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    SP 14 Built

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    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    SP 14 Built

    Post by tiguan on Fri Aug 01, 2014 3:27 am

    I have been following this forum since April and digged into all SP14 builts. Meanwhile I have been following many alternative DIY Valve Pre kits. After long consultancies with my friends who are more experienced in tube world here in Turkey, I have decided to make SP14.
    Till now I made Jensen 1071 Speakers (of Troels Gravesen), Lampucera DAC (DAC kit from HongKong mod. by Lukas Ficus), BoozhoundLab Pacific Phono Pre, so I had some soldering skills without detailed electronic knowledge... All were figured out from manuals of parts...

    Finally week ago, I have completed my SP 14. Due to high transportation cost to Turkey, I supplied from Roy, PCB and its components. Hereby I have to thank to Roy. During all my DIY background, I had correspondances with many suppliers around World, Roy was the most responsive of them. He answered to all my questions (may be even to some silly ones  Very Happy, as its my first complicated project ).

    It was a week I have completed , left channel was ok but I could not get sound from right channel. Later I figured out,  that I have soldered signal cable and ground shifted. Then I controlled it is ok.Now just at the beginning I have very tiny deep crackles at right channel, which goes after warming up.Then deep silent kit. Smile

    http://s250.photobucket.com/user/yetkinturk/media/2014-07-23082446.jpg.html

    More detailed photos are at https://plus.google.com/105041940468126077194/posts/HKzZmAhkZ8d

    Maintarget

    Posts : 209
    Join date : 2013-02-10

    Re: SP 14 Built

    Post by Maintarget on Fri Aug 01, 2014 10:04 pm

    Very impressive build, cant wait to hear your listening impressions!

    audiobill

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

    Re: SP 14 Built

    Post by audiobill on Sat Aug 02, 2014 5:32 am

    That's beautiful, Tiguan. Enjoy!

    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    Re: SP 14 Built

    Post by tiguan on Sat Aug 02, 2014 11:34 am

    Thanks a lot. It was challenging for me. Sandpapering wooden part 5 times starting with no. 600 sandpaper, polishing and no.800 then polish up till no. 1200 sandpaper and final polish. Second challenging part was the front back and top covers. They are stainless steel so I had to define exactly all holes and openings make autocad drawing with a friend and give the workshop.
    Hopefully everything went well.

    As for sound. Honestly I did not get this performance from my system. Jensen speakers were waiting for this pre Smile
    Main differences were at low frequencies and high frequencies. Even with those Russian PIO s getting this performance was super. After burn in period, it will be a different world for sure.
    I have checked different tube second hand pre's. Do not want to name them, but even they were burned in already, did not gave this performance. We will compare in couple of months with some other tube pre kits (ebay) of my friends here.

    zx

    Posts : 194
    Join date : 2011-08-05

    Re: SP 14 Built

    Post by zx on Sat Aug 02, 2014 1:20 pm

    dynaco MK3s....


    Last edited by zx on Sat Aug 02, 2014 8:10 pm; edited 1 time in total

    zx

    Posts : 194
    Join date : 2011-08-05

    Re: SP 14 Built

    Post by zx on Sat Aug 02, 2014 1:21 pm

    Like the look..vary good work thanks for the pic...only thing i had that looks close was my old
    hhscott 355 pretuner ,299c,b,a...pure gold.... sweet like honey....i relly like the Big Tone of 6SN7...i have put some in the front end of dynaco MK3s....




    thanks for the site Bob.................

    Jeff V.

    Posts : 34
    Join date : 2014-08-02

    Re: SP 14 Built

    Post by Jeff V. on Sat Aug 02, 2014 7:09 pm

    Is that one of the Takman stepped attenuators from Ebay? Is the switch good quality? How do you like it?
    Nice build!

    -Jeff

    arledgsc

    Posts : 340
    Join date : 2012-11-30
    Location : SF Bay CA

    Re: SP 14 Built

    Post by arledgsc on Sat Aug 02, 2014 7:36 pm

    Very nice!   I like the look and the control extension shafts are really neat.   Congrats on a well planned project.

    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    Re: SP 14 Built

    Post by tiguan on Sun Aug 03, 2014 4:35 am

    Jeff V. wrote:Is that one of the Takman stepped attenuators from Ebay?  Is the switch good quality?  How do you like it?
    Nice build!

