Replacement Parts for Quad 909

Disabled Account
Joined 2002
You are on your own with the task to do the unimaginable.......to find out which resistor is best for your 909..... Tip: just leave those resistors where they are if they're simply functioning OK. If they are resisting then do what you have to do.

What's next ? The mains connector ? ;)
 
Sure nothing wrong with a rhodium 20 amp IEC socket lol, actually there is also a cut out switch next to the power socket, I might bypass this and hard wire direct.

I intend to experiment for my myself and solder some different resistors, just trying to get some opinions on what people recommend.
 
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Disabled Account
Joined 2002
As you can have read I am not too shy replacing parts in a well thought out way but no I haven't noticed differences in wirewound resistors. Please note that I only choose industrial parts from well known good companies so no name stuff (nor boutique stuff in most cases). I doubt there are much differences. These wirewound resistors are used where heat must be dissipated. A metal film of the same wattage would be too large.

When I think of it...I have experimented with non inductive wirewound resistors where they could be applied (emitter resistors in power amps). I won't study the 909 to see if those can be applied, there are things in life one must do oneself.

I would advise to use good bipolar electrolytic caps for C7.
 
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Disabled Account
Joined 2002
True if you make that bent statement. More expensive is not a guarantee. It is about part properties.

This also holds true:

"People who want to change perfectly good working standard components for higher quality (= better measuring and sounding) components are more satisfied listeners".

Some will want to change perfectly good working cheap standard parts for better quality parts and there is nothing wrong with that. Sometimes their price is nearly the same. Why on earth am I blessed with that knowledge for more than 30 years ? Because I simply tried. I modded hundreds of devices with satisfied "customers". Polypropylene caps do sound and measure better than MKT/MKS. Most film caps sound way better than electrolytic caps in the signal path i.e. at the input of amplifiers and such. This is so obvious and known by many DIYers that it almost is a common truth. So common that manufacturers of quality gear use film caps at that spot. Why not try out ? Afraid to change religion ? Conservative ? Afraid of the dark ?
 
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Disabled Account
Joined 2002
Sarcasm and cynism are not the best instruments to make a point.

Did you already do the MKT/MKP test ? Takes only a few hours of your time. There are no laws against it. Come on show us some "wir schaffen das".

It is so laughable that it becomes sad. Anyone with good ears can hear differences in caps. We sold around 700 PCB's (or 800, I forgot the exact number) of a DAC design to members. Many builders suggested other cap choice over the recommended caps. I took the challenge and tried many of the suggestions and noticed improvements. Some negligible, some not so negligible. There was a best cap for decoupling the negative power supply created by a charge pump in the DAC chip for instance.
 
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Disabled Account
Joined 2002
I don't believe in snake oil, I believe in science. Neverheless my ears have an opinion too.

If there is time and motivation to try out and things improve then it is nice when science can explain why this is. If not then it is still fine with me. Stubborn nay saying does bot keep me from empirical testing. An open mind is a joy forever :D
 
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I don't believe in snake oil, I believe in science. Neverheless my ears have an opinion too.

If there is time and motivation to try out and things improve then it is nice when science can explain why this is. If not then it is still fine with me.

As i say before the key factor in both is "believe".The science doesn't exist if u don't believe.
 
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Disabled Account
Joined 2002
No. As we say here: believing should be done in church.

It is not a matter of believing, it is a matter of wanting to accept. And the willingness to spend some time for trying out and finding an explanation. Best is when the oscilloscope shows a clear difference (as observed many times with decoupling caps on XO's for instance)
 
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I wish I still had good ears, I probably wouldn't hear the difference anymore, but I'd go for the wima polyprops out of principle because they are better so why not and like I said earlier they look better too, particularly alongside the beautiful nichicon muse, would you like to see a picture?