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    SP13 preamp

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    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    SP13 preamp

    Post by wgallupe on Fri Oct 31, 2014 1:50 pm

    I'm interested in the SP13 preamp as a replacement for my existing vintage Threshold SL-10. Tried to learn more about it but do not get any hits when I search this forum. Seems like the SP14 is the new popular preamp. Any reason why the SP13 has not gained any 'traction' here?

    My reasons for preferring the SP13 over the SP14:
    4" high chassis helps with my limited vertical space. (but I have a solution to accommodate the 5" chassis if I have to)
    Price and availability of 6SN7 tubes scares me. Is this unwarranted?

    Will be paired with my ST-120 amp which I am loving...

    Thanks in advance,
    Wayne

    dougmon

    Posts : 65
    Join date : 2013-11-04
    Age : 60

    Re: SP13 preamp

    Post by dougmon on Fri Oct 31, 2014 4:41 pm

    wgallupe wrote:I'm interested in the SP13 preamp as a replacement for my existing vintage Threshold SL-10. Tried to learn more about it but do not get any hits when I search this forum. Seems like the SP14 is the new popular preamp. Any reason why the SP13 has not gained any 'traction' here?

    My reasons for preferring the SP13 over the SP14:
    4" high chassis helps with my limited vertical space. (but I have a solution to accommodate the 5" chassis if I have to)
    Price and availability of 6SN7 tubes scares me. Is this unwarranted?

    Will be paired with my ST-120 amp which I am loving...

    Thanks in advance,
    Wayne

    I assume you're talking about the price of NOS 6SN7 tubes -- but there are the Tung-Sol reissues, which you can get for as little as $20 apiece. But even if you feel you have to go with NOS tubes, the high cost fo 6SN7 tubes can be somewhat justified -- I've had 6SN7 tubes that lasted for years (well, 3 years, and then I sold the amp, but I haven't heard any feedback about them quitting yet, and the new owner has had the amp for 2 years.)

    As for pairing a VTA pre and power amp -- I have a VTA ST-70 and SP-10, and the pair provide the nicest musical experience I've had in years. Maybe ever. I can remember being this satisfied with my stereo in a long time. Granted, it's not the ST-120 and SP-14, but I have no complaints (except for the high cost of my favorite EL-34s Wink )

    deepee99

    Posts : 1333
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP13 preamp

    Post by deepee99 on Sun Nov 02, 2014 11:44 am

    wgallupe wrote:I'm interested in the SP13 preamp as a replacement for my existing vintage Threshold SL-10. Tried to learn more about it but do not get any hits when I search this forum. Seems like the SP14 is the new popular preamp. Any reason why the SP13 has not gained any 'traction' here?

    My reasons for preferring the SP13 over the SP14:
    4" high chassis helps with my limited vertical space. (but I have a solution to accommodate the 5" chassis if I have to)
    Price and availability of 6SN7 tubes scares me. Is this unwarranted?

    Will be paired with my ST-120 amp which I am loving...

    Thanks in advance,
    Wayne

    Wayne, I've been exceedingly pleased with my SP-13 for the past two years. I purchased it built, as my eyesight ain't what it used to be -- something I learned building a pair of M-125s. Started with new Russian (EH) 6CG7s but found perfection with NOS RCA 6CG7 clear-tops, which are a fifth the price of NOS 6SN7s and easier to come by, from reliable sources in the U.S. and Canada.
    I have no experience with the SP-14 but a couple of knowledgeable folks I've talked two who've A/B'd say they couldn't hear a difference. You won't go wrong with the 13. Sweetest sounding preamp I've ever owned, and I've owned a few ...

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Sun Nov 02, 2014 1:45 pm

    Thanks for the reassurances guys. Yes, I was referring to expensive NOS 6SN7 tubes. Think I'm gonna go for the SP13 kit.
    Deepee, I'll have to look for some RCA clear tops. Thanks for the tip.

    deepee99

    Posts : 1333
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP13 preamp

    Post by deepee99 on Sun Nov 02, 2014 2:01 pm

    wgallupe wrote:Thanks for the reassurances guys. Yes, I was referring to expensive NOS 6SN7 tubes. Think I'm gonna go for the SP13 kit.
    Deepee, I'll have to look for some RCA clear tops. Thanks for the tip.

    Wayne, PM me if you want to know some reliable clear-top tube sources (I'm not one of them, but have dealt around the block a bit). Other guys on this board can weigh in as well. Expect to pay about $100 for an internally matched quad. They last forever, won't stress the power supply.
    The SP-13 won't letcha down.

    tubes4hifi
    Admin

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    Re: SP13 preamp

    Post by tubes4hifi on Sun Nov 02, 2014 10:38 pm

    Hi Wayne, wow, are you the same guy as Greg, he is also buying an SP13
    Also, anybody wants a new one ready assembled, Troy has one he's asking $1300 for with a PH12 built into it, it would be $990 as a kit,
    $300 for 10-20 hours of labor (depending on your experience) is a true bargain!!

