Should I buy that sansui 9090db? your help please

[renzostudent]

Hello everyone, I am very much in love with the sansui 9090db. I have the opportunity to buy it, the seller said that everything is original, and I believed it, but looking for Facebook, I found that it was repaired. I have pictures of what I did and I think it's the Dolby card. The seller is not sincere, and he offers it at USD500.

But does this repair significantly affect the sound? Why can I see this badly repaired? Please, your opinions, I'm about to buy it.

thank you very much

 

[LBPete]

Hard to tell what was repaired from those photos. Were those resistors added? Did he replace the Dolby ICs? Do you have the opportunity to listen to it before purchase? If so, let your ears be the guide.

- Pete

 

[Tom B]

The way prices are going with 9090db's $500usd is a good price for anything.
If it is working, and you can hear sound on both channels, I would jump on it.

Now as far as the repair.
Not sure the reason for the removed IC's on the Dolby board, but I haven't run across them as failure items, but that board can have big issues, especially seeing that it was worked on. There is ribbon cable connecting this board to the switch board above. If it is a grey colored ribbon cable it should be ok. If it is a mylar flat cable that connects to mounting pads on both ends, it can easily be damaged when attempting work on that board. The dolby board itself has "Feed through" connections that may require "pinning" to insure a good connection. The pictures of the board reflect that this hasn't been done. Symptoms of bad feed through connections on the dolby card are intermittant sound on one or both channels, noticable when you flext the board a little. The rotary switch gets very dirty and cause the same problem. This needs to be cleaned and "Deox;d" well.

But the 9090db is a great unit. Spend the $$ to get it, expect to spend some more $$ to have the dolby board repaired, but you will wind up with one of Sansui's best vintage units.

 

[Hipocrates]

Plus it is a good practice to service the driver board.
$500 is a good price, but yo need to know that usually vintage units are not just plug and play, they are at least 40yr old. So save some cash for proper reconditioning as advised.
And talk your concerns with the seller.

 

[renzostudent]

The way prices are going with 9090db's $500usd is a good price for anything.
If it is working, and you can hear sound on both channels, I would jump on it.

Now as far as the repair.
Not sure the reason for the removed IC's on the Dolby board, but I haven't run across them as failure items, but that board can have big issues, especially seeing that it was worked on. There is ribbon cable connecting this board to the switch board above. If it is a grey colored ribbon cable it should be ok. If it is a mylar flat cable that connects to mounting pads on both ends, it can easily be damaged when attempting work on that board. The dolby board itself has "Feed through" connections that may require "pinning" to insure a good connection. The pictures of the board reflect that this hasn't been done. Symptoms of bad feed through connections on the dolby card are intermittant sound on one or both channels, noticable when you flext the board a little. The rotary switch gets very dirty and cause the same problem. This needs to be cleaned and "Deox;d" well.

But the 9090db is a great unit. Spend the $$ to get it, expect to spend some more $$ to have the dolby board repaired, but you will wind up with one of Sansui's best vintage units.

can the dolby be canceled? And if it could, does this affect its sound?

thanks bro you are better

 

[LBPete]

The Dolby board is an integral part of the preamp and cannot be easily bypassed.

- Pete

 

[kevzep]

The dolby circuits on many Sansui units have proven to be problematic and generally difficult to fix.

Of all the Sansui's I have repaired/serviced/restored which is a LOT, I have not found the dolby circuits to be difficult to repair, time consuming yes, but not difficult, and its typically not the dolby circuit itself, but rather the PCB/Switching that is the issue.

Don't let the Dolby board put you off, if those Dolby chips have been removed, it is an indicator that whoever was working on this did not really know what they were doing, those chips are not a known and/or typical failure point.

500 is a good price and I think with a little bit of work this unit can be brought back to its former glory, possibly better.... I'd go for it, try and bargain it down a bit of course....