Subwoofer is Born

Due to some technical problems this wont be long and i wont post the booring things. Subwoofer is ready except the logo and the foundation havent been fit with steel screws. Whole structure is heavy enough to seal the bottom. Here is some info:

- external size: 360mm width, 400mm deep, 550mm height
- ~70L external volume, ~54L internal volume
- 5-6cm batting on all internal sides except front panel
- bass-reflecs tube, f80, 225mm long, two flared ports
- 4 port golden plated terminal
- wooden screws to the rest of the places
- speaker - Pioneer TS-W307D4, 12" inch (30cm cone), Composite IMPP Cone using Interlaced Aramid Fiber, Cone Reinforcement Arcs, Wide Roll Three-Layer Fiber Woven Radial, 4-Layer Long Voice Coil, Phenol Resin Coated Glass Cloth, Double Mass High-Power (83oz) Magnet Construction, Integrated Single-Sided Silver Compression Terminals, two voice coils (4ohm each), sensitivity 89db, 400W RMS, 18Hz - 500Hz

For test i used my old micro Hi-Fi 2x10W @4ohm (however the speaker has two modes - 2ohm and 8ohm so i went for 8ohm at one of the channels which makes no more than 5W at the output). Also there was no low-pass filter and many of the sounds like voice and so were hollow. Bass is clear and strong, still able to be heard around the apartment with closed doors. Only problem seems to be the grill, which starts to vibrate too easy, creating annouing sound. This effect was particially neutralized with adjusting the screws holding the speaker and the grill at same time but i wonder what would happen when more power is send to the speaker.

I'll give example of ready subs on the market for about the same price:

1) Jamo E3 SUB - 70W, 8 inch drive, a bit smaller size, 6.6kg
2) Sony SA-WM250 - 100W, 8inch drive (?), about same volume, 19kg
3) Pioneer S-W90S - 85W, 6,5inch (16cm) drive, 11,5kg

all of them are active subwoofers (built in amplifier). Active subwoofers dont have internal isolation which should make the sound softer. You cant place them in your trunk. Much less power. Frequency response is not bad but not that good. Speaker size is smaller and size does matter when we talk about sound and music. Not to mention the weight, concidering the similar size + built in amplifiers of some of the subs - they still are lighter.

I wanted to post full article here or on DC website but verry likely that wont be possible. Thats because the article seems like going to be sold pretty soon to bulgarian computer based website. I'll be able to give you the link but i dont know how you're going to translate it.

Article is been send few hours ago. It should be reviewed and published in next few days.

Logo has arrived (about a week ago) . It might sound strange but i still can't place it cause lack of proper "tools" to do that. It looks pretty cool actually. 1-2mm thick stainless steel and laser cutting machine is been used. Shots - maybe tomorrow or Sunday.

Logo or the sub?

don't know how much it weights exactly but its about 20-25kg, as for the cost - about $150 without the wood, screws, isolation, paint and logo (some of those i already had or i managed to get for free)

@Dopp
looks great, maybe you can give us a picture?!

Just finished with the logo. Also the problem with the bassreflex tube is now fixed as far as i managed to test at max power i can get (20W). The micro hi-fi system i'm still using to power up the sub is now running in mono mode and each speaker output (left and right) is attached at one of the two voice coils of the sub. Cause the micro system is made to run at 2x 4ohm load and each coil is 4ohm too, power supplied to the sub is now 4 times higher than before. You can see two black cables (one of each coil).

remote control unit

This is the amplifier, Sony TA-FE370. I think it will be boring to write some technical specifications so i'll skip this part and go directly to the practical impression.

First impression was that it has a good quality/cost ratio including a remote control. As example, Pioneer A-109 is rated with same price tag but provide less power and no remote control. Remote is also able to control tuner, tape decks, cd players, MD from Sony in case they comply on specific remote control standart - its still hard to say which model does and which dont. Signal input connections use RCA connectors - Phono, Tuner, CD, AUX, Tape2/MD, Tape1/DAT where Tape1, Tape2, MD, DAT also has RCA out for recording from other source connected to the amplifier. There is additional GROUND connector and 3 AC power connectors to power other devices.
One of the things i first saw infront was the volume control button which is one of the two big buttons (the one on the right) is not actually spinning a 360 degrees but it has a small marker and limited rotation, so i was wondering how remote control and this button will synchronize the volume if remote is used. It was nice surprise to see the volume button moving automatically when changing the volume level through the remote control
Something that was missing in the package is RCA cable so i had to buy one. To be more specific it is a stereo RCA cable - 2 RCA connectors at one end and 3,5mm stereo jack at the other hooked at AUX input and headphones output (like cellphone, micro hi-fi system or mp3 player). First test was with the speakers of the micro hi-fi system so i can test the balance, treble and bass and stereo. What it interesting for Balance, treble and bass buttons is when they come close to their default possition (50%) button "stick" like in a groove so you can be sure you have set balance to 50% as example. Second big button (on the left) switch the signal source and the scale in the middle has lights under the label of each signal source so you can see what you are running right now. There is also big jack for headphones and loudness (on/off). There is also a speaker switch which can turn off speakers if necessary. Turn on/off the amplifier is just like a TV - if its used the button on the front panel amplifier will be totally switched off and can be turned on again only through same button.
If amplifier is once working and shutted down remotely it goes to standby and indicator lights up, now it can be turned on remotely.
Then it was turn to plug the subwoofer (btw it seems to work in stereo ^^). First increased above the volume of the micro hi-fi (used the radio through headphones output) then increased the volume of the amplifier to about half which should be a bit under 70W, treble and bass remained at default (50%). I didn't go beyond 50% of the volume cause i have two common problems - 1) window above my room's door started to shake so much and loud that it can fell to the floor, and 2) subwoofer's membrane was also shaking hard so one specific sound starts to come up (which also shows if volume is a bit lower but bass is increased), this sound is hard to describe cause its not from bass distortion (like when it can't handle so low frequencies) but its caused of the membrane damping, its size, high speed and big amplitude which makes the air do "bzbzbzbz" or "dddddddd" well, hard to describe.