Did I get Switcherood?

[jeskibuff]

Have any of you ever heard of part swapping when you or anyone else has taken a unit to be serviced??

I doubt that this happened. It'd be more trouble than it's worth just for some transistors. An easy way to find out is to see what the part number for the transistors should be. The number should be printed right on the face of each transistor. If that differs from what Sony says should be in place, then yes, you have an issue. A phone call to an authorized service center should get you the "real" part number.

[ciscokid1970]

Well hello again...

I went home hooked up the receiver and it definatly does not sound the same. It is brighter and missing some richness in the bass.

Took the lid off the unit and sure enough I can see the old footprint of where the old transistors were and they were bigger the new ones are smaller and I can see fresh solder on the board.

I am getting a little ticked off.

I wrote down the numbers and am calling SONY corporate service center ASAP.

I think I will take digital pics and mail them.

see ya guys

[kingdaddykeith]

The white goop is heat sink compound and should be there, it helps the transistors to make better thermo contact with the heat sink, you probably just didn't notice it before. Sometimes you get you fingers into some of this when your working around the heat sink and then you end up smearing it all over the place.

[Mash]

There are two apparent outcomes here

1. The power transistors WERE switched, and the unit may then have a valid reason to sound 'different' to ciscokid1970. Then no new light will be shed on "sighted" perceived differences.
.
a. Someone pulled a 'rip-off' on ciscokid1970 and stole his transistors.......
b. There is/was a silent recall from Sony, perhaps because of safety, and so the power transistors were changed without telling/asking ciscokid1970. Not a best practice.

2. The power transistors WERE NOT switched, and the unit should then have no apparent reason to sound 'different'. ciscokid1970's perceived difference would, of course, seem to be a "sighted" perceived difference as ciscokid1970 believed something WAS changed and now he perceives an audible difference.

Gosh, this is exciting. The Audiopile Cable & Interconnects World awaits the results of ciscokid1970's query to Sony........

[pelly3s]

I work in a pro audio shop as a service tech and i always touch up solder joints on things like transistors or multipin connectors whenever i am inside of an amp. it's just good practice, i also apply thremal compound where needed. that is something every tech should do just as good practice. the fact they look smaller is something i can't explain, just ask the repair shop and see what they say. i always include a bag full of parts i replace when working on a piece of gear just so the customer can see exactly what was changed. check the part numbers that is the best thing you can do, but i have never heard of anyone changing out parts only to take them. it's too much effort and time. there may have been an issue with one of the transistors and as you should do with any amp you change them all when one goes bad.

[ciscokid1970]

Ok here goes.

After the sound test...which was different. I called sony...which was barely helpful...they at first told me to call a 900 number (which is blocked at work, blocked on my personal mobile and did not try at home.

Finally I called sony again and they told me to take it to another service center, So I did.

Took it in and spoke to the tech told him my story, as he opened up the top.

He noticed what I noticed, white goop all over the place and smaller transistors on the heat sink. He looked up the numbers and sure enough they were the transistors for the DB series (which is between the ES and the el cheapo sonys).

The tech offered two scenarios:
1. Swapped my parts out for cheaper parts to fix a out of warranty unit or stock himself up (although the tech thought this is highly unlikely).
2. the original tech damaged one of the transistors when he moved the board to get to the servo motor that needed to be replaced. Did not tell me and did not want to wait for the ES parts to be delivered so he used what he had that almost fits. (This is most likely scenario.

Anyway the new tech will replace all the transistors with REAL ES transistors and replace the board that may have been shorted. It will take another week before the parts are in. Aparently these parts (transistors and board) are worth over $300

After I get it repaired I will write a letter to the first shop...and ask them what really happened.

So moral of the story...before you take your unit in...whatever it is...take some digital pics of the inside to compare before and after.