Considering it's such a long/large vent, no, which BTW will have some strong pipe harmonics that will comb filter with the driver's, and especially the main's, output if not damped at least by ear. It's these types of distortion that keep many small subs from 'disappearing'.
Hmm, still not clear after looking at this, but since you're clipping off a piece, so just carry it with you to show what you need, assuming it's not a long run of course: http://www.soundhobby.com/photo gallery/09. 300w bash amp_photo.htm
I would as amps vibrate [hum], so conceivably a leak could develop over time, especially if the wood screws didn't cinch it down sufficiently uniform around its perimeter to start with and if it doesn't come with a gasket I recommend making one out of a nonporous material such as neoprene foam window sealing tape.
GM
Hmm, still not clear after looking at this, but since you're clipping off a piece, so just carry it with you to show what you need, assuming it's not a long run of course: http://www.soundhobby.com/photo gallery/09. 300w bash amp_photo.htm
I would as amps vibrate [hum], so conceivably a leak could develop over time, especially if the wood screws didn't cinch it down sufficiently uniform around its perimeter to start with and if it doesn't come with a gasket I recommend making one out of a nonporous material such as neoprene foam window sealing tape.
GM
OK, that's good news. I figured the 2mm gap would simply make the port a tiny bit longer (like adding a 19cm x 1.7 x 2mm piece to it) which should lower the tuning frequency by a fraction of a hertz.
Regarding the "pipe harmonics", is this something inherent to all big sub boxes? What could I have done inside this box to prevent it from occurring?
Thankfully my plate amp includes a pre-installed gasket.
I checked two hardware stores, all they have is 1.5mm hard electric wire. By hard I mean it's very stiff (needs a bit of force to bend), and it has no strands - it's a solid piece of wire.
Anyway, I was told that I should compare the resistance of both wires. Can anyone confirm that it actually matters?
I looked at the wire that came with the amp, it says 18AWG ,105C (celsius), 600V. Should I care about any of the specs other than 18AWG, and is it OK that the electric wire I bought is somewhat thicker, and possibly of different resistance?
Anyway, I was told that I should compare the resistance of both wires. Can anyone confirm that it actually matters?
I looked at the wire that came with the amp, it says 18AWG ,105C (celsius), 600V. Should I care about any of the specs other than 18AWG, and is it OK that the electric wire I bought is somewhat thicker, and possibly of different resistance?
18 awg is your typical "lamp cord", often found in extension cords. Get one and cut it up...
Often sold in bulk in audio stores as "18 gauge speaker wire".
Often sold in bulk in audio stores as "18 gauge speaker wire".
I have two spare cables, one is meant for use with computer cases/monitors and such, and the other is connected to a dead receiver. They're both the same model, ho5vv-f, and by Googling this model I found that it's rated for 300V/500V and up to 60 degrees Celsius. Looking inside those cables, though, their inside wires are of similar (if not identical) thickness to the one that came with my plate amp. Not sure if I should use them...
Guys, it appears I made a slight mistake. Right before I ordered the box, I decided to go with a vent that's 3.5cm high instead of 3cm. That requires extending the port length from 75cm to 93.5cm, which I forgot to change in the sketch. So I played with winISD a bit and it looks like this changes the tuning freq of my box from 20hz to 22hz.
I compared the SPL graphs of both boxes and there's a 2db difference in 18hz. Should I bother with adding another piece to the port to get it to 93.5cm or is this a negligible difference? Oh and the -3db point is moved from 19hz to 20hz.
I compared the SPL graphs of both boxes and there's a 2db difference in 18hz. Should I bother with adding another piece to the port to get it to 93.5cm or is this a negligible difference? Oh and the -3db point is moved from 19hz to 20hz.
At the frequencies involved, I highly doubt you'll be able to hear any difference. Time I think to relax and try to enjoy the fruits of your labours.
Yeah, I'm dying to finally use it. Last night I finished painting with the white gloss paint, today I'll do the front and rear in matte black, but I think ill mix the two colors to get a dark grey instead of a pure black.
Almost ready! Done painting, now waiting for T nuts and bolts to arrive.
Full album:https://goo.gl/photos/ijuwPRyTAmxUbYtKA
Full album:https://goo.gl/photos/ijuwPRyTAmxUbYtKA
An externally hosted image should be here but it was not working when we last tested it.
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Me neither; the problem folks typically have is the nuts working loose and either falling off or 'hog out' the MDF due to improper installation, keeping it from being tightened sufficiently or worse, can't get the screw/bolt out when they [try to] remove the driver, which can be several times if experimenting with stuffing density.
GM
GM
Well it looks like I can't use most of the screw points on the plate amp. It has 10 screw holes, I can only use the 4 ones on the corners. I double checked the cutout on the cabinet and it's spot on like they specify on Parts Express' website: 10" x 6.25". And yet, when I insert the plate amp into the cutout, I cannot align it so that there's space to drill the other 6 screw holes. I can see into the cabinet through the screw holes either on top or bottom of the amp, which means I cannot use the 3 on either side.
Is it OK to only use the 4 screw holes on the corners?
Is it OK to only use the 4 screw holes on the corners?
Probably, but of more concern to me is how good will the seal be with so little overlap? Tighten down just the corners and depending on the amp's construction and gasket quality it may not seal well enough over time for a vented alignment.
Link to the amp?
GM
Link to the amp?
GM
Bash 300S Digital Subwoofer Plate Amplifier 300W RMS
Perhaps I could use double-sided tape on the areas where screws can not be used.
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Not a bad idea... Also confirm that the "see through" holes are covered, too. Once you are playing the system, pass your ear over the plate and listen for "chuffing", just to make sure that you have a good seal.
Looks like you need to use all of the holes and an overlap = the gasket width if it's like this 500S shown here: http://www.parts-express.com/Data/Default/Images/Catalog/Original/888-752_ALT_1.jpg
Scanning reviews points out sealing and cooling issues with this amp, so if it were me, I'd get some sheet metal strips, extra neoprene gasket material and gasket/clamp the amp in place using the four corner screws to index it to the box. The clamp strips should be wide enough to allow the screws to be located outside the amp plate, so it's just 'pinched' to the box.
The various double stick tapes I've experience with can be such a 'pain' if one has to remove/replace whatever it's holding and if it has/ever develops a leak, then a mess to clean off/replace and judging by reviews, this unfortunately may be in your [near/immediate] future if you drive it hard.
GM
Scanning reviews points out sealing and cooling issues with this amp, so if it were me, I'd get some sheet metal strips, extra neoprene gasket material and gasket/clamp the amp in place using the four corner screws to index it to the box. The clamp strips should be wide enough to allow the screws to be located outside the amp plate, so it's just 'pinched' to the box.
The various double stick tapes I've experience with can be such a 'pain' if one has to remove/replace whatever it's holding and if it has/ever develops a leak, then a mess to clean off/replace and judging by reviews, this unfortunately may be in your [near/immediate] future if you drive it hard.
GM
These things would be impossible to find in this country, as is everything else that I've had to get for this build so far. I'll have to rely on double sided tape.
I've already drilled two corners and had two power drills die in the process, so tomorrow I'll buy a new one and hopefully finish this pita build.
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