TI chip question

[fender3x]

I just got the TI chip that some folks have used to replace the IC on their pres.... and I have a really boneheaded question. How do I orient it? There's a "dot" (slight round indentation) in one corner on both chips. Is that how I orient it? Put the dots in the same corner? Or is there some other way?

Obviously, an electronic genius, I ain't ;-)

[spideyjg]

The rule of ICs is to put the dot by "pin 1".

Match them and you will be fine.

Jim

[Ken Baker]

Originally Posted by fender3x

I just got the TI chip that some folks have used to replace the IC on their pres.... and I have a really boneheaded question. How do I orient it? There's a "dot" (slight round indentation) in one corner on both chips. Is that how I orient it? Put the dots in the same corner? Or is there some other way?

Obviously, an electronic genius, I ain't ;-)

Not a boneheaded question at all. If you don't know, how you gonna learn?

As Jim said, a dot or indentation corresponds to pin 1. Call it an industry standard.

Here's an image of a G&L preamp. The IC's pin 1 indent/dot is clearly visible.


http://www.bassesbyleo.com/images/l-...amp/pretop.jpg

IC sockets usually have a notch at one end that corresponds to the pin one end of the IC. A notch like this is common, but pin 1 can be identified in pretty much any clear manner. In this particular socket, the "2" is meaningless as to pin orientation.


http://www.effectsconnection.com/osc...socket%201.jpg

All you have to do is line 'em up. In the G&L preamp image above you can't see the socket's pin 1 notch, but it is under the pin 1 end of the IC.

These are usually things that you can count on unless a circuit board is manually stuffed by a sloppy assembler.

Ken...

[fender3x]

Thanks, guys!

Originally Posted by Ken Baker

The pic was a great help. Astounding how similar my 1.0 pre is to the 1.1 in the pic. I don't know if all the values are the same, but the placement of resisters, caps and the IC are identical. I had heard they were similar, but now I wonder if there is actually any difference?

Thanks again!

[Ken Baker]

Originally Posted by fender3x

...I had heard they were similar, but now I wonder if there is actually any difference?

They're very close to the same. I'm told that the voicing is just a tad different.

Ken...

[vicenzajay]

I know I could search and probably find this info, but I'm lazy and this thread seems perfect for the question:

- What does this chip do (or, better, what is the impetus for this mod)? I like my L2000's sound, but I've missed this discussion somehow over the past four years.

- What's the "identification" of the chip (i.e. what it's "number"; how do you get them)?

At the end of the day, I probably won't do anything to my L2000's preamp; however, I figure it can't hurt to get the information.

By the way, great pictures, Ken!

Jay

[Ken Baker]

Originally Posted by vicenzajay

- What does this chip do (or, better, what is the impetus for this mod)? I like my L2000's sound, but I've missed 't this discussion somehow over the past four years.

I can't come up with a really good, "You can hear it" reason. Daveplaysbass has compared specs between the factory chip and the TI replacement and the TI has better slew rate numbers.

- What's the "identification" of the chip (i.e. what it's "number"; how do you get them)?

http://www.bassesbyleo.com/images/mi...tedbastard.jpg

They're OEM modules that aren't generally available through retail outlets. Sourcing them might be tough these days, as I understand that TI has clamped down on samples.

By the way, great pictures, Ken!

Thanks! If you saw the old camera I use for macro stuff, you'd probably just shake your head.

Ken...

[fender3x]

Originally Posted by Ken Baker

I can't come up with a really good, "You can hear it" reason. Daveplaysbass has compared specs between the factory chip and the TI replacement and the TI has better slew rate numbers.

Spidey also says that it draws a tad less power so may have better battery life. I suspect that the advantages will be minimal, but the price was right. I got a free sample from TI, and it was easily replaceable on my pre...

[Ken Baker]

Originally Posted by fender3x

I suspect that the advantages will be minimal, but the price was right.

I'd agree with that, certainly as implemented here.

Now, add in some support components and another chip for active EQ and you might have a compelling difference.

But I'm dreamin'.

Ken...