Logitech Z-5500 recap and speaker connection mod.

[rgsgww]

I'm recapping my logitech z-5500 because 1-I'm a hacker who likes to hack stuff to peak potential and 2-Because it is filled with crappy su'scon capacitors (I would expect such capacitors in a cheap system).

The speaker connection broke on me (12 awg solid did it...) so I'm just going to solder leads out of the board.

This thread is going to list my progress on the mod. It may have a few questions along the way.

Anyways, I'm lost at finding the right ceramic disk caps and polymer.

There are no voltage labels or uf, just a few numbers. Is there a way of determining values based on those numbers? I think I remember using those, but it has been a long time since I was messing around with capacitors.

[rgsgww]

Some pics

Speaker connectors...


Speaker pins


12 awg power cord with ground installed, removed metal oxide varistors so its a little messier.


Subwoofer caps


Subwoofer caps and the boards power capacitor


Eww...goey thermal paste with insulators for the mosfets


Poly caps


Ceramic disk

[Toasty]

Re: Logitech Z-5500 recap and speaker connection mod.

>>Anyways, I'm lost at finding the right ceramic disk caps and polymer.<<
From what you're showing, why would you want to replace those caps?

I'd stick with the recapping of the electrolytics with some high quality, low ESR caps.

Little to be gained (if any) by replacing the ceramic or polystyrene caps. Don't confuse the term poly (used loosely in the forums for polymer) with those caps. Different animal.

Those speaker connectors are not really meant for solid wire. Stranded is recommended.

Toast

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

From what you're showing, why would you want to replace those caps?

I never liked su'scon caps, I also want to use a better quality, low esr cap.

Little to be gained (if any) by replacing the ceramic or polystyrene caps. Don't confuse the term poly (used loosely in the forums for polymer) with those caps. Different animal.

Really? Alright, I will not redo those. I kind of realized that while looking at different caps.

Those speaker connectors are not really meant for solid wire. Stranded is recommended.

Yeah, thats what I thought. I had all of this 12/2 romex around and it really did sound good.

[Toasty]

Re: Logitech Z-5500 recap and speaker connection mod.

>>I never liked su'scon caps, I also want to use a better quality, low esr cap.<<

Nope. You missed that I quoted you saying -
>>Anyways, I'm lost at finding the right ceramic disk caps and polymer.<<
and my response was -
"From what you're showing, why would you want to replace those caps?"

You came to the right answer however -
>>Really? Alright, I will not redo those... <<

Up the wire gauge from factory to the sub and woofers. 14 stranded is good and tin the ends if you use the factory connector.

Mids, rears, & tweeters are fine on factory wire.

IMHO don't go crazy on upgrading this. It's a $200 system, not $20,000, deal with it.

It's the old adage about making silk purses out of sows ears. Just can't be done. You're going to beef up the caps and that's good. Heavier wire to those speakers is good. Anything else is fluff and no one will hear the difference.

Toast

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

>>I never liked su'scon caps, I also want to use a better quality, low esr cap.<<

Nope. You missed that I quoted you saying -
>>Anyways, I'm lost at finding the right ceramic disk caps and polymer.<<
and my response was -
"From what you're showing, why would you want to replace those caps?"

You came to the right answer however -
>>Really? Alright, I will not redo those... <<

Up the wire gauge from factory to the sub and woofers. 14 stranded is good and tin the ends if you use the factory connector.

Mids, rears, & tweeters are fine on factory wire.

IMHO don't go crazy on upgrading this. It's a $200 system, not $20,000, deal with it.

It's the old adage about making silk purses out of sows ears. Just can't be done. You're going to beef up the caps and that's good. Heavier wire to those speakers is good. Anything else is fluff and no one will hear the difference.

Toast

Yeah, It is a $200 system, I don't think any miracles are going to happen, I just like to hack things to make them better. I oc my computer, etc.

I did upgrade to 18 stranded (previous was 22)

I suppose I will pull the sub out and resolder some 14 stranded.

I was thinking of replacing the polymers and ceramics, but you changed my mind.

Those black wires on the picture that shows the polymers are sort of "interconects" They are 22 awg aluminum. Do you think I should upgrade to thicker copper? I have plenty wire laying around.

Since I have the wire around....should I use copper twisted pair for the aluminum wires connecting the amp board to the speaker connectors?

[Toasty]

Re: Logitech Z-5500 recap and speaker connection mod.

It's not aluminum wire. It's plated copper and it's okay.

Up the gauge if possible on the interconnect to sub & bass. Rest are fine.

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

I found an awesome distributor of caps, etc.

http://www.mouser.com/

Do you think I should replace the caps in the controller that decodes the optical signals, controls volume, etc. Or is the amplifier part the most important?

I'm going to keep the copper clad.

Digi key said that it might take until may 25 for most of my caps to be available.

