[Silent One]

Quote:

About the scratchy static - it sounds kind of like you're describing radio interference from a cell phone. I'm not totally sure though from your description. Does the "static" have a pattern, or is it just randomly appearing white noise? If it's completely white noise, then it could be a preamp issue.
 
Also - I absolutely LOVE the blue lights on my Kenwood KR-9600. It is so nice to look at when it's on that I had to really debate my decision to list it for sale. I just WANT it to sound better than my SX-1980, even though it's just a little warm.

 
What... wait, you might be selling your SX-1980? We gotta talk!

 

[Argybargy]

just asking. were receivers in the 70's/80's dead quiet like today's, or is the small hum normal? my harman kardon 430 has a horrible hum on all inputs and settings but the phono input has it the worst and Treble knob really makes it bad. The KR-7400 has a small but noticable hum with my Beyerdynamic DT990 600ohm and AKG K702. I really like these vintage receivers, they make the drivers in my headphones actually move and produce wonderful sound unlike modern stuff I have like Nuforce icon HDP/UDH-100/Schiit Valhalla.

Your HK 430 is probably around 40 years old. If the main filter caps are original you are probably hearing the transformer and the big caps are bad.

 

[Argybargy]

Even after a complete recap vintage receivers can have slight hiss or background noise due to old diodes and transistors. However if you use low sensitivity phones like orthos, you can get a silent black background.

 

[harrinj]

Quote:

Your HK 430 is probably around 40 years old. If the main filter caps are original you are probably hearing the transformer and the big caps are bad.

everything is original. it was my parents and lightly used. it was bought in the 70's so yes 40 years or more. I have been debating on taking it in to get fixed. it's got wonderful sound minus the buzz/hum. I've sprayed deoxit over everything and cleaned everything up fine/replaced fuses but it did not help.

 

[parbaked]

Quote:

Originally Posted by harrinj
 /img/forum/go_quote.gif
 
everything is original. it was my parents and lightly used. it was bought in the 70's so yes 40 years or more. I have been debating on taking it in to get fixed. it's got wonderful sound minus the buzz/hum. I've sprayed deoxit over everything and cleaned everything up fine/replaced fuses but it did not help.

This is a typical repair list that is required for a 40 year old receiver/amplifier that has not been abused:
 
All controls and switches have been cleaned and lubed.
All electrolytic capacitors have been replaced on all boards. (Caps for Filtering=NichiconPW/Signal Path=Silmic II)
Any transistor that has been noted for being problematic has been replaced with new matching spec transistors.
The power light has been replaced.
Bias and offset have been set to factory specs.
Main filter caps were replaced with Panasonic THA Computer grade caps
There were 10 tantalum caps that can go noisy that were removed and replaced with Elna Silmic II
Please see the pic of all the components that have been replaced.
The 2 small caps on the protection board were replace with Panasonic ECW polyprop. film caps.

 

[harrinj]

Quote:

This is a typical repair list that is required for a 40 year old receiver/amplifier that has not been abused:
 
[size=13.0pt]All controls and switches have been cleaned and lubed.[/size]
[size=13.0pt]All electrolytic capacitors have been replaced on all boards. (Caps for Filtering=NichiconPW/Signal Path=Silmic II)[/size]
[size=13.0pt]Any transistor that has been noted for being problematic has been replaced with new matching spec transistors.[/size]
[size=13.0pt]The power light has been replaced.[/size]
Bias and offset have been set to factory specs.
Main filter caps were replaced with Panasonic THA Computer grade caps
[size=13.0pt]There were 10 tantalum caps that can go noisy that were removed and replaced with Elna Silmic II[/size]
[size=13.0pt]Please see the pic of all the components that have been replaced.[/size]
[size=13.0pt]The 2 small caps on the protection board were replace with Panasonic ECW polyprop. film caps.[/size]

yea the first one has been done more than once. the rest I cannot do. I will have to take it somewhere to get this done. I am afraid it will lose it's good sound though. what do you think?

 

[parbaked]

Quote:

yea the first one has been done more than once. the rest I cannot do. I will have to take it somewhere to get this done. I am afraid it will lose it's good sound though. what do you think?

If cleaning doesn't work then you have to start replacing the 40 year old parts that are known to go bad or are tested bad.

 

[SpeakerBox]

Quote:

Thanks, I actually considered my cell phone so I always have it a good couple feet away from my Marantz. The static has no pattern whatsoever to the point that it is extremely hard to reproduce the problem when I try to show it at a repair shop lol. I've considered the possibility of my computer or router causing the issue too but I can't tell for sure. The static is as you said, random. 

 
Have you tried just shutting down all computers, routers, phones, etc.?  Just to see if it still happens.  Process of elimination....
 
That said I have seen this happen with both failing transistors and failing capacitors.  Can be hard to find out which one is doing it.  Sometimes cooling/heating a component will make it stop or start.  If a capacitor is starting to fail sometimes it will just discharge all of a sudden or a transistor can start to oscillate.  But as you know, the question is which one?   Sorry I can't be more helpful.

 

[PhoenixG]

Quote:

 
What... wait, you might be selling your SX-1980? We gotta talk!

Sorry - The KR-9600 won the battle on looks but lost the war for shelf space and is for sale instead. 

 

[SpeakerBox]

Can anyone tell me if the KOSS ESP6 HP is any good?  There is a pair on CL near me for $25.   Just curious.

 

[SpeakerBox]

Quote:

Can anyone tell me if the KOSS ESP6 HP is any good?  There is a pair on CL near me for $25.   Just curious.

Ok, got the answer in another forum.  Sounds like it is not a good investment.

 

[thyironman]

Hi everyone!
Will the headphone out on a Technics SU A900MK2
drive my 600 ohm dt990's properly?
 
I have a chance of getting one for free but it means having the thing sent to me from another city, so i'd like to get some advice on the prospects of this combination.

 

[parbaked]

Anybody have any Pioneer Specs? I found these images in an ad to sell custom the racks...
 
 

 

 

 

[Silent One]

Well, if I didn't fully wake-up the first time 

 this morning... that's some Pioneer glory.

 

[PhoenixG]

Quote:

Anybody have any Pioneer Specs? I found these images in an ad to sell custom the racks...
 
 

 

 

Wow. If that doesn't make your heart palpitate, I don't know what will.