What We've All Been Waiting For--700 BP boards!!!!!!!!!

[Gepetto]

OK, LOL... I'm thinkin Nav's hold downs will do the trick to keeping the solder on the bottom side we'll see.

You will naturally get some reflow of the HASL on the topside regardless Lee, that is to be expected and tells you that you do not have a cold solder joint.

 

[laatsch55]

OI can see you did a helluva job to get everything on there and still keep distance where needed..

 

[laatsch55]

You will naturally get some reflow of the HASL on the topside regardless Lee, that is to be expected and tells you that you do not have a cold solder joint.

I understand, I want it to be on my terms though, nice and neat and not balled up. somehow....

 

[laatsch55]

A D500 transformer is the same size and mounts the same as a 700 transformer..

 

[Michael F]

Only Full Complementary. No quasi option, not enough room.

Compatible with Rev C board?

 

[laatsch55]

Not without a lot of cobbling.

 

[Gepetto]

Some eye candy for you conversion enthusiasts...

 

[laatsch55]

Pretty damn nice Joe!

 

[Gibsonian]

Meticulous looking Joe.

 

[laatsch55]

Joe, still tying input to ground with 220K?

 

[Gepetto]

Joe, still tying input to ground with 220K?

Yes Lee, it is a non critical resistor value. It's purpose is to keep charge buildup off the coupling caps (now 1uF in this build) so that you don't get popping when interconnect cables are installed. Once cables are installed, it is a do nothing resistor.

 

[laatsch55]

Has nothing to do with input impedence? Is that the normal/direct coupling switch? And if so , with response flat to 10 hz now why are we even messing with that?

 

[laatsch55]

I love the OCD ground plane!!

 

[Gepetto]

Has nothing to do with input impedence? Is that the normal/direct coupling switch? And if so , with response flat to 10 hz now why are we even messing with that?

Slight extra input impedance loading Lee It changes the nominal 49K input impedance (at low frequencies) to 41K.

It is the NORMAL/DIRECT switch cap that I am referring to in the note. With a 1uF cap installed in that location, the cutoff frequency is 3Hz so does not affect the low end even when operated in NORMAL mode.

I am doing this to keep the functional behavior of this amp intact (while at the same time improving its performance).

 

[Gepetto]

I love the OCD ground plane!!

???

 

[laatsch55]

So we are keeping that switch for a 3hz difference?

 

[laatsch55]

???

On the speaker negative posts. VERY nice fab job on that piece of copper Joe.

 

[Gepetto]

So we are keeping that switch for a 3hz difference?

No Lee
Keeping it for my ability to test the amp in both modes and be able to provide results. I usually run direct mode.

 

[Gepetto]

On the speaker negative posts. VERY nice fab job on that piece of copper Joe.

Don't you just love the original twisted mess of wires that PL installed? The little things that they did not do that they should have done. That and the one pound pool of solder on most copper input plates when a couple of 0.043" holes punched in that plate would have made all the difference.

They did not do anything over the years of production to re-engineer for ease of manufacturability and higher quality.

 

[laatsch55]

To stay consistent and be able to compare results I should rig this one as you are rigging yours then?