Logitech Z 2300 Controller

I apologise for resurrecting such an old thread. I've built a controller to the same specs as what HxCxK has on that circuit diagram, however I'm running into a few issues.

Bass control doesn't seem to be working

There is a constant humming/buzzing on the subwoofer (Something isn't earthed properly and I think it's from the AC line). It gets louder when I touch the (insulated) SLINE (pin 1) wire.

The only one thing I haven't done is ground Pin 3 to the actual chassis of the subwoofer.

I've also compared it to jseaber's diagram and I've noticed a massive difference in the resistor values. How much of a difference does this make, I'm wondering?

Any help would be greatly appreciated.

Hello DarkStarZN! I dont know if i can help you any more, but i write nevertheless
I saw this thread a few days ago. I bought the Logitech Z 2300 Subwoofer+Satelite Speakers from a secondhandshop for only 2€!!!! But unfortuanatly it hasnt the Controller. So i looked up and found this Thread here. I build everything the same as HxCxK´s diagram. After that, i noticed also a lot of humming and buzzing. The Basscontrol also worked not properly(couldn´t made the Bass completely silent). So i started to make some changes:

Also i connected Pin6+Pin3 and Pin12+Pin3 with each a 270 Ohm resistor. And it is important to use a shielded cable(Improoved the humming a lot). So now i have a working, good Soundsystem with a lot of Bass for only 2€
Thanks alot for the schematic HxCxK

Tobi

(Sorry if my english is not the best, im from Germany)

Hi 20pyro00

Thanks for posting this

What is the point of your mod of the 2x 270 Ohm resistors across the L + R inputs. To reduce hum?

and now for my bad German just to return the favour

Zum welchen Zweck hast Du die 2x 270 Ohm Wiederstande über die L + R Eingänge? Gegen Brummen?

THanks

TIm

Hi Tim,
Yes, they reduce humming a lot. And the audio is still pretty loud.

Tobi

Ok thanks so much for this.
I am reviving a Z4 subwoofer, I will be adapting all of the above information for that.

Another Favour
Could you tell me the power rating of the potentiometers you used?


also:

Re the discussion of 5K vs 10K, linear vs logarithmic

here is an image from another blog where someone took apart a Z323 to repurpose the amp to power something else...

On this unit the subwoofer control pot is on the main board inside the speaker. To my eyes it's clearly 5K B (ie LINEAR)
[ his whole story is here: https://pcbisolation.com/blog/logitech-z340/ ]

Pretty clearly though you and other people here have a had good results with 10K.

OK for anyone else reading....

Have tracked down specs for the existing pots on the boards as per the circuit diagram above

The input volume pot is shown as a dual-gang APLS RK097122Z0 - I think it is meant to end Z05 and specs are here [registration required but no fee]

https://www.globalspec.com/specsearch/partspecs?partId={C0C01B95-6F15-45F5-A531-B63477BE4063}&comp=995&vid=139751&srchwebhitid=1718470111&srchitem=28&sqid=28897249

Max Resistance 10k Ohm
Operating voltage 50V AC

Again by my reckoning

P = V²/R = 2500/10000 = 0.25W


The sub pot is an ALPS RK09712200FS - specs here as explained above

https://www.globalspec.com/SpecSearch/PartSpecs?partId={938F29C9-72AD-46A8-8A8A-52677AFC2F3B}&vid=139751&comp=995

Max resistance 5K Ohm
Max voltage 50V AC

By my reckoning this means the max power P = V²/R = 2500/5000 = 0.5W

The elimination of R104 4K means that using a 10K pot the total resistance gained can be the same, however you can drive the sub harder I guess by aloowing the lower limit across the pot to be zero instead of 4K

Replacing them:

Unless you want to order 700+ of these, there is no way to substitute the exact same ones.

Bourns seem to make much the same ones.

Tim

Sources for your pots, at one-off:

The RK097122Z0
https://uk.rs-online.com/web/p/potentiometers/7293521/
;
And the obsolete RK09712200FS; a 50K version but that may be OK depending on the circuit; or if only one gang is used you could parallel the two gangs to give 25K.
**broken link removed**

Hi everybody, does anyone build a z2300 remote control pod and I can buy it from him ? I don't know nothing about electronics, printed circuit board and anything else, my control pod just Got broken and I can't use my logitech z2300 anymore. Since the control pod is to much expensive I was tough at a build one but I can't do it by myself. Thanks