I have a full HT system but use a Yamaha sound bar (2xTMW) for general daily use. I was looking to build a little woofer to add some lower end and body for when I watch TV movies etc.
Did a design I then looked around for a little plate amp or build an active stage (buffer/filter/phase) to partner a Class D amp. While researching a plate amp I found a completed sub for A$89 delivered from DJ City in Melbourne to Newcastle. The idea was to strip out the amp.
It's a Fenton SHFS08B which is cheap and cheerful and even though there's a lot wrong with the design and build, it works well to add some bottom end to the soundbar. Sure the bass is a bit one note and the gain must be a zillion dB but it saves me building one at a much greater price. How do they sell it so cheap as there is 10% GST plus shipping? I'm amazed how cheap this thing is and it even comes with a removable IEC lead.
The amp looks like Class D and the active stage uses 4558 op amps. The only thing I had to do was add a gasket to the woofer, seal the hole for the speaker wire and countersink the screw holes.
The specs are very optimistic and can be found here:
SHFS08B Active subwoofer 8" black - Speakers - Home HiFi - Tronios.com
Did a design I then looked around for a little plate amp or build an active stage (buffer/filter/phase) to partner a Class D amp. While researching a plate amp I found a completed sub for A$89 delivered from DJ City in Melbourne to Newcastle. The idea was to strip out the amp.
It's a Fenton SHFS08B which is cheap and cheerful and even though there's a lot wrong with the design and build, it works well to add some bottom end to the soundbar. Sure the bass is a bit one note and the gain must be a zillion dB but it saves me building one at a much greater price. How do they sell it so cheap as there is 10% GST plus shipping? I'm amazed how cheap this thing is and it even comes with a removable IEC lead.
The amp looks like Class D and the active stage uses 4558 op amps. The only thing I had to do was add a gasket to the woofer, seal the hole for the speaker wire and countersink the screw holes.
The specs are very optimistic and can be found here:
SHFS08B Active subwoofer 8" black - Speakers - Home HiFi - Tronios.com
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A final comment for the record.
After playing a few movies through it I did some mods to improve it's use with a soundbar.
The bottom end certainly provided some rumble but not controlled so changed it to sort of sealed by filling the enclosure with damping material, filled the port with tightly wrapped damping, coated the driver with LTS50. Bass is no longer one note and better controlled but has a lost of some extension which is a good compromise for the soundbar.
The feet were changed to rubber (door stops) as they were rattling on the polished floor due to the down firing woofer. The original units were plastic with rubber inserts which compress so much they were of no use so it was plastic against timber floor. Would be OK for carpet floors.
No hum, pops or buzzes so at this stage the amp seems to work without issues.
After playing a few movies through it I did some mods to improve it's use with a soundbar.
The bottom end certainly provided some rumble but not controlled so changed it to sort of sealed by filling the enclosure with damping material, filled the port with tightly wrapped damping, coated the driver with LTS50. Bass is no longer one note and better controlled but has a lost of some extension which is a good compromise for the soundbar.
The feet were changed to rubber (door stops) as they were rattling on the polished floor due to the down firing woofer. The original units were plastic with rubber inserts which compress so much they were of no use so it was plastic against timber floor. Would be OK for carpet floors.
No hum, pops or buzzes so at this stage the amp seems to work without issues.
Thanks for your review. I had just purchased one, mostly due to the price, but it hadn't received too many negative reviews so I was happy to order it. It hasn't arrived yet but now I am a little concerned about something slightly unrelated to your post, so I'm hoping you can help me with it.
My amp has a dedicated sub-out but they are bare-wire terminals. The Fenton SHFS08B has RCA line in (L+R). How am I supposed to connect the +/- of the bare-wire terminals to L+R of the subwoofer? Any help will be most appreciated.
My amp has a dedicated sub-out but they are bare-wire terminals. The Fenton SHFS08B has RCA line in (L+R). How am I supposed to connect the +/- of the bare-wire terminals to L+R of the subwoofer? Any help will be most appreciated.
Just pop to your nearest electronics part store and get RCA connectors and some speaker wires: Black - RCA HIGH QUALITY Gold Plug | Jaycar Electronics
Can't solder? Get some with screw terminals (might not be high fidelity, but it's just a sub 😉 )
RCA Plug with Screw Terminals | Jaycar Electronics
Similar is available from your local friendly mass auction site 😉
Just make sure your amp sub out is line level..
Can't solder? Get some with screw terminals (might not be high fidelity, but it's just a sub 😉 )
RCA Plug with Screw Terminals | Jaycar Electronics
Similar is available from your local friendly mass auction site 😉
Just make sure your amp sub out is line level..
I've never come across a sub out that are just terminals. As above just make sure they are line level and not speaker level (the sub does cater for those as well).
Get a RCA Y cable and cut off the connector on the single end and expose the centre wire and shield and make sure of no loose strands. These should be able to be tidily connected to the terminal. Some examples from Jaycar and depending on the run, one should do the job. If a long run required, then don't cut the Y cable but one end of the single RCA extension cable.
2 x RCA Plugs to 1 x RCA Socket - 300mm | Jaycar Electronics
RCA Plug to 2 x RCA Sockets Audio Cable - 300mm | Jaycar Electronics
RCA Plug to 2 x RCA Plugs Audio Cable - 1.5m | Jaycar Electronics
In addition to post #2, the port has been blocked with a solid sink drain plug.
Get a RCA Y cable and cut off the connector on the single end and expose the centre wire and shield and make sure of no loose strands. These should be able to be tidily connected to the terminal. Some examples from Jaycar and depending on the run, one should do the job. If a long run required, then don't cut the Y cable but one end of the single RCA extension cable.
2 x RCA Plugs to 1 x RCA Socket - 300mm | Jaycar Electronics
RCA Plug to 2 x RCA Sockets Audio Cable - 300mm | Jaycar Electronics
RCA Plug to 2 x RCA Plugs Audio Cable - 1.5m | Jaycar Electronics
In addition to post #2, the port has been blocked with a solid sink drain plug.