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    SCA-35 Rebuild

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    Danner

    Posts : 16
    Join date : 2012-09-27

    SCA-35 Rebuild

    Post by Danner on Wed Feb 14, 2018 11:23 am

    New member, first post.

    Here are some photographs of a chassis-up rebuild I just completed on a SCA-35 Dynaco.





















































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    pichacker

    Posts : 65
    Join date : 2016-08-01
    Age : 54
    Location : Near to London - UK

    Re: SCA-35 Rebuild

    Post by pichacker on Thu Feb 15, 2018 4:55 am

    Hello and welcome. I cannot see your pictures.
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    Dave_in_Va

    Posts : 244
    Join date : 2013-04-02

    Re: SCA-35 Rebuild

    Post by Dave_in_Va on Thu Feb 15, 2018 10:39 am

    Welcome!
    Congrats on the restoration. I bet it's a nice amp.
    Did the Brent Jessee tubes work?
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    Danner

    Posts : 16
    Join date : 2012-09-27

    Re: SCA-35 Rebuild

    Post by Danner on Thu Feb 15, 2018 2:35 pm

    Dave_in_Va wrote:Welcome!
    Congrats on the restoration. I bet it's a nice amp.
    Did the Brent Jessee tubes work?
    Yes, the tubes work well.
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    Danner

    Posts : 16
    Join date : 2012-09-27

    Re: SCA-35 Rebuild

    Post by Danner on Thu Feb 15, 2018 2:39 pm

    pichacker wrote:Hello and welcome. I cannot see your pictures.

    Sorry for the troubles. Perhaps try to paste this URL to your browser address line:

    http://www.dlaab.com/photo/sca.za.jpg

    The file names are all the same, changing only the .za. within the range from .b. through .z., and then .za. through .zc.

    Good luck.
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    WLT

    Posts : 54
    Join date : 2013-07-13
    Location : Rochester NY

    nice

    Post by WLT on Wed Feb 21, 2018 12:26 pm

    great work. My SCA 35 is old but rebuilt and working well. My first one was in 1971 and is the reason I have the Dyna collection I do today. Enjoy with a nice set of speakers and life is good.
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    Peter W.

    Posts : 1034
    Join date : 2016-08-07
    Location : Melrose Park, PA

    Re: SCA-35 Rebuild

    Post by Peter W. on Wed Feb 21, 2018 10:00 pm

    Love the rebuild - and in full tear-down detail.

    Preference, *!NOT!* criticism - I would have preferred grommets on the chassis penetrations. Give that I am a belt/suspenders/Velcro type of person when it comes to these things.

    Once again, excellent work!
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    Danner

    Posts : 16
    Join date : 2012-09-27

    Re: SCA-35 Rebuild

    Post by Danner on Wed Feb 21, 2018 10:44 pm

    I also built one of these in 1971, as a boy in school, it was my first *good* stereo. I had a pair of Realistic Electrostatic 2a's and a BSR turntable. Traded it for a Gibson guitar and went off to college.

    Back in the day, there was a Hi-Fi clinic in Chicago where they would run IM and THD on your amp. My little Dynaco did a respectable job, but a good friend of mine had a Sansui transistor amp that really produced almost no distortion. A little humble pie right there. Also, Paul Klipsch was there and I got to meet him and talk about horn speakers with him. That's something I'll always remember.

    I must say, I thoroughly enjoyed this rebuild, and have really enjoyed listening to this. It's now the main stereo in the family room. My speakers now are late model Klipsch Cornwall II's. Running a AT120 turntable. Looking to get the new AT-LP7 whenever it becomes available.

    Cheers.

    jimzim429

    Posts : 5
    Join date : 2017-02-08

    Re: SCA-35 Rebuild

    Post by jimzim429 on Fri Mar 02, 2018 11:08 am

    Danner,

    I am also from Chicago on the south side. We had EZ Teltronics run by Paul and Jerry on 59th and Mozart. They were the McIntosh dealer and had clinics until they closed in the 90's. Where was the event you went to get the meet Paul? I went to a Marantz clinic in '72 on the northwest side in a suburb I recall.

    jz

    Dynaco_wjw

    Posts : 12
    Join date : 2013-11-28

    Re: SCA-35 Rebuild

    Post by Dynaco_wjw on Sat Mar 03, 2018 4:02 pm

    Very Nice Danner.

    Is the chassis the old chassis with cadmium? I don't know if you cleaned it after you restored it? Better to clean because your fingerprints will become very ugly grey.

    Did you choose to keep it completely original? Otherwise I suggest new boards from Dave Gillespie (tronola.com). Also a new power board with EFB. You can clearly hear the difference.

    Did you use new potentiometers?

    I restored 2 SCA-35. Still have 4 left to restore.

    Your front is as new. This is wonderful.
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    Danner

    Posts : 16
    Join date : 2012-09-27

    Re: SCA-35 Rebuild

    Post by Danner on Mon Mar 05, 2018 2:41 pm

    jimzim429 wrote:Danner,

    I am also from Chicago on the south side.  We had EZ Teltronics run by Paul and Jerry on 59th and Mozart.  They were the McIntosh dealer and had clinics until they closed in the 90's.  Where was the event you went to get the meet Paul?  I went to a Marantz clinic in '72 on the northwest side in a suburb I recall.

    jz
    Trying to fire-up the Way-Back Machine™️. IIRC, we met Paul at a Hi-Fi show at a Marriott hotel in the north suburbs of Chicago. There were multiple vendors, and Klipsch had a good sized suite, even sowing a Pair of Belle Klipsch. The Amp testing event was at a Hi-Fi dealer in the same area, but I can't remember the name/place. These both occurred in 71-72.
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    Danner

    Posts : 16
    Join date : 2012-09-27

    Re: SCA-35 Rebuild

    Post by Danner on Mon Mar 05, 2018 2:49 pm

    Dynaco_wjw wrote:Very Nice Danner.

    Is the chassis the old chassis with cadmium? I don't know if you cleaned it after you restored it? Better to clean because your fingerprints will become very ugly grey.

    Did you choose to keep it completely original? Otherwise I suggest new boards from Dave Gillespie (tronola.com). Also a new power board with EFB. You can clearly hear the difference.

    Did you use new potentiometers?

    I restored 2 SCA-35. Still have 4 left to restore.

    Your front is as new. This is wonderful.
    Thanks.

    I did a lot of cleaning as I disassembled it. The chassis is a later unit, guessing 69-71 vintage. I can tell because the knobs weren't the older die-cast, but the later extruded aluminum.  They age much better and match the face plate finish too.  The frame is original cad-plated steel.

    Old potentiometers and PEC's, although the HUM pots were changed at some point.  OEM output transformers, but the power transformer had also been changed.

    I bought the Gillespie boards but decided against using them.  I already had a good set of 7199's and when the Dynaco can-capacitors tested good, I shelved the after-market PS board (SDS I think it was) and also decided to keep it as OEM as I could.  Even kept the original "suicide" power cord LOL.  This amp was actually put together from two SCA-35 part sets.

    I love this amp very much.

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