Zenith tube console

jera

AK Subscriber
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okay so I found another tube console today .It is a zenith with phono only .I have not decided whether I should get it or not .My last console find is still sitting on my desk .It turned out that it will be more work than I'm able to do . This one on the other hand is working. so my question is would this be worth getting to use as a stand-alone amp. since it only has phono. Would this be a Large conversion project ? I don't know the exact model but it has 2. El84, 12au7 and 1, 7025 .also it is stereo and my electrical bqck ground is zero.
 
If you are talking about making it a stand-alone amp outside of the console, there will undoubtedly by some reworking of the circuit - adding a power switch, fuse, and usually removing connectors to other components in the cabinet.
Also, you will need to replace the electrolytic capacitors at a minimum - these are found in the power section of the amp. So, soldering skills are necessary, as well as a desire to learn how to read a schematic and be able to identify components and understand what they do.
That is how I learned - got a Magnavox console amp and turned it into a stand alone amp. It is doable if you have the desire to learn about simple circuits.
 
okay so I found another tube console today .It is a zenith with phono only .I have not decided whether I should get it or not .My last console find is still sitting on my desk .It turned out that it will be more work than I'm able to do . This one on the other hand is working. so my question is would this be worth getting to use as a stand-alone amp. since it only has phono. Would this be a Large conversion project ? I don't know the exact model but it has 2. El84, 12au7 and 1, 7025 .also it is stereo and my electrical bqck ground is zero.

I picked up a Zenith tube console with phono only but being a mono unit would need another. It's tube amp seems in excellent condition but haven't decided what to do with it. I bought it mainly for the large alnico full range speakers.
 
The phono only isn't usually a problem. Those consoles almost always used a ceramic cartridge, which is line-level input. To connect it to some other source, you just need to unplug the phono and feed something else in. The power switch is typically built into the turntable though, so you usually need to do a little wiring work to add a switch in. Nothing major. Plus it will need the caps as mentioned.
 
My Zenith chassis 5Z21 is a 6V6. Another like it would make for a nice pair of mono blocks.

This is one minty amp from the the 1950's and shows little signs of use. I checked the tubes and all test strong. It has the Cobra-matic TT ( line level? ).

I'm not sure what to do with it. Too many projects and so little time. :sigh:
 
The earlier Zenith cobramatics used a weird cartridge that used an oscillator and coil to pick up AM modulated sound from the needle, these are not realy a line input at all. Zenith switched to fairly normal ceramic cartridges by about 1953 or 1954 I think.
 
I found a schematic online, looks like your 5z21 is a normal ceramic cartridge input, with the added benefit of adjustable EQ curves. A lot of companies added filter circuits to the ceramic phono inputs to improve the frequency response - or in this case to accomodate the plethora of EQ curves used in the 1950s , these depend on the particular cartridge they were using, for use as a regular line input you may need to bypass that.
 
Very old thread but to update I sold the 6v6 amp and the Cobramatic but kept the 12" alnico speakers. These full rangers turned out to be an incredible find. Amazing in simple open baffles. The "Glow in the Dark Audio" blog gives more information on these Zenith speakers.
 
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