Almi's Logitech Z-5500 Mod (High-End upgrade for the speaker system)

Jun 7, 2014 at 1:56 PM Post #46 of 561
Update: today i swapped back the original pre-amp capacitors, and the sound definition in lows is back again! This surprise me a lot, because everyone in the audio forums, thinks ceramics are the worst thing to the audio!? But i found them to be much better to the MKS2. I know the polyesters are not that great either, but i thought everything else is better than ceramics. As it turns out in my case they are good. For now i am planning to keep them, at least, till i find something really better. They work extremely well with panasonics, bass is very well defined and the panasonic caps add some very pleasant softness to it. Its much more to my liking! Nice!
@jayjayuk, why you are using such high voltage capacitors in the pre-amp? Is this better, or doesn't matter till voltage is higher than nominal? Cause i can find much more polypropylene caps in high voltage rating than 63-100V. And is there something beneficial in using axial vs standart metalyzed ones? Also, i want to know if someone can tell me(@ramachandra maybe you know) the specs, model manufacture of the original ceramics, just in case if something go wrong with them (too many solder-desolder) The letters on them are 224Z LK, but can't find anything on the net about.
 
Cheers
 
Jun 7, 2014 at 7:36 PM Post #47 of 561
(jayjayuk) I see you found your project. 
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I suggest to not suffer with OpAmps unnecessarily, just do the Third Mod and you will save time and money. There is even a more simple way i have not mentioned in the thread, because i wanted to get the best result out of the system, not just do some upgrade. Basically the the C100, C200, C300, C400, C500 SMD components are 0.47uF ceramic capacitors, if you leave them untouched and just use a wire where i used the big 0.47uF axial capacitors you get the very same result, except the sound quality. Later you can upgrade further if you wish.
 
I know many people love the control pod. But, if you use a cable and connect the system directly to a good analog sound source and use 5pcs 22K resistors on the signal path for the surround instead ordinary carbon film pots, you make far the best Z5500. Require only 2 OpAmps!
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Bass redirect need to be turned on in the Creative software. If the bass is to much for the original sats, about 10uF NP caps in series should be enough to cut it back. Or other 2 way speakers capable to handle it will turn out perfect.
I have made a "Pod" from a project box and i have installed a LED, On/Off switch, Jack socket into. The switch serve as instant mute too, if something go wrong to set the proper volume in Windows. While the system sleeping the Jack socket is working for a headphone, when the system is on, the jack disconnected to be sure not interfere with the sound.
 
You are right, I have what you need. You can cover the sipping cost to your location, i need nothing else.  (details in private)
 
From 12 faulty boards i got 4 with problems related to those regs. Normally they are not running too hot, so maybe they have suffer damage or the short circuit ruined the capacitors belong to them and they struggle to maintain the proper voltage. All the 12 OpAmps hooked up on them so you can figure out what could happen if they fail and let the juice just go. Existing short circuit is also an option to consider.
 
(andro6600)  In the first time I have used cheap Pilkor MKT film capacitors in the Zobel network and the owner liked it. Usually the Wima MKS doing well for audio, look like this position is an exception. For my friends i have used Polystyrene capacitors (Excellent sound characteristic, out of production, difficult to source) and on the boards i had for sale  K73-11 160V and  MMWA 250V axial capacitors. To be clear i do not own the system, so my hearing not exactly up to the level after few weeks listening against who have the system for years, so i trust your judgment. The only thing is the sound is usually getting better after the a proper burn in period, so maaaybe there is a chance for improvement.
 
If you asking what i suggest to try, i recommend the 0.22uF K73-16 63V Soviet military film capacitors. They are almost as good as a piece of copper wire by listening and not generating noises according those who have done experiments with them and have the proper measuring equipment. You will find the Polyethylene terephthalate is not highly recommended for audio purpose, but i have to say the shape, construction and size of the caps just matter as much.
http://www.ebay.ie/itm/0-22uF-63V-PETP-Mylar-Capacitors-K73-16-Lot-of-4-/200902521600?pt=Vintage_Electronics_R2&hash=item2ec6b93300
 
I have found 3 different ceramic capacitors on the preamp boards this far. On the pre Pid 636 SMD ceramic, after that ceramic disk, on the latest series MP0/C0G. I have not dig deep into the word of the ceramics just experienced and told to avoid them for audio, so i have no more info on them I'm afraid.
 