    -Jeff
    Thanks Jeff. Thats correct takman stepped attenuator from ebay. Full metal body very strong built, no crackle, no unwanted noise during volume up and down. I realy liked it. Additionaly due to well located in and outs no danger if ground touches signal or not. No need for a precaution.

    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    Re: SP 14 Built

    Post by tiguan on Sun Aug 03, 2014 4:37 am

    arledgsc wrote:Very nice!   I like the look and the control extension shafts are really neat.   Congrats on a well planned project.

    Thank you...

    deepee99

    Posts : 1332
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP 14 Built

    Post by deepee99 on Sun Aug 03, 2014 12:05 pm

    Tiguan yes, very nice.
    The 15 seconds of noise you hear at start-up is probably just the tubes warming up. I get a nasty open-ground sound from my SP-13 at about 8 seconds, then it goes away. An easy cure is to start the preamplifier first, wait a minute, then light the power amp(s).

    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    Re: SP 14 Built

    Post by tiguan on Sun Aug 03, 2014 3:30 pm

    deepee99 wrote:Tiguan yes, very nice.
    The 15 seconds of noise you hear at start-up is probably just the tubes warming up. I get a nasty open-ground sound from my SP-13 at about 8 seconds, then it goes away. An easy cure is to start the preamplifier first, wait a minute, then light the power amp(s).
    Thanks for advice

    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    Final experience

    Post by tiguan on Sun Sep 14, 2014 12:39 pm

    It has been almost 8 weeks that I have completed my SP14.
    I listen music everyday min 2 hour. Today morning I realised that I made the best thing by making this SP14.
    to fine tune thé system İ could not have a better opportunity. Just by changing 2 tubes you can jump to a different league.
    İ started by 4 quad matches Sylvania I guess 60's GTB Chrome tops. Friday İ received 2 matched RCA GT and 2 Raytheon GT s. Today morning İ took all 4 Sylvania GTB s and put 2 rca to the gain and 2 matched raytheon to the buffer.

    Opened jriver. And wow. My wife was telling why you are smiling so (which İ was not aware I do Smile ) It became a wonderful step for me.
    After this experience I ordered immediately 2 matched Sylvania vt231 from 40's which was in my watchlist at ebay. SP14 is a very responsive design. What you will do you get the result which is perfect...

    Here comes a question..Which position do you think that affect more, between gain and buffer. Sure need to be tried but as a start point if you will change Just 2 tubes which 2 you would replace gain or buffer.
    From the other thread relating microphonic, better tubes to gain. Microphonic to buffer.understood !!!

    But in my case, for better performance if microphonic is not an issue, better tubes to gain or buffer.

    deepee99

    Posts : 1332
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: SP 14 Built

    Post by deepee99 on Sun Sep 14, 2014 2:39 pm

    Better tubes to the voltage amplifier side, lesser tubes on the buffer side, in my opinion and experience with the 9-pin SP-13 and the M-125s.

    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    Re: SP 14 Built

    Post by tiguan on Mon Sep 15, 2014 10:49 am

    Thanks Deepee99 I got it. Will Be waiting vt231's

    tiguan

    Posts : 27
    Join date : 2014-07-23
    Location : Istanbul

    Tube alternatives

    Post by tiguan on Mon Nov 24, 2014 8:09 am

    It has been almost 4 months that I have been completed my Sp14 pre. Since then I have supplied some tubes, those are as follows;

    - 4 quad matched Sylvania GTB Chrome top

    - 2 matched Sylvania VT 231

    - 2 matched RCA 6SN7 GTB

    - 2 matched Raytheon 6SN7 GTB

    Based on my personal taste, my ranking is
    1. Sylvania VT 231
    2. Sylvania GTB Chrome top ( a price/performance tube, detailed, airy, big and seperated sound stage but not silky and not tube type romantic Smile I could not explain different way what I mean )
    3. RCA GTB (not bad but not as detailed like top 2 and even not as airy as Sylvania GTB Chrome top)
    4. Raytheon GTB (actually I did not like at all)

    BEST MATCH I had Sylvania VT231 at input and Sylvania GTB Chrome top as output.

    I wonder how 1578 and 5692 tubes will be.
    I am not a bass addicted guy and listen mainly Jazz trio, quartet ... groups , vocal albums and classical, so I am not after KenRad VT231 which is talked generally one of the best bass.

    I will be glad if other sp14 owners will share their opinions about tubes they have. Because not every tube acts the same in every tubepre with schematic design.
    Also did you check if rectifier tube makes difference... Because at some designs makes and some dont, as I read at some forums.

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