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ST35 Reborn!

PostPosted: Mon Aug 12, 2013 3:31 pm
by corndog71
So I completely dismantled my ST35 with DIYTube driver and EFB mods and came up with a "new" layout. Still working out some bugs but these things happen in 8+ hour marathon soldering sessions. I'm really happy with the new layout and think it will be much easier to measure and tweak. Not to mention I think it looks much better.

Here was my dream. I drew this on my ipad using Paint by 53.
http://i576.photobucket.com/albums/ss20 ... 5229b3.jpg

Next thing you know I got a box and started measuring...
http://i576.photobucket.com/albums/ss20 ... 8fb8a4.jpg

A ton of work later I end up with this...
http://i576.photobucket.com/albums/ss20 ... 87580a.jpg

The IEC receptacle is kinda temporary because I have a hard time cutting square holes in aluminum.
http://i576.photobucket.com/albums/ss20 ... cfb69f.jpg

It's challenging getting a good shot of the inside.
http://i576.photobucket.com/albums/ss20 ... faa030.jpg

Here's a close up of the tube sockets.
http://i576.photobucket.com/albums/ss20 ... 3676a4.jpg

Power supply and EFB.
http://i576.photobucket.com/albums/ss20 ... fffd80.jpg

Re: ST35 Reborn!

PostPosted: Mon Aug 12, 2013 3:36 pm
by Shannon Parks
Nice pix, Corndog. Love that artist rendering - it would make a great t-shirt!

Shannon

Re: ST35 Reborn!

PostPosted: Tue Aug 13, 2013 8:39 pm
by corndog71
I appreciate that, Shannon. You might be right about that T-shirt idea.

Re: ST35 Reborn!

PostPosted: Mon Aug 26, 2013 3:47 pm
by corndog71
Some say you need them. Some say you don't. I decided to include cathode fuses. I use Littelfuse 160mA slow blow high-breaking ceramic fuses based on recommendations from a reknown tube amp manufacturer.

http://i576.photobucket.com/albums/ss20 ... d492fa.jpg

http://i576.photobucket.com/albums/ss20 ... 0fc6ec.jpg

Just got a matched set of EL84's from RAM labs. I'll report back with the verdict.

Oh and since Shannon mentioned using 6-volt tubes in the new Rev E, I also picked up a 6CG7 to try out in the V2 spot. (Yes, I know about changing the heater wires.)

Re: ST35 Reborn!

PostPosted: Tue Aug 27, 2013 1:00 pm
by corndog71
The RAM labs tubes are no joke. I've tried matched sets by Valve Art and new issue Genalex and while they sounded pretty good they never came close to the depth and transparency I'm getting from the matched Sovteks from RAM. Definitely recommended!

Re: ST35 Reborn!

PostPosted: Sat Aug 31, 2013 3:22 pm
by corndog71
http://i576.photobucket.com/albums/ss20 ... dee408.jpg

I have all RAM tubes in now.

V1 - 5751 with matched gain
V2 - 6CG7

It sounds utterly sublime. RAM tubes may seem a bit pricey but I can't recommend them enough.

Re: ST35 Reborn!

PostPosted: Tue Oct 08, 2013 9:00 am
by corndog71
I finally got around to updating my power connection. I decided to try something different (as usual) and put in the new Neutrik powerCon connector.
I really like this connector. When it locks in place you can just feel it's a solid connection. Yeah, it's not universal but that's ok. I made this for me.

http://i576.photobucket.com/albums/ss20 ... 0b02c3.jpg

http://i576.photobucket.com/albums/ss20 ... 779575.jpg

http://i576.photobucket.com/albums/ss20 ... ea8ed0.jpg

http://i576.photobucket.com/albums/ss20 ... 65bdbb.jpg

Now if only there was an easy but still good-looking way to label everything.

Re: ST35 Reborn!

PostPosted: Sat Oct 19, 2013 9:36 am
by corndog71
http://i576.photobucket.com/albums/ss20 ... 6660f9.jpg

Trying some different caps out. Clarity Cap MR series .1uF
Sounds pretty good! Part swaps are a lot easier with this layout.

EDIT: The Sonicaps are NOT going back in!

Re: ST35 Reborn!

PostPosted: Mon Nov 18, 2013 2:47 pm
by corndog71
I also used that Paint app for designing the guts.
(This pic shows the V2 heaters wired for 12A*7 type tubes. For 6CG7 you would simply wire the heaters the same as the EL84 tubes.)

http://i576.photobucket.com/albums/ss20 ... 3f8c70.jpg

http://i576.photobucket.com/albums/ss20 ... a4a521.jpg

Here's a sketch of the EFB layout. The big power supply cap connections are overlapping.

http://i576.photobucket.com/albums/ss20 ... e4e81f.jpg

Re: ST35 Reborn!

PostPosted: Wed Feb 19, 2014 3:52 pm
by corndog71
I'm almost finished with my latest project. I got Bob Latino's ST-120 (basically a KT88 version of the ST70) kit and put my own little spin on it. It is the big brother to the amp in this thread.

http://dynacotubeaudio.forumotion.com/t ... -vta-st120

Both of my "babies".

http://i576.photobucket.com/albums/ss20 ... ntpynb.jpg

Re: ST35 Reborn!

PostPosted: Thu Jul 24, 2014 10:13 am
by carpenter
Beautiful job! You're inspiring me to build an ST-35. I have a bid on an old unit on eBay. I hope to get some affordable parts so that I can do the upgrades that you're doing. Thanks for sharing your works of art.

Re: ST35 Reborn!

PostPosted: Thu Sep 25, 2014 5:13 am
by SteveK
It is a beautiful job. I have a couple of Hammond 1650Fs that would be perfect for this. Is there a schematic for the wiring? Parts list?

I also like the roomy chassis.. where did you get it from?
Steve

Re: ST35 Reborn!

PostPosted: Thu Sep 25, 2014 12:34 pm
by Auricle
I also used that Paint app for designing the guts.
(This pic shows the V2 heaters wired for 12A*7 type tubes. For 6CG7 you would simply wire the heaters the same as the EL84 tubes.)


I know I am commenting about a post that is nearly a year old - I am relatively new to the forum.

Your renderings are brilliant! T-shirts? Sure, I'd probably buy one, but I think your renderings would not be out of place at MOMA, especially when entitled "ST35 guts" ;-)

Regards,
Auricle

Re: ST35 Reborn!

PostPosted: Fri Sep 26, 2014 5:09 am
by Shannon Parks
Auricle wrote:Your renderings are brilliant! T-shirts? Sure, I'd probably buy one, but I think your renderings would not be out of place at MOMA, especially when entitled "ST35 guts" ;-)


I commissioned Corndog to do a Budgie phono preamp for me. I love it!

Shannon

Re: ST35 Reborn!

PostPosted: Fri Sep 26, 2014 5:35 am
by WA4SWJ
Now that definitely belongs on a T-shirt!!!

Nice job!