Estey T 12 Amplifier

[jcflea]

I just rescued an Estey T 12 Amplifier from some guys trash. It has a nice crunchy sound when the volume is maxed and a pretty good clean tremelo. Its a small amp that doesn't get very loud but I kinda like the tone. It needs a ground to take out the buzzing and some more cleanup and it should be in good shape.

I don't know anything about vintage amps and I can find very little on the Estey or Magnatone company (I believe Estey bought Magnatone). Did I find a treasure in the trash or are these pretty common?

Here are some pictures:
Front:

Schematic Diagram Inside:

Tubes and Electronics:


I recorded a quick sample of the loud tone and a couple chords with the tremolo for a friend of mine if anyone is interested in how it sounds. Here it is: http://www.zshare.net/audio/4015859a2befb5/

[sportster4eva]

Be careful of that little amp. If it's plugged in the wrong way, the chassis will be live! Even if it's plugged in correctly and the outlet is mis wired, the chassis is live! If you plan on keeping it you might want to consider at least a polarized grounding cord, and really should use an isolation transformer if you plan on using it. I wonder how many people have been shocked by these old line powered beasts.

[52 Bill]

It is a line operated amp, but it does have a isolation transformer at the input stage. Just make sure that the input chassis ground and the line operated grounds never meet!

FWIW, In general Esteys were never that popular. They didn't seem to have very wide distribution.

[jcflea]

Thanks for the tips guys. I'm not very experience with electronics so I'll see if I can find some assistance around here when I get around to replacing the power cord with a grounded cord.

[sportster4eva]

It is a line operated amp, but it does have a isolation transformer at the input stage. Just make sure that the input chassis ground and the line operated grounds never meet!

FWIW, In general Esteys were never that popular. They didn't seem to have very wide distribution.

My Bad..
I should have looked closer at the schem, I didn't zoom in enough to see that the "chassis ground" and the "common return" were sepatated by the 220k and .047 cap. Be careful anyway. That .047 cap should probably be replaced, or at least checked.

[dustyoldamp]

i'm getting ready to buy one of these but the volume is really low, lower than any amp i've played through before and i've got some that are only 1 or 2 watts rms.

the tone of this particular estery t-12 is a beautiful clean, even all the way up, but doesn't get the overdriven tone as described in this thread.

given the supplied schematic earlier in original post, it looks like it should put out 5 watts but the one i played though was putting out only a fraction of that??

anyone have any ideas of what could be causing this? i would appreciate a heads up of what i could be in for once i buy it and start to repair.

thanks in advance!

[52 Bill]

anyone have any ideas of what could be causing this? i would appreciate a heads up of what i could be in for once i buy it and start to repair.

thanks in advance!

It could be a bad tube, bad coupling caps, an off value resistor, a bad speaker, a bad connection...

[pila]

Don't forget about the fun you will have getting it to work good

[dustyoldamp]

It could be a bad tube, bad coupling caps, an off value resistor, a bad speaker, a bad connection...

cheers bill, i just bought it today and will go through it from start to finish as best as i can to try and see what needs to be replaced.

at home in a much quieter environment than the music store it came from, it's somewhat louder than i had realized before, with a wee bit of breakup on slammed chords.

likewise, the clean tone of this thing is to die for...more complex than i could hear in the store, all glorious and shimmery.

looks to have been made in 1967, jensen "special design" 6 inch speaker and three tubes: 20ez7 preamp, 45b5 power, 36am3a rectifier.

[Jerry]

I worked on a 2-el84 Estey about a year and a half ago. It had a 15" Jensen in it. It was quite the screamer when cranked!

[tubessence]

It's in remarkable shape for a dumpster dive, good save! jb