How different can some capasitors be? Panasonic alone has several different series. I don't care for fancy names like the Black Gates or what have you. I do care about build quality and I know from other areas that the Japanese are insanely good at quality control (I don't drive Honda's and Toyota's for nothing). Mike, I think your priorities and common sense are spot on. And the fake Krugerand is very funny as long as it isn't your money wasted. If it sound to good to be true, it probably is.
I wonder what a x-cans would have cost more if they had put in some panasonic and other quality stuff in there. If bought in bulk (they made a lot of these cans) it can't be a lot. But as you said, the reviews were great and the thing has to make money and in a few years it has to fail so they can sell you another one. As far as my cars go, I'm not good for the Honda company and Toyota corporation (I have two cars). Both of them have driven around 280.000 km with minimal failures. These cars are (allmost too) well build. I spoke to a Toyots salesman a few years ago when I had a Toyota Starlet diesel. He sighed (?) and said it was so well made it doesn't break down and let him sell me a new car. He said "if you can keep the oil in the engine, it will run a million km".
So panasonic is a good choice for me in the x-24k. But what are the differences between the FC, FM, FR and NHG series. I read in a panasonic document the FM series has lower impedance than the FC series. That changes the characteristic of a circuit board, right? And these impendances are probably lower than the Jamicons as well. Doesn't that make the circuit run warmer because of the higher current?
I measured and the capacitors can be as high as 5 cm. But there doesn't seem to be panasonic elco's that are high and have a diameter of 12 mm. Going 16 mm in diameter is a possibility but then the pins are 7,5 mm apart. That would be a gamble.
I was wondering. The x-24k has some room above the capacitors at the back of the can (the power supply section). Because of the diameter of capacitors it's quite difficult to place big ones. Is it possible to make a little construction where several capacitors can be fitted. So replacing each of the current 6 with 2 so making 12 in total. I was thinking if these can be best placed in series of parallel circuit. I would think in parallel because of the lower resistance.
What do you think? (If I'm a blithering idiot for suggesting this, please say so).
I just happen to have one of these in pristine condition at hand (I bought it almost twenty years ago and it's like new), and I'll probably try to mod it soon so I can get a bit more transparency out of it, now it sounds warm and very listenable but I miss a bit of clarity (comparing it to good modern designs). Anyway for such an old unit it still sounds surprisingly good, full and warm.
Regarding power supply caps, I think that there's already enough capacitance in the original design, since these are pretty old, replacing the caps may be beneficial, but these units run pretty cold, not even luke warm at touch, so heat is not a problem at all unlike the X-Cans units or other tube amps.
Probably the most beneficial mod would be to remove and bridge the two 47uf bipolar electrolytic caps (measuring DC would be wise but maybe unnecessary if the amplifier that the DAC is connected to already has input caps), and maybe bridging the two muting transistors (that may cause pops and clicks).
I have removed the electrolytic caps that are part of the high pass filter at the output of several DACs with good sonic benefits, however removing the ceramic caps that seem to act as part of a low pass filter will probably be a bad idea, maybe replacing them with better caps or changing values to alter the cutoff frequency will render benefits, but with old DACs changing the values and altering high frequency response may not be a good idea since there may be quite a bit of quantization noise.
YES..... I have one in at the moment and that's the way it left the factory.
That is 100% a factory job Nando.
I'm doing a simple re-cap (removing the tantalum capacitors.... one of them blew up / as they tend to do in a slight over voltage scenario / situation)..... basically recapping the X-24K....... photos to follow.
I fear I might have left it as it was. A t the time it was no concern for me because it worked with this connection there.
Easy enough to remedy...... it looks like a piece of unmelted solder to my eyes?
Yes, it looks like that doesn't it? That's why I photographed it then and posted it here. So I better remove that blob of solder then? Wonder what the my x24k might do when I remove it... Might be an easter egg from an MF employee.
This one came in with a blown tantalum capacitor so the best course of action was to replace all of the tantalum caps and electrolytics. A new lease of life for the old girl (or boy)...... sounds pretty damned good too! No point replacing the one solitary blown tantalum capacitor and charging a fortune...... I replaced them all (tantalum and electrolytic) with quality capacitors and charged what MF would have probably asked for replacing a friggin' resistor Pretty much peanuts BUT it's not all about "money", I'd rather take pride in my work and be able to sleep at night rather than rip people off.
Anyhoo..... a few photos added to your thread Nando hope they help any fellow X-24K owners who need help
Those double sided boards are little buggers to work on aren't they? The larger pads were a breeze but the 47uf / 16V tantalum pads were little bastards! I find the best technique is to desolder as much of the lead free gunk as you can from the pad, with the cap in situ, then add more heat and yank the capacitor out whilst applying force...... once the capacitor is removed flood the pad with some 60/40 (lead rich) solder and you'll find it sucks it up in one (or two) goes....... that unleaded stuff is hideous stuff to desolder on a double sided pad joint so keep that in mind if you ever decide to remove the tantalum caps Nando.
videoguy: Hi Jon: I am in Florida & am in frequent contact w Alex Kethel. Am in need of some single ripple eater boards. Wpuld you mind giving me the address of the pcb manufacturer; as I need ten boards. Thank You in advance. Bill Wilson
Dec 2, 2019 1:54:46 GMT