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Mon Nov 03, 2014 9:04 am

    tubes4hifi wrote:Hi Wayne, wow, are you the same guy as Greg, he is also buying an SP13
    Also, anybody wants a new one ready assembled, Troy has one he's asking $1300 for with a PH12 built into it, it would be $990 as a kit,
    $300 for 10-20 hours of labor (depending on your experience) is a true bargain!!

    Hi Roy, I might be interested in the one Troy has. Maybe he can post (or PM) details and pics? Nice to know that there is enough room to add a phono board. I got the impression from the info on your web pages that there wasn't. I was first looking at the SP12/PH12 combo for the convenience of one chassis. Then I decided that the performance boost offered by the SP13/SP14 was more important.

    BTW, I'm not Greg scratch

    Thanks,
    Wayne

    deepee99

    Posts : 1333
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP13 preamp

    Post by deepee99 on Mon Nov 03, 2014 11:58 am

    Wayne,
    I can personally vouch for Troy's (tmadden) skills and attention to perfection.

    Alan-14

    Posts : 46
    Join date : 2012-03-31
    Age : 56
    Location : Melbourne - Australia

    Re: SP13 preamp

    Post by Alan-14 on Tue Nov 04, 2014 2:12 am

    deepee99 wrote:Wayne,
    I can personally vouch for Troy's (tmadden) skills and attention to perfection.

    x 2 on Troy's skills.

    I got him to build and ship a PH-16 board for me last year so that I could upgrade my existing PH-15.
    Workmanship was spot on and he is a great guy to deal with ... very knowledgable and very helpfull.

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Tue Nov 04, 2014 6:25 pm

    A Troy built SP13/PH12 is headed my way. Thanks guys.

    Regards,
    Wayne

    deepee99

    Posts : 1333
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP13 preamp

    Post by deepee99 on Tue Nov 04, 2014 7:50 pm

    Yer won't be sorry. Congrats, and welcome to the booby-hatch.

    audiobill

    Posts : 270
    Join date : 2014-03-13
    Location : Philadelphia

    Re: SP13 preamp

    Post by audiobill on Tue Nov 04, 2014 8:19 pm

    Congrats, Wayne!

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Thu Nov 20, 2014 11:59 am

    Hi guys. Just a quick update. I'm enjoying the SP13/PH12. It sounds really nice and its dead quiet. I was surprised at just how good the phono stage sounds. Especially with some tube rolling. I guess I was expecting a bit of compromise when compared to the excellent phono stage in the Threshold preamp it replaced.

    So, with either of my sources (OPPO BDP95 for CD & SACD or Thorens TD126 / SME309 / ADC ZLM for vinyl) I can say that the SP13/PH12 bests my Threshold SL-10 in sound stage width/depth plus it has a more 'organic' midrange sound. These improvements are really noticeable on vocals.  At the same time it gives up nothing in dynamic range or frequency response extremes. Similar to my experience replacing a McCormack solid state amp with the ST-120, I was surprised that the SP13's deep bass response equals the Threshold's deep bass response.

    The one area that could be improved I suppose is the 'feel' of the stepped attenuator. In time, maybe I'll swap it for a Goldpoint or DACT or something similar. Not in any hurry though. Will probably turn my attention to some tube rolling  Wink BTW, I understand the choice of attenuator is a decision to keep the cost down so I'm not complaining, just passing on my observations.

    I'm really happy that I found this site and tubes4hifi. My music has never sounded better!

    Wayne

    TMadden

    Posts : 99
    Join date : 2011-12-22

    Re: SP13 preamp

    Post by TMadden on Thu Nov 20, 2014 2:22 pm

    Thanks Wayne for the excellent review, I'm glad you like it!
    Roy is currently supplying a 21 step attenuator with a lighter feel, and does offer an upgrade to
    Goldpoint/Elma also.
    What tubes did you settle on in the phono stage?

    Troy

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Thu Nov 20, 2014 3:27 pm

    Hi Troy,  Right now I have a pair of Amperex 6922 PQ orange label in the PH12. This weekend I will try a pair of Siemens E88CC A-frame (genuine made in Germany) and some Amperex 6DJ8 Bugle Boys. Which reminds me: Will a 7DJ8 work in the PH12?

    Regarding the attenuator, I was looking at the Goldpoint 47 step model but it only comes in 50K ohm. What effect would that have on the SP13?

    Lastly, SHAME ON ME  Embarassed  for not mentioning the outstanding work/craftsmanship you put into this preamp! And of course, Roy for the design!

    Wayne

    TMadden

    Posts : 99
    Join date : 2011-12-22

    Re: SP13 preamp

    Post by TMadden on Thu Nov 20, 2014 4:40 pm

    Wayne,

    I believe 7DJ8's will work fine. You must use a 100K attenuator, otherwise the frequency response of the
    PH12 will be affected.

    tubes4hifi
    Admin

    Posts : 1291
    Join date : 2008-11-30

    Re: SP13 preamp

    Post by tubes4hifi on Fri Nov 21, 2014 1:47 pm

    yes, 7DJ8s will work fine, and I've read great reviews on almost any good brand of PCC88 tubes,
    such as Phillips, Tungsram, and Pope, see more info here . . . .
    http://www.upscaleaudio.com/6922/

    deepee99

    Posts : 1333
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP13 preamp

    Post by deepee99 on Fri Nov 21, 2014 1:51 pm

    I've used 7DJ8s in 6922 holes with no problems, and NOS they're about half the price of 6922s for good ones. A 6.3V tap will run the filaments adequately.

