Build date on a Silverface Fender

[tomteriffic]

I came across a silverface Deluxe Reverb yesterday and don't know if I'm interested or not. Depends on the date. There's no stamp on the tube chart. I forgot to check for the pull knob on the volume control. It's a non-master with the blue pinstriping on the panel. Replacement speaker and I suspect the bottom back panel is too. It's pretty flimsy.

I seem to recall that there's a way to check the date by the transformer codes. Could somebody refresh my (alleged) memory on how to do this?

Oh, and while I'm thinking about it, what's involved in 'blackfacing' an amp like this?

[bobbymack]

I came across a silverface Deluxe Reverb yesterday and don't know if I'm interested or not. Depends on the date. There's no stamp on the tube chart. I forgot to check for the pull knob on the volume control. It's a non-master with the blue pinstriping on the panel. Replacement speaker and I suspect the bottom back panel is too. It's pretty flimsy.

I seem to recall that there's a way to check the date by the transformer codes. Could somebody refresh my (alleged) memory on how to do this?

Oh, and while I'm thinking about it, what's involved in 'blackfacing' an amp like this?

DATING FENDER TUBE AMPS BY SERIAL NUMBER

http://www.tcguitar.com/articles/gagliano_pt2.html

Blackfacing depends on the date, generally the further from '67 the more involved the mods are...some of the '68s through '70 or so Deluxes were not changed at all, blackfaces in a silverface package...

[Thundernotes]

If you can get the ashtray cover off the bottom of the chassis (4 screws), the capacitors have easy-to-read date codes on them. i.e. "7126" would be the 26th week of 1971. Here's how you date the transformers:

DATING FENDER TRANSFORMERS, SPEAKERS & POTENTIOMETERS USING EIA CODES

EIA (Electronics Industry Association) Source-Date Codes: Electronic components such as transformers, potentiometers, speakers, and some capacitors are often stamped with a date code, which indicates the manufacturer and the manufacturing date.

The code follows the format: XXXYYZZ, where:

XXX = a two or three digit number (possibly four on newer amps) indicating the manufacturer. (refer to the chart shown below)

YY = is a one or two digit code indicating the year of manufacture. If it's a one-digit number you need to determine the correct decade of the amp some other way.

ZZ = a number from 1 - 52 indicating the week of manufacture.

Remember, your amp is newer than the newest component. For example, if you find pots from late '64 and transformers from early '65, you can be pretty sure your amp is a 1965.

Blackfacing isn't an exact science - due to changes in power supply voltages (higher in later years). The voltages can be altered, but then you don't have a "true" blackface circuit any more. Everything affects how the amp responds to a given input. There are a number of resistor and cap changes/removals that can be done to bring the amp closer to blackface specs and more importantly - blackface sound. There's some background info on the changes here: http://acruhl.freeshell.org/mga/main/sf_bf_mod.html

I've heard some silverface amps that sounded great and blackfaces that sounded like crap too. The nice thing is that the circuits are easy to modify and experiment with until you're happy with the sound.

If you want to send me a PM with your phone #, I can give you a call this weekend. (I guess I misplaced it)

[tomteriffic]

Thanks, Brian. I'm going to go look at it a little more closely and see if the owner has any wiggle room on the price first. The ask on it is on the high side from what I can tell. There's sense getting too crazy on it if I'm not going to grab it.