Jun 8, 2014 at 3:21 PM Post #48 of 561
Ok guys, i just ordered the soviet military capacitors for pre-amp (@ramachandra thanks for advice) and we'll see how they perform. I just wondering something. The HPF in the amplifier is set too high, especially if you using better satellites, as i do, and they can not show full potential. So, you guys seems to know quite a lot about engineering, and since the HPF is combination of capacitor and resistor( and op-amp eventually) do you know where on the board is placed, and is there something that can be done to lower cut-off frequency to the satellites? I thing this is gonna be huge step up in the performance.
 
Jun 8, 2014 at 3:32 PM Post #49 of 561
@andro6600  i cannot help you with that... i am just a beginner who is modding stuff... but i have two of these boards so know my way around them quite well... more and more as i work with them.
 
i used some cheap caps from ebay and they was 630v and i knew i could fit them in so i bought them... i am trying to find some polystyrenes to go there but the cheapest i have found on ebay is £10 for 2 X 0.22uF polystyrene's from they 80's i think. i will keep looking for better ones but right now i am trying to get the main components in for the main and make some big upgrades all at once.
 
i will post some pics when i get some new stuff in... still looking pretty bare right now.
 
Cheers
 
EDIT:
@ramachandra i will keep that in mind about the smaller caps being 0.47uf... i will take that route on the second blown board before i put the r4580i's in it just to make sure everythings working before i put the op-amp's in... cheers for that... i have soldered wires on the pre-amp board bypassing the control pod (because i have been having problems with control pod... sorting that now) so i have heard the difference and i like the sound more when the control pod is out of the picture... that is why i want to mount on the back 3 X double rca's and a switch that will select between the control pod and direct input into the rca's i have mounted... i am half way through drawing up a design for the board that will do the switching and also switches to go 5.1 or mix into 4.1 quad using the front left and right for everything. you mentioned that you have made a pod for this system... basically that is what i will be making but integrating directly on the back off the plate amp (thats why i wanted a spare plate to drill and mash first) if you get time would it be possible for you to share some pictures of the pod you have made? would be interested in taking at look :)
 
Cheers
 
Jun 8, 2014 at 4:41 PM Post #50 of 561
As i read from private messages the mica sheets becoming problematic for many modder. When i have done the First mod i have learnt the hard way how messy can be, thanks to the thermal paste. I just turned the board to one side without cutting it off from the transformer and Subwoofer.
Later when i got a dozen i thought i have to do it somehow different. The wires was already cut of so i placed the boards to the bath and give them a wash with a paint brush and white spirit, than i sprayed them with multi purpose cleaner and washed them with water, than repeated the process few times. I left the boards to dry overnight on the radiator. The next step was to install terminal bars to the wires so it become easy to connect, disconnect from the rest of the subwoofer. The fragile mica insulators fall out of the options, so i used masking tape (made from paper) over the heat sinks and nothing else. The TDA Amps never had sort circuit or fried, still i do not recommend as a permanent solution because the paper deteriorate in time, and thermal transfer is not necessarily up to the level of the original. But do fine during the testings and until the new mica sheets arrive if some of them get damaged.
 
Jun 8, 2014 at 6:19 PM Post #51 of 561
my mica sheets are all splitting at the edges... they are fine for now tho... i will keep that in mind as right now i have the board in and out alot... i dont disconnect from transformer... i just put the sub on my bench and unscrew the amp and work on it like that... gets tricky putting the bottom screw and nut in to hold the circuit board though.
 
if the masking tape is made from paper then paper is an insulator of heat? just though i would ask
 
Cheers
 
Jun 8, 2014 at 6:39 PM Post #52 of 561
@andro6600 What you looking for is not on the amplifier board. It is in the pod and i do not know where to look. The whole pod is crowded with SMD, but as i remember the volume control chip can handle it alone so maybe not much can be done about it. With the Elnas the bass will improve on the sats. If you want some more get SB Titanium to mod, can turn out as good as the Z.
 
