Burson Dual opamp HELP

I just got a pair of Burson Dual discrete opamp and installed it on my Philips cd620.
But I do not know how to ground the op amp.
It is suggested that I can ground it to a RCA connector, but there is obvious noise with I ground it to the RCA(-ve side).
Please give me some help.
Thank you.
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
Why do they need a separate ground. They can't be a "direct replacement" if extra connections required. I would suggest you earth it to a signal ground close to the op-amp. See if pins 2 or 3 connect either directly to ground or if they connect via a single resistor to ground. If you are not sure you need a meter to measue ohms to locate. Was there no documentation supplied ?
Regards Karl
 
Should be no noise!

They can surely be a direct replacement. However Burson recommend to ground them, for better performance. I have done this, and there are no any problems with the grounding. Just locate a signal ground near the OpAmps. Use a meter if needed (as advised above). Should be no noise!.
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
O.K. First you need to be happy using a meter on LOW ohms range i.e. can you reliably measure down to 1 ohm. Make sure the power to player is off. The outer part of the phono sockets on rear panel is a signal ground (there may be others). You say you connected to this point and the result was poor. Double check this again, and make sure connection is to this "outer" part of socket. Solder the wire to this ground on the P.C.B. at the socket and use meter to check that this point is ZERO ohms as measured from the outer part of socket to the wire. I still find it unbelievable that precise fitting instructions are not provided. If you are sure this is no good and you have noise then I wonder if the "ground wire" should even be connected to a signal ground at all. Without having one of these modules to examine it's impossible to say. It may be that this is a P.S.U. ground. Philips players often have many separate grounds to isolate various parts of the circuit and it is important to use the correct one. I would suggest you contact Burson and ask if this is a signal or P.S.U. ground wire.
Regards Karl
 
Grounding the Bursons OpAmps

indeed not a great picture :eek: but should give an idea.. ;)
 

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finally , I go time to work back on my machine
I have cut out some plastic frame from the CD player and remove the extension of the Burson amp
the noise problem has been improved, but I still get terrible noise if I earth the amp.

I feel so sad .....:(
as sad as Bear Stearn
 
Hi chofaichan,

Since previous monolithic dual opamp serve as current to voltage converter and analog filter, the nearest signal ground is where noninverting input (+IN) is connected, be it from opamp no.1 (or A) or opamp no.2 (or B). So, check with the DVM pins no. 3 and 5, one of them is in direct contact with signal ground, so use that pin to connect separate ground from Burson discrete opamps.

BTW, where you have connected separate ground wire to Burson opamps?