• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

What’s he building in there?

gregd

gregd

Well-Known Member
I recently participated in an online auction estate sale near me.
The auction included probably 500 vintage audio related items, tons of tube gear mostly dynaco, heath kit, Sherwood etc….
It was all untested some in various stages of repair and strewn about several outbuildings open to the elements. The bidding got into territory reserved for functional units, and I’m cheap, so I didn’t get much.
What I did end up with was listed as “incomplete project boxes”.
It appears to be some kind of a preamp?
Clearly not finished, and way beyond my skill set to continue but I know some of you folks are into this sort of thing so I thought I would share.
 

Attachments

  • E5C491D8-81AD-4956-9D0C-7FCC1B10CFEE.jpeg
    E5C491D8-81AD-4956-9D0C-7FCC1B10CFEE.jpeg
    114.8 KB · Views: 112
  • F19A13CE-4AEB-4853-B72F-0953DC44B8DE.jpeg
    F19A13CE-4AEB-4853-B72F-0953DC44B8DE.jpeg
    117.8 KB · Views: 112
  • 03063FCE-7887-4CE8-A599-51507046DCAA.jpeg
    03063FCE-7887-4CE8-A599-51507046DCAA.jpeg
    115.3 KB · Views: 111
Register to hide this ad
Looks like relays for three inputs, connectors for three inputs and an output. I would have used double-pole reed relays myself... half as many. Anyway, if the microprocessor code isn't loaded, it's just a collection of parts that can't function.
 
Tom Bavis said:
Looks like relays for three inputs, connectors for three inputs and an output. I would have used double-pole reed relays myself... half as many. Anyway, if the microprocessor code isn't loaded, it's just a collection of parts that can't function.
Click to expand...
Can we call it "the clicking wonder?"
 
Tom Bavis said:
Looks like relays for three inputs, connectors for three inputs and an output. I would have used double-pole reed relays myself... half as many. Anyway, if the microprocessor code isn't loaded, it's just a collection of parts that can't function.
Click to expand...
Pretty sure it’s just a collection of parts even if the microprocessor code is loaded .
I got 4 of these chassis, two had stuff in them the other two were empty but had face plates on them.
The other one had a remote clunking around inside.
I googled “LCR audio” but didn’t find anything related to what I have.
This guy was in deep!
 

Attachments

  • image.jpg
    image.jpg
    87 KB · Views: 55
  • image.jpg
    image.jpg
    119.8 KB · Views: 55
looks like one of those ebay remote controlled relay input boards. Common and cheap, but not a bad thing. They sometimes also have a motorized volume control, or less ideally a digital volume control.


Boards look like they may be Dyna PAS parts in the one with two circuit boards. Any other markings? PAS boards have PC-5 and PC-6 on the bottom side somewhere

the 3 tube board may also be some Dyna PAS unit but there have been a lot of assorted tube preamp boards sold on ebay and other places. Could be any of them.
 
Neat find. You've got a couple of good preamp chassis. Tubes relays and sockets are highly useful. I hope you didn't pay a whole lot. Tube amps are what their transformers will do. Your preamps don't appear to include power supply transformers, nor input/output transformers.
 
gadget73 said:
looks like one of those ebay remote controlled relay input boards. Common and cheap, but not a bad thing. They sometimes also have a motorized volume control, or less ideally a digital volume control.


Boards look like they may be Dyna PAS parts in the one with two circuit boards. Any other markings? PAS boards have PC-5 and PC-6 on the bottom side somewhere

the 3 tube board may also be some Dyna PAS unit but there have been a lot of assorted tube preamp boards sold on ebay and other places. Could be any of them.
Click to expand...
This guy had a ton of Dyna pas stuff in various stages of repair so that would make sense.
 
trainbuftony said:
Neat find. You've got a couple of good preamp chassis. Tubes relays and sockets are highly useful. I hope you didn't pay a whole lot. Tube amps are what their transformers will do. Your preamps don't appear to include power supply transformers, nor input/output transformers.
Click to expand...
Basically free.
The guy had a ton of transformers, all kinds pulled form the source as well as NIB Edcores, Triads, and some toroidal things that I looked up online and found them to be quite pricey. Bidding went far beyond my range.
 
Those cheap input relay boards work fine. They dont make much if any noise when activated. I've used a couple over the years.
pictures of the boards with tubes could help to identify them. Its hard to tell looking at them from the sides. The three tube board may be one of those Chinese "clone" Marantz 7 line stage boards?
 
You got yourself some nearly free Telefunken 12ax7s.
That's the right price on those.
Unfortunately without some sort of power supply, these aren't going to do much from an electrical standpoint.
They'll make a fine paper weight though...
 
Lavane said:
Those cheap input relay boards work fine. They dont make much if any noise when activated. I've used a couple over the years.
pictures of the boards with tubes could help to identify them. Its hard to tell looking at them from the sides. The three tube board may be one of those Chinese "clone" Marantz 7 line stage boards?
Click to expand...
 

Attachments

  • image.jpg
    image.jpg
    122.5 KB · Views: 34
  • image.jpg
    image.jpg
    154.7 KB · Views: 34
  • image.jpg
    image.jpg
    111.6 KB · Views: 34
well if they are indeed Dyna bits, power supply is easy. Clone a Dynaco one. One nice thing here, you don't have to reverse-engineer anything. No wiring exists, its just some parts in a box. You can hook them up any way you desire.

or just keep the tubes and dump the other bits for what you paid for it. Free tubes and someone gets a project.
 
Lavane said:
Those cheap input relay boards work fine. They dont make much if any noise when activated. I've used a couple over the years.
pictures of the boards with tubes could help to identify them. Its hard to tell looking at them from the sides. The three tube board may be one of those Chinese "clone" Marantz 7 line stage boards?
Click to expand...
I just googled “Marantz 7 clone”, didn’t realize such things existed. I thought it might be a way to spec a power transformer, but the one I looked at didn’t seem to include one. More googling in my future.
 
gregd said:
I just googled “Marantz 7 clone”, didn’t realize such things existed. I thought it might be a way to spec a power transformer, but the one I looked at didn’t seem to include one. More googling in my future.
Click to expand...
Only a couple I think are acually clones of the Marantz 7 line stage. Most of them are "based" on the 7. Whatever that really means.
 
would be interesting to trace one out and see how close it even is. The 7 has tone controls, none of these do. One quirk of the 7's design though is that the tone controls were switchable RC pairs rather than the usual adjustable pot. In theory you could use the RC values for "flat" and hard-wire that into the circuit but I have my doubts that they did that.

If they did though, it also means you could pop those parts out and wire in the switch like an actual Marantz 7 has and populate it with the parts to get a full set of tone controls.
 
I really dought most 7 clones are really that close to the original other than using 3 12AX7 tubes. There are a couple xomplete finished preamps that are supposed to be close though. And no they don't have tone controls. But they also cost a lot more than the cheap versions and board kits. That board may sound ok though If you sort out what wires where. You would have to make a drawing tracing out the circuit on the PCB following the traces. Not fun though.
 
You must log in or register to reply here.
Back
Top Bottom