Silvertone amp(s)-in-case(s)

[dkevin]

Hello all,
I have two of these fine amps and I am wondering how to get my hands on the schematics. Are they listed on Schematic Heaven under 1449 (for the 12AU6-50C5-35W4 version and 1457 for the 12AX7-12AX7-6V6-6X4 versions? I have the guitar with the smaller amp but only the amp-in-case for the larger amp.
Thanks for your help!
dkevin

[Patrick620]

Try here http://www.prowessamplifiers.com/schematics/silvertone/

or here http://www.freeinfosociety.com/electronics/schempage.php?cat=1

or here http://www.silvertoneworld.com/amps.html

google is a great thing ;)

[drbob1]

Do be careful! The smaller version is the type of amp that doesn't have a power transformer, meaning that one side of the AC is directly attached to the amp chassis. Create a circuit by standing on a damp floor, kissing a mic or touching a pipe and you may find yourself doing a credible imitation of a power resistor. They're safe if they're plugged into a transformer based power supply, or if you use a transformer coupled input inline (like the Ebtech Hum Eliminator or the second out of an AmpBone), or it you rebuild with a power transformer.

[Patrick620]

Do be careful! The smaller version is the type of amp that doesn't have a power transformer, meaning that one side of the AC is directly attached to the amp chassis. Create a circuit by standing on a damp floor, kissing a mic or touching a pipe and you may find yourself doing a credible imitation of a power resistor. They're safe if they're plugged into a transformer based power supply, or if you use a transformer coupled input inline (like the Ebtech Hum Eliminator or the second out of an AmpBone), or it you rebuild with a power transformer.
I was not aware of that or I would have offered the same warning. Ya, those "shocker" amps are dangerous. Thick rubber soled shoes are a great idea with those amps. When I was a kid, I shocked the crap out of myself with one of those by playing in the garage (dry concrete floor) while barefoot. Any amp that uses tubes that begin with a number higher than "12" should be considered suspect.

[devnulljp]

I have one of these. Got a nasty belt off it, and it will never get plugged in again. The death cap has been replaced, but still I don't trust it.
Tell me about this external isolation transformer thing though...

[stratman_el84]

I have one of these. Got a nasty belt off it, and it will never get plugged in again. The death cap has been replaced, but still I don't trust it.
Tell me about this external isolation transformer thing though...


Unfortunately, isolation transformers are expensive. Even one that handles only ~1.6 amps (200VA...the "VA" is for "Volt/Amps", and effectively means the same as "Watts", so 200VA or 200watts divided by 125 volts = 1.6 amps) will cost around ~$100 or so. Check the amp's rear panel for the power requirements, or check what size AC power/mains fuse is called for and do the math.

http://www.mouser.com/ProductDetail/Hammond/171B/?qs=jcD%2fCkGBYeN5kvlA5nBPlw%3d%3d

You could also buy one of the more deluxe AC power filter and isolation rack units, but I'd think the cost would only be worth it if you had other equipment to plug into it.


Strat

[Don A]

Here's a pretty good set of instructions for installing an isolation transformer. It's not expensive at all.

http://www.instructables.com/id/Isolation-transformer-upgrade-for-old-guitar-amps/

[dkevin]

While I appreciate all the input about the dangers of transformerless amps and the need for isolation transformers, this was not the main focus of my question.
I was seeking clarification for the model numbers of the amp-in-case amplifiers only. I suspect that they were given a model number when paired with a guitar (single-pickup/ double pickup) and referred to with a different model number when the amp was by itself.
Can anyone shed some light on the mind of Silvertone when it came specifically to the amp(s)-in case(s)?
Thanks again!

[devnulljp]

While I appreciate all the input about the dangers of transformerless amps and the need for isolation transformers, this was not the main focus of my question.
I was seeking clarification for the model numbers of the amp-in-case amplifiers only. I suspect that they were given a model number when paired with a guitar (single-pickup/ double pickup) and referred to with a different model number when the amp was by itself.
Can anyone shed some light on the mind of Silvertone when it came specifically to the amp(s)-in case(s)?
Thanks again!Mine is a 1448 -- short scale, single pickup.

http://i440.photobucket.com/albums/qq123/devnulljp/Silvertone/c9c80704.jpg
http://i440.photobucket.com/albums/qq123/devnulljp/Silvertone/d59b3775.jpg
http://i440.photobucket.com/albums/qq123/devnulljp/Silvertone/3086d9ae.jpg
http://i440.photobucket.com/albums/qq123/devnulljp/Silvertone/a5171044.jpg
http://i440.photobucket.com/albums/qq123/devnulljp/Silvertone/4fdc8502.jpg
http://i440.photobucket.com/albums/qq123/devnulljp/Silvertone/8720c007.jpg

[dkevin]

I have been looking at the Silvertone World site and the Wikipedia site and I think I understand some of the details. In 1962 the 1448 was first sold. That amp had 3 watts, 3 tubes, no power transformer (eek!) and a 5 inch speaker.The only control was a volume (gain) knob.
In 1963 Silvertone offered a 1449 that had 5 watts, 4 tubes, a surface mounted power transformer and an 8 inch speaker. It had a volume pot, trem speed, trem strength and tone controls. There was a footswitch for the trem.
In 1964 the 1449 changed into a 1457. The amp remained the same but the guitar was altered.
In 1966 both of the amp-in-case models were changed due to a redesign of the guitars offered. The 1448 became a 1451 and the 1457 became a 1452. Other design details seem to have remained the same. These later versions have the speaker mounted on the lid side of the case (as opposed to the amp side of the case).
Schematic Heaven has the schematics listed as "1448", "1449" and "1457"
There are only the two amps available. The transformer-less version features a 12AU6-50C5 and 35W4. The tremelo version has a 12AX7-12AX7-6V6-6X4 tube lineup.
Whew!

[Patrick620]

If you are as old as I am, you'd better think about it. High voltage in one arm and out the other is no joke. ALWAYS SAFETY FIRST!!!!!!!!