|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
195.218.197.22
In Reply to: RE: Question re your pure linear PSU posted by cics on April 07, 2010 at 01:10:08
Thanks for congratulations, cics!
1. Unfortunately there was no possibility to compare these two cMP2 directly yet. (About testing cMP2 later)
2. Connector P24: pins 1,2,12,13: +3.3 V; pins 4,6,8,9,21,22,23: +5 V; pin 10,11: +12 V; pin 14: -12V; pins 3,5,7,15,17,18,19,24: ground. I have placed two more photos in My gallery.
3. Switch on the mains switch on the zalman's rear panel (see IMG_0628_ in My gallery), push the power button on the zalman's front panel, that's all!
4. No, imho. Because the linear psu has low efficiency in comparison with the switched-mode psu and produce a lot of heat, hence it requires adequate cooling.
5. Yes.
Edits: 04/10/10Follow Ups:
Seen the additional pics and your writeup on comparisons & improvements is useful.
I see P24's purple wire is ignored - only power lines (3, 5, 12 & -12) are connected. -5V is ignored. Actually based on your pin descriptions, you have implemented a P20 connector which should work. ATX 2.x P24 layout:
There's 100% match after renumbering pins 13-24 to 11-20 in above diagram: pins 1,2,11: +3.3 V; pins 4,6,8,19,20: +5 V; pin 10: +12 V; pin 12: -12V; pins 3,5,7,13,15,16,17: ground. Here's P20 layout:
How is it that you don't need a power up sequence? Pin 8?
I think one has to settle with an external PSU - perhaps its better. I would prefer the unit with 2 AC inlets (1 for P20 another for the rest including P4). Can one have this design produced in limited numbers?
About pinout of connector P24 - I certainly was mistaken and have already corrected my previous message. Thanks, cics!
-5V is ignored - yes!
+5V Standby isn't ignored
"How is it that you don't need a power up sequence? Pin 8?" - I don't know, but it's OK! All voltages (pins 1,2,12,13: +3.3 V; pins 4,6,8,9,21,22,23: +5 V; pin 10,11: +12 V; pin 14:-12V; pins 3,5,7,15,17,18,19,24: ground) are supplied to the connector P24 SIMULTANEOUSLY by mains switch and THEN push the power button on the zalman's front panel.
"any way of producing that PSU for others?" - I am going to upload the documentation which will help to make such PSU.
"unit with 2 AC inlets (1 for P20 another for the rest including P4)" - Sorry, but I havn't understood that you meant: two ac inlets for two power cables ?
Would you please be so kind to give us the "shopping list" for your P24 and P4 PSUs?Also - I am not sure if cics was reffering to that in his question - there is a particular switching on sequence for motherboard and cpu. How did you deal with that?
Could you please let us know about your listening experience with this system, perhaps compared to another cMP2 system you may have had before.
Thanks a lot and congratulations again!
Edits: 04/08/10
Unfortunately now there is no time to answer all questions (I will try to make it during week-end).
About "particular switching on sequence for motherboard and cpu". All voltages on P24 and P4 are supplyed simultaneously by switching on the mains switch on the rear panel of the case (see previous my message, item 3).
It would be great if, together with the "shopping list", you could provide us with a diagram/layout of the elctronics. Of course, if you are willing to make it public, like cics has for his project.
Thanks.
I have uploaded the document. See link below.
Edits: 04/14/10 11/04/10
Many thanks to Mihaylov for sharing the design of the linear PSU. Excellent write-up, but on page 6 there are a sentence in Russian I presume. Can you please translate?
Took quite a few attempts before successfully downloading the file.
I second smicyta's request about Russian sentence on page 6 as it is about the fourth important psu for services like HD, monitor, usb...
Looking at the PDF I can only renew my congratulations and thanks.
I am sorry. I hurried up and has forgotten to remove the Russian text from the final version of the document. The Russian text can be ignored, because it is translated in the following sentence.
I want to add this to our cMP² site. Problem is its size at 24.8MB - compressing doesn't help. Only way would be to use smaller pics with lower res.
There will be 2 sections added under "Advanced":
1. Pure linear PSU (as per pdf)
2. Replacing Juli@'s XO
I have uploaded the compressed version of this document (3895 KB). The quality has not degraded almost.
Edits: 04/17/10 11/04/10
Tried pdf, html, but for some reason it has "errors converting document"
Anyone else not getting it or is it just me??
Thanks guys I got it. The LINK didnt work, but the addess did it that makes sense.
Click link, click free user then wait for timeout, click download, click save and save to file on PC worked for me on home and office PC.
