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    SP-12 or SP-14

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    Leigh W

    Posts : 45
    Join date : 2013-04-02

    SP-12 or SP-14

    Post by Leigh W on Mon Oct 21, 2013 9:29 pm

    If anyone could chime in here it would be appreciated. I'm wanting to purchase one of Roy's preamps. I was thinking about the sp-12 because of the ability to add a phono stage, but also the sp-14 due to the higher quality sound and tubes. Has anyone compared these two preamps as to their sonic differences? I could forego the phono stage at this time and add an external one later if there is a nicer sound to the sp-14. Any opinions on the upgraded caps option would be appreciated as well. I have Bob's VTA-ST-120 now and was wondering how either of these preamps sound with this amp. I am currently using a Transcendent Sound Grounded Grid preamp and was wondering how Roy's preamps compare sonically. Speakers are Klipsch RF-82's. I'm also wondering how easily either pre is to build with the instructions provided. I've built lots of Heathkits, Transcendent Sound kits over the years as well as Bob's amp but all came with more comprehensive instructions. Opinions or thoughts anyone?

    Zimmer64

    Posts : 113
    Join date : 2013-01-29
    Age : 52
    Location : Switzerland

    Re: SP-12 or SP-14

    Post by Zimmer64 on Tue Oct 22, 2013 4:08 am

    I have Bob's ST70 and recently built the SP14. The sonics are stunning using decent vintage 6sn7's. I used mundorf SIO and gold / silver coupling caps and am very happy with them. I also added the goldpoint switches and attenuator. The build was straight forward. Roy provides the schematics, but no step by step manual like Bob does with his kit. If you have some experience under your belt, then that is no problem.
    I can definately recommend the SP14 and would do it again.

    Best

    Michael

    xlr8

    Posts : 68
    Join date : 2010-02-09

    Re: SP-12 or SP-14

    Post by xlr8 on Tue Oct 22, 2013 9:31 am

    I thought the SP 14 was pretty straightforward. If you have hardwired some Heathkit stuff in the past I wouldn't think you'd have any problem with it at all. Its layed out in a way that is easy to figure out without detailed instructions. So far mine is the best sounding preamp I've ever owned.

    tubes4hifi
    Admin

    Posts : 1292
    Join date : 2008-11-30

    Re: SP-12 or SP-14

    Post by tubes4hifi on Tue Oct 22, 2013 10:55 am

    quote from my SP14 webpage:
    Let me start with an introduction to this product. This is a major upgrade with many refinements to my previous best SP12 preamp.
    This preamp is NOT intended for the casual listener. This preamp is for those who are NOT satisfied with a $3000 preamplifier.
    This preamp IS intended for those DIY builders who may have already experienced my SP12, or who want the best preamplifier kit available at any price.
    This preamp IS intended for those who want a $6000 preamp but who can't afford that. This preamp built as a kit will total under $1000,
    or I can supply it custom built and ready to use.
    Strong statements? YES! Do I stand behind them? YES!


    No one has ever had anything less than super praise for the SP14 preamp. It's performance has to be heard to be believed.
    Same comments apply to our new PH16 phono preamp. Customers are giving away their $2500++ phono preamps to get this at under $700.

    Leigh W

    Posts : 45
    Join date : 2013-04-02

    SP-12 or SP-14

    Post by Leigh W on Tue Oct 22, 2013 8:56 pm

    Thanks for the reply's on the SP-14. I think the SP-14 is the way I will go. I just need to put together my upgrade package and get back in touch with Roy. A couple more questions I do have and that is, are the Gold Point attenuators worth the extra cost compared to what comes standard with the kit? and is there a sonic difference between the Mundorf caps versus the K40Y-PIO caps? Thanks all for your input on this topic. Cheers...Leigh

    Zimmer64

    Posts : 113
    Join date : 2013-01-29
    Age : 52
    Location : Switzerland

    Re: SP-12 or SP-14

    Post by Zimmer64 on Wed Oct 23, 2013 6:06 am

    I do have no experience with the pio's in the SP 14. I use 2 different mundorfs.

    Here is my subjective impression of the difference in sound between the Silver/Oil vs. the Gold/Silver Mundorf's after having listened to them for a few months now.

    The S/O are smoother with a little less top end. High frequencies are somewhat down vs. the G/S. The difference is not huge, but noticeable in direct comparison. Bass and mids are practically the same.

    Imaging wise the sound stage of the G/S is clearly wider and deeper. Classical orchestras or small Jazz combos are equally well reproduced.

