Substandard Components Claims

NavLinear

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#1
Ed,

I was reading on another audio site thread where one of the members claims that Phase Linear did not use the "best parts available" and I'm pretty sure he was inferring substandard components were used and that the output drivers were transistors rejected by the auto industry. I've never heard claims of that sort before and I responded that I'd ask a couple of techs that have worked on these for many years and continue to work on them today what their thoughts are.

Thanks - Dennis
 

eminence1963

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#2
Ed,

I was reading on another audio site thread where one of the members claims that Phase Linear did not use the "best parts available" and I'm pretty sure he was inferring substandard components were used and that the output drivers were transistors rejected by the auto industry. I've never heard claims of that sort before and I responded that I'd ask a couple of techs that have worked on these for many years and continue to work on them today what their thoughts are.

Thanks - Dennis
I read that before back in the day too.:confused1:
 

ksrigg

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#3
I would venture a guess, that there were not any "substandard" parts used.

Back in the Seventies, I don't think there were that many parts available...and I doubt that Bob Carver would have staked his reputation on substandard parts.

By todays standards, we know they were less quality than what can be produced today, and White Oak has even brought todays technology to bear on the original design and made it pretty much bulletproof. (and Joe has optimized the design)

Ed and Joe could best speak to this subject as they both understand the circuit and would be familiar with what was available back in the day !
 
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gadget73

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#5
Judging the quality of parts 35 years later is easy to do. Compared to what you can get today, it probably is crap. At the time though, looking at what was available when these were new its probably a very different story. Even if you look at component changes through the run of the amplifiers, you can see that parts were upgraded as technology improved.
 

laatsch55

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#7
The DTS-411's (RCA) were what the XPOL-909's started out as. Not an audio part. Used in automotive CD ignition systems, the only TO-3 at the time capable of the voltage swing. I wouldn't say he used the best parts possible , but used what would work. The bean counters overtook the company and the quality did suffer for quite awhile...
 

Pure_Brew

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#8
Fine engineering takes the parts and refines a design to get optimal results.

Parts do not usually quantify a good product. For a marketing or "rat in the head" perspective, parts are very important.

I think this way when people say ALL paper cones are trash, for example.
 

MarkWComer

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#9
The worst I've heard of PL is the "Blaze Linear" and "Flame Linear" fables. I have to admit that they scared me a bit while I was researching them, but I've been salivating over those amps since 1983. I don't think my choice was a stupid one.
 

Elite-ist

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#10
Back in the late 70's, my friend and workmate, Mike, had a great stereo system. He is about 5 years older than me. At his house parties, he fondly called his PL amp a "Fuzz Linear."

Nando.
 

gadget73

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#14
Are they CC? Pretty sure mine are wire-wound. The two seams on the case tend to indicate that anyway. Also, the fact that they don't seem to have drifted any in the last 30 years tends to make me think they are not carbon comp.
 

CASSETTE DECK

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#15
I always felt critical of the carbon emitter resistors that put the flame in Phase Linear. These could have been better parts.
Are they CC? Pretty sure mine are wire-wound. The two seams on the case tend to indicate that anyway. Also, the fact that they don't seem to have drifted any in the last 30 years tends to make me think they are not carbon comp.
The old emitter resistors are wire wound, bakelite molded / encapsulated.

http://forums.phxaudiotape.com/show...h-PL-14B-board?p=119233&viewfull=1#post119233
 
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Gepetto

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#16

CASSETTE DECK

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#17
Correct the emitter resistors in Phase Linear amps are WW, the IRC 2W rating in a 1W case size (and not flameproof). The Zoebel resistors generally speaking (you cannot swear for anything in a PL amp) are carbon comp resistors.
The two 10 ohm carbon composition resistors connected in parallel in the zobel networks shown here don't have two visible seams, suggesting that the resistor body was formed before the carbon composition resistor element or that a different molding technique was used.

http://forums.phxaudiotape.com/show...ut-DC-protection?p=92024&viewfull=1#post92024
 
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Gepetto

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#18
The two 10 ohm Carbon composition resistors connected in parallel in the zobel network shown here don't have two visible seams, suggesting that the resistor body was formed before the carbon composition resistor element or that a different molding technique was used.

http://forums.phxaudiotape.com/show...ut-DC-protection?p=92024&viewfull=1#post92024
I do not know how they mold the carbon comp resistor shells. I have thousands of them and they are all smooth molded shells, all the same, suspect that the ejector pin is on one end of them rather than the split body shown on most WW types.
 
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