new bluetooth amp to hook up to old Logitech z2300 2.1 system?

Forums › Home Theatre (including HTPC and EPG Collector) › new bluetooth amp to hook up to old Logitech z2300 2.1 system?

Digikiwi

32 posts

Geek

#289496 9-Sep-2021 09:18

Kia ora koutou,

I'm a bit of an audio noob (or have fallen back down there since it's been decades). I prefer to repair or reuse rather than add to landfill

My ancient Logitech Z2300 2.1 system recently gave up the ghost. It makes no discernible noise when switched on, but the power light on the cabled remote still comes up I've pulled it apart but can't find any obvious fault, and don't really know what I'm doing with my multimeter. However, rather than learn how to fix it I'm thinking to just use the subwoofer and speakers which ought to still work fine to hook up to something like this Fosi_BT30D bluetooth amp.

I would be removing the the coil and circuitry of the old board inside the zx2300, as these would be scrap now.

Then I'd like to plug the speaker cables from the subwoofer into the passive subwoofer outlet on the new amp, and similarly the satellite speakers into the passive speaker outlets. Is this going to work or would I need a separate subwoofer amp to make the subwoofer work as an active subwoofer?

Would these 2 satellite speakers and 1 subwoofer be a good match for this amp? Or is a 10W per channel increase likely to blow those satellites at volume? Similarly, will a bass output of only 100W cf the original 120W be too weak or create undesireable load on the amp?

Logitech z2300 specs:

Audio Quality Certification: THX certified

Total RMS Power: 200W [FTC Rated Power]

System THD: Better than 0.05% before clipping

Total Peak Power(RMS): 400W less than 10% THD

Power distribution: 120 W (Subwoofer) + 2 X 40 W (Satellites)

Subwoofer: 120 W @ 8 ohms @ 10% THD @ 100Hz

Subwoofer Size (inch): 8

Subwoofer Type: Long throw

Satellites: 80 W (2 X 40 W) @ 8 ohms @ 10% THD @ 1kHz

Satellite Size (inch): 2.5

Satellite Type: Polished aluminum phase plug driver

Frequency response: 35 Hz - 20 kHz

Signal to noise ratio(SNR): @ 1kHz at 100dB

Sound Pressure Level (SPL): 117db

Subwoofer dimensions(HWD): 11" X 11" X 15"

Satellite dimensions(HWD): 6.75" X 3.5" X 6"

Total weight : 15 Kg

The fosi amp has the following specs:

Model: BT30D

Chippest:TPA3116D2

Maxpower Output: 50W*2+100W

THD: 0.05%@output 1W; SNR ≥98dB

Working Voltage: 12-24V

Speakers Frequency Response: 20Hz-20kHz(±3dB)

Bass Cutoff Frequency Range Adjustment: 40-300Hz

Device Dimension: L118 x W132 x H35 mm/4.72 x 5.2 x 1.38inch

Input mode: Bluetooth/RCA

Output mode: Passive Speakers + Passive/Active Subwoofer

Bluetooth: Bluetooth 5.0, up to 15m/49ft wireless range without hindrance

Easy Connection

Bluetooth Network Name: FOSI AUDIO

Wireless Range: Up to 15m/49ft.

Works with All of Today’s Latest Bluetooth Devices(IOS, Android, Smartphone, Pad, Tablet etc.)

Package Include:

*1x BT30D Amplifier

*1x 24V 4.5A Power Supply (I'd need to wire an NZ plug on)

rhy7s

625 posts

Ultimate Geek

#2775153 9-Sep-2021 10:48

It's often the control pod that goes on the Z-2300, you might want to look at further troubleshooting or taking a punt on a replacement.

Digikiwi

32 posts

Geek

#2775162 9-Sep-2021 10:52

Thanks for your reply, I replaced the control pod years ago, but this time I don't get any crackle or other sound when flicking switch at the back of the sub, so I doubt it's the control pod - its LED still comes on.

rhy7s

625 posts

Ultimate Geek

#2775168 9-Sep-2021 10:58

Sorry if this sounds basic, just double checking that the fuse was OK when you pulled it apart?

Digikiwi

32 posts

Geek

#2775171 9-Sep-2021 11:02

Yes, it passed both visual inspection and Multimeter test. I should have mentioned that, sorry.

Digikiwi

32 posts

Geek

#2799712 22-Oct-2021 21:18

Hi,

Just wanted to leave a note to say that what I set out to do totally worked.

After not getting any answers on a coupld of forums, I though bugger it, and bought the Fosi Amp BT30D from AliExpress (and it came bloody quick too). Then proceeded to rip the guts out of the subwoofer in terms of circuit board, copper coil, heat sink, AC socket etc. I screwed a piece of hardwood on the gap left by the removed heatsink and filled any holes with a hot glue gun, and also used that glue on the wood to metal interface before screwing it on tight. I used one of the holes to glue in a plug for the subwoofer wire connectors, again seated in hot gun glue. Time will tell if that is a lasting solution, but having put on big blobs from both sides should work quite well at keeping it seated.

For the satellites speakers, I used ones from my old Klipsch promedia THX 5.1 system rather than the Logitech ones from the Z2300. The reason is they sound great and handle up to 80W rather than 40W for the latter (I didn't want to risk blowing these with the 50W RMS from the Fosi amp).

The result - for a non hifi guy like myself it sounds bloody marvelous and I'd recommend it's worth a crack if you have a dead amp on your great quality computer/home theater speaker system. For NZ$100, give or take I've got a great system with bluetooth capability. Better than landfilling and buying a new system that might be of lesser quality (I did my research back in the day and both the Z2300 and Klipsch promedia THX are legendary to this day in terms of speaker quality in their class).

Cheers

Digikiwi

32 posts

Geek

#2799728 22-Oct-2021 23:09

And just in case I lead someone up the garden path - I've been digging around the net to find the specs for the Klipsch Promedia 5.1 system in terms of output.

Not 80W for the satellites but 5 x 60W @ 6 ohm, plus the 2 x 8inch woofers pushing 170W @ 6 ohm.

My next project is to find a suitable amp to drive those Klipsch subwoofers and 2 of the satellite speakers for the lounge system. Not sure I'll find a 60W RMS with 170W Sub combo or near enough to those specs. I suspect anything pushing approx 150 to the sub will have a higher rating on the satellites, risking blowing them.