Logitech Z-2300 Subwoofer Disassembly

Curiosity inspired me to take apart my Z-2300 subwoofer. The grill pried off without much difficulty, and I was even able to reassemble it with minimal cosmetic damage.

WARNING: Perform this disassembly with extreme caution! The enclosure contains a 120V AC transformer. With the Z-2300 turned on, unplug the power cord and wait for the power LED to fade. This will drain the capacitors and minimize the possibility of shock.

Various facts discovered:

  • Subwoofer uses an 8 screw mounting pattern
  • Subwoofer impedance measured at DC: Single voice coil, 6.5 ohms (8 ohms as per specs)
    • The amplifier had no problem driving an external 4 ohm subwoofer in a separate enclosure.
  • Subwoofer construction: Corrugated paper and foam surround.
  • The Z-2300 uses a JRC4565 operational amplifier for pre-amplification and an unidentified chip amp for output amplification
  • EDIT: Satellites and subwoofer use TDA7296 and/or TDA7295 Class AB amplifier IC’s (identified by judeh101)

Potential modifications:

  • As others have done, the enclosure could use some sound dampening material.
  • Replacing the subwoofer with a better made 8″ woofer (polypropylene cone and rubber surrounds) would probably improve sound quality. The amp can handle 4 ohms (based on my limited testing), which means output might even be stronger with such a woofer. However, the amplifier’s 150Hz crossover is fairly high and should ideally be reduced to below 100Hz. If I get around to replacing the sub, I’ll figure out the amplifier circuitry and post that modification.

82 Replies to “Logitech Z-2300 Subwoofer Disassembly

  1. According to RishiGuru 01-01-2011 at Tomshardware
    the Subwoofer is not Tang Band:
    “…Note: Normally people confuse this bass driver as used in Z-680, Z-2200 & Z-2300 with the Tang Band W8-670Q model. Though both units look near identical, Z-2300’s bass driver is different from the W8-670Q in the rear section. It became absolutely certain when my friend’s Z-2300 bass driver went dead and I have to personally contact TangBand via email to ask the model of the driver used in Z-2300 & its price. I also send them the above pictures of the driver to help them identify. To my surprise, they replied after inspecting the pictures sent to them, that this bass driver do not belong to them or in any way or represent any one of their models. But they did agree that they supplied W8-670C drivers for Z-560″…

  2. I just disassembled mine and hooked the amp up to a kicker 12″ competition sub in a ported box. WOW! does this guy slam.

  3. Hello,

    maybe someone know where is sattelite speakers filter and what could be done for it to widen frequency range from lower, because i missing middle tones.

    Thank You,

  4. Is it possible to make some photos from the Amp of the Z 2300 ?
    I would be interested how much I would be interested how much µF electrolytic capacitors have both and like the other construction is.

    Can you make some pics please ?

    Thank you 🙂

  5. Hi there, my z2300 subwoofer works fine…but the ‘right’ port (to plug the speaker in) stopped working. Do you know if this is an easy fix. If so, how do I get to work again…b/c my speakers and everything else are working fine. Please help!! Thanks!

  6. Hi, great write up.. love the control pod you made.. happy you made this blog post.

    My subsection of the amp has died, or at least my sub has stopped working but the sub was removed and tested and is fine, what would Check first ?

  7. Can anyone help me… My speaker z2300 is not working., only subwoofer hears, and a minute sound on speakers while playing music, when I asked , someone says that’s its ic may be dead.. Can anyone help?

  8. Hi Jseaber!
    I have had my Z-2300 collecting dust for years as I’ve upgraded to “real” speakers and amp but I have used it for trips where it has been possible to take it with me.
    I have been wondering how easily would it be possible to modify the amp to run on a battery as well.
    I’m interested in building a whole single box for all speakers and electronics so it would be more portable, perhaps adding wheels on the box too.
    Battery could be a car battery or some lithium battery as those are pretty affordable these days.
    I have no degree or certification in electronics but I know my way around solder iron and pcbs to a certain degree.
    I have still to disassemble the speakers or plan much anything other than ideas in my head, but I need to know somehow if it’s possible to run it from a battery and I don’t think battery and an inverter would be a smart choice.

