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In Reply to: RE: Really don't know. May be it's caused by the Audyn bipol elco caps for speaker crossovers. I have no clue. posted by theob on June 25, 2011 at 07:59:46
Hi Theo,
* caps on the Juli@ digital part
Today I removed the bulky Audyn elco bipolar speaker crossover caps and replaced them with two Oscon 330 uF caps that arrived yesterday (along with the flat ferrites for ribbon cables).
I still can warm boot into 100 and cold boot into 110 – 115 (I don’t know why this isn’t always the same value). So the Audyn caps on the digital part play no role in it.
These Oscon caps again brought a clear noticeable improvement in SQ. Hearing what SQ improvement is achieved only trough changing caps, I think i’m going too closely study how I can power the digital part by battery like you do. I expect some significant SQ improvement.
* About the ferrites on the P24: use them with decoupling caps.
I feel I have a clear picture now on how ferrites on the P24 best can be used. It is just as one can read in several articles: ferrites are best used together with decoupling caps.
So I placed caps on the 3.3 , 5 and 12 volt lines (between the Antec PSU and the ferrites).
This results in a very significant SQ improvement!
Without the caps in place, ferrites on the P24 give a nice little subtle improvement.
But with the caps added it’s a bigger improvement than adding a SSD. So not small!
What is even more astonishing, I do these experiments with the Antec ATX. Because the Pico can’t handle big caps (4700 uF + 47uF + 0,47 uF) on the P24 because pico’s can’t deliver the big rush in currents too the 4700 cap when switched on.
* After 4 weeks of tweaking with ferrites the preliminary conclusion is:
With a lot of ferrites + decoupling caps on the Antec ATX the SQ is very good.
I don’t feel any need too swap the Pico back in place.
The Antex + (a lot of) ferrites + decoupling caps sounds very good too me.
Mark
fully optimized cMP2 PC -> ESI Juli@ -> Van den Hul Optocoupler MkII-> Lavry Black DA10 -> XLR Mogami Gold -> Klein & Hummel O300
Follow Ups:
I added another by pass polystyrene cap across the 5 volt section of Juli@. Yes it added to the sq improvement provided by the ferrites. Thanks Mark!
Hi Theo,
Whow, same thoughts were coming up on the other side of ‘the pound’.
This afternoon I did exactly the same.
And…. with exactly the same results.
I still had some glare. This bothered and irritated me. I thought: may be some extra HF frequency filtering is needed. So I place two extra caps (Oscon 47 uF + 1uF polymer) on the 3.3 V of the Juli@ digital part. See Picture. And … with exactly the same results !
Van on filtering, demping, ect
I like this.
To me it shows these improvements are not random.
If we both independently achieve the same results.
I also did some further experiments with the flat ferrites for ribbon cables.
See picture.
Van on filtering, demping, ect
A ‘pile of charcoal’ works. But also these flat ferrites for ribbon cable work.
However crucial in both situations is: adding decoupling caps too the 3.3, 5 and 12 volt lines before the ferrites (this way a 2nd order HF filter is created (I think))
The effect of ferrites is 4 times bigger, when ferrites are combined with caps.
If one does that, than ferrites really bring a major SQ improvement
More to come.
fully optimized cMP2 PC -> ESI Juli@ -> Van den Hul Optocoupler MkII-> Lavry Black DA10 -> XLR Mogami Gold -> Klein & Hummel O300
I got glare or what I call excess highs so I took the cap out. All this stuff(i.e., tweaking etc) IMO is simply finding a combo that sounds real then stop and listen to music. Then after a few days when you get bored with your sound try something else. Isn't this exactly what a diy audiophile does? Its definitely what I do.
I know that sounds a bit anti science. Let me restate my tweaking philosophy. I believe in the theory of constraints. I learned some of this while working in manufacturing for a while but I think it applies to audio as well. As an example (applied to pc audio tweaking) when one adds a cap to the 5 volt supply on Juli@ like I did) and while it should sound better it doesn't, that means something else is constraining or limiting the output (in this case the output is excellent sound). Anyway when I reach a constraint like this I look elsewhere for what may be holding back a breakthrough to better output. Is my foundation for Juli@ ps as good as it can be in terms of acoustic isolation, is my Buf32s in need of tweaking, etc etc I think you get the idea. But in the end its all about getting good music. Oh by the way while accompanying my wife to Bed Bath and Beyond (a US store for stuff for bedroom, bath, kitchen) I picked up a half inch butcher block which I used to replace my quarter inch plywood base on which I place roller bearings for my Juli@ LiFePo4 battery based ps. And so it goes.
Hi Theo
It doesn’t sound ‘anti science’ too me at all. Sometimes also preconditions first must be met too make something work or too make the effect noticeable.
If you like searching for ways too better sound quality than I have some new not so controversial but also some controversial tweaks too try out if you like.
From reports in the past, I know you have a revealing system that lets you hear minute little changes in sound. Like playing a music file from an USB drive or reducing USB polling frequency. All these are very little improvements in sound quality but your system is able too let them hear too you.
I have 3 new to try.
* First tweak: caps in front and after the ferrites.
This one is not controversial at all. It can be red in almost al articles on using ferrites for suppressing conducted EMI. It is about the using caps together with ferrites
Do some googling on ferrites and capacitor and you will find articles about ferrite based filter networks from Texas Instruments, analog devices, altera, ect.
In there articles can be red that there should be a capacitor in front and a cap after the ferrites.
In front of the ferrites the cap functions as a bypass capacitor to provide a very low-impedance path too ground and thus allow HF noise to pass through to ground. The second function can be to help compensate for voltage droop when the mobo demands large currents peaks.
Also a smal(ler) capacitor is needed after the ferrites too suppress possible resonance.
I don’t have enough knowledge too exactly calculate the values of the the caps needed in front and after the ferrites. So I just tried some caps I had at hand.
I do know that the caps used must have good HF qualities. So I used a standard triplet of caps which I also use on the P4 as smoothing caps. The tripplet is a combination of a Panasonic FC 4700 uF + Oscon 47 uF+ 0,47 uF. I hope the large Panasonic will provide a nice current reservoir and I hope the 37 uF Oscon + 0.47 uF polymer combo will provide good HF shunting.
I placed one such triplets on a 3.3 volt line and an other triplets on a 5 volt line of the P24 (before the ferrites) Too my ears it greatly enhanced the effect of the ferrites (doubled / tripled it).
With these 2 capacitor triplets in place on the 3.3 and 5 volt line in front of the ferrites, I also placed such a triplet after the ferrites. This also brought a noticeable change in sound. But I don’t know if I like what I hear.
So today I ordered some new smal 47 uF Oscons to put behind the ferrites. In litterature I read the caps after the ferrites can be 100 to 200 times smaller than the caps before. See if some smaller Oscons after the ferrites will do the trick.
So if you like tweaking, try and listen how caps enhance the effect of ferrits in your setup.
* 2nd tweak.
This is a controversial one. While just playing with my android phone too move the cursor around through LAN with use of the RemoteDroid server program, I noticed that moving around the cursor added less (EXTRA !) latency than moving the cursor around trough use of the USB mouse. Note: the java server app also ads a bunch of latency. But moving the cursor only ads little extra latency on top of this. Somewhat baffled by this I searched for my old PS2 mouse.
I enabled the PS2 mouse settings in hardware restarted and noticed that moving the cursor around through use of the old fashion PS2 mouse added hardly any extra latency!
-> Now here comes the tweak.
From Reylands I learned that reducing the USB polling frequency removed some glare and ‘relaxed’ the overall sound quality. Reducing USB polling also brought slightly more micro details.
Since moving the cursor around trough use of the USB mouse causes highest (EXTRA) latency off all methods, I thought: why not completely remove the USB mouse? No USB mouse means: no USB polling frequency at all, since all USB ports can be completely disabled in bios and software. No extra separate power needed too power the USB bracket. No matter how clean this extra power too the USB bracket might be, the cleanest power is using no power at all. There is also no possibility that HF noise from the dirty Pico will somehow travel through the USB bracket onto the MoBo via the USB socket.
So I decided too disable all USB root ports in the hardware manager and enabled ‘PS2 mouse’ in the hardware manager. I unplugged the USB mouse connection from the MoBo socket and dirty Pico and disabled all USB in the BIOS.
From memory I can remember that in a standard cMP setup the PS2 mouse sounded a little less.
But now after 1,5 years of power supply improvements and with all USB activity disabled, using a good old fashion PS2 mouse sounds better too me. This can easily be heard.
I know, this almost sounds like blasphemy: telling a cMP user too disable all USB activity unplug it from the mobo socket and unplug it from the dirty PSU and instead reconnect the old fashion ‘dirty’ PS2 mouse and old fashion keyboard.
But never the less: would you like too try and let me know what the effect on SQ is in your cMP setup?
* 3thrd tweak
With the USB bracket removed from duty, the dirty Pico in my setup now only powers the little Kingstone 8 Gb SSD. Since the Pico is also a switcher it also throws HF noise around. May this HF noise can travel through the SSD via the sata–cable onto the MoBo.
So I decided too also place ferrites on the 12 and 5 volt lines that feed the SSD. Because the power lines of the molex connector too the SSD are short I only managed too place 2 ferrites on these lines. I ‘coiled’ the lines around a little paper pellet too make sure that the power wires are tightly pressed against the inside walls of the ferrite when closing the ferrite clamp.
May be ‘the placebo effect’ could fool me, but I think a notice a very slight SQ improvement. Same amount as reducing ‘USB polling frequency’ or playing from USB stick. So very small but noticable.
Let me know if you are going too try some of these tweaks.
Mark
fully optimized cMP2 PC -> ESI Juli@ -> Van den Hul Optocoupler MkII-> Lavry Black DA10 -> XLR Mogami Gold -> Klein & Hummel O300
Hey Mark. I dont have any room on my p24 line for caps or more ferrites so I cant try that. But I do use an old ps/2 mouse and I have put ferrites around the ssd ps. So I already did 2 out of 3.
Excellent follow up, reporting and feedback as always Mark. I'm still good at 140 core speed and .95 v core. I like the sound better than .875 v core and 145 speed...a lot. After a day or so I'll lower speed but feel no need to right now.
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