Posted March 12, 200817 yr It's finally time to re-do some things.Should be selling some stuff this weekend, which means I'm going to buy some plywood and build some diffrent enclosures for the mains (also put the HDS tweeters to use). Porting the ca18's should bring out a bit more mid-bass Since the Rl-i is going in the car because of space limitations and I've always wanted an 18, I'm going to replace it with an xxx. I've already started the box for it...here is where I am now :1 inch mdf, undecided wether to flush mount it or not (baffle is going to be double). Still need a couple more braces and a magnet support after seeing how fragile is the basket, more precisely the mounting lip.]
March 13, 200817 yr CA18's and HDS's in a floorstanding tower would be the makings of a very, very nice setup
March 13, 200817 yr Author CA18's and HDS's in a floorstanding tower would be the makings of a very, very nice setup Unfortunately there isn't any room for a pair of floorstanding towers because of the listening position Ignore the "stand", I've replaced that. I'm going to stick with the same general shape, only around 0.7cf ported.Just got the package with the sub amp. Some rather cheap China amp but I'm going to mod it a bit.Got it for 1/2 the price of a new one for people breaking ampsThanks for the comments, more pics coming soon
March 15, 200817 yr Author This is how the box looks now :Should I brace it even more ? There is some carpet between the magnet and the brace and it sits really flush. The amplifier : As soon as I fix it it's getting bigger / more caps for the power supply.
March 17, 200817 yr Author Replaced one of the rezistors in the soft start circuit and the amp turned on. Problem is one of the channels is in protection, but it's a very simple AB amp and I've got the schematic. Just with the silly dmm method I've measured around 450w @ 4 ohms, on one channel. F'ing clip "detectors" turn on waaaaaay too soon.
March 18, 200817 yr Author They might be correct when running it at 2 ohms stereo, but I have to fix one of the channels before I can try I also need measure the voltage drop at high levels and see how I can upgrade the cap bank. Maybe fill up the whole available space with caps...
March 29, 200817 yr Author Fixed the amp. Got around 82v @ 4 ohms bridged, on a 50hz tone, which means around 1.6kw. The dust cap got a bit warn Something seems wrong with the amp's crossover, definately a change in sound (not in a good way) from the cheap separate sub crossover I was using. Looks like I might spend money on a dcx2496.The clip indicators still turn on too soon
June 2, 200817 yr Author Updates : Half the sub amp crapped out on me as soon as I finished the box so now I'm running the xxx with 500w. Plenty to keep me happy I've bought a Rotel pre-amp and I'm using my old rack amp for the mains. I also found some old ply and built a test enclosure for the ca18. It's about 0.7cf, ported at 40hz, far bigger compared to the old sealed one. First impression : nice improvement in midbass, but it's lacking a bit on the vocals. Right now the HDS has only a cap in series and the ca18 is running full-range so I suspect the problems are either some standing waves in the cabinet (correct me if I'm talking BS) or the lack of crossover.
June 2, 200817 yr Author Thanks I'm going to try to cross them higher and see what happens. Probably not going to wind inductors before finals are over.
June 2, 200817 yr Perhaps some sort of L-pad as well...unless you are biamping with adjustable gains.Have you listened to just the tweeter with the cap alone and the CA alone? It will give you some insight as what else to address besides just the slope.
June 2, 200817 yr Author Haven't tried either alone but I will as soon as possible. I forgot to mention I have some sort of L-pad, for ~2dB cut Thanks again for the input.
June 23, 200817 yr Author Turns out they were crossed at 2k They're crossed at 4k right now. Parts for L-pad's (2db, 3db, 4db cut) are on my desk waiting to wire them up. EDIT : I've opened the gains of the sub amp and with a measly 500w I measured it on the TL...for shits and giggles. 127.4dB on the desk
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