Brad
.
Thank you for sharing this info. Haven't had a chance to go through it but will. Maybe cics will host it on his site.
Thanks to both of ya'll.
Brad
Here is the sound test of cMP2.(Excuse me for probably bad English)Сontrol sound section:
- A control source of a sound: cd transport CEC TL5100 (thoroughly upgraded in a power supply: two toroidal transformers, some voltage stabilizers are added, electrolytic capacitors are replaced with capacitors Black Gate of different series, established the copper screens separating psu, the mechanism, the display and the main board from each other)
- DAC: Musical Fidelity A3.24 (output capacitors are replaced with BG NX)
- Integrated push-pull tube amplifier ART AUDIO LAB m25 (Tula, Russia) (the absolute upgrade is made: external psu on two kenotrons, supplying input and output cascades from separate windings of the transformer; wiring of an anode supply and input circuits of the amplifier by silver wire Jensen; all sockets WBT; a regulator of loudness ALPS Blue Velvet; capacitors BG, Jensen, Elna Cerafine; resistors in grids of input tubes Riken Ohm; four-stage adjustment of feedback depth is made)
- Loudspeakers: Klipsch La Scala 2 (a small upgrade: all "automobile" demountable connections in internal wiring are replaced with solderings)
- Cables: power: self-made, made of an inexpensive acoustic cable; digital coaxial: Supra Trico 1.0m (BNC - BNC); interconnect: Ortofon Reference 8N-1m; acoustic: Nordost Blue Heaven - 2m.
- cMP2: "black case" configuration but with hdd 1000ГБ Western Digital Caviar Green1. Sounding сМР2 with computer psu (Antec EarthWatts EA 430W)
Sound is dry, etched that is called with the "sand", abounding with the false detailed elaboration distracting from perception of a musical material. A sound is superficial, as though deprived of density. On difficult fragments of products of classical music sounding frequently formal, laid-back. An involvement into listening is low, in a consequence of that listening classical music is simply uninteresting. As a whole the control source beat сМР2 though lost to the last on some parametres, such as the resolution and depth of a stage.2. Sounding сМР2 with completely linear psu.
The occurred changes in a sound can be characterised as critical: the sound from the cheap ("computer") has changed in the costly, close to an analogue source on character of sounding . Sounding became more dense, perceived, the "roughness" and "sand" have practically disappeared, was showed timbre saturation, "beauty" of music. The involvement into listening has considerably raised, the perception of a musical material was facilitated. At high levels of loudness fatigue from long listening is small.3. Sounding сМР2 with completely linear psu and a precision external clock.
The changes which have occurred in sounding in comparison with item 2 to describe difficult enough. On the one hand this changes seem small, with another - strongly enough change a picture of perception of music. Such audiophile characteristics as localization, resolution, dynamics have certainly improved, but it seemed, what not this main thing in the occurred change of a sound.
The sound became, if so it is possible to be expressed, crystal, but not in sense firm and cold, and even more transparent, harmonious, "tasty". In general it is much easier to hear all it in real sounding, than to describe in the standard terms. The impression was made, that other sound-reproducing path slightly limits source possibilities. It is necessary to notice, that cMP2 became very critical to quality of supply mains voltage. I attribute it to the increased resolution and a transparency of a source of a sound. Replacement of a power cable on good firm one (Cardas Audio Golden Reference) cardinally improves all picture of sounding. In this case it is possible to speak about a power cable as very important part of an sound section. The source transparency is that, that allows to test easily quality of mains switches,preventers, filters, plugs, sockets etc.Conclusion.
cMP2 (last update) beat the control source of a sound practically at all items. Some nuances of sound reproduction which are present at both sources and are undescribed in the given test, concern the category personal listener's preferences.to be continued...
Edits: 04/09/10
4. Sounding сМР2 with completely linear psu, precision external clock and SSD 500 Gb SATA-II OCZ Colossus Series.
The changes in a sound:
- The resolution at silent levels of a sound has increased. It seems that a bass became less, but the resolution of a bass and its quality has sharply increased, it became accurately delineated, the stereo effect in a bass is easily distinguished. The nuances of mastery are more clearly shown.
- The advantages of SSD (in comparison with HDD) are shown more considerably on more difficult musical material though are appreciable on anyone.
Edits: 04/09/10
Very awesome system and very articulate description!! Your english is superb, congratulations.
Thanks for warm words, theob!
did you make a comparison of pure linear psu with external clock vs CEC TL5100?
Which is better?
cMP2 with pure linear psu and external clock is better
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: