Hacking the Logitech Z5500

Hi all,

I have the spring-clip z5500 subwoofer, also a leftover from Logitech's mind-baffling way of doing business. It must b expensive to ship an entire system including subwoofer every time there's something wrong with the product. We just had problems with bad satellite speakers, go figure...

Anyway, I'd like to use it with a standard amplifier/receiver (Kenwood VR-209) that has an RCA out female jack for a powered subwoofer.

I'm no electronics genius. I can follow this thread (with some effort) but being a lazy bum am hoping there is a simple answer to my question:

Without even opening up the unit, can I just chop off one end of an RCA cable and strip the wires, then connect pin 2 on the DB15 to the
"male" wire of the RCA cable, and pin 13 to the "sleeve" wire (or whatever you really call these)?

I understand from the previous posts that I might get more bass than I want, but am I headed in the right direction, or is it more complicated than this?

(If some of the other DB15 pins are providing voltage out, maybe I could just cover them with electrical tape or put on some shrink-plastic sleeves?)

Thanks!

Mark

DB15 connector:
2 - Sub In
13 - ground
 
baumm said:
Hi all,

I have the spring-clip z5500 subwoofer, also a leftover from Logitech's mind-baffling way of doing business
...
Anyway, I'd like to use it with a standard amplifier/receiver (Kenwood VR-209) that has an RCA out female jack for a powered subwoofer.
...
Without even opening up the unit, can I just chop off one end of an...
...
(If some of the other DB15 pins are providing voltage out, maybe I could just cover them with electrical tape or put on some shrink-plastic sleeves?)

Hi you lazy baumm :D (sorry couldn't resist...),

The audio in is fine but you still need to turn on the amplifiers which are otherwise off. lakata reported that grounding pins 6,7, and 8 turned on the amp, and that's on the spring-loaded connectors version (yours).

So if you do both those things, you should be in business. Just make sure to use a well shielded (metal body) DB15 and a well shielded audio cable because it's a high-impedance line (like an electric guitar) and very susceptible to noise pickup. You might also want to keep the line as short as possible for the same reason. I would connect the other 5 input pins to ground so they don't stay floating. All the other unused pins can just be left unconnected, just make sure they don't touch each other or other pins.

BTW, I had to increase the passive attenuation to 1/2 on mine cause it was still too loud. Check if your receiver has a greater than 10 dB attenuation range, otherwise I'm pretty sure you'll have to include one as well. If you do build an attenuator, make it in a metal shell.

Steve
 
OK, I'd rather look dumb than make a big mistake and fry something:

The JPG posted by undertone (which I realize is for the RCA version, and I have the spring-clip) describes the pinouts as "rear view of female 25-pin plug". Is this what you see on the outside of the RCA sub?

My spring-clip unit has a 15-pin male connection on the outside of the sub. Should I associate lakata's description of each pinout with the pins as I see them (top-to-bottom, left-to-right) or do I need to reverse them left-to-right to match a female connection?

Here's the ugly diagram I made in Word as a copy of undertone's JPG, but with most of the spring-clip info from lakata. Is it correct, or backwards?

Thanks!

Mark
 

Attachments

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Hey sorry man, I haven't been checking this thread for a few days...

baumm said:
OK, I'd rather look dumb than make a big mistake and fry something:

Always a wise policy :)

baumm said:
The JPG posted by undertone (which I realize is for the RCA version, and I have the spring-clip) describes the pinouts as "rear view of female 25-pin plug". Is this what you see on the outside of the RCA sub?

Yes: the pinout of the male DB15 on the sub and the back of a female DB-15 plugged into it will obviously be the same. And I mistakenly called it a "DB-25"; it's clearly a DB-15, but I'd already posted it by the time I realized that...

baumm said:
My spring-clip unit has a 15-pin male connection on the outside of the sub. Should I associate lakata's description of each pinout with the pins as I see them (top-to-bottom, left-to-right) or do I need to reverse them left-to-right to match a female connection?

The pin numbering is standard and aligned with the trapezoidal shape of the plug. Most DB-15 connectors have reference numbers embossed on the outside of the pin hole rows on your female jack. Your diagram looks correct and matches the descriptions provided by lakata and Bob. If you have a VOM you can quickly check the voltage between pin 15 (-18v) and ground to check the orientation. I find it weird that ground is on different pins on the two models.

Let us know how it works out!
 
Hey, thanks for your patience -- my problem was that I didn't know what a pin-out is, so I wasn't sure if it was on the inside or the outside. Now I've got it.

I'm going to post the colors from my S-VGA cable (15-pin, missing one pin) just in case they are standard. Probably I'm wrong about that, but what the hey:

My S-VGA cable had three thick wires and eleven thin ones.

1 - Thick red center
*2 - Thick green center
3 - Thick blue center
4 - Thin black
5 - Thin brown

~6 - Thick red sleeve (if that 's the right word)
~7 - Thick green sleeve
~8 - Thick blue sleeve
9 - (missing)
10 - Thin red

11 - Thin orange
12 - Thin yellow
~13 - Thin green
14 - Thin blue
15 - Thin purple

To get the sub working, I did exactly as undertone recommended:

A) Soldered the center wire from my RCA plug to #2.

B) Soldered the sleeve wires from my RCA plug to #6, #7, #8, and #13.

The thump when I turn on the sub is pretty minor -- maybe because pin 8 is enabled?

The bass signal isn't impossibly loud either (though it's loud). Depending on the CD, I'm taking it down 2-10 decibels.

Cheers!

Mark
 
Hello. I've got a set (with springs) with a pod, but the cable had been cut off.
Is there a way to wire pod to the sub? There are connections WA14, WA13, WA12, WA11, WA10, WA4, WA5, WA6, WA7, WA8, WA9, WA1, WA3, WA17 on the pod's board , but I don't know which pins they shoud be wired to.
 
hi baumm,

i have a sort of similar problem, my Z5500 isn't working properly (when i do the test tone, the right rear speaker doesn't have any sound, and when the left rear speaker plays the test tone, so does the right rear, it seems the rear speakers are in 'mono' not stereo). I was thinking of doing the same thing you did (connect it to an AV Receiver), can you post some pics of what you did? your last post explains in detail what you did and is a big help, i just have to get the guts to do this mod on my Z5500!
 
controller pod as preamp

I'm curious if the DD/DTS and preamp functions on the z-5500 are handled by chips/PCB inside the controller pod. When I reconfigure my office space, I'm considering dismantling the Z-5500, but I'd like to keep the controller. Would it be feasible to use a separate power supply and use the controller as an "independent" preamp?

If possible, I'd use the existing D-sub connector and make a new enclosure with RCA outputs for the 5.1 connections with a separate amp.

Squib
 
Re: controller pod as preamp

squib said:
I'm curious if the DD/DTS and preamp functions on the z-5500 are handled by chips/PCB inside the controller pod. When I reconfigure my office space, I'm considering dismantling the Z-5500, but I'd like to keep the controller. Would it be feasible to use a separate power supply and use the controller as an "independent" preamp?

If possible, I'd use the existing D-sub connector and make a new enclosure with RCA outputs for the 5.1 connections with a separate amp.

Squib

Hi Squib,

ALL of the coding/decoding, matrixing and volume control is done in the pod. The Subwoofer is basically amplifiers and power supply.

But what you want to do with the pod might be a challenge. We've managed to make the amps work by poking around and tracing the relatively simple circuits in the speaker while the pod is a much more complicated circuit (and don't forget that there's 2 different types of amplifier topologies, so there might be differences in their respective pods as well). But if you do go that route, let us know how it works out.

If you're got a complete working system and you're going to dump the speakers, IMHO you'd be better off selling the kit and buying a 5.1/7.1 integrated receiver. There's many decent relatively inexpensive ones with Dolby/DTS.

u
 
Thanks for the reply and info, undertone. I know that purchasing a working 5.1/7.1 receiver would be the straight forward approach, but I was curious to see if I might be able to re-use what I have on hand. I like the controller for the z-5500 just fine, so re-purposing the pod as pre-amp seemed a possibility. I'll be moving my "surround system" (err, z-5500) from a small room (12 x 10 ft) to a larger space (~16 x 20 ft) and the z-5500 is obviously not going to cut it. This wont be happening for some months, so I have time to evaluate all the options.

