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  • Zaph posted results for the 5" and 7" drivers

    The TB 5" underhung looks like a great performer. Distortion spectrum similar to the RS150, but smoother response allowing a higher XO point. So so bass performance, but great midrange.

    Looks like the Illuminator was outshone by the Revelator at $100 less.
    R = h/(2*pi*m*c) and don't you forget it! || Periodic Table as redrawn by Marshall Freerks and Ignatius Schumacher || King Crimson Radio
    Byzantium Project & Build Thread || MiniByzy Build Thread || 3 x Peerless 850439 HDS 3-way || 8" 2-way - RS28A/B&C8BG51

    95% of Climate Models Agree: The Observations Must be Wrong
    "Gravitational systems are the ashes of prior electrical systems.". - Hannes Alfven, Nobel Laureate, Plasma physicist.

  • #2
    Re: Zaph posted results for the 5" and 7" drivers

    Note that Zaph sneaked in the Peerless 830656. He mentioned it as an aside in the blog, in a discussion about lobes. This sub-$25 5.25" driver looks to be a very nice performer if you're willing to give it some volume (15L+). It'll respond with a sub-40Hz F3 (over-excursion occurs at a similarly low frequency). Zaph even states he'd pair (4 actually) it with the Seas DXT tweeter, implying a high regard for it's capabilities.
    - John

    "Injustice anywhere is a threat to justice everywhere." - Dr. M. L. King
    www.BuildTheDream.org

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    • #3
      Re: Zaph posted results for the 5" and 7" drivers

      Originally posted by HareBrained View Post
      Note that Zaph sneaked in the Peerless 830656. He mentioned it as an aside in the blog, in a discussion about lobes. This sub-$25 5.25" driver looks to be a very nice performer if you're willing to give it some volume (15L+). It'll respond with a sub-40Hz F3 (over-excursion occurs at a similarly low frequency). Zaph even states he'd pair (4 actually) it with the Seas DXT tweeter, implying a high regard for it's capabilities.
      3rd harmonic is a bit high in the upper mids though on that Peerless driver. I'd spend a few extra bucks and go with the RS150.
      R = h/(2*pi*m*c) and don't you forget it! || Periodic Table as redrawn by Marshall Freerks and Ignatius Schumacher || King Crimson Radio
      Byzantium Project & Build Thread || MiniByzy Build Thread || 3 x Peerless 850439 HDS 3-way || 8" 2-way - RS28A/B&C8BG51

      95% of Climate Models Agree: The Observations Must be Wrong
      "Gravitational systems are the ashes of prior electrical systems.". - Hannes Alfven, Nobel Laureate, Plasma physicist.

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      • #4
        Re: Zaph posted results for the 5" and 7" drivers

        I'm looking at the SB15NRX's HD measurement and comparing it to the SB17NRX's. For the comparison, note that Zaph's 6.5" HD sweeps were taken with 4 dB lower fundamentals between 300 Hz - 1000 Hz than his 5.5" ones. So, we need to compensate it when comparing 5.5" and 6.5" results.

        http://www.zaphaudio.com/5.5test/SBa...RXC30-8-HD.gif
        http://www.zaphaudio.com/6.5test/SB17NRX35-HD.gif

        Open two windows and compare the above two charts by toggling them. As you can see, their patterns of HD products across the frequencies are very, very similar. No wonder, they share structure and materials. Only the size differs. A noticeable difference occurs below 200 Hz. Even if we consider their different measurement conditions (fundamentals to the 5.5" is 3-4 dB higher than those to the 6.5"), it is clear that the SB17 benefits from its larger Sd to produce lower HDs in lower mids to bass.

        Both of these SB midwoofers are stellar performers in the midrange. But not in the bass and midbass. I'd not choose the SB15 for a full-range 2-way design. In a sealed 2-way, it will work nicely with a subwoofer, crossed by an HT receiver's active HP filter at 80 or 100 Hz. The SB17 will work even better in the same kind of application crossed at 80 Hz.

        -jAy

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        • #5
          Re: Zaph posted results for the 5" and 7" drivers

          The TB 5" underhung looks like a great performer. Distortion spectrum similar to the RS150, but smoother response allowing a higher XO point. So so bass performance, but great midrange.

          Looks like the Illuminator was outshone by the Revelator at $100 less.
          I didn't put any commentary in my blog, so I'll just comment here. Yup, with the Illuminators, I think we're paying for motor machining operations rather than actual increased performance. It is a nice motor, but Scan-Speak really failed to improve on the Revelator's cone and suspension. The Illuminator spider for example is just a plain ribbed model while the Revelator had a unique uneven-rib spider designed reduce suspension non-linearities - and it worked. For those who haven't seen one, I'll attach an image.

          The other three 5.5" woofers are all nice. The TB and SB are good values, the Seas W16NX001 not so much. I'm not placing blame about the US dollar vs Norwegian krone issues, but one thing people should know is that all my value ratings are done through USA eyes. At least in the states, usