Fun on Dave's bench!

premiumplus

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#1
Hey guys,
I got my SAE 2100L preamp yesterday and spent some time recapping it and getting a bad hum out of it.
Those old SAE's are sure purty but they're a bitch to work on. I'm glad I wasn't working on someone elses...I think it would be hard to make money on one of these!
Here's some pictures...I'm really enjoying it. Sounds Great!

DSC_5634_3790.jpg DSC_5635_3791.jpg DSC_5636_3792.jpg DSC_5637_3793.jpg DSC_5638_3794.jpg
 
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#2
Dave: You were quickly at it, weren't you? I'm sorry to say, I haven't got mine patched into a system, yet. That bodes well for my own if you like what you've heard, so far. Judging by your pictures the circuit boards look modular. The recap took a great amount of time because of the disassembly?

Nando.
 

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#5
Thank you, gentlemen...I love my electronics! My bench is a perpetual mess, though. Don't know about you, but I am lazy when it comes to tidying up. It's been said that a clean bench is the sign of a sick mind...
Nando: Yes, it's a pita to work on with all the ribbon cables and interconnects. There are 6 boards in there and you better have an electric screwdriver when it comes time to open it up...dozens of screws. But they're beautifully made.
I thought I was all done, but now my Aux 2 inputs are flaky. I'll open it up again in a day or two.
It sure sounds great though. Thanks for the tip, Nando!
 

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#6
Dummy load...

You'll get a kick out of what I'm using for a dummy load...my wife's 2Kw ceramic kiln!
I used this the other day when I put new output transistors into my new 700B. It got quite warm in there during load sharing tests. :confused2:
DSC_5632_3788.jpg DSC_5633_3789.jpg
 

Elite-ist

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Quite resourceful of you, Dave. I know Lee might have bragged about going one step further and toasting a BLT sandwich in the kiln.

Nando.
 

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#8
Have you tried running the phono section, yet? That can make or break a possible candidate for a suitable preamplifier.

Nando.
 

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Or at least warmed up the coffee. Dave, what's the resistance ad did you leave the meter on it to check for differing resistance as it warmed up??
 

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Nice photos! I see high-quality parts (What brand are those gorgeous pots?) and microchips everywhere. It's a preamp, right? Then what are those things in the back that look like speaker binding posts? Long ago I had a non-working (later gave it away) Marantz preamp with the same thing, and it puzzled me then too.
 

BubbaH

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From Nando's pics, I thought the unit was an integrated. Never seen one in the flesh though so, I dont know.
 

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Laz, those pots are Alps. They still make em. The one for the Spec 1 is a 4 gang and lists for 436.00 Ya see a lot of 2 gang and they can be had fairly cheap. The Chinese are into counterfeiting these bigf time so be careful on e-bay.,
 

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Nice photos! I see high-quality parts (What brand are those gorgeous pots?) and microchips everywhere. It's a preamp, right? Then what are those things in the back that look like speaker binding posts? Long ago I had a non-working (later gave it away) Marantz preamp with the same thing, and it puzzled me then too.

Laz with some preamps that have speaker switching capability bring the output from the amp; back to the preamp to switch.
 

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#16
Or at least warmed up the coffee. Dave, what's the resistance ad did you leave the meter on it to check for differing resistance as it warmed up??
Lee, I measured it right after disconnection, and it read around 9.5 ohms. A very happy coincidence. And I haven't measured it's inductance, but I was careful to make sure the amp didn't decide to oscillate. I ran it at 200 Hz, and didn't encounter any problems. Different frequencies may create problems though...I don't have any evidence that oscillation will occur, but it's always good to look out for it with anything inductive.
 

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Yes it is Dave. Oscillations aren't usually in the audible range though. Throw some 20K at it....
 

orange

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#19
Don't have too much fun on that bench, Dave...ladies like piercings but not an Elna 68000uF cap stuck somewhere the sun doesn't normally find...
 

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#20
I seee we're going to have to have a "Member's Test Equipment Album" yes???
 
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