Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

Need help identifying the year of a SF DR...

12/13/2005 7:45 PM
SteveB Need help identifying the year of a SF DR...
I am considering trading my 1978 Marshall 100W half stack for a SF Deluxe Reverb. There is a faded stamp on the inside of the chassis that reads "Chassis Wiring M. Torres J1571" I think it is the letter "J" in the number sequence. The guy said it was an early '70's or '70, so I'm just double checking. He replaced the speaker with a Celestion G12H, & it sounds really nice.  
Any help would be greatly appreciated!  
12/14/2005 3:12 PM
Tom Phillips

I usually date these by transformer and Pot codes. Can you supply the numbers stamped on the transformers, the choke and a few of the pots? That will allow dating and give an idea if all are original. Always nice to see a picture of the inside of the chassis too. Also check to see if the baffle board is mounted on cletes or if it is dadoed into the sides of the cabinet. IIRC the dadoed baffle boards started showing up in late 1972 in the SF amps. All amps were not changed over at the same time. Note that the chassis and the cabinet could be from different years.  
I'd be glade to give you an evaluation of any phots you care to email to me.  
Good Luck,  
Book Of The Day The Ultimate Tone, Volume III by Kevin O'Connor
Have you ever wondered if there is a better way to build a Bassman, Champ, Plexi, an 800, AC-30, Bulldog or Portaflex? Or you wanted to build an SVT with off-the-shelf parts? How about a master-volume amp that doesn’t change tone with the master setting? Everything you need to know is right here, including: proper grounding techniques, wiring methods, and mechanical considerations. Eighteen chapters cover the “iconic” amps everyone knows and loves, with schematics and layouts for each, along with the technical history of the product. Eyelet-board and chassis-mounted tube socket construction is used throughout, for easy servicing and modding. TUT3 is very accessible even if you cannot fully read a schematic and is a "must have" if you are going to build an amp for your self.

Note: The Ampage Archive is an Amazon Associate site. A small commission is paid to the site owner on any qualified purchase made after clicking an associate link such as the one above.
12/16/2005 5:03 PM

I agree, I usually start with the pots. if you see a number on the back of the pot like 1377224, the 137 means CTS made the pot, and the 7224 means the part was made in the 24th week of 1974.  
If you look at a few date codes on pots, cap, trannys etc, you can get an idea of the age. Usually the amp will not be older than the most recent part in there, unless the part has been replaced at some point. And for that matter, most parts do not sit around for a couple years before going into amps.
12/17/2005 7:12 AM

The codes on pots and transformers are probably the best indicators of the amp's age.  
The serial number on the back of the chassis is helpful too. DR serials were roughly A31000 - A33000 in 1970, A33000 - A34500 in 1971, A34500 - A37000 in 1972 and A37000 - A39000 in 1973.
   Page 1 of 1