@jayjayuk I try to get some photos for you from the owner. I was abroad and i used what i could get from the the local store. Not pretty.
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  Working.....
 
The thickness of the masking tape is not enough to be concerned, at least not in the short therm. Paper is a good insulator of heat.
 
Jun 9, 2014 at 3:40 AM Post #53 of 561

 
@andro6600 What you looking for is not on the amplifier board. It is in the pod and i do not know where to look. The whole pod is crowded with SMD, but as i remember the volume control chip can handle it alone so maybe not much can be done about it. With the Elnas the bass will improve on the sats. If you want some more get SB Titanium to mod, can turn out as good as the Z.


@jayjayuk I try to get some photos for you from the owner. I was abroad and i used what i could get from the the local store. Not pretty.
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  Working.....



The thickness of the masking tape is not enough to be concerned, at least not in the short therm. Paper is a good insulator of heat.


I saw, that you replaced the caps around the control pod volume control, so is this worth spending money? If the HPF is in the volume control chip, what if it is replaced with something better? Where is that chip? I mean, how it looks like, so that i can track the part in the net. And about the 3 opamps in the pod, for analog output, do i have to change them if i am using just digital inputs? I don't want to spent money on a new Sound card, cause my PC is not the only playback device, and it is not reasonable for me. 


Man, i just can't wait for my Elnas to arrive! I am very curious what the sound they make! :smile:



Cheers

 
Jun 9, 2014 at 7:18 AM Post #54 of 561
@andro6600 so you have some elna's on the way... which caps did you buy? capacitance and voltage rating? and what did you end up paying? for 47uf 50v and 22uf 50v for the main amp 16 x of each it cost me £23.
 
@ramachandra please if you can... would like to see the pod. i was also thinking about putting 3.5mm jacks on the back aswell with a switch between rca and jack... im still unsure on my design right now... want it to be basic and simple with a few options and still have 5.1... i will quickly run out of room on the plate if im not careful :)
 
Jun 9, 2014 at 9:31 AM Post #55 of 561
  @andro6600 so you have some elna's on the way... which caps did you buy? capacitance and voltage rating? and what did you end up paying? for 47uf 50v and 22uf 50v for the main amp 16 x of each it cost me £23.
 
@ramachandra please if you can... would like to see the pod. i was also thinking about putting 3.5mm jacks on the back aswell with a switch between rca and jack... im still unsure on my design right now... want it to be basic and simple with a few options and still have 5.1... i will quickly run out of room on the plate if im not careful :)

I bought these http://www.ebay.com/itm/131189288110?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
and these for main filters http://www.ebay.com/itm/131189283371?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
I must say, they are quite expensive, but hope they worth it! I am going to try the combination with my Panasonics, and eventually buy Elna for the 22uF position.
 
Cheers
 
Jun 9, 2014 at 10:49 AM Post #56 of 561
just to make you aware if you are not already... those nichicon's are to big to slot straight into the board and you will have to modify it so that they do fit... solder wires to them on a standoff board or something like that.
 
these are the elnas that i bought...
 
