toshik said:
OMG!
Do we have people here seriously believing that simple replacement of transistors without changing the dc bias would make the thing sound better???
If you read the whole auction, you will see that DC offset was adjusted, and I'm sure the DC bias was adjusted as well. Replacing the factory transistors with newer MJ or Onsemi transistors is common practice as many of these older transistors simply are unobtanium nowadays. Go and hang around on Audiokarma for a few months and you'll get a feel for what these guys do to restore these things to not just operating performance, but to best the original factory performance as well. Many restores have documented step by step and subsequent testing. For example, one SX-1980 example was restored with some modern transistors and yes, there are challenges to getting them fitted but the final result was tested to produce something around 330wpc (factory specs was 270wpc on the SX-1980). One of the reason for going with replacements is that the factory transistors were obsoleted many years ago already and replacements simply aren't available.
Now, I know you are also against wholesale capacitor replacement and while not nearly as noticeable on boomboxes, I can personally attest that these older receivers simply require it. I did sell several of my receivers about 10 years ago because I needed the cash so I had to sell them. And on those, every single one of them had capacitor issues and either had no sound or wouldn't go come out of protection. This was simply from sitting as they all worked well when I purchased them. Recapping them all was the only way to go and made them sound awesome after adjusting bias/DC-offset. I'm not aware of any boombox employing protection circuits but every single one of these large receivers have a multitude of protection circuits and are very sensitive to out of spec deviations caused by aging components. Every single capacitor would be the same age, and if not failed, certainly failing soon threafter. The hifi audio guys do it and many of the guys on audiokarma are professional techs.
Reli said:
Great unit, but you could buy one of those in bad shape for a few hundred, and then pay a pro to completely restore it for less than $1,000.
As for desoldering the pots to de-oxit them.......Well that's fine, but some pots can't be saved by deoxit.
I disagree, as far as buying them for hundreds goes. This is a Marantz 2600 and I would not be suprised to see a "dead" 2600 with good cosmetics selling for $1500 to $2000+. The Marantz 2500 (looks identical except for the number on the faceplate and a few watts less output) is far more common than the 2600 and even those command very high prices. A quick check on eBay for the 2500 which again, far more common (I have 3 of them) shows a high sold example of $3195 and the LOWEST priced example sold for $1875. Given the rarity of the 2600, the fact that he has done all this work, the current bid of $4100+ is completely justified and probably will go higher. Or at least certainly deserves to go higher. I simply do not believe it is possible (short of an unknowledgeable idiot seller doing a underpriced BIN) to sneak one for a few hundred past all the hi-fi collectors out there. BTW, checking eBay sold listings again for the 2600 shows (2) sold listings, both listings (one auction, one BIN) sold for $6,900.
