# Need help with pinout of Logitech Z506 DB9 connector

Oct 18, 2019
5
I bought a Logitech Z506 5.1 speaker system at a garage sale for $5. It was missing the Front Right (Control) Speaker and 1 Rear speaker but I want to try to hook it up to an HDTV as a 3.1 speaker system. The problem is I need to "bypass" the Control. What is the pinout of the DB9 connector on the subwoofer? I'm hoping I can switch the power by shorting 2 of the pins and control the volume with a potentiometer on the Left & Right channels. #### 73's de Edd Aug 21, 2015 3,365 Sir Lennie . . . . . You say . . . . . I bought a Logitech Z506 5.1 speaker system at a garage sale for$5.

SUCH a deal . . . already !

I would expect the DB connector to be routing 2 heavier wires as the speaker connections for that now wildly errant speaker.
Check out all of the other wires used on that DB connector and see if you can associate their terminations with the YELLOW
box markings that I have added on the schematic.
Volume is controlled within that IC electronically in internal gain / transconductance stages via that pot.

As far as the missing speaker connections I think that it will involve only one amp section of the left located STA540 Pwr amp.
I'm looking at the HEAVY poly caps associated with the crcuitry going into the right STA540 . . . . suggesting that whole / total unit
might be joined up in tanem . . . . JUST for driving the center woofer.

That leaves the left speaker being fed by one section of the many amps in the left STA540 . . . . . now CHE E E E E E ECK IT OUT .

MARKED UP TECHNO REFERENCING . . . .

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#### 73's de Edd

Aug 21, 2015
3,365
ERRATA . . . . caught after > 1 hr edit limitation. . . . . . on a reread.

Check out all of the other wires used on that DB connector and see if you can associate their terminations with the YELLOW
box markings that I have added on the schematic.

On that illustration, the bottom line of the YELLOW box, needs to be lifted up so that it passes between pins 14 and 15 of the I.C.

Text . . .

I'm looking at the HEAVY poly caps being associated with the circuitry going into the right STA540 . . . . suggesting that whole / total unit
might be joined up in tandem . . . . JUST for driving the center bass woofer.

Observation . . . .

Looks like a DB9 connector being used . . . . . on this product info photo and specs.

https://secure.logitech.com/en-us/product/surround-sound-speaker-z506

.

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#### Lennie

Oct 18, 2019
5
Thanks for the info I will try to reverse engineer the pinout of the DB9 connector on the Z506 subwoofer. If anyone actually owns the Right Front (control) speaker and could ohms check it for which pins are the power switch and which are the volume control knob & which are the Front Right speaker output that would be greatly appreciated.

#### Imhim

Jan 28, 2020
2
Did you ever figure out a way to use the subwoofer with the control speaker?

#### Imhim

Jan 28, 2020
2
Did you ever figure out a way to use the subwoofer without the control speaker?
Without the control speaker. I trying to do the same thing.

#### jeff15113

Jan 28, 2020
1
I found something that might be of help. Its the pinout of x230 FR speaker connecter. Its looks identical to the z506. Maybe the pinout is the same? I also have the sub without the control speaker. Looking forward to figuring this out.

#### Attachments

• Annotation 2020-01-28 051402.png
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#### Lennie

Oct 18, 2019
5
I found something that might be of help. Its the pinout of x230 FR speaker connecter. Its looks identical to the z506. Maybe the pinout is the same? I also have the sub without the control speaker. Looking forward to figuring this out.

No the connector is the same but the pinout is different. The Z506 has a single line volume control (e.g. just a pot for feedback). I haven't figured it out yet. If anyone has the control speaker and can trace the signals that would be a big help!

#### Gonzoid

Apr 1, 2020
1
No the connector is the same but the pinout is different. The Z506 has a single line volume control (e.g. just a pot for feedback). I haven't figured it out yet. If anyone has the control speaker and can trace the signals that would be a big help!
Not sure if you still needed this information.

Pin 1: Brown, Headphone jack ring terminal
Pin 2: Orange, On/Off button
Pin 3: Green, Going through a 10k resistor towards the headphone jack circuit, not sure what for
Pin 4: Purple, Headphone jack sleeve terminal and ground for potentiometer
Pin 5: Blue, Potentiometer
Pin 6: Red, Headphone jack tip terminal
Pin 7: Yellow, On/Off button
Pin 8: Grey, Speaker Negative (-)
Pin 9: White, tied to black wire, Speaker Positive (+)

Note that it's a dual pot on board. Tried to upload an image, but was unsuccessful. Hope this helps with your issue.

Unfortunately my issue is that the left/right speakers are now super quiet and have to be turned up all the way to hear anything, so I will have to troubleshoot that issue.

#### Lennie

Oct 18, 2019
5
Not sure if you still needed this information.

Pin 1: Brown, Headphone jack ring terminal
Pin 2: Orange, On/Off button
Pin 3: Green, Going through a 10k resistor towards the headphone jack circuit, not sure what for
Pin 4: Purple, Headphone jack sleeve terminal and ground for potentiometer
Pin 5: Blue, Potentiometer
Pin 6: Red, Headphone jack tip terminal
Pin 7: Yellow, On/Off button
Pin 8: Grey, Speaker Negative (-)
Pin 9: White, tied to black wire, Speaker Positive (+)

Note that it's a dual pot on board. Tried to upload an image, but was unsuccessful. Hope this helps with your issue.

Unfortunately my issue is that the left/right speakers are now super quiet and have to be turned up all the way to hear anything, so I will have to troubleshoot that issue.

Thanks for the info - my project is on hold at the moment but this information will definitely help me decipher the Z506.

#### Lennie

Oct 18, 2019
5
My project is currently on hold but this information will definitely help me decipher the Z506 speaker system. Thanks.

Apr 3, 2020
1
My project is currently on hold but this information will definitely help me decipher the Z506 speaker system. Thanks.
Please do post what you did as I happen to be in the same page got the speaker with the unit except for the front right anyway to by pass it would be a great help. Anyways with my limited knowledge of electronics I tried shorting the pins 2,7 and 4,5 to get the speakers to work but in vain. Now I don't know if they are out of order or is there something else to do any advice would be appreciated.
Regards.

#### avramar64

May 23, 2020
1
Hello everyone!

1 - audio signal to headphones connector (R)
2 - Vcc after power switch ON
3 - connected through 10k resistor to pin 2 of DB9 for normal operation. Disconnected for headphones use.
4 - GND
5 - Potentiometer cursor
6 - audio signal to headphones connector (L)
7 - 20 Vcc from power supply
8 - FR speaker +
9 - FR speaker -

The potentiometer resistor is connected to GND through a 1.2K resistor and to Vcc through 560 ohms resistor. The cursor goes to pin 5 of DB9.

Potentiometer value is 50K

An approximate schematic is attached.

#### Attachments

• Z506 FR.png
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#### Falken

Dec 26, 2020
2
Hello!!

Some picture bro? Finished conections? Step by step please.

I neee help too.

Thanks.

#### Falken

Dec 26, 2020
2
Hello everyone!

1 - audio signal to headphones connector (R)
2 - Vcc after power switch ON
3 - connected through 10k resistor to pin 2 of DB9 for normal operation. Disconnected for headphones use.
4 - GND
5 - Potentiometer cursor
6 - audio signal to headphones connector (L)
7 - 20 Vcc from power supply
8 - FR speaker +
9 - FR speaker -

The potentiometer resistor is connected to GND through a 1.2K resistor and to Vcc through 560 ohms resistor. The cursor goes to pin 5 of DB9.

Potentiometer value is 50K

An approximate schematic is attached.

#### rodi_s

Dec 13, 2021
1
Not sure if you still needed this information.

Pin 1: Brown, Headphone jack ring terminal
Pin 2: Orange, On/Off button
Pin 3: Green, Going through a 10k resistor towards the headphone jack circuit, not sure what for
Pin 4: Purple, Headphone jack sleeve terminal and ground for potentiometer
Pin 5: Blue, Potentiometer
Pin 6: Red, Headphone jack tip terminal
Pin 7: Yellow, On/Off button
Pin 8: Grey, Speaker Negative (-)
Pin 9: White, tied to black wire, Speaker Positive (+)

Note that it's a dual pot on board. Tried to upload an image, but was unsuccessful. Hope this helps with your issue.

Unfortunately my issue is that the left/right speakers are now super quiet and have to be turned up all the way to hear anything, so I will have to troubleshoot that issue.
Thanks for this information. I was looking for this as well!