    On good recordings I definitely prefer the G/S. The S/O are a bit more forgiving with bad recordings as they seem to round shouty edges a little bit off. They may also be the better choice if one has brighter sounding components in their setup.

    Best

    Michael

    Avinunca

    Posts : 26
    Join date : 2012-04-15
    Age : 59
    Location : Shrewsbury England

    Re: SP-12 or SP-14

    Post by Avinunca on Wed Oct 23, 2013 3:35 pm

    I built the SP14 having previously built the PH15 phono. I found it straightforward and I am very pleased with it (and the PH15). In the SP14 I used 12SN7 tubes as they seemed somewhat cheaper. Needed to change the two pairs of resistors that set the heater voltages to 12V.
    I used a Khozmo stepped attenuator which I imported from Poland. I used Russian PIO caps - very inexpensive.
    Happy building!


    Michael


    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Consider an AP-13 as well

    Post by deepee99 on Thu Oct 24, 2013 6:30 am

    Perhaps this is off-topic if you're determined to have octals, but all the same praise heaped on the SP-14 very accurately describes the nine-pin SP-13 as well. I have had an SP-13 for about a year, (felt a bit wimpy about building it so enlisted Troy Madden, a compatriot of Roy's, to do the soldering), and about a month ago came across a slightly used quartet of side-getter RCA "clear-top" 6CG7s for it and plugged them in. Nirvana! Believe me, there is nothing sweeter and clearer than this combination for a line pre-amp, bazillion-dollar ARCs and Macs included. The sheer variety of both current production and NOS 6CG7/6FQ7 tubes out there invites experimentation and tube-rolling, too, although now that I've heard the RCAs in this critter, the other tubes are for sale to finance another couple of four-somes, which should get me well into my dotage. And I've got a PH-16 on the way . . .

    Leigh W

    Posts : 45
    Join date : 2013-04-02

    Re: SP-12 or SP-14

    Post by Leigh W on Thu Oct 24, 2013 5:27 pm

    Was just wondering if anyone has compared the sp-14 with the Transcendent Sound grounded grid. That's what I'm using now. Cheers...Leigh

    tubes4hifi
    Admin

    Posts : 1292
    Join date : 2008-11-30

    Re: SP-12 or SP-14

    Post by tubes4hifi on Thu Oct 24, 2013 5:52 pm

    yes, have compared that to just about every preamp I've ever made, not even close in performance to any of them.
    Any of the SP12-13-14 would be a HUGE improvement.
    Here's a photo taken four years ago . . .  .


    Bob Latino
    Admin

    Posts : 2414
    Join date : 2008-11-26
    Location : Massachusetts

    Re: SP-12 or SP-14

    Post by Bob Latino on Thu Oct 24, 2013 6:06 pm

    Hi Leigh,

    When Roy first designed the SP series of preamps the SP-8 was the first one which dates from 2009. Before the SP-8 preamp kit went into production Roy sent me a sample. I had it here for 3 weeks to evaluate the sound in relation to a number of preamps that I had on hand here. All evaluation was done with my own personal VTA ST-120 amp. I also had here a few years earlier a Transcendent Grounded Grid and although I did not have the Transcendent preamp on hand at the time, I remembered well it's sound. The original SP-8SE was better IMHO than the Transcendent Grounded Grid preamp. The bass on the SP-8SE went lower than the GG preamp and the tonality (instuments just seemed more real) and soundstaging (definitely wider on the SP-8SE) was better.

    The newer SP-14 is an upgrade to the original SP-8SE and no doubt is an improvement on SP-8SE's circuitry. My original 2009 review of the SP-8SE is at the link below ..

    SP-8SE review

    Bob

    Leigh W

    Posts : 45
    Join date : 2013-04-02

    Re: SP-12 or SP-14

    Post by Leigh W on Thu Oct 24, 2013 6:56 pm

    Thank you Bob for sharing that info concerning the GG. I will be in touch with Roy over the weekend about purchasing the SP-14. I will also be in touch with you again regarding a second VTA-ST 120. I asked you once if the VTA-120 was bridgeable and you recommended bi-amping two ST-120's instead. This is what I plan on doing. In the mean time I have bi-amped my Klipsch RF-82's with my Marantz power amps and they sound fantastic with two amps per speaker. Thanks again to everyone who has helped here. Cheers....Leigh

    ruffian

    Posts : 43
    Join date : 2010-02-26

    Re: SP-12 or SP-14

    Post by ruffian on Sat Oct 26, 2013 1:33 am

    The Goldpoint pots are real smooth, their feel alone is almost enough to justifytehm. I can't comment on them sonically as I have never compared them against something else side by side. If you have never had the need to adjust the balance on your existing gear then I suggest you ditch the L/R gain pots all together. Eliminating them will also make a single Goldpoint look like a better option as far as cash outlay.