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=360946019675
http://www.ebay.co.uk/itm/16-pcs-47uF-50V-ELNA-RFS-SILMIC-II-AUDIO-Capacitor-85-piNEU-Kondensator-Stuck-/360943345072?pt=LH_DefaultDomain_193&hash=item5409e65db0
 
came to £23 ... i will be buying filter caps or possibly caps all round for pod... have not decided yet... see how these 22uf & 47uf are on the op-amps and tda's
 
i did not want to mod the board like the op to get big caps in but i think i might and get some big elna for audio or elna for denon and like the OP use some more in parallel to the big ones. here are the caps i was looking at for direct replacements on the 10000uf and 4700uf...
 
http://www.ebay.co.uk/itm/Nichicon-KA-Audio-4700uF-25V-radial-105-capacitors-UKA1E472MHD-2pcs-/261479327054?pt=Componenti_elettronici_passivi&hash=item3ce161e54e
http://www.ebay.co.uk/itm/2-pcs-Japan-Nichicon-FW-10000UF-50V-Audio-Capacitor-for-audio-cap-/320852400459?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item4ab44b194b
 
Cheers
 
EDIT : 
Bargain = http://www.ebay.co.uk/itm/28PCS-22uF-50V-ELNA-SILMIC-II-RFS-for-HiFi-audio-silk-capacitors-Thailand-Made-/261287134910?_trksid=p2054897.l4275
 
Jun 9, 2014 at 11:41 AM Post #57 of 561
@jayjayuk, yes, i know that KG wont fit into the board, but planning to solder wires, as ramachandra did in one of his mod, and mount them to the subwoofer case. Hope this wont affect their performance, i don't wanna screw the board eventually. I considered Nichicon FW for direct replacement, but i know in audio the bigger- the better!  
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  Nevertheless FW will be superior to original ones, no dough! Wonder, is there any benefit with changing 4700uF pod capacitor?
 
EDIT
 
Look what is inside Sony Str-da5000es  
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Jun 9, 2014 at 4:12 PM Post #58 of 561
so i have been looking on ebay for polystyrene caps to fill the pre-amp board... there is 7 224's on there and 1 224 on the under side of the board... i found these on ebay... let me know what you both think... they will be a very tight squeeze to fit in... might have to go as far as putting the resistors on the under side of the board to off-set the caps...
 
@ramachandra i see you use the 0.47uf polypropylene of these for the op-amp by-pass... what do you think about the quality of these russian caps? would these polystyrenes be worth buying?
 
http://www.ebay.co.uk/itm/8x-0-22uF-250V-5-Hi-End-Polystyrene-capacitors-K71-4-/200960061884?pt=Vintage_Electronics_R2&hash=item2eca2731bc
 
@andro6600 i think the more i do to mine the more i will end up putting big caps in it aswell. i will more than likely build a board with caps in parallel like @ramachandra has done. 
 
Cheers
 
Jun 9, 2014 at 6:25 PM Post #59 of 561
(andro6600) This is the datasheet of the volume control chip: http://www.datasheet-pdf.com/datasheetdownload.php?id=508654 located near the pot right under the knob. I'm not saying upgrading the pod will be a dramatic improvement, for my hears the rest of the annoying noise and fog vanished, just the sound remain.
 
(jayjayuk) The Nichikon KW have the same size as FW and a bit more refined. I got the images about the "Pod" i made. First time i connected the Z5500 to the sound card without volume control and everything was great other them loudness. Dow on 10% was still unpleasant so i placed a cheap 50K 6 channel pot to the box, and the owner sad it is doing worst than the unmodified Pod. So i decided to buy 5pcs 22K 5W wirewound resistors and use them on the signal path instead, the Sub required none. So one switch turn the Sub on/off and a LED, switch the 2 front channels between the jack and the Z5500. I have used no jacks or RCA on the box to save money and have less unsoldered contact. On the end of the cables there is a D-sub connector and 3 jacks.
 

 

 
I have never tried those polystyrene capacitors, still i bet on that the western equivalent could cost a fortune. It is true about most of the Soviet military caps used for audio.  Maybe you should wait for andro6600's opinion on the K73-16 he bought.
 
Jun 10, 2014 at 1:36 AM Post #60 of 561
@jayjayuk wow! Those are some big boys! I think however, it'll be tricky to fit in.Otherwise, according to everyone, polystyrene should be ideal for audio.But then again, you have to try for yourself. Mine are on the way, and after couple of weeks, i'll share my thoughts about the sounding.
 
@ramachandra, thanks for the sheet, i will investigate the chip and the possibilities.
 

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