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    fully modified PAS3 - or a new SP12 ??

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    tubes4hifi
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    fully modified PAS3 - or a new SP12 ??

    Post by tubes4hifi on Sat Jun 15, 2013 7:43 pm

    I get this question 2 or 3 times a month, so I'm gonna post my answer here for the entire world to see . . .


    I never recommend doing all the necessary mods to a PAS3 unless you absolutely have to have a preamp in that chassis.
    The power transformer in a PAS3 is crap. The circuits were only passable (PAS) 50 years ago.
    For the cost of all the upgrades (I've done severals PAS3's with $1000 worth of mods) you can buy the superior SP10 or SP12 preamp for less money.
    At an absolute minimum, for a PAS3 to have decent performance, I would recommend nearly every mod on my website
    www.tubes4hifi.com/PAS3-CAT.htm
    To come close to the performance of the SP12 I would recommend the regulated power supply, the PAS-AIKIDO line stage, and PH10 phono (if you want phono).
    That is items # 2,3,4,6,18,19, 28, plus new tubes # 24 & 25, so just the parts alone add up to $512. If you need them assembled and installed,
    it's right about $1000 not including the cost of the original PAS3. A decent used PAS3 is about $300.
    You can buy an SP10 kit starting at $650. For an assembled SP12 including phono the price is around $1300.
    On my own rating scale of 1 to 10, a PAS3 is a 1 (comparable to a used $300 preamp). An SP14 is a 10 (comparable to a new tube preamp in the $3000+ range).
    A modified PAS3 with the premium mods would be about a 7, and SP12 would be about an 8.

    just my own opinion, of course . . . 
    (but this is after 25 years and at least 25 different preamps, and having modified at least 25 PAS3s, and having built at least 25 SP12s and SP14s)

    just to add more insult to the injured . . . I'm also NOT a fan of any Audio Research gear.  Their power supplies are so complex they destroy the tube sound.
    So what DO I like that I've owned?   somebody is bound to ask eventually . . . CJ PV8, PV10, PV12.   Marantz 7, Luxman CL34 (both from 30+ years ago).
    If I had to buy a new preamp, it would have to be a minimum of a Cary SLP-03 ($2000) or a BAT VK-3ix ($2500-3500).
    But I'd also be happy with my own SP10. I'd take my own SP14 over any preamp at any price!

    tubes4hifi
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    Re: fully modified PAS3 - or a new SP12 ??

    Post by tubes4hifi on Fri Apr 03, 2015 10:22 pm

    this sticky is almost two years old and I still get these same questions every month, so this time I'll explain why I'd rather sell you an SP9 preamp than have you buy all the good parts to modify your PAS3 preamp.
    You can buy an average PAS3 on ebay for around $350, $300 for one not so good, or $400 for a better one, but let's say $350, and it needs SOME work (any 50 year old preamp needs SOME work !!!!)
    So you want all the good parts. Looking at my PAS3-CAT page, I'd recommend these items:
    The ultimate mods are #2b, 3a, 3d, 4, 6, 8, 17 (or 18), 19, 23, 25, and 28 which total $562 in parts (and $200 in labor if I do it for you),
    and then you've got a pretty nice preamp for $1100 but it's not as good or nice as an SP9+PH10 that would cost $825 as a kit or $1125 assembled,
    plus you can get $350 back selling the PAS3, so the cost is actually $350 less for a better nicer brand new preamp!!!

    Kentley

    Posts : 300
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    Age : 64
    Location : Worcester, MA

    Re: fully modified PAS3 - or a new SP12 ??

    Post by Kentley on Fri Apr 03, 2015 11:04 pm

    Roy, you are thr Mr. Spock of this forum. "Logic..."
    "Vintage" is a benefit to be weighed carefully. I owned an ARC D-115 {circa 1985} for several days before I bought the ST-120. I will never look back. Not only is the VTA product more transparent, lighter, cooler-running, but it is far less prone to malfunction. Audio Research's Chief Engineer's name was --
    Rube Goldberg.
    Listen to Spock, folks. He's been there far longer than most of us. I hear his home star system is Arcturus....

    tubes4hifi
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    Re: fully modified PAS3 - or a new SP12 ??

    Post by tubes4hifi on Fri Apr 03, 2015 11:10 pm

    don't even get me started on Audio Research gear . . .
    I would probably offend everyone except the people who own VTA amps from "tubes4hifi"
    I'm sure if someone tried hard enough they would find evidence of my previous rantings about ARC gear.
    All I will say for now . . . . nice design, nice looks, priced 10X as high, and the power supplies TOTALLY DESTROY THE SOUND.
    OK, now I will shut my face hole.

    Kentley

    Posts : 300
    Join date : 2015-03-06
    Age : 64
    Location : Worcester, MA

    Re: fully modified PAS3 - or a new SP12 ??

    Post by Kentley on Fri Apr 03, 2015 11:14 pm

    Sound of the D-115 was impressive. But somehow WAY too exaggerated. Then the thing pulled a Vesuvius on me.....
    Give me VTA, or give my Mom a retroactive abortion.

    jimmytamp

    Posts : 7
    Join date : 2013-06-24

    Re: fully modified PAS3 - or a new SP12 ??

    Post by jimmytamp on Sat Jul 09, 2016 10:08 pm

    tubes4hifi wrote:I get this question 2 or 3 times a month, so I'm gonna post my answer here for the entire world to see . . .


    I never recommend doing all the necessary mods to a PAS3 unless you absolutely have to have a preamp in that chassis.
    The power transformer in a PAS3 is crap. The circuits were only passable (PAS) 50 years ago.
    For the cost of all the upgrades (I've done severals PAS3's with $1000 worth of mods) you can buy the superior SP10 or SP12 preamp for less money.
    At an absolute minimum, for a PAS3 to have decent performance, I would recommend nearly every mod on my website
    www.tubes4hifi.com/PAS3-CAT.htm
    To come close to the performance of the SP12 I would recommend the regulated power supply, the PAS-AIKIDO line stage, and PH10 phono (if you want phono).
    That is items # 2,3,4,6,18,19, 28, plus new tubes # 24 & 25, so just the parts alone add up to $512. If you need them assembled and installed,
    it's right about $1000 not including the cost of the original PAS3. A decent used PAS3 is about $300.
    You can buy an SP10 kit starting at $650. For an assembled SP12 including phono the price is around $1300.
    On my own rating scale of 1 to 10, a PAS3 is a 1 (comparable to a used $300 preamp). An SP14 is a 10 (comparable to a new tube preamp in the $3000+ range).
    A modified PAS3 with the premium mods would be about a 7, and SP12 would be about an 8.

    just my own opinion, of course . . . 
    (but this is after 25 years and at least 25 different preamps, and having modified at least 25 PAS3s, and having built at least 25 SP12s and SP14s)

    just to add more insult to the injured . . . I'm also NOT a fan of any Audio Research gear.  Their power supplies are so complex they destroy the tube sound.
    So what DO I like that I've owned?   somebody is bound to ask eventually . . . CJ PV8, PV10, PV12.   Marantz 7, Luxman CL34 (both from 30+ years ago).
    If I had to buy a new preamp, it would have to be a minimum of a Cary SLP-03 ($2000) or a BAT VK-3ix ($2500-3500).
    But I'd also be happy with my own SP10.  I'd take my own SP14 over any preamp at any price!

    I got SP12R/PH12 from Roy since 2014, so far so good and I really love them.

    Thanks Roy for the high quality built.

    Cheers,
    Jimmy

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    Re: fully modified PAS3 - or a new SP12 ??

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