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Calling All "Vintage" Integrated/Receiver Owners
Jul 30, 2016 at 1:26 AM Post #16,426 of 19,136
vapman said:
 
My apologies, got ahead of myself there.
 
They make super nice level controls: http://goldpt.com/ is their site (check that old school design!!!)
Click to expand...

 
Ah, volume control, ok. Stepped like most vintage ones?
Not going to give any advice as I know nothing on the subject.
Lemme know what you find out tho', interested as well.
 
By the way, is it normal if you turn off your vintage receiver with volume control completely set to zero that it gives a nice thump through your speakers?
Was that the way in the good old times to let you know everything is A-OK?
 
Jul 30, 2016 at 1:28 AM Post #16,427 of 19,136
appleheadmay said:
   
Ah, volume control, ok. Stepped like most vintage ones?
Not going to give any advice as I know nothing on the subject.
Lemme know what you find out tho', interested as well.
 
By the way, is it normal if you turn off your vintage receiver with volume control completely set to zero that it gives a nice thump through your speakers?
Was that the way in the good old times to let you know everything is A-OK?
Click to expand...

Having only experience with a limited number of brands, I suppose this could be by design, but I have a feeling it's either a relay that's supposed to be kicking in but isn't or is somehow overlooked in the design. While it's possible it's by design, my understanding is that with the volume set to zero, turning on and off should be silent.
 
Jul 30, 2016 at 1:38 AM Post #16,428 of 19,136
vapman said:
  Having only experience with a limited number of brands, I suppose this could be by design, but I have a feeling it's either a relay that's supposed to be kicking in but isn't or is somehow overlooked in the design. While it's possible it's by design, my understanding is that with the volume set to zero, turning on and off should be silent.
Click to expand...

 
It's the SX-1250. No idea about the other two, I'm slow at testing.
Didn't test a thing yesterday, only pleayed the same record on the DP-47F with SX-1250 all day long.
Black Sabbath in the Dio years. Heaven and Hell. You just gotta love "Neon Knights"!
 
basshead.gif

 
Sorry, no smiley for headbangin'. Such a huge forum should provide us a broader selection of smileys.
A smiley with an angel for example, fits me exactly.
 
Please report this post to the mods so they are aware there's work to be done. 
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See, I needed the angel smiley now ...
 
Jul 30, 2016 at 3:09 AM Post #16,429 of 19,136
appleheadmay said:
   
It's the SX-1250. No idea about the other two, I'm slow at testing.
Didn't test a thing yesterday, only pleayed the same record on the DP-47F with SX-1250 all day long.
Black Sabbath in the Dio years. Heaven and Hell. You just gotta love "Neon Knights"!
 
basshead.gif

 
Sorry, no smiley for headbangin'. Such a huge forum should provide us a broader selection of smileys.
A smiley with an angel for example, fits me exactly.
 
Please report this post to the mods so they are aware there's work to be done. 
very_evil_smiley.gif

See, I needed the angel smiley now ...
Click to expand...


This guy has before and after pictures of restoring his whole SX 1250, but you might want to check out just the protection board before and afters.
 
http://mattsvintageaudiorepair.blogspot.com/2012/01/pioneer-sx-1250-score.html
 
Some googling indicates the health of the caps has something to do with the reliability of the relay. Those parts in the picture look pretty tired so if I were you (and if you are handy/have the tools) doing a recap and replacing that relay.
 
Should should the same but not spit out a nasty pulse to your speakers upon shutting it off. You don't wanna hurt your speakers probably :)
 
Jul 30, 2016 at 3:27 AM Post #16,430 of 19,136
vapman said:
 
This guy has before and after pictures of restoring his whole SX 1250, but you might want to check out just the protection board before and afters.
 
http://mattsvintageaudiorepair.blogspot.com/2012/01/pioneer-sx-1250-score.html
 
Some googling indicates the health of the caps has something to do with the reliability of the relay. Those parts in the picture look pretty tired so if I were you (and if you are handy/have the tools) doing a recap and replacing that relay.
 
Should should the same but not spit out a nasty pulse to your speakers upon shutting it off. You don't wanna hurt your speakers probably :)
Click to expand...

 
I think the thump is pretty normal. @Skylab should know sice he had a 1250 and now a 1980.
Maybe I should make sure it is witched to the input that was not last used?
 
This is what has been done to mine:
 
Big power caps replaced
All tantalum caps replaced (15)
A few necessary electrolyte caps replaced
A few necessary transistors replaced
Speaker protection relay replaced
Lights replaced
Full cleaning and de-oxidizing
Solder inspection
DC offset and bias current calibrated
Full calibration and endurance test on dummy load and reactive strain (6Ohm + 4uF parallel shunted)
Some minor tweaks
Wood oiled
 
Sorry for the blue lines that are no links, copy/paste from Microbully Word. Blame Bill.
 
Jul 30, 2016 at 9:36 AM Post #16,431 of 19,136
Actually, no, that's not normal or good. If you have an audible thump coming from your speakers when you power up or down, then you probably need to adjust the DC offset. The thump can eventually become so bad that it could potentially damage speakers although more likely in 1250's case, the speaker protection circuit will save the speakers, although it will prevent the receiver from actually working :wink:

Further reading: http://audiokarma.org/forums/index.php?threads/amplifier-distortion-dc-offset-and-you.5634/
 
Jul 30, 2016 at 9:57 AM Post #16,432 of 19,136
skylab said:
Actually, no, that's not normal or good. If you have an audible thump coming from your speakers when you power up or down, then you probably need to adjust the DC offset. The thump can eventually become so bad that it could potentially damage speakers although more likely in 1250's case, the speaker protection circuit will save the speakers, although it will prevent the receiver from actually working
wink.gif


Further reading: http://audiokarma.org/forums/index.php?threads/amplifier-distortion-dc-offset-and-you.5634/
Click to expand...

 
It's not that loud and only happens when powering down. But it is audible.
But if I put the speaker selector to off or to one of the unused speaker outputs there is no thump.
Strange because the speaker protection relais have been renwed and DC offset calibrated like I posted above.
 
Jul 30, 2016 at 5:58 PM Post #16,434 of 19,136
vapman said:
 
This guy has before and after pictures of restoring his whole SX 1250, but you might want to check out just the protection board before and afters.
 
http://mattsvintageaudiorepair.blogspot.com/2012/01/pioneer-sx-1250-score.html
 
Some googling indicates the health of the caps has something to do with the reliability of the relay. Those parts in the picture look pretty tired so if I were you (and if you are handy/have the tools) doing a recap and replacing that relay.
 
Should should the same but not spit out a nasty pulse to your speakers upon shutting it off. You don't wanna hurt your speakers probably :)
Click to expand...

That's the guy I used to restore my SX-1980. He does a really good job, but has a wait list around 7-8 months last I saw. 
Really nice to work with, couldn't recommend him higher.
 
Jul 31, 2016 at 9:33 PM Post #16,439 of 19,136
Not exactly on topic, but I don't think I've ever seen that many portable rigs in one collection.
 
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