    You might want to consider running with one set of caps. Unless you are bi-amping one of the pairs will always be dangling in the breeze. I put the Russians and Mundorfs in mine. I can't really tell the difference as I can't A/B them on the fly and whatever difference there might be is lost on me by the time I turn things off, climb behind my rack, change cables and start it up again.

    It is a fun kit to customize and then build, enjoy.

    xlr8

    Posts : 68
    Join date : 2010-02-09

    Re: SP-12 or SP-14

    Post by xlr8 on Wed Nov 06, 2013 9:58 am

    I thought about going with different selector switch and volume, but after playing around with some different tubes, those 2 items have taken a back seat for awhile. As much as I appreciate Roy seeking out good modern reproduction tubes to sell with his creations, I have found the biggest sonic benefit comes from good ole' NOS tubes. I have wired in both Mundorf S/O and the Russian PIO's in my SP14. For my system, I have settled on the Mundorfs. They seem to have an extra bit of sparkle that the PIO's lack. But again, I feel that the tubes far outweigh any perceived benefit that caps, switches or attenuators can provide. When I installed my SP14 into my mix, the difference was immediate. A/B switching between caps, not so much, but replacing the new production Tung-sols with some vintage Sylvania green labels? OH MY GAWD!

    TMadden

    Posts : 99
    Join date : 2011-12-22

    Re: SP-12 or SP-14

    Post by TMadden on Wed Nov 06, 2013 10:51 am

    I have had the same experience with my SP9 octal, and my PH16. I have converted my SP9 to use 6SN7's, when I tried a set of vintage Sylvania Chrome Domes, it was a major improvement. Let's just say I'm done rolling tubes in the SP9! Same thing with my PH16, but even more dramatic, when I dropped in a pair of Amperex Bugle Boys in the first two sockets, it went from sounding great, to sounding "real"! I catch myself just looking at the speakers, almost in disbelief that the sound is so real and present with a good LP. Man I love tube gear, what fun! Can't wait for my RCA clear top 6CG'7 to get here, to try in the output stage of the PH16!

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP-12 or SP-14

    Post by deepee99 on Wed Nov 06, 2013 11:34 am

    TMadden wrote:I have had the same experience with my SP9 octal, and my PH16. I have converted my SP9 to use 6SN7's, when I tried a set of vintage Sylvania Chrome Domes, it was a major improvement. Let's just say I'm done rolling tubes in the SP9! Same thing with my PH16, but even more dramatic, when I dropped in a pair of Amperex Bugle Boys in the first two sockets, it went from sounding great, to sounding "real"! I catch myself just looking at the speakers, almost in disbelief that the sound is so real and present with a good LP. Man I love tube gear, what fun! Can't wait for my RCA clear top 6CG'7 to get here, to try in the output stage of the PH16!
    I would concur that tube choice is critical to one's listening satisfaction. The danger is that you can end up with a tube inventory that cost more than the actual equipment did affraid 
    I have an SP-13, which is the 9-pin version of the octal SP-14, and had the same experience TMadden describes when I rolled in a quartet of NOS RCA 6CG7 clear-tops. All of a sudden the sound was just THERE and I put the screws back into the lid after a year of rolling. Even fiddling with different rectifier tube options in the M-125s will produce noticeable improvements/degradations of the signal, though more subtle perhaps than the differences in output tubes. I also have the PH-16 and treated myself to a matched pair of Bugle Boys in V1 and V2 (Amperex 7DJ8s) and cleartops in V3 and 4. Wow!

    Tube Nube

    Posts : 643
    Join date : 2008-12-06
    Age : 53
    Location : Calgary, AB

    Re: SP-12 or SP-14

    Post by Tube Nube on Wed Nov 06, 2013 7:55 pm

    Leigh, I can confirm Bob's recollection.

    I still have mt TS grounded grid, my SP 8, and my current SP 14 ... With it's one of a kind Pacific Northwest mossy green anodized face plate.

    The SP8 was much better than the GG. The Sp14 is very much better again. Fluffy blond highs, seductive shapely and vigorous in the middle bits, full,and firm in the bass.

    Sorry, i havent mastered audiophile-ese. ;-)

    Seriously, the difference is huge and immediately unmistakable from the opening bar of any opening tune. You wont be sorry if you get the 14, but you'll regret it if you dont. I promise.

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