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  • #16
    Originally posted by Sydney View Post

    Sort of...
    Both are Active in that they manipulate audio at signal level using electronics.
    DSP is another approach to signal conditioning. As it involves conversion to a Digital form of data, it opens up many additional capabilities and possibilities beyond Analog and simply impractical/unattainable using a passive approach.
    Well, I guess I was thinking if it wasn't digital, it must be analog. Your definition of 'at signal level' is much more precise and correct, for sure. At any rate, I would say that timing is another critical thing common to home and PA sound. PA sound just extends the utilization.

    I worked in electronics for 30 years, but it sounds like you have a LOT of experience in audio and PA. Would you have any specific advice or recommendations for building a bigger Hi-Fi?

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    • #17
      Honestly, It seems like you already are on top of things....
      1st off
      My M.O. is primarily quantitative - ie Size of Room, SPL desired @ various frequency are parts of Acoustic data of requirements.
      Are you familiar with this?:
      http://www.linkwitzlab.com/SPL%20nomographs.htm
      "Not a Speaker Designer - Not even on the Internet"
      “Pride is your greatest enemy, humility is your greatest friend.”
      "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

      Comment


      • #18
        Originally posted by Sydney View Post
        Honestly, It seems like you already are on top of things....
        Well, I have my way of doing things, but I am eager to hear of others.
        Originally posted by Sydney View Post
        My M.O. is primarily quantitative - ie Size of Room, SPL desired @ various frequency are parts of Acoustic data of requirements.
        Yeaaah, that's not really in my wheel house. I start out with the question of 'How big can I make it?' I figured I could get about 2000 useable watts out of a 20 amp wall outlet. Using that as a starting point, I then looked at driver efficiencies - what kind of bang for my wattage buck could I get? It kind of evolved from there.

        If it's too loud, well, I don't always have to have it up all the way, do I?

        Originally posted by Sydney View Post
        Bookmarked. That is GREAT information to have all in one place! That is exactly the 'bass wall' I've been running into, and why I have that massive (which isn't big enough) 18 inch sub crossed over down at 60 Hz. That sub is usually doing practically nothing - but when you need it, it sure is nice to have some headroom down low.

        I know what you mean about concert bass. I was at a concert one time (Dave Matthews, I believe) and a drum solo started. He had a double-peddle bass, which he hit for a prolonged fast roll - and it just faded right out, and you could tell that even though he had rows of massive subs, his amps just ran out of gas. Very disappointing. That's another thing I've tried to avoid - another pitfall.

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        • #19
          http://www.linkwitzlab.com/Fitz/acoustics-mechanics.htm
          "Not a Speaker Designer - Not even on the Internet"
          “Pride is your greatest enemy, humility is your greatest friend.”
          "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

          Comment


          • #20
            In 1976 I saw this article :
            http://www.burwenaudio.com/Sound_System.html
            "Not a Speaker Designer - Not even on the Internet"
            “Pride is your greatest enemy, humility is your greatest friend.”
            "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

            Comment


            • #21
              That said, I looked carefully at X-max in sims when choosing drivers and crossover points. For me, it really came down to trying to 'fill up' my listening space. No problem with the top end - but I found out the hard way it takes a lot of power and capacity to make real bass.

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              • #22
                Excellent information again! I feel I've already learned some of it, but will give it a thorough reading soon.

                Comment


                • #23
                  Originally posted by Sydney View Post
                  Awesome! My next system, however, will essentially be a large console, fitting everything, including subs, into one cabinet. I'm sure it' won't approach 'the ultimate' system in sound quality, but I don't feel any sonic negatives will outweigh the integration into the home aspect.

                  Consoles are coming back, actually.

                  Comment


                  • #24
                    RE: Xmax
                    Knowing that this represents a 10% distortion figure - I set my "ceiling" below that ( at least -6db ). This is also a "habit" from running live sound, as it lower distortion and lessens power compression and improves reliability
                    Typically with Live Sound - the drivers are high sensitivity with lower displacement.
                    btw: Though I degree in Digital Electronics - I keep my hands in Live/Performance Sound but decided long ago that I didn't want to be a serious Sound Provider with a huge investment in gear, etc.
                    "Not a Speaker Designer - Not even on the Internet"
                    “Pride is your greatest enemy, humility is your greatest friend.”
                    "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

                    Comment


                    • #25
                      Originally posted by Sydney View Post
                      RE: Xmax
                      Knowing that this represents a 10% distortion figure - I set my "ceiling" below that ( at least -6db ). This is also a "habit" from running live sound, as it lower distortion and lessens power compression and improves reliability
                      Typically with Live Sound - the drivers are high sensitivity with lower displacement.
                      btw: Though I degree in Digital Electronics - I keep my hands in Live/Performance Sound but decided long ago that I didn't want to be a serious Sound Provider with a huge investment in gear, etc.
                      My experience as well. After extended listening I have set the crossover points on both the mid and tweeter higher. The 4015LF with 9mm Xmax doesn't have a problem. It's really a nice driver.

