PPAs help - echoey sound

[el_matt0]

hey im just finishing up puTting together my PPAs...few problems however that are making me pretty nervous about whether or not this thing is gunna end up working! firstly, im using AD8066 as my OPALR, and an OPA690 as my OPAG. someone recommended i use the opa690 unbuffered, so nothing in the BUFG position, and using 2 LMH6321 in my BUFL and BUFR spots. it was only AFTER ordering up my parts that AMB told me the 690 isnt a great choice for a buffer, and i should at least add a ferrite bead on its output (which im also a little unsure as how to do). ive got it wired up for testing, and i get sound fine, and its ALMOST clean, but its moderately echoey listening throguh a cheapy pair of headphones. ive checked for solderbridges...de fluxed my board etc, but it still sounds like something is a little bit wrong. would this actually be the lack of a ferrite bead on the opa690? something that MIGHT be the big source of the problem is...when soldering a jumper across the BUFG position, from pin 1 to the one opposite it (i hope that was the right thing to do), the jumper actually "pulled" one of the silver pads on the PCB right clean off. im pretty lost as exactly what i should do next...even while listening through a pair of headphones, whether or not that jumper is connected across BUFG makes NO difference to the sound SO...i know something aint right. lol. once again, im sorry for the noobie questions..im in a bad boat

 

[MisterX]

It never occurred to you to check the buffer's datasheet for what pins are the ins and outs before you decided to jumper it any random way you choose?

I am pretty sure you will figure out the problem after doing so.

 

[Fitz]

Quote:

Originally Posted by MisterX /img/forum/go_quote.gif It never occurred to you to check the buffer's datasheet for what pins are the ins and outs before you decided to jumper it any random way you choose? I am pretty sure you will figure out the problem after doing so.

Nonsense, I always jumper the error flag and not connected pins together. It takes the system to the next level of extreme.

For the OP: Pin 3 is input, pin 6 is output.

 

[MisterX]

Quote:

Originally Posted by Fitz /img/forum/go_quote.gif Nonsense, I always jumper the error flag and not connected pins together. It takes the system to the next level of extreme.

There is quite a lot to be said for the smell of DC offset running through your cans but......