C353 and C354 appear to be connected to the two ends of the crystal, and to ground. This is the normal oscillator arrangement for digital circuits. They will be low value, typically 10's of pF, and could use various dielectrics. They will not be polar (and not "bipolar"). Possibly NP0/C0G? There is no reason to change them unless they are suspected to be faulty.
Hi DF96, this was the initial argument that some people in forums have tried replacing those with silver mica and reported great results, half as much as upgrading the clock itself.
The problem is that my cd player is broken otherwise I would have tried it myself. Those caps looks really cheap I mean wouldn't Wimas polypros be better?
The problem is that my cd player is broken otherwise I would have tried it myself. Those caps looks really cheap I mean wouldn't Wimas polypros be better?
People replacing X with Y (where X and Y are electrically very similar, although employing different technology) usually report great improvement. In many cases the best way to genuine improvement is to use a better crystal. Whether this will be audible is a separate issue. Clock 'upgrades' may degrade things due to interfacing issues.
If caps make such a big change in audio path and power wont it for crystal? I have no idea if I'm saying stupid here lol
I just read on a forum that mica made huge difference and if anyone had experienced with it. My ears are pretty in tune so when I get the chance I will try it just thought someone else tried it already or is going to try it. Changing the whole clock is a bit beyond me..
I just read on a forum that mica made huge difference and if anyone had experienced with it. My ears are pretty in tune so when I get the chance I will try it just thought someone else tried it already or is going to try it. Changing the whole clock is a bit beyond me..
The idea of a crystal is it oscillates at set frequency.
The capacitors just load the crystal to stop the crystal oscillating at a higher frequency harmonic.
For a 20MHZ PIC clock 18pf is specified. It doesn't matter if it is silver mica or ceramic as long as the capacitance doesn't change over normal working temperature.
If the capacitance did change the frequency then that is a lose big time !
The capacitors just load the crystal to stop the crystal oscillating at a higher frequency harmonic.
For a 20MHZ PIC clock 18pf is specified. It doesn't matter if it is silver mica or ceramic as long as the capacitance doesn't change over normal working temperature.
If the capacitance did change the frequency then that is a lose big time !
I am pleased you started your sentence with 'if'. Changing caps make very little difference, unless the original caps were faulty or inappropriate.dj_holmes said:
Don't believe everything you read on forums. For a small value capacitor used in an RF oscillator there is little to choose between silver mica and C0G/NP0 ceramic. 50 years ago people would use SM; nowadays they use ceramic.
Given the option, most crystals will naturally oscillate on their fundamental frequency rather than an overtone. The capacitors are there to combine with the inductive impedance of the crystal to give an extra 180 degrees of phase shift so the result is positive feedback. The value of the capacitance will vary the frequency but only by a small amount so the quality of the capacitor is actually not too important in a crystal oscillator, within reason. It is a feature of audiophiles that they worry the most about things they don't understand, including things which don't matter very much.nigelwright7557 said:
If I get my cd player fixed anytime soon I will post resultsYou need to be aware that in audio people change what they can; then declare that such a change is important and beneficial. For some this is cables - almost always hugely unimportant. Once they learn to solder then they swap components - usually capacitors first and then resistors - mostly a waste of time. The thing which can actually make a real difference (the circuit) is either beyond them or they rely on things they heard from a man in a pub (or the modern online equivalent).
It is possible that a new clock might be better, as there are better oscillator circuits than the 'inverter' circuit used in most digital systems. However, the difficulty in correctly interfacing an external clock to the existing circuit means that even a perfect external clock might sometimes give inferior performance to an imperfect internal clock. In many cases the simplest genuine improvement may be putting a better quality crystal into the existing circuit. However, even this may not be audible.
It is possible that a new clock might be better, as there are better oscillator circuits than the 'inverter' circuit used in most digital systems. However, the difficulty in correctly interfacing an external clock to the existing circuit means that even a perfect external clock might sometimes give inferior performance to an imperfect internal clock. In many cases the simplest genuine improvement may be putting a better quality crystal into the existing circuit. However, even this may not be audible.
And sometimes, a poorer Crystal but sorted out like some guys do (Jocko) will give better results than many expensive ones which are giving poor result at the end at the day because decoupled around with ceramic class II X7R instead of COG/NPO ! But I have to admit I heard that in a bar when drinking a beer...
Where is Jocko?
I was in Dallas last weekend and thought about Jocko. Is he doing okay?
I was in Dallas last weekend and thought about Jocko. Is he doing okay?
Can one use low K ceramic as Y5R or even some "slower" caps as smd solid tantalum ?
What about bigger Tang loss of X7R vs C0G, but also lower inductance because lowest case size ?
Find always the X7R MLCC brings a sharp & edgy sound ! More "relaxed" tan loss is better ? Or old ceramic disc caps ?
Indeed the OP should not change things ! A newer xtal can be worst... (imagine this one is already good by chance - I mean in the sense Jocko Homo wrote some AT Cut are sota after measurements (for sorting out), but few in a bag of 1 000 units). And this Xtal has not cosmic speed at 16 M Hz, old & stable is certainly good enough here.
Lost time. Better to start around a newer layout with a cheap DAC kit for DIY Learning. DF 96 is right.
What is the dielectric of the two littliest caps near the xtal on the op's picture ?
What about bigger Tang loss of X7R vs C0G, but also lower inductance because lowest case size ?
Find always the X7R MLCC brings a sharp & edgy sound ! More "relaxed" tan loss is better ? Or old ceramic disc caps ?
Indeed the OP should not change things ! A newer xtal can be worst... (imagine this one is already good by chance - I mean in the sense Jocko Homo wrote some AT Cut are sota after measurements (for sorting out), but few in a bag of 1 000 units). And this Xtal has not cosmic speed at 16 M Hz, old & stable is certainly good enough here.
Lost time. Better to start around a newer layout with a cheap DAC kit for DIY Learning. DF 96 is right.
What is the dielectric of the two littliest caps near the xtal on the op's picture ?
If you are asking me I have no Idea. I would imagine its as cheap as possible!
Ceramic class II so X8R and below have two major defaults as far I understand for audio circuits :they are piezzo and related to this they bond on the pcb circuit when a voltage are apllied on it creating a small not wanted voltage interaction! Some noticed bad effects on sound ! Certainly sometimes it doesn't matter and sometimes the opposite ! I don't know either of the dielctric of the two little yellow capacitors, but if carbon despite more noise it can has better behavior at highest frequency than metal film and maybe this is what looked for the engineers ! Sometimes often costs matters and just the basics are a concern : a resistor is a resitor, the cheapest matters !
But without knowing as said DF96, just avoid ! Problems can occur : for instance a styrene must be soldered at relativly low temperature as it's fragile and very rapidly not to break or degrade it, and the most basic sounds crap ! And anyway it sounds not good for several hours after the soldering ! As far I know the silver mica has not this problem but maybe a little brillant in some hifi and in some other hifi this can not be notified !
SMD mica caps has better inuctance than the bulky radial, etc; so changing the little one by biggest is maybe not an idea : you are in the dark dying like that !
But without knowing as said DF96, just avoid ! Problems can occur : for instance a styrene must be soldered at relativly low temperature as it's fragile and very rapidly not to break or degrade it, and the most basic sounds crap ! And anyway it sounds not good for several hours after the soldering ! As far I know the silver mica has not this problem but maybe a little brillant in some hifi and in some other hifi this can not be notified !
SMD mica caps has better inuctance than the bulky radial, etc; so changing the little one by biggest is maybe not an idea : you are in the dark dying like that !
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