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Ampex 6v6 PP.. worth saving?

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Ive got a couple of old ampex speaker amps that I have turned into a pair of mono blocks. I never use them.. So, my next project is a phono amp and line stage. It just happens to work out the ampex amps have the power transformers and rectifiers, and exact number of tube sockets I need. If I do use these chassis, I'd take the output tx off, and put the choke there or something...

So.. Is this ampex worth anything to collectors or anything? I don't want to destroy something w/ some antique value to it. So.. I'll either build the line stage into these chassis, or sell these ampex and start purchasing parts for the new project.

Here's a photo.. they aren't quite stock as I painted the old chassis and built this wood box around them. Under the hood they are almost stock.. some slight circuit mods, and replaced the caps.
 

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As a long time Ampex fan I'll offer you my opinion. Ampex is much better known for their tape machines then their amplifiers. The exception to this is their old 350-351 series recorder electronics. These seem to have become a cult item that people are willing to pay stupid money for as microphone preamps. Your amps are nice but the "antique" value has been compromised somewhat by the paint job and circuit mods for a true collector. While they still have resale value, so do the output trannys. Unless you find someone that just has to have them, I say go ahead and reuse them and sell the outputs.
 
They're either the 612 or 620's.. (basically the same thing) I attached a schematic. I removed the tone/compensation network (bottom left stuff on this schematic) and triode wired the power tubes.. maybe the input tube too. I might have even put them back to pentode before I put them away. I don't remember. Its been a few years since I looked at them.

The 2 replies Ive gotten are like the two sides of my brain each made a post, and I'm right where I started :D
 

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diyAudio Chief Moderator
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Those look like the Miniwatt that I was describing in the next door 6V6 thread.
They must be exactly the same. Amperex was a Philips factory, arguably its best quality production unit. Amperex logo fetches much more $ in the NOS collector market in general than the same tubes if marked Philips. That has not to do with audio sanity, its almost an art boutique vintage market.:yuck: You scratch the logo or write something on the box, you lose half $:cuss:
 
The other parts of the story are that the power TX isn't actually ideal, as its about 50 volts too many, so thats a point for selling.
OTOH, I can dig in and get my hands dirty w/ parts I've got on hand if I use this chassis, while if I start from scratch I'll probably be tempted by an aikido pcb or something less challanging/more expensive.. so there's a point for keeping.

Owell, I guess I'll have to go about this more logically, and add up costs for new parts, etc..

One last question, and I know this will just have to be a random guess. Any idea what a pair of 6v6 pp monoblocks would sell for?
 
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