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Fri Nov 21, 2014 3:30 pm

    Thanks Roy, Thanks Dave. I'll give the 7DJ8 a try after I roll through some tubes I already have in my stash.

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Wed Dec 03, 2014 9:40 am

    Still enjoying the preamp Very Happy  

    I ended up buying a Troy built stepped attenuator using an Elma switch with Vishay/Dale resistors. Installed it. Feels nice! As good as this preamp already sounds, I can't help but wonder what upgrading the coupling caps would do. I see that the Mundorf Silver/Oil is offered as and upgrade. Seems like a safe bet. I'm looking at the caps in C4 & C6 on the PCB and wondering if those should be upgraded with Silver/Oils also? Would there be any benefit to upgrading them?

    I'm not stuck on Mundorf. Also considering ClarityCap, Sonicap Platinum, etc.. Would love to hear from anyone who has already been down the cap upgrade road on a VTA preamp.

    Thanks,
    Wayne

    TMadden

    Posts : 99
    Join date : 2011-12-22

    Re: SP13 preamp

    Post by TMadden on Wed Dec 03, 2014 10:06 am

    Hi Wayne,

    C4 bypasses the B+ decoupling cap, there may be some small benefit in changing it.
    C6 is part of the power supply noise elimination circuit, probably no sonic benefit from changing that cap. Choice of output coupling cap depends on your system and your ears, so I won't offer any advice there.Question

    Jeff V.

    Posts : 34
    Join date : 2014-08-02

    Re: SP13 preamp

    Post by Jeff V. on Sat Dec 06, 2014 2:58 pm

    wgallupe wrote:Still enjoying the preamp Very Happy  

    I ended up buying a Troy built stepped attenuator using an Elma switch with Vishay/Dale resistors. Installed it. Feels nice! As good as this preamp already sounds, I can't help but wonder what upgrading the coupling caps would do. I see that the Mundorf Silver/Oil is offered as and upgrade. Seems like a safe bet. I'm looking at the caps in C4 & C6 on the PCB and wondering if those should be upgraded with Silver/Oils also? Would there be any benefit to upgrading them?

    I'm not stuck on Mundorf. Also considering ClarityCap, Sonicap Platinum, etc.. Would love to hear from anyone who has already been down the cap upgrade road on a VTA preamp.

    Thanks,
    Wayne

    Having built the SP14 preamp I would highly recommend the Russian Teflon FT-3 if you have the room.  Also consider Russian PIO, or the Audyn Copper capacitors.  
    I have the Clarity MR & FT-3 currently installed.  I find the FT-3 having better detail.
    The current attenuators Roy sells sound great in my opinion & have a nice feel.
    Enjoy your preamp!

    -Jeff

    tubes4hifi
    Admin

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    Re: SP13 preamp

    Post by tubes4hifi on Sat Dec 06, 2014 3:14 pm

    personally I think the K40Ys are comparable in sound to the SoniCap Premiums, and the Clarity Caps, but everyone who has the $$ for the expensive Mundorf silver-oils
    seem to think they are incredible, but it's all subjective, and to each ear it's own!! the K40Ys do need about 50 hours on them to start working well.
    Haven't heard the FT-3 teflons, but Teflon caps are supposed to be the best, bar none! Guess that's why V-caps go for $200-300 each piece.

    wgallupe

    Posts : 84
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: SP13 preamp

    Post by wgallupe on Sun Dec 14, 2014 10:20 am

    So, I have 'personalized' my Troy built SP13/PH12. See link for pics. For cap upgrades I ended up with Mundorf EVO Silver/Gold/Oil in the phono stage and Sonicap Platinum in the line stage. Other changes include an ELMA stepped attenuator, Goldpoint knobs, Amperex 6922 PQ tubes in the phono. The preamp came with nice RCA clear tops in the line stage.

    With about 15 hours on the new caps, this preamp is sounding fantastic. I hate to use an audiophile word like 'synergy' but I think that's exactly what I have stumbled upon with my total system. My analog source (Thorens TD126 Mk2 / SME309 / ADC ZLM) has never sounded this good. I can't believe how good the PH12 is!  

    Anyway, so excited I had to share...

    Wayne

    https://www.dropbox.com/sh/0o8lb0rikpcpoqj/AAC3n3MdzLQsIbVvznXMMRrba?dl=0

    TMadden

    Posts : 99
    Join date : 2011-12-22

    Re: SP13 preamp

    Post by TMadden on Sun Dec 14, 2014 11:33 am

    Wayne, thank you for the update. Obviously the SP13/PH12 has found a good home Very Happy
    Very nice upgrades, glad you are having fun with it! This is the second time in as many weeks a customer has commented on how the PH12 phono stage impressed them. It seems good NOS tubes are key to unlocking it's full potential.Very cool, thanks for the pictures! Nice work!

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