I'm going to go dissemble my modem and go look for bad caps in there. I read a thread about a guy who did that and got some more packets.

[Toasty]

Re: Logitech Z-5500 recap and speaker connection mod.



Search for Mouser on the forums...

Stay in the amp & power supply.

Who's caps and what series' are you using for what?

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

Nichicon audio caps, check my cart out.

https://www.mouser.com/ProjectManage...sID=2eb1ba4d6a

Yeah, I am surely a capacitor noob. I am very knowledgeable in higher voltages-power distribution, etc.

[Toasty]

Re: Logitech Z-5500 recap and speaker connection mod.

Hold on to that order for a bit. I'm on my way out and I'll go over it better later.

Which ones are you replacing in the power supply section?

Which ones are REALLY being used as audio caps?

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

Hold on to that order for a bit. I'm on my way out and I'll go over it better later.

Which ones are you replacing in the power supply section?

Which ones are REALLY being used as audio caps?

Ok.

Upon removal of the large 10000uf caps I was able to identify 2 more caps, which are 47uf 50v. Unlike the majority 35v. This is the replacement cap I'm looking at. 47uf 50v

Here the board's power regulation area. (little big, ask if you want it a little smaller.....)

http://i428.photobucket.com/albums/q...w/100_5494.jpg


Should I be using different caps for the power regulation? Not audio caps?

[Toasty]

Re: Logitech Z-5500 recap and speaker connection mod.

Definitely not audio caps for power supply. Power supply and associated caps providing juice to the amps etc should be as low an ESR as you can get/fit in their.

The problem is I don't know what caps you've pulled from where. Which ones came from the audio sections? It really isn't necessary to deal with all the little ones. The amp outputs and power inputs are good enough plus those in the power supply. With a few exceptions, only those of 330uF and up in the power supply.

The point you're missing here, and the real reason of doing this kind of "upgrade" is to improve what you remove. Just replacing the caps with a better brand is not the correct way, and doesn't imply they are really any "better" at their job. Upgrading to a better cap in the power supply does not mean that the same value cap will work correctly in the audio area.

You have to take the time and lookup the spec's for what you are removing in that manufacturer's datasheets. Then look at what the suppliers have available in that grade or better and by what manufacturer.

It's not a wham-bam-thank-you-ma'am type of job. It takes a bit of time, some research, patience, and some headaches. You're gonna go into information overload at some point.

You can learn a great deal from some of the DIY audio forums out there. See what they're using to up their systems and amps.

Toast (is tired) lol

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

It looks as if the rest of the caps are from the audio section. I will try to look around, maybe I can find some logitech datasheets, etc so I can get a better idea of the board layout.

[Toasty]

Re: Logitech Z-5500 recap and speaker connection mod.

No, no. Datasheets for the caps not the system.

Here: http://www.su-scon.com.tw/

Look under products tab for your type (radial leaded OR snap in) and series. Then get the PDF and find the specs for your caps. Easier to print PDF and read it.

Post back what you find.

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

Yeah, I know to do the caps aswell. Was in a hurry typing.



Looks like all of the caps are sl series.

[Logistics]

Re: Logitech Z-5500 recap and speaker connection mod.

Which IC's* does this amplifier use? Can you see the numbers?

*Integrated Circuits (the chips that actually are the amplifier)

[rgsgww]

Re: Logitech Z-5500 recap and speaker connection mod.

Mosfets... what ic do you want to know?


A few small ics say this

r4580I
75khov5g4

Mosfets are TDA7294 by STmicroelectronics

I did a little cap replacement on my router (should have done the whole darn thing!) and my speeds are a little better.

[hardwareguy]

Re: Logitech Z-5500 recap and speaker connection mod.

TDA7294 is not a MOSFET.....its an amplifier on a chip. It uses a MOS output stage internally and can put out a maximum of 100W. Expect 50W continuous when not bridged.

[Logistics]

Re: Logitech Z-5500 recap and speaker connection mod.

I wonder what that 4700uF is all about. I'm getting the impression they're using it as the bootstrap cap (C5 in the datasheet) or it is instead an output decoupling cap that they're using to bump up the low-frequency output.

The one reason I could see for changing some of the ceramics is if they are being used at either pins 2 or 3, which are inputs. These should be non-polarized, which ceramics are, but ceramics are one of the worst things to pass an audio signal through, and in an ideal situation would be changed to films if space allows, bipolar electrolytics if space does not allow. If they are electrolytics, and space just does not allow for films then they should at least be changed to non-polarized electrolytics. I have never seen a line-level signal that was higher than 4V so you could use a 6V non-polarized (bipolar) capacitor, here. Although, if the values match those in the datasheet you would have to use at least a 10V to get that 22uF at pin 2 in a Panasonic SU from Digi-Key and a 50V for the 0.47uF at pin 3, both of which are 5mm in diameter and 11mm in height.