Silent Screamer Posted October 19, 2021 Share Posted October 19, 2021 I know most people place the port at the bottom of the speaker, but is there a reason for it? From everything I am reading / watching you want to basically try and have the sound as central to the tweeter as possible, so if putting the port at the top of the box achieved that why wouldn't you do it? Purely looks or another reason? or you would do it given the chance? 1 Link to comment Share on other sites More sharing options...
Ittaku Posted October 19, 2021 Share Posted October 19, 2021 Bass is omnidirectional so it doesn't matter where the port is. On the other hand, ports radiate unwanted sound from within the box as well (coming from the rear of drivers facing into the box and the box's resonances), so you may want to minimise that by putting it somewhere so far off the listening axis that its effect is minimised. 1 Link to comment Share on other sites More sharing options...
mwhouston Posted October 19, 2021 Share Posted October 19, 2021 26 minutes ago, Silent Screamer said: I know most people place the port at the bottom of the speaker, but is there a reason for it? From everything I am reading / watching you want to basically try and have the sound as central to the tweeter as possible, so if putting the port at the top of the box achieved that why wouldn't you do it? Purely looks or another reason? or you would do it given the chance? Im a port out the back kind-of-man. Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 19, 2021 Author Share Posted October 19, 2021 I've been playing around with some new cabinet designs, and the port could go at the top or the bottom just as easy. Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 19, 2021 Author Share Posted October 19, 2021 1 minute ago, mwhouston said: Im a port out the back kind-of-man. Not sure the current design would lend itself to that. Is the a particular reason for that? Cancellation? Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 19, 2021 Author Share Posted October 19, 2021 Link to comment Share on other sites More sharing options...
Batty Posted October 19, 2021 Share Posted October 19, 2021 My Castle Howards port the 1/4 wave TL through the base of the cabinet, they are held off the plinth by 4 spacers which can be changed to suite the room. Therefore they port to the outside world all around the base. 1 Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 20, 2021 Author Share Posted October 20, 2021 6 hours ago, Batty said: My Castle Howards port the 1/4 wave TL through the base of the cabinet, they are held off the plinth by 4 spacers which can be changed to suite the room. Therefore they port to the outside world all around the base. Polk Audio did that a fair bit. A power port I think they called it. Link to comment Share on other sites More sharing options...
davewantsmoore Posted October 20, 2021 Share Posted October 20, 2021 23 hours ago, Silent Screamer said: port depends what frequencies are coming out of the port ... and also if you want to use the floor/wall/etc to increase the load on the port. Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 20, 2021 Author Share Posted October 20, 2021 (edited) 45 minutes ago, davewantsmoore said: depends what frequencies are coming out of the port ... and also if you want to use the floor/wall/etc to increase the load on the port. Well considering the person I need to build these particular speakers wants more bass we'll be keeping the same tweeter and mid in cup from the current box (I built these speakers 22 years ago), I guess rear ported down low to get some loading? Edited October 20, 2021 by Silent Screamer Link to comment Share on other sites More sharing options...
davewantsmoore Posted October 20, 2021 Share Posted October 20, 2021 48 minutes ago, Silent Screamer said: I guess rear ported down low to get some loading? That will make the port behave like it is longer. Do you want that? Depends on the design. Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 20, 2021 Author Share Posted October 20, 2021 27 minutes ago, davewantsmoore said: That will make the port behave like it is longer. Do you want that? Depends on the design. For this particular speaker I need all the bass I can get. I am just trying to use up some old Jaycar CS-2246-12 drivers I have sitting around. Trying to do it on a budget. Might be easier to just do a down firing one. Link to comment Share on other sites More sharing options...
davewantsmoore Posted October 21, 2021 Share Posted October 21, 2021 21 hours ago, Silent Screamer said: For this particular speaker I need all the bass I can get. A lower tuning (longer port) will generally give you less bass.... but it's all swings and roundabouts. Only very detailed simulations can really show what's going to happen in any detail... and even then, build and measure (repeat) is king. 2 Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 21, 2021 Author Share Posted October 21, 2021 13 minutes ago, davewantsmoore said: A lower tuning (longer port) will generally give you less bass.... but it's all swings and roundabouts. Only very detailed simulations can really show what's going to happen in any detail... and even then, build and measure (repeat) is king. I am kind of reluctant to build these new speakers. The guys who owns the speakers doesn't need a lot more bass, but the younger guy that lives with him does, he wants doof doof. Ordinarily I would say bugger the young guy they are your speakers, but he took the guy in as a kid and has lived with him for about 30 years (that I have known them both). He is like a son and I can't see him leaving home any time soon. Expect he will inherit the house when my friend passes. The current speakers have a 6.5" Vifa P17WJ00 and I don't know if the 12" Jaycar drivers are going to take it from mild bass to doof doof. I don't know if anything short of the 18" drivers I have here are going to satisfy the bass needs. Trying to do it on a budget, I don't know if I am pushing it up hill. Almost need an extra sub each side, but that then turns it into a 4 way speaker. Link to comment Share on other sites More sharing options...
Ittaku Posted October 21, 2021 Share Posted October 21, 2021 1 hour ago, Silent Screamer said: I am kind of reluctant to build these new speakers. The guys who owns the speakers doesn't need a lot more bass, but the younger guy that lives with him does, he wants doof doof. Ordinarily I would say bugger the young guy they are your speakers, but he took the guy in as a kid and has lived with him for about 30 years (that I have known them both). He is like a son and I can't see him leaving home any time soon. Expect he will inherit the house when my friend passes. The current speakers have a 6.5" Vifa P17WJ00 and I don't know if the 12" Jaycar drivers are going to take it from mild bass to doof doof. I don't know if anything short of the 18" drivers I have here are going to satisfy the bass needs. Trying to do it on a budget, I don't know if I am pushing it up hill. Almost need an extra sub each side, but that then turns it into a 4 way speaker. Make them with a port, and a plug for the port. The older guy can listen with them in acoustic suspension mode, and Mr. Doof Doof can take the port plug out and doof his brains out. 2 Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 21, 2021 Author Share Posted October 21, 2021 1 hour ago, Ittaku said: Make them with a port, and a plug for the port. The older guy can listen with them in acoustic suspension mode, and Mr. Doof Doof can take the port plug out and doof his brains out. Not a bad idea. Link to comment Share on other sites More sharing options...
Silent Screamer Posted October 22, 2021 Author Share Posted October 22, 2021 Decided it will probably be easiest to just build the port outside the box. That way if I want to turn it into a sealed box it is just a matter of blocking off the port holes. Also if I need to change the port dimensions that would also be easier from the outside. Just need some mounting points. Link to comment Share on other sites More sharing options...
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