am I to assume?

Ed
 
That's a rather new/recent can :la:
 
McIntosh Clinic report on amp that Bob Carver built

I would like a copy of that report and graph by the McIntosh Clinic that Bob Carver is apparently referring to.

In 1967, I recall that Bob Carver and I brought in a large tube amplifier on three chassis to the McIntosh Clinic being held at Seattle Stereo, located across from the Sears, Roebuck store on first avenue just south of downtown Seattle. This amplifier was about twice as powerful as the McIntosh 275 and stereo pair of Marantz model 9s, the most powerful consumer amps available at that time. I wanted much more power than was available, and Bob had been building excellent small custom amps for years. I wanted him to build an amp for me. So I bought the parts and Bob Carver built the amplifier. The performance of this amplifier inspired Bob to start Phase Linear company to build powerful solid state amplifiers. in January, 1970, Bob brought one of his early Phase Linear 700 amps to the McIntosh Clinic. I don't recall any McIntosh Clinic being held at Seattle Radio Supply - I worked there selling audio and TVs from 1965 through 1969. I hired Bob to help me with TV and antenna installations.
I would very much appreciate getting a copy of the 1967 McIntosh lab report as it was lost. I am presently helping Bob with his new ALS speakers.

oldphaser said:
I just got a response from Bob Carver about the McIntosh amplifier clinics. I forwarded him everything I posted on Phoenix about the McIntosh clinics.

Here is what he had to say:

Oh Wow! This is great stuff! Man, what a trip. I can't remember exactly where that graph was made; I can see the inside of the store, Dave O'brian and his test bench, and him signing the graph, but I'm not sure of the store and its outside. It was either Seattle Radio Supply or Seattle Stereo Center. I think. It'll come to me if I concentrate this next week.
I never worked for Seattle Stereo Center, but I helped out from time to time. I was a roving "tough-dog-man" for many TV shops at the time, even while working for Harry at Sea-rad and at Almvig's in the U district.

I have lots of stories; we need to start a tape recorder, tell stories and adventures, then get them transcribed.

Wow again!

More adventures later.
Bob Carver


Ed
Click to expand...
 
McIntosh Clinic at Seattle Stereo about 1967, NOT 1971.

No, I was referring to an earlier McIntoch Clinic held at Seattle Stereo about 1967, NOT 1971, which is a later visit to Seattle Stereo. In fact, John Ledbetter, owner of NW Sound, was employed at Seattle Stereo, on 1st Avenue, Seattle, during that time and he remembers me and Bob lugging that huge amp on three chassis into the clinic. At the time, i was employed in sales at Seattle Radio Supply. This was well before Bob began building Phase Linear amps.
oldphaser said:
I found this posted by Dave Ladely on December 19, 2015: http://www.audiocircle.com/index.php?topic=139506.0

Here is what Dave Ladely had to say:

"I have been involved with audio/video since 1965, with Bob Carver. Bob built an amplifier for me with parts i chose and purchased. The amp weighed about 130 pounds, was on three chassis (stereo channels and separate power supply). This very large tube amp, built in late 1966, was far more powerful than the most powerful consumer amps available (McIntosh 275 and dual Marantz Model 9s). Bob and I took it to the McIntosh Clinic when it came to the Seattle area, at Seattle Stereo. The amp blew all the others away. This inspired Bob to build a solid state version, came up with the name Phase Linear in 1967. Bob began building his first solid state Phase Linear 700 amps in 1969, in a house located on 3rd avenue in the north Shoreline area. He soon moved to a larger house on 25th Avenue in the nearby Richmond Beach area, where he continued building Phase Linear 700 amps. In January, 1970, Bob brought a complete amp to the McIntosh Clinic, where it tested at a bit over 350 watts RMS/channel, with very low distortion across the audio frequency band. The story about the "coffee can" amp is not at all true. Bob showed me the amp shortly afterward, along with the report. Bob has humorously went along with this myth, even on Utube, as it makes a good story, but all anyone has to do is read the McIntosh report to verify that they tested a production Phase Linear 700. Anyway, there is no way a 700 watt RMS amp would fit in any coffee can. Get real. Not long afterward, Bob sent a sample to Hirsch-Houck Laboratories to be tested. Audio Magazine published Julian Hirsch's report, where he found that the near universal assumption that 175 watts was "more than enough power for any home" to accurately reproduce any music on any system was not true. He found that his test of Horowitz on the piano required around 500 watts RMS for low distortion, realistic reproduction. After that report, demand for Phase Linear 700 watts suddenly increased until more Phase Linear amps were sold than McIntosh and Marantz combined. Phase Linear was sold to Pioneer in the early 1980s, but, without Bob as designer, the company foundered. At present, I am helping Bob with his new Amazing Line Source speakers, which are just getting into production."


NOTE: The history may be off a little.

The McIntosh clinic was January 15, 1971 at Seattle Stereo Center

Pioneer acquired Phase Linear in August 1978

The address was 19555 23rd N.W.





Ed
Click to expand...
 
Thanks Dave, a few more pieces to fill in the puzzle. I hope Bob joins this board at some point. This IS the reference site for Phase Linear, it would be great to have the Father of PL as a contributing member
 
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