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Posted: **Mon Jun 29, 2009 6:01 pm**

I built a Triode Electronics ST-70 Kit for my friend on Saturday.
He wanted the stainless steel chassis, and I wanted something
quick and easy, all in one box. Triode did a nice job of packing
everything tightly in a small, heavy carton. I did the mechanical
work first, then put the circuit boards together, and then wired it
all up. I'd say it took about 4 hours. It biased right up and
sounds great.

Here are some pix:

Bigger versions and more stuff on my website at http://tmamps.com

Posted: **Mon Jun 29, 2009 10:26 pm**

Geez, you sure are fast, 4 hours!!!

Nice job,
Sal

PS: I would have gone stainless steel....

Posted: **Tue Jun 30, 2009 2:53 pm**

I realize that there isn't much of a need for the two front-panel power sockets or the stereo-mono switch that were included on the original ST70. But that front panel looks naked to me.

Well, actually, the front-panel sockets are handy to use as a voltage take-off point for bias adjustment.

Posted: **Tue Jun 30, 2009 4:11 pm**

That's a great looking '70 Tom!

I like the Triode chassis layout with the IEC connector, revised front panel, etc, I just wish it was shiny like the Dynakit chassis.

Posted: **Tue Jun 30, 2009 5:34 pm**

Looks great! How does the Triode EF86/12AU7 board sound as compared to the original or Shannon's boards? I like the new chassis design, nice and clean, and updated from the vintage arrangement.

I have tried the Triode board in a "maverick" ST70 clone I built several years ago, it was in a large (17 X 10) stainless steel chassis that Triode sold for a short while, and all the iron was the infamous "Hand Wound Transformers" variety. Back then I called it the "Stainless Steel Behemoth". It sounded OK, but I would SWAG that the HWT ieon held its performance back quite a bit... (sick)

Looks like you may be close to challenging tthe laws of physics and Newton's gravity, with perching it on the corner of the deck railing, with all the weight hanging over the back...

/ed B

Posted: **Tue Jun 30, 2009 5:55 pm**

TerrySmith wrote:I like the Triode chassis layout with the IEC connector....

I hadn't noticed the IEC power connector. Is the chassis connected to the power system ground conductor? If so, I wonder if that might cause ground-loop issues depending upon the power wiring of any preamp, turntable, or other source?

(The original ST-70 circuit was set up for a 2-conductor line cord. I built a modern clone that had the chassis grounded through a 3-conductor line cord. I ultimately had to disconnect the chassis ground connection to use with my other audio components.)

Posted: **Tue Jun 30, 2009 9:26 pm**

The stainless chassis look nice, they do pick up fingerprints pretty
quickly, but then again so do the chrome ones.

I left my normal "test CD" in the car, and didn't listen as critically
as I usually do ... but the board sounds good.

I typically ground the IEC connector to the chassis right at the
mounting with a serrated ground lug. No hum so far, although
my system doesn't have any Cable TV (did I mention I HATE COMCAST)
connection, so no ground loops here. I did connect my computers
RS-232 port to a Polk XM tuner (before Mel Karmazin screwed up
XM and I cancelled) and that brought hum in ... well to whatever
amp I had hooked up at the time. So yeah, tricks are often
necessary to keep things quiet.

... tom