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A box arrived.

No, no pilot light with these. I guess all those tubes lighting up is enough. :biggrin:
HA,, OK,,, well I put a pilot on everything, even the 811 amp, just to balance the layout,... Its on the opposite side from the switch, same color as the tube glow heaters but really not needed with those big bulbs !!!
 
I was able to get a little more done today on one of the amps. I'll have some more questions about the NFB when I get that far.
 

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These have same dang heavy iron. One of these probably weighs close or the same as the ST-70.

I assume you mean the entire ST70 amp and not PT of one versus the other.

The amp is looking good. Cannot wait for you to share your experience as far as the sonic qualities. I am also interested to read your thoughts on the Russian K42 PIO caps. I think in the past Bob provided the K40s.
 
I assume you mean the entire ST70 amp and not PT of one versus the other.

The amp is looking good. Cannot wait for you to share your experience as far as the sonic qualities. I am also interested to read your thoughts on the Russian K42 PIO caps. I think in the past Bob provided the K40s.
I used them in my ST-70. I'm not sure I can really tell much difference in most caps. There are a few I have, like the Super Z's.
 
are those blue glass ? I dig it.
Yes. Tubes and More had them on sale several years ago for a couple bucks cheaper than the clear glass. They have been out of stock for a over a year now. Maybe they aren't made anymore? And what I find now on ebay are more expensive than they use to be. I would like to find another quad of them though.
I won't buy off ebay.
 
I have the utmost respect for the VTA amps, but why in the world on a "new construction" amp can't they fabricate a way to not expose the driver board on their standard chassis? It's not like this is a clone of a Mk III so there seems to be no need for exposing the board in the same way. Seems it wouldn't be much effort to mount the board on standoffs underneath and poke the tubes through two holes in the top of the chassis. But I digress.

Just one of my pet peeves I guess.

On with the build...
 
I have the utmost respect for the VTA amps, but why in the world on a "new construction" amp can't they fabricate a way to not expose the driver board on their standard chassis? It's not like this is a clone of a Mk III so there seems to be no need for exposing the board in the same way. Seems it wouldn't be much effort to mount the board on standoffs underneath and poke the tubes through two holes in the top of the chassis. But I digress.

Just one of my pet peeves I guess.

On with the build...
Funny you should bring that up. Here is what I ran into today while installing the driver board. Instructions say to install one nut between the board and chassis, then another nut to secure the board, and a locking nut over that. Not good. I noticed while I was securing the nuts on the bottom of the board one of the resistors close to the edge was being pinched between the board and chassis. Looking closer even the slightest bit of solder on top of the solder pads around the edge of the board was very close, or touching the chassis. I was being very careful not to get too much solder on top of the board in these areas. The pinched resistor was right where it was supposed to be too. So I used two nuts between the chassis and board and secured the board with the locking nuts only. This allowed the proper spacing. They do sell plexy covers for the boards now for extra. I put one on my ST-70. But Roy wants $50 for a pair for mono blocks. That's a lot for two small covers with a couple holes in them.
 
I'd probably just order 4 plastic standoffs that you use to mount a motherboard to a PC chassis. Drop the board down by 1/2 inch. The tube sockets will still be easily accessible. Just a thought.
 
I'd probably just order 4 plastic standoffs that you use to mount a motherboard to a PC chassis. Drop the board down by 1/2 inch. The tube sockets will still be easily accessible. Just a thought.
I didn't have this problem with the ST-70, So It didn't even enter my mind until I noticed the problem. I looked through all my standoffs and no plastic ones that would work. Using double nuts worked out fine though.
 
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