Hacking the Logitech Z5500

and by the way, i connect my input like this:

95548d1250561267t-hacking-logitech-z5500-z5500_inboard_top.jpg


have something changed?
i changed my HCT139 too, first i thought that this part is damaged, but it wasnt the foult, i changed the Diode and it wasnt working too, then i changed the resitor at the power supply ant it runs again, but the 2 Channels stress me!
 
hi all.
now i finished my project!
it work now!
first my transistor for +18V was damaged. i fixef it then
my rear and center speaker was very very quiet and sometimes all speakers become noise and sound like a wind in background ( hope u know what i mean)
i look for the voltage on the small IC on every channel and i sas that on the damaged channels the voltage is not 16.50. they where about 15V
the resistor 100 Ohm close to the ELCO 47uF where damaged and little bit black. and now Ohm anymore. i fixed it and the IC got only 6.50V and become really hot!
i put the resistora away and switch off the power supply from the IC and bridge it like the picture!
the channel sounds loud like every other (maybe a little bit louder i think)
iam very happy now!

Greeting Lucas

An externally hosted image should be here but it was not working when we last tested it.
 
hey guys, i have a set of z5500 and my control pod is working just fine. the problem is that i want to connect my sub with my Onkyo receiver

I have taken an RCA from the onkyo sub exit, and using a 3.5mm adapter i have connected it to the Center/Sub input in the control pod. then using the Analogue input at 6.1 i can get some "sound" to the sub, but it is not loud at all.

so i was thinking that it probably is my pod's fault. I was thinking of buying this cable

Logitech Z-5500 Control Pod Bypass Subwoofer Cable 5.1 | eBay

maybe this will make the sub to work properly with my onkyo?
 
Good Evening,

1.) Mis, can u show me some pictures of your Z5500 RCA? my was an RCA too and now it works!

2.) Does somebody know how i connect an
Potentiometer to change Volume, cause now its very loud and i change it with my Computer.
Ive read something, now i got 5V on this pin, when i put an Potentiometer in, is it possible to set the Voltage to 2V that its more quiet?

Greets Mordi

 
Here is outside picture of my RCA
My PID number is 441R.
On the second page forum member undertone worked, even a fairly well explained,but without pictures.
But I see that last couple months and member KILLER_K is looking for a little bit more information,
which was by the way ignited the regulator.
So I'm afraid that something goes wrong.
 

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But I see that last couple months and member KILLER_K is looking for a little bit more information,
which was by the way ignited the regulator.
So I'm afraid that something goes wrong.


Hi,
I'm currently still looking for some more regulators. As everywhere I have found makes you buy a large amount. Or either charges you like $30 bucks to ship them out to you. I was just going to buy about 12 or so in case anyone else needed some. As you shouldn't have to go through that much stress to get some parts shipped to you. Thanks
 
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Hello,

I have a busted Z-5450 system, and I was hoping to use the subwoofer into a Yamaha receiver with a Sub out.

In the past, I had used the L/C/R speakers by just putting the wires into the back of a stereo, I also clipped the red/black wires coming out of the subwoofer and put them directly into a stereo (I guess this meant it was being used as a passive sub). I recently got a new receiver with a single Sub out, and I am hoping to connect this somehow from the amp.

I have also seen an option of buying a Lepai Hifi Stereo Amp (20 Watts), but I'd rather try to use what I have, since I have a soldering iron and wires.

Thanks in advance for any advice you can lend me.
 
Logitech Z-680

Hello

I didn't find much information on the Z-680 so I did some reverse engineering on my own.

Here's the female DB15 pin-out with the corresponding marking inside the pod:
Code:
1   Center
2   FR
3   FL
4   RR
5   S (Sub)
6   G
7   SB (Stand-By, needs +5 volt to enable)
8   UNUSED
9   RL
10  +8
11  G
12  G
13  UNUSED
14  +18
15  -18
Pic of the markings inside the pod:
DSC_0499.JPG

I recently bought a Yamaha receiver and wanted to use it with my Z-680 sub, so I made this from some parts that I had (VGA extender cable, RCA-switch and a LM7805 +5v voltage regulator). The Yamaha has a trigger output that puts out 12v when it turns on, so I use the voltage regulator to take it down to 5v. But if you wanted to, you could use the voltage regulator on the +8 instead and have it always on or use a switch.

DSC_0492.JPG
DSC_0495.JPG

Thanks,
And I'm out!
 
Amazing info

Hey guys,

Thanks for all the great info posted here, incredibly helpful.

My experiences in summarized point form:


  1. 1. Have had z5500 spring clip version for about 5 years no issues (I love these things)
  2. Pod was intermittently switching itself to standby once a day
  3. After about a week of this, the pod switched off completely (no standby light)
  4. Searched for fried components, found a resistor next to one of the chips that was black with some surrounding blackness, figured was culprit, but tested it with multimeter and seemed to be working correctly.
  5. I was ready to build a bypass as described here, mapped out all my pins to hotwire tomorrow, after discovering where the sub goes I walked away and came back to the standby light on all by itself ?
  6. Put back together and everything worked again perfectly?!?!?


I have no idea what fixed it, could have been just wiggling it around, could have been joining the 16v pin to random input pins (risky, but I didnt care as I was about to bypass it)


I couldn't find a complete z5500 spring clamp pin guide so here is the summary I made:


First column is order on PCB from left to right on wire side
Second column is the pin number on the socket (most referred to here)


1 - 8 yellow - Power on amp
2 - 7 blue - Power on amp with center muted
3 - 12 purp - ?
4 - 11 green - ?
5 - 10 red - ?
6 - 5 yellow - left front in
7 - 9 purp - right front in
8 - 4 blue - center in
9 - 3 yellow - rear left
10 - 1 brown - rear right
11 - 2 gray - sub in (+5 volts)
12 - 14 red +16
13 - 15 black -16
14 - 13 green - ground


On my version pin 6 was not connected to anything.

An interesting fact:

Connecting PCB pins 1 and 5 (socket pins 8-10) caused my pod to power up, standby light turned on, power button worked, but screen would say
Effect: Detecting...
Then switch back to standby, thought this info might help someone with more electronics knowledge deduct what the problem is in the first place.

I was speaking to an experienced sound engineer about the sub pin placement, and he found it odd that there is 5v coming from the amp and sub signal is sent back on the same wire. Obviously as an internal circuit Logitech can do what they please, but many people here are wiring this directly into an input cable. He raised a concern that this may damage driver devices as they don't expect voltage to be coming into their output jack (like Phantom power that fried his iPad).

Anyway, cheers for the helpful resource. My z5500s are back to full operation, hopefully will get another 5 years out of them :)
 
You probably have pre636 PID

I have dug into this making my own bypass cable and yes, pin 6 has no connection. I have found that applying the 8v+ through a resistor to pin 7 turns on the amp with no center channel. After VOM'ing out the pins on the control pod that works for a short time, 8 is grounded until you mute the system them it goes to +3.7v. Keep in mind it is sounding like the activate voltage on these models PRE636 and greater then 200 have a + trigger state. 3.5v is what is expected to trigger the amp, either on or mute, Else should be grounded.

Only pin I have no explanation for is the pin 12 on the db15 has a low ref voltage but no idea how its used. Based on what we are hearing you can not activate the center channel on this model without internal mods on the actual sub. If you do this you want to make sure pin 7, 8 grounded. this post has great pictures. Of course I will modify this slightly and have 2 100 ohm resistors tied to the 8v spot and the other end of each feeding each of the trigger points to keep them both at around 5v.

Also remember you may want a 45k ohm pot in line with the sub input to control the sub volume. I am actually thinking about putting these pots on every input so I can have my computer at half without blowing out the speakers. Right now even 5 is pretty loud.

An alternative if you are not building your own cables is the bypass cables listed on ebay. Recommend the post636 when doing the internal sub mod if you want center to work. These cables have the 6,7,8,13 grounded.

The pre636 cables tell you they will not enable center channel without having a mod. These cables will apply the +5v at 7 also.
 
My success was short lived (as expected), back to dead again, but this time the amp switches itself on when it gets any power. This is different from anything I have seen before, this morning entire pod was working, powered on and off fine, now amp is always on, can get sound through it without even putting voltage through the amp turn on pins.

Starting to suspect the logic circuts in the woofer box are problematic. Anyone got any ideas?
 
Mine does the same thing and it is the POD

Mine powers on, detects, and may play for a while but then no sound. sometimes it comes on and does nothing. I have been working on rewiring mine not using the POD and it all has worked except center channel. I finished last night the internal mods to the sub for pre 636 pid's. The difference was that I supplied 3.5+v to both orange and white instead of the 8 and 3.5v and it still didnt activate the center channel. Both were fed through different resisors. Tonite will be trying some a bit different.

FYI when pod is working, I have measure the voltages at orange and white inside the sub. This is 5.6v or so on both.
 
Answer on the pre-636 wiring.

Not sure if this accounts for all of them but you can get it to work without any internal mods.

When I opened mine up I looked at how the hardwiring trick for the orange and white wires was working and noticed the reason they had to insert the resistor between the orange and white wire was because it somewhat isolated the Resitor / Capacitor loops on the other end of each of these circuit in effect allowing it to work. So I went further back into the circuitry and diagnosed how to get this to work on a unit with only the pin 7 and pin 8 configuration to the HTC139 chip.

Data Sheet for the HCT139

I noticed that pin 8 is wired to a0 and 7 to pin a1. It drives the 1y0-1y3 high lows depending on the combination of voltage(high / low) applied to the a0/a1.

Looking at the circuitry the white wire(all but center) is driven off of two diodes one is connected to 1y2 and the other to 1y3 which means if either of these are high then the main speakers are enabled(not center). The 1y1 is attached to a npn transistor which enables a high on the orange wire enabling the center speaker. To drive the output to a high state on the output of the transistor requires a low on the 1y1 output. So by looking at this you can essentially leave pin 7 to ground as it still has one or the other outputs high and the pin 8 can be supplied a high voltage to the pin.

What I did is took and grounded the pin 7 and took a 220 ohm resistor between the +8 v pin and the pin 8 to properly enabled all the speakers. No longer needing the internal modifications and the circuits stay isolated due to the diodes/transistors properly applying the enabling voltage to the orange and white wires.

Only other thing I did is put volume control into the input circuit by adding 47k ohm pots in line.

If hooking pots up make sure you hook them up like this:

Input >>>>> ------ pin1 pin2 pin3 -----<<<<<< Shield/Ground
|
|
|
|
output to speakers

You will most likely for sure need this for the sub. I did it because I could only bring my computer volume to 10 before being to loud. By adding these inline on all inputs I have my volume at about 50% and its about right and allows me to also turn it up loud if I want(75%)