AMPEG SVT Blueline - NAD - Need Expert Feedback! :)

Unless it's a 6146b SVT converted to 6550's, I'd guess 71.

 

Looks like a '71 to me too.

Looks like a past owner swapped out the fan for one in the wrong size?

The microphonic tube could be the 6C4 preamp one, very common as was the case with my '72.

 

Agreed the microphonic tube is likely the 6C4. I have about 10, they're all microphonic to varying degrees. Those GE6550s are nice to have. Given the two prong plug I'd guess a cap job is in your future. Congrats on the amp.

 

It looks great.
SVTs are fantastic, I don't see myself owning one again though.
I admire people who in this day and age still have the dedication it takes to carry around 80 pounds of tubes.

 

The only hard part is lifting it on top of the cab and off again. Otherwise the moving isn't too bad.

 

It is, however while I don't know what a .67 ohm difference makes, I do know what a 2:1 difference makes, and I don't like it. Makes the head sound tighter and a little more compressed to my ears. But Bill Hughes, the inventor of the SVT, has said those trannies can easily handle up to a 2:1 mismatch.

 

Very nice. Not sure about the Hammond transformer. On the back, the clutch head screws on the cord winders are original, the other Phillips head screws, not original.

'71 to me three. The cabinet with the sharp edges looks like a 69 or 70.

I've given up doing that long ago. Nothing wrong with getting some help.

 

Get it converted to 3 prong for safety sake. I would not worry too much about cleaning the boards (very Higg voltages in there that do not go away when you unplug the amp) you could end up causing yourself problems. But clean all the 1/4" jacks with deoxit.

 

I use a product called safety wash (1 liter liquid available at http://www.mouser.com). It is strong enough to clean but not so strong that it removes color bands and lettering from components. Be careful though. I use a combination of Q-Tips, round flat cotton makeup removing pads (both available at a drug store), and pipe cleaners (from a place that sells smoke related stuff). Deoxit is good for cleaning pots, jacks, tube sockets and pins, any metal to metal contacts.

Before working on the amp, you need to ensure that the electrolytic caps are discharged. You can get a bad shock if they are not drained.

There's some additional info here in the PF Wiki. Click on the link for discharging the caps before you begin.

 

There was a band in Toledo called Rockestra back in the '70s. If I recall correctly, Tim Chandler was the bassist.

 

nice score....

 

How good is that. Some of the 1970 amps had the 6146B tubes so you must have one of the earliest ones with the 6550A tubes.

Enjoy your amp!