Topic: Repair or replace 1976 Phase Linear 400 amp?

[bootray]

My 1976 PL 400 had some output transistors and caps replaced a few years ago
and I have been happy. Recently an unpleasant sound and smell was emitted from the 400 indicating another trip to the shop for caps and transistors. Soon it will be 
totaly restored, but at what price? I already dumped $200 in it, and the unit is only
worth around $400. I am currently using the 400 to power my MG2 pans, along
with a 1966 Marantz 7T Preamp, Rega 2.5 w/Dynavector 10x5. Not super high end
gear but very nice sound.
The pans are power hungry and a pal suggested that I consider a high power
sound reinforcement amp like a used Crest or Crown. He says design
improvements make these   amps as clean and transparent as the used audiophile
amps at Audiogon. Is this true?
I have a limited budget of around $500.
High power transistor amps are not cheap, even used, on Audiogon and 4-600
watt models are scarce. I seem to remember a high watt Audio Research
transistor amp from 30 years ago. I am hard pressed to think of good options.
Many of you have audiophile knowledge here and I trust your opinions.
Suggestions please? Thanks for your time...
Ray

[cshepherd]

I'm sure your friend means well, but Crest and Crown amps aren't what you're looking for.  400-600 watts just aren't necessary in a house.   Magnepans are 5 ohm loads and they need a little juice, but 100-150 watts is plenty.  I think you'd be better off selling your pre amp and buying a higher quality integrated (like a Musical Fidelity or a McIntosh) and avoiding the pro audio market.  I know the MF amps have built in phono stages sufficient for your high output MC cart.

Good luck,
Chris

[boojum]

It seems we always disagree opn something.     OK, I run two hafler 500's mono-bridged to put out ~1,200 watts into 4 ohms steady.  I drive SoundLab Pristines, KEF 104/2's and a pair of AR2ax's with them.  The Pristines suck up a lot, the KEF's can handle it and sometimes (Funkytown) cause the amps to overheat and go into cool-down mode.  This is an extreme case.  In the '39 Worlds Fair Western Electric tested a lot of audio - developed the Fletcher-Munson curve as a part of it - and determined that 80 watts was necessary to faithfully reproduce solo piano.  And that was when speakers were pretty efficient. 

I like a lot of headroom.  I do not always bend the walls with playing it too loud, in fact I do that very rarely.  But I am assured of ample headroom for anything.  So, it is a difference of opinion.  My solution for you: listen to various setups.  Try out the two or three at home you really like and see what works the best.  It is like picking mics for a venue: some work better than others.  And buy a little more quality than you can afford.  You won't regret it.

[cshepherd]

Well, we both own Sound Labs.  That's a start   .  There was a set of mid-80's Maggies in our family for a number of years.  I would rather power them with 100 watts that cost $5 per watt than 500 watts that cost $1 per watt.

Chris

[tiberiusbkirk]

wow, this is the first forum I've been in where there's two
members who have Sound Labs speakers.
Both my brother and BIL has them, driven by Krell KSA 250's.
Is there a team Sound Lab or something?

[guysonic]

There were many owners of Phase Linear power amps (sometimes called 'Flame' Linear) that swear by them for exceptional good sounding powerful operation (BUT also known to frequently 'swear at them' for burning up). 

Good advice to look for more stable modern power amp not requiring you to keep you fingers crossed and a ready fire extinguisher.

[boojum]

Well, we both own Sound Labs.  That's a start   .  There was a set of mid-80's Maggies in our family for a number of years.  I would rather power them with 100 watts that cost $5 per watt than 500 watts that cost $1 per watt.

Chris

You wouldn't happen to be selling the "100 watts that cost $5 a watt would you?"      Other than that I do not see your point. Unless it is to get less bang for your buck.  I own SoundLabs, KEF 104/5's, AR2ax's and a pair of small Paradigms.  They all have their virtues.  The SL's are the finest sounding speakers I have ever heard.  I am sending them back to get re-voiced (new upgraded diaphragms).  I love 'em.

[Frank in JC]

Other than that I do not see your point.

Watts are not created equally.

[boojum]

Quality was not a parameter.  The statement was: "I would rather power them with 100 watts that cost $5 per watt than 500 watts that cost $1 per watt."   The differences are minimal at best and illusory at worst.  When the amps can be distinguished as "better" and "worse" in a double-blind test then I will accept with ease that one is better than the other.  Until then it is no more than very subjective opinion.   

[Frank in JC]

Quality was not a parameter.  The statement was: "I would rather power them with 100 watts that cost $5 per watt than 500 watts that cost $1 per watt."   The differences are minimal at best and illusory at worst.  When the amps can be distinguished as "better" and "worse" in a double-blind test then I will accept with ease that one is better than the other.  Until then it is no more than very subjective opinion.   

Sorry, I didn't realize you're a DBT'er.  I understand now 

[Church-Audio]

My 1976 PL 400 had some output transistors and caps replaced a few years ago
and I have been happy. Recently an unpleasant sound and smell was emitted from the 400 indicating another trip to the shop for caps and transistors. Soon it will be 
totaly restored, but at what price? I already dumped $200 in it, and the unit is only
worth around $400. I am currently using the 400 to power my MG2 pans, along
with a 1966 Marantz 7T Preamp, Rega 2.5 w/Dynavector 10x5. Not super high end
gear but very nice sound.
The pans are power hungry and a pal suggested that I consider a high power
sound reinforcement amp like a used Crest or Crown. He says design
improvements make these   amps as clean and transparent as the used audiophile
amps at Audiogon. Is this true?
I have a limited budget of around $500.
High power transistor amps are not cheap, even used, on Audiogon and 4-600
watt models are scarce. I seem to remember a high watt Audio Research
transistor amp from 30 years ago. I am hard pressed to think of good options.
Many of you have audiophile knowledge here and I trust your opinions.
Suggestions please? Thanks for your time...
Ray

I would get a Bryston 4b and be done with it IMO its one of the best power amps ever made. And the 25 year warranty ain't to bad ether.. Some here say stay away from the pro market.. I strongly disagree! Check out Bryston..

Chris

[boojum]

Quality was not a parameter.  The statement was: "I would rather power them with 100 watts that cost $5 per watt than 500 watts that cost $1 per watt."   The differences are minimal at best and illusory at worst.  When the amps can be distinguished as "better" and "worse" in a double-blind test then I will accept with ease that one is better than the other.  Until then it is no more than very subjective opinion.   

Sorry, I didn't realize you're a DBT'er.  I understand now 

Yes, it is hard to argue with facts.  Subjective impressions are valued nowhere as highly as in the world of high-end audio.  And testing, which is accepted in every scientific and engineering arena, is decried in high-end audio.  There has to be a reason that facts are rejected.   

[guysonic]

Quality was not a parameter.  The statement was: "I would rather power them with 100 watts that cost $5 per watt than 500 watts that cost $1 per watt."   The differences are minimal at best and illusory at worst.  When the amps can be distinguished as "better" and "worse" in a double-blind test then I will accept with ease that one is better than the other.  Until then it is no more than very subjective opinion.   

Audible differences between amps with nearly identical specifications do occur for a few reasons.

One is because different types of speakers present very unique complex (NOT simple passive resistive) loads to an amps output making driving clean sounding audio and/or surviving without output stage burnout a design challenge.

[boojum]

In a double-blind test all would be the same but the item being tested.  In this case the amps.  Stereo Review ran a "DBT" at a show years ago.  All attendees were invited to participate.  Hands down a cheap receiver beat out an expensive Levinson dual-mono stereo package.  Just another reason that high-end audio hates DBT.  As usual, YMMV     

[guysonic]

In a double-blind test all would be the same but the item being tested.  In this case the amps.  Stereo Review ran a "DBT" at a show years ago.  All attendees were invited to participate.  Hands down a cheap receiver beat out an expensive Levinson dual-mono stereo package.  Just another reason that high-end audio hates DBT.  As usual, YMMV     

Hard to believe, AND likely not really true rumor-tech stuff anyway.  Don't you just HATE getting the 'conclusive results' without the glory details making all the difference for chance of knowing truths of the matter. 

In this case. and if being shocked to attention by out-of-technical-context claims, think better to have ability to drill a little deeper knowing the magazine issue and full testing setup details.  Otherwise to me, just another unsubstantiated rumor holding only limited truth for normal user expectations and working conditions.