    1. Hey Jere, I have a couple ideas for you.

      One way to power the Z-2300 from battery is to use a 12v inverter and not modify the Z-2300 at all. This is really inefficient, but a friend of mine does it this way in his car.

      The toroidal transformer (the big round wire-wound thing) provides 2 ~20VAC supplies to the amp which are rectified (turned into DC from AC) to about +18V and -18V (audio amps require positive and negative voltage to operate properly)

      The datasheet for the amp chips say that can take between 10v and 35v, so two batteries between those voltages should work.

      Connected like this:

      A+[===]- ~B~ +[===]-C

      A: To amp positive power input (DC+ side of rectifier diodes should work)
      B: amp Power (virtual) Ground
      C: To amp negative power input (DC- side of rectifier diodes)

  9. did you ever find out what capacitor to use to make the sub 100hz( thingys line with line input) or can u link me to a capacitor that will bring it down a little -thanks in advance

  10. +1 kev’s request.

    The thread lives on! I picked up a z-2300 sub and remote only (I already have a complete set), and I’m looking to reduce the crossover from sub to satellite to around 80-100hz. Purpose is to use bookshelf speakers to replace non-existent satellites in the second unit. Based on Von’s post above (from how many years ago?), it appears this is possible.

    Please offer help if you can!

    1. Working on a bunch of z2300’s right now. On the main board there’s one opamp visible surrounded by 6 large caps. In it’s feedbackloops there are 2 ceramic caps per side plus some resistors. That, i suspect, is the crossover for the high side of the sound. It’s stereo and I would figure a smart designer would do the bass end of it after the mono conversion. This would mean that if you wanted to alter the highfrequency cutoff you could tinker with those parts but if you wanted to modify the bass cutoff you’ll need to take the whole board out and see what’s underneath.

      1. If you’re working on a lot of these speakers you’ve probably already figured out how to remove the board, but if you’d like to compare notes, here’s what I found:

        There are 5 screws with plastic spacers holding the board to the back panel (which itself is secured to the cabinet by 22 screws around the perimeter). Additionally the D-Sub connector has 2 hex-headed screws which hold it in place, as well as a bunch of epoxy. There is also 1 screw holding the RCA connectors in place. Not to forget the 5 screws securing the chips to the heatsink, as well as a green ground wire. With all these removed, the epoxy and glue around the D-Sub and RCA connectors can be pried away from the back panel. It is best to do this carefully to keep as much of it as intact as possible, since they also form an airtight seal. Lastly, the black wire from the board to the transformer has to be cut. The red and black speaker wires can be disconnected from the speaker (sub), as well as the green and red wires with blade connectors. At this point the board can come free along with the RCA connector board. Just beware of a lot of messy white thermal paste at the heatsink.

        In my case, I’ve gone through all this in the hope of fixing a hum / buzz coming from the sub. Actually, from the transformer, since the hum is present even with the subwoofer’s speaker wires disconnected. If you have any ideas on a diagnosis or fix, please do share!

  11. Hi, i know the posts are a while old, but didnt find much else on the web about “tuning” the logitech z-2200. So i had the idea (if its possible), to us only the ams of the module without the internal x-over stage and getting signals from my mini dsp…and in return get an “small” and affordable plate amp i can configure with any setup i want.
    the question is, is it possible to get around the x-over stage directly on the amps with a line signal? And how could this be done? :-).
    Would be realy nice to get some advice, if or not this could be done.

  12. My Z-2300 has developed a hum/buzz which is present as soon as the sub is plugged in and switched on, without any signal input and even with the control pod switch off or disconnected. Any tips on diagnosing or fixing the hum is really appreciated!

    I have already checked the two large filter capacitors (10000 uF Samxon) and their measured capacitance still matches their rating.

    I have previously reflowed the solder on the control pod’s headphone jack, which had started having intermittent connection problems due to lots of use over the years. I hope I can repair and keep using these great speakers!

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