I wonder too. The poor things seem like the lowliest of all components. Not real pretty & not much press time like the electrolytic rage going on now.
I don't see ads for esoteric audiophile ceramic discs. There must be some though........
No, I had to replace that cap because the PLL was in free running mode ( no lock )
It was an issue and I replaced it with an other ceramic cap .
No improvement , only a repair .
It is unbeliavabe to find a wrong ceramic cap , due to their long life span .
Regarding PL 4000 , after recapping, no difference in sound .
Instead for Dynaco PAT 4 , probably there was an improvement .
But consider also that PAT 4 power supply is a " strange " circuit .
Unregulated power supply with 2 diodes rectifier .
As with most analog tuners they tend to drift with age. Over the years, I had the opportunity to watch Dean perform his magic on many a 5000 and 5100. I haven't seen a 5000 yet that has met factory specs. Unless of course someone else has done a recent alignment (say within the last 10 years). They all need a complete FM alignment. I have a Sound Technology 1000A, 1100A and 120. I hope someday soon to start working on my own tuners.
One of the most common problems with the 5000 is with the 390pF ceramic disc capacitor C22 located next to R39. This capacitor will go down is value by about 30pf. That is enough such that there isn't always enough range of adjustment with R39 in order to bring the 19kHz clock within the factory spec of +/-100Hz. Typically, old 5000's are off by around 1000 Hz. Dean would usually just tack/solder a 30pF cap on top of the existing cap.
With a properly operating 5000 tuner, you should have the signal strength at its maximum, the center tuning should be centered and the (19kHz) stereo pilot light should be illuminated. You shouldn't have to tune any of these parameters off center in order to obtain a better condition of any of the others.
A.P. Van Meter designed the Phase Linear 5000 tuner. A.P. had previously worked at McIntosh just after he graduated from the University of Oklahoma. A.P. was on the ground floor of FM stereo in late '61, early '62. He has a bunch of interesting stories about those early days. I had a McIntosh MX110 tube tuner/preamp that A.P. had a hand in designing. His name is also on some of the schematics.
To be honest Dynaco FM 5 ( 1972 ) has a PLL called Dynatune !
I have this tuner and it works very well .
Probably LM 1800 is the first IC that performs both FM mpx demodulator and PLL in the same case .
Regarding AP Van Meter I don't understand why he did not use the Hi blend filter function .
It' only one cap circuit . Oh , question mark !
I think MUSE caps are for those who don't like to read data sheets. They only have 1000 hours endurance at 85C. I don't believe they are designed for low distortion either. If they were, there would be specs in the datasheet. Even with a DC bias, bipolar caps have lower harmonic distortion than polarized. Bipolar caps are double anode - no cathode. So you have to ask yourself "Then why are there MUSE polar caps?" The obvious answer is Nichicon does not measure distortion. They do have great marketing so you feel good about buying their caps.
Well I will tell you the Nichion caps are great and they sound excellent. The ES bipolar caps have some true improvement when used in the sound path. Thousands of people have supported this conclusion. Many on the fm tuner site like to use them in their radios. These are the toughest critics you will ever meet. All of Joe’s Whitoak boards have some MUSE caps. I use Nichion KA series for power supply and buffers.
As to service life Nichion’s spec said that after so many hours at such a temp(high) that the cap will perform to spec when returned to 20C My C-4000’s and 4000t are had pressed to get to 25C.
Nichicon has not provided any specs or test data to substantiate what makes MUSE caps sound better. Polar caps have more distortion that bipolar even with DC bias, so why are there polar MUSE caps? That tells me Nichicon does not measure harmonic distortion under load. Also MUSE caps have lowest endurance of any electrolytic. It makes me think Nichicon is cycling audiophiles through expensive caps by using advertising. Truth probably is all their bipolar caps sound good.
It's all about choice. I can buy a car for 20 grand which is just as dependable as the 40 grand one I bought. But I stick with the brand I bought because it has served me well for the last 25 years. And it is pleasing to the eye, and the ear.... If you want cheap caps, buy cheap caps. It also keeps the customers happy to see the pretty stuff when the open it up. It's all good. I'd hate to tell them that I'll lower the price by using the cheap stuff. Even if the cheap stuff works just as good. As long as the Nichicons do their job and do not ruin the sound, I'l keep on trucking. I see the specs too and if one of my pieces is run at 185 degrees Fahrenheit for 1000 hours, many other components are going to suffer as well. Won't have to worry about just the caps....... it will let the smoke out of a bunch of shit. Maybe we should stick a preamp in the oven for 42 days @ 200 degrees and see what else fails (all while plugged in).
That's actually a well thought out response. Thanks.
Customers see green caps in place of formerly black caps, are told the MUSE brand, and they check off the box.
Doesn't matter that they won't last as long as a 2,000 hour cap. They don't want to hear it.
So why change anything?
People in the know will use UVP series bipolars with longer life for their own gear.