                      I don't actually have a degree - I got my electronics training in the military. I got some digital training (in the '80s), but my first duty station was actually maintaining an all tube radar! Honestly though, I loved it. Naturally, I also have a fair collection of classic '50s Hi-Fi components - Fisher and Bogen mostly.

                      Comment


                      • #26
                        The man who created the concept of audio delay ( W.B. Snow ) did so around 1937 ( I believe), and in 1957 Heathkit came up with X0-1 Vacuum Tube Active Crossover,,,so it often takes time for concepts to mature and catch on.
                        Anyway - With the target Acoustic demands defined - the ElectroMechanics ( Amplifier/Speaker) side is addressed
                        https://www.crownaudio.com/en/tools/calculators
                        see Amplifier Power Required here:
                        https://www.crownaudio.com/how-much-amplifier-power
                        "Not a Speaker Designer - Not even on the Internet"
                        “Pride is your greatest enemy, humility is your greatest friend.”
                        "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

                        Comment


                        • #27
                          Originally posted by Sydney View Post
                          The man who created the concept of audio delay ( W.B. Snow ) did so around 1937 ( I believe), and in 1957 Heathkit came up with X0-1 Vacuum Tube Active Crossover,,,so it often takes time for concepts to mature and catch on.
                          Anyway - With the target Acoustic demands defined - the ElectroMechanics ( Amplifier/Speaker) side is addressed
                          https://www.crownaudio.com/en/tools/calculators
                          see Amplifier Power Required here:
                          https://www.crownaudio.com/how-much-amplifier-power
                          Not sure who invented audio delay, but I am very familiar with 50's consumer electronics, and other than innate filter group delay, the XO-1 didn't have any provision for delay, only frequency and level, as indicated on the front panel, link below. I would be interested to find out just when delay became prevalent, and how they accomplish it in an analog system.

                          I am checking out the links you have given against my system and the results are interesting.

                          In the first one, for amplifier power required, I input listener 5 meters from the source, for a 110db SPL at the listener position, for a speaker with a 94db sensitivity (which mine has), with 3db headroom, and the calculated required amplifier power is: 1986 watts. Spot on!

                          The second link explains this very well, and though the PA math is pretty new to me it totally squares with my experience.

                          I rarely listen to it that loud - but sometimes Beasty Boys or Hendrix or Flaming Lips gets away from me, and I just have to crank it!

                          Anyway, thanks for the links. I will be checking my system further as I study the links you have provided. Great info!

                          Edit: Adding the link manually as the inserted link doesn't want to work, for whatever reason.


                          https://img.usaudiomart.com/uploads/...to_deliver.jpg

                          Comment


                          • #28
                            Originally posted by LafeEric View Post
                            ... I would be interested to find out just when delay became prevalent, and how they accomplish it in an analog system....
                            In 1969 F. Sangster and K. Teer of the Philips Research Labs invented the Bucket-Brigade Device (BBD). This device operates as delay by transferring charge packets from one transistor/capacitor cell to another.
                            I don't recall exactly when I started seeing simple delay integrated into rack units, roughly late 70s early 80s. By mid 80s Lexicon units were common.
                            btw: My home system drivers run approx 94db/1wt as well - Not as high as the more sensitive Pro Sound drivers, but still roughly 6db more sensitive than a typical home speaker.
                            .
                            "Not a Speaker Designer - Not even on the Internet"
                            “Pride is your greatest enemy, humility is your greatest friend.”
                            "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter."

                            Comment


                            • #29
                              A large personal system.

                              Titan-630 XL-XXL Dual 15's and waveguide 13.5 cubic ft. cabinets tuned @25hz. - AVS Forum | Home Theater Discussions And Reviews

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                              • #30
                                It's funny how perceptions develope...i gave up on "PA" gear at home roughly 20+ years ago after trying some random things. Fast forward to about 2-3 years ago, my system now cosists of all JBL gear. Mains are dual 2226Hs, 2251J and 2447H with SL diaphragms. Center is a 261F under another 2447H-SL. All 3 2447s are mounted on 2384 waveguides from the CinemaArray line. Amps are all Crown Com-Techs and Micro-Techs. Processing is handled by a BiAmp TesiraServer. The results are as "Hi-Fi" as anything I've heard prior, and then some. I don't think I'll ever go back to "low" efficiency drivers in the main system.

                                There are some things I'd like to change, however, but it's not any of the above except for the center channel woofer. The 261F comes in the EON510 and it isn't quite on par with the 2251J. The other is my subs. Currently using 3x SI HT18s for movies only, not needed for music, nor do they sound good for it. Eventually I'll likely replace those with 2242Hs, or something along those lines.

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