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Hey guys, this is the first project I've done, a nearfield set of computer speakers, and I thought I would share the journey they took. If you want, just skip past all my BS and the project is below.
I bought some RS100's when they were on sale to play around with, thinking I would make an MTM with the Dayton neo, at this point I would suggest to others (not necesarilly myself) to plan your project well and stick to it, instead my mind wandered as it does when I start a woodworking project.... I sorta look at the wood until it tells me what it wants to be....sometimes it takes awhile.
So while I'm thinking MTM, something I had read got me thinking about dipole tweeters and I had some Optimus speakers with a Linaeum tweeter, maybe they would sound good in a nearfield setup. So the cabinet I had built for the MTM, was just tall enough to put the Linaeums at ear height, thats good right? So I looked at it some more and decided it should be a bipole, with sound coming from the back of the tweeter, there should be another speaker back there to match it, right? Well,I wasn't listening very well, thats not what it wanted to be at all.
I removed the rear speaker that didn't sound very good and noticed that I had a transmission line, like the Statements, sort of. I tried using the entire box volume with just the hole in the back and also the normal transmission line, but a single RS like that just wasn't getting low enough to reach the sub. They were sounding like there might be some potential but I needed to get more bass. A desktop 3-way didn't appear likely for a first project, but I did consider a side firing W5-876SD run from a plate amp. Well I had two more RS100's to use but with a tweeter that sits on top thats means you have to have a TMM. At this point I started seeing where this project had to go. Sealed lower RS for bass(snicker), transmission line RS, dipole tweeter, 2.5 way. Yeah, I laughed too. But thats what I was hearing........
To cut to the chase, I played around for a long time tweaking and getting close to something really nice sounding. My ARTA measurements weren't very good and I knew it. The big turnaround came thanks to Robert, who took some measurements for me in SE(unsmoothed). With that I went back to PCD and my crossover was pretty close but after some minor value adjustments it just gelled. These really sound good in the nearfield, very live with alot of depth, the wall behind my computer screen seems to be about 20 feet away when I'm listening.
The peak at 2K is resonance in the transmission line, I forgot the stuffing when we took the measurements. Now that it is properly stuffed, I suspect the peak is gone and I have a BBC dip through the crossover region. When I get my mic back from being calibrated we will see. If you zoom in its +/- 1db up beyond 10K, for some reason the top end (12K and up) looks terrible in PCD,the measurement in SE looked pretty good, I suppose its the scaling and an uncalibrated mic. Anyway they sound very nice with a sub to fill in the low end. When I get my mic back I will post final measurements and a crossover.
Well here it is, 2.5 way TMM, consisting of a Linaeum dipole tweeter, the upper RS100 is a "Statement" style open back transmission line, the lower RS100 is a .5 driver is sealed and stuffed. Footprint is 5.5" x 7.5" x 14.75", add 2 inches for the height of the tweeter. Not at all what I planned to build but it works very well for nearfield listening.
I bought some RS100's when they were on sale to play around with, thinking I would make an MTM with the Dayton neo, at this point I would suggest to others (not necesarilly myself) to plan your project well and stick to it, instead my mind wandered as it does when I start a woodworking project.... I sorta look at the wood until it tells me what it wants to be....sometimes it takes awhile.
So while I'm thinking MTM, something I had read got me thinking about dipole tweeters and I had some Optimus speakers with a Linaeum tweeter, maybe they would sound good in a nearfield setup. So the cabinet I had built for the MTM, was just tall enough to put the Linaeums at ear height, thats good right? So I looked at it some more and decided it should be a bipole, with sound coming from the back of the tweeter, there should be another speaker back there to match it, right? Well,I wasn't listening very well, thats not what it wanted to be at all.
I removed the rear speaker that didn't sound very good and noticed that I had a transmission line, like the Statements, sort of. I tried using the entire box volume with just the hole in the back and also the normal transmission line, but a single RS like that just wasn't getting low enough to reach the sub. They were sounding like there might be some potential but I needed to get more bass. A desktop 3-way didn't appear likely for a first project, but I did consider a side firing W5-876SD run from a plate amp. Well I had two more RS100's to use but with a tweeter that sits on top thats means you have to have a TMM. At this point I started seeing where this project had to go. Sealed lower RS for bass(snicker), transmission line RS, dipole tweeter, 2.5 way. Yeah, I laughed too. But thats what I was hearing........
To cut to the chase, I played around for a long time tweaking and getting close to something really nice sounding. My ARTA measurements weren't very good and I knew it. The big turnaround came thanks to Robert, who took some measurements for me in SE(unsmoothed). With that I went back to PCD and my crossover was pretty close but after some minor value adjustments it just gelled. These really sound good in the nearfield, very live with alot of depth, the wall behind my computer screen seems to be about 20 feet away when I'm listening.
The peak at 2K is resonance in the transmission line, I forgot the stuffing when we took the measurements. Now that it is properly stuffed, I suspect the peak is gone and I have a BBC dip through the crossover region. When I get my mic back from being calibrated we will see. If you zoom in its +/- 1db up beyond 10K, for some reason the top end (12K and up) looks terrible in PCD,the measurement in SE looked pretty good, I suppose its the scaling and an uncalibrated mic. Anyway they sound very nice with a sub to fill in the low end. When I get my mic back I will post final measurements and a crossover.
Well here it is, 2.5 way TMM, consisting of a Linaeum dipole tweeter, the upper RS100 is a "Statement" style open back transmission line, the lower RS100 is a .5 driver is sealed and stuffed. Footprint is 5.5" x 7.5" x 14.75", add 2 inches for the height of the tweeter. Not at all what I planned to build but it works very well for nearfield listening.
Attached Files