Ampeg SVT 1970's

[J M Fahey]

Like what?
Both have slant eyes and eat rice with chopsticks?

[soundguruman]

To answer the question, yes that's normal.

[Enzo]

Hmm, odd. I am at the moment working on a made in California fender, and there are certainly tons of USA made amps from Mississippi made by peavey. Last I checked those states were still in the USA.

[J M Fahey]

Not forgetting Mesa Boogies.
Last time I checked, Petaluma, California was *still* in tyhe USA.

[soundguruman]

Not forgetting Mesa Boogies.
Last time I checked, Petaluma, California was *still* in tyhe USA.

Yes, it's still "sort of" assembled in USA...

[Tage]

Hey back to the OP, I have looked into the schematics and channel 1 and 2 seem to be quite different. But my experiance with SVT's is limited to being pummled by them at concerts never worked on one...

http://www.webphix.com/schematic%20h.../svtpreamp.pdf

Channel one has two more gain stages and both are 12dw7's dc coupled to cathode followers so I would expect that to be the louder channel, but it also has the mid control stuff in there... I'd be checking those old 12dw7 to make sure they didn't get swapped out for somthing else.

[mac1amps]

The result of Ch 1's mid/ inductor network has somewhat of a "loading" effect on the signal which is why it may not have the same gain when set similar to Ch 2.......'like the man said, don't fret about the setting positions, plug in and play!!

[Frankthetankbass]

so i'm looking for a fuse for my 70's SVT it says 10A/250V and when i see them online i see 10A/250v 5mmx20mm and 10A/2500V 6mmx30mm. does anyone know which one is for this head? And as i understand it needs to be a slow blow as i understand.

[Enzo]

Those are physical size, nothing more. Th regular 1-1/4" fuse is 30mm, the smaller fuses like on imprt gear are 20mm. Get out a ruler and measure the length, it is either 20mm or 30-32mm. An American amp from the 1970s probably did not use 20mm fuses. I'd expect to find common inch and a quarter fuses.

[Frankthetankbass]

yes thank you -Measure what a great idea-silly me.....It's 1 1/4 thanks

[txstrat]

...both are 12dw7's dc coupled to cathode followers...

Cathode followers cannot provide a voltage gain higher than 1. The 2nd section of the 12DW7 even has a much smaller amplification factor (of about 20) than a 12AX7.
Therefore I would expect the first channel to be less loud.

Hence, the amps behavior is normal.

Hope this helps