I was HOPING that the db-15 plug on the umbilical cord would have a fairly obvious option for connecting RF, LF, C RR, LR, and SUB line-level outputs plus a 12v(?) input.

Squib
 
Hi, I've been reading this thread for over 2 weeks, I've tried everything possible, and yet I still cannot figure out how to make my z5500 turn on. I tried the enable in's to 5+, and to the ground.. nothing worked..

I have the spring loaded one, and I am pretty handy with soldering and a dvm.. anyways, I was wondering if anybody had any info for me, This thread is pretty old, but its the only one of its kind for the z5500 and what we want to use it for !
 
Hi,

I'm completly new here and just found this google'ing for the pinout of the DB15 connector on the Z5500 set.

Well here is my thought, I have this complete z5500 set that has a dead control center. It is not possible to get a new one from logitech since I live on a remote Island and the waranty is out, plus I got it for free since it was already broken.

Now I would love to hook this baby up to a AV Reciver. It would be fairly straight forward to connect the speakers directly to the speakers output of my reciever and use pin 2 and ground for the pre amp subwoofer output. But it would be pretty sweet to be able to use the built in amp for all the speakers but not only the sub. That would require an pre amp output from my reciever, that I don't have.

My question is simply do you know of any "not-so-expencive" AV Preamp recivers, like this one http://www.outlawaudio.com//products/970.html . but maybe few hundred dollars less expencive.

Regards
Oskar
 
This is sweet.

I built a small box with RCA inputs in one end, SUBWOOFER pot to controll the LFE input and a short cable with metalshielded HD15 in the other end.

Hooking this up to a decoder or a multichannel-out enabled DVD (with volume control, ofcourse) worked like a charm on all channels.

My problem is that the SUB input is too low. That particular input seem to be connected to GND through a 10kOhm resistance somewhere, which could explain the lesser gain. Could this be due to the LP filter it runs through?

It has loads of gain if I connect a normal linelevel signal, like the FRONT L or R, or a CD player directly, but a conventional SUB PRE-OUT on my DENON A/V Receiver gives a very low signal. I have to let it pass unattenuated with 12dB gain set on the SW output on the receiver to get good bass.

So, my question is, do the SW input line have some built in attenuation? If so, is it disconnectable? And if it's the filter, I really don't need it since my A/V have built-in LP filter on the SW PRE-OUT, so could someone give a hint on where the filter is situated in the sub, so I could bypass it?

Thanks for any help.

//
SONiQ
 
Hello people,

I find this thread very interesting, because I'm trying to get a Z-5450 running that I bought cheap. Unfortunately the pod doesn't have a connector any more.

Now I'm tying to get it to work. So far the pin layout seems to be very similar to the Z-5500's one. The amp turns on and I've got the satellite speakers running, but the subwoofer is very, very, VERY quiet. Maybe it's even muted, I don't know. :/

At the moment I have it connected like this (for subwoofer only):
pin 2 <--- line out (for subwoofer)
pin 6 & 7 <--- GND from line out (turns amp on)
pin 13 <--- GND from line out


It would be very nice if somebody could help me. Do you know what pins do I use to power the pod (thick red and green line?)? Or does anybody have an idea how to get the subwoofer loud or unmuted?

Your help is very appreciated, thank you! :)
 
z5500 it just doesn't fire up!

liv2ride said:
Hi, I've been reading this thread for over 2 weeks, I've tried everything possible, and yet I still cannot figure out how to make my z5500 turn on. I tried the enable in's to 5+, and to the ground.. nothing worked..

I have the spring loaded one, and I am pretty handy with soldering and a dvm.. anyways, I was wondering if anybody had any info for me, This thread is pretty old, but its the only one of its kind for the z5500 and what we want to use it for !

I've got the exact same issue. Just can't get it to turn on. I've got about 15cm (~6") db15 cable in the end of the sub, i have wired all the input pins to headphone connectors +wire and pins 6,7 & 8 to ground (tried +5v also). The connections should be right... There's just this little *snap* from the woofer when i connect pins 6,7 & 8 to ground.

Have i misunderstood something here or is the amplifier really broken?
This is the only forum i managed to "google" considering my issue.