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billybobg

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Posts posted by billybobg

  1. Olorin,

    Frankly, I didn't take your question as criticism. Only curiousity. I think that's what keeps forums going. I've shared what I know and questions are to be expected. I'm just being honest. Fact is, I've got the math skills to figure out, just didn't think that it would affect the LF enough to matter. As IKF stated, we live in the mid regions. The LF tends to be geared towards efficiency and again, this seems totally up to the job. Anyway, I really do appreciate the comments I've received and I do like playing around. It would have been a real bummer had I, like you said, found it totally unacceptable after several weekends of work.

    bob

  2. At the risk of criticism from all sides I'll confess my sins. I kept the 3" and the sides of the straight part of the base bin (about 7"). The slope at the rear did change and I had it run from the opening of the base bin to the side of the base bin. The flare is what it is. I can't quote the source, but in researching I found that the extra flare at the front would not affect the response as much as keeping the volume of the base bin consistant with the original. I'm willing to accept inputs (stone throwing) should anything not bare out, but I'm very satisfied with what I hear.YMMV. If I had the equipment, I would make measurements, Now that you've mentioned it, I probably should do the calcs and see if anything I did is fatal.

  3. IndyKipschFan,

    Ya hafta wait until I get home. Unfortunately, I didn't do build photos, but then there are plenty of those. I do have a photo of the three fronts which I'll post when I get on my home 'puter. I have some sketchy (as in questionable in accuracy) Sketchup drawings and a calc sheet on the inner dimensions of the base bin if anybody is interested. This includes calcs on the angle of the W front.

    bob

  4. I built what I call a squatting Lascala. I picked up a used AA Crossover, K-77, and K-55 driver. I bought a woofer from Crites and a 401 Horn from Klipsch. I was able to reduce the heighth down to 26 - 27 inches which will work for the screen I'm building (115"). I made the woofer box wider to keep the volume near the production model and mounted the K-77 to the side of the 401. The heighth of the base bin is constrained by the 15" woofer. I made it 16". I also took some heighth off the HF section with mounting the K-77 to the side. There is room for a second tweeter, but the advice I got from the forum is that there could be comb filtering effects with having two tweeters so close. I can't tell the difference in sound from my ca. 1981 LaScalas and this new build and the trio is very impressive with any movie, though I've only watch some samples so far on an older tube tv.

    bob

  5. Dave

    Okay, I took a GOOD look at my LS last night. Quite frankly, the grain of the veneer is VERY random. It looks a lot like it came from the sap wood of the tree and therefore is really not very good grain. I have to backtrack and confess that, if anything, all of the grain of the speaker is running N/S. [:$] Oh, well. Serves me right for commenting based on my feeble memory . My only saving grace is that I have looked at a lot of speaker updates that matched the grain pattern going around the speaker. Some looked good, some not. On my squatting LS for my center channel, I attempted to match as best as I could. Turned out okay, but not a show piece.

    Anyway, your work definitely worth watching and should be superior..

    bob

  6. I don't know about that generalizing. A voltage source with an output resistor is a current source.

    Okay, I'm an idiot trying to answer this.

    Ohms Law: V= I x R. Power out is P= VxI. Remember that the current source is a voltage source with a resistor in line. For the whole circuit then Ohms Law looks like V= Ix(R1 +RL) R1 equal to limiting resistor and RL equal to the load such as an 8Ohm speaker. If R1 is large (10 times or more) compared to RL, then mathmatically, RL can be ignored I=V/R. This means that the current delivered is independant of RL (as long as RL stays low).

    For a voltage source, its sort of the opposite. In the real world the voltage source is low impedance (Internal.25 ohms or so) so the majority of the voltage drops across the load and therefore the load pretty much sees what voltage is being produced at the source. Think of a car battery and that the voltage is independant from the load.

    Put both of these in the power equation P=VxI and sustituting V=IxR, you get P= (IxI)xR (Current Source), or substitute I=V/R and you get P=(VxV)/R (Voltage Source)

    What does this mean? My impression is that it indicates how the output power is calculated. A current source can be limited to protect the load with the source resistor. With a voltage source, a diode could limit the voltage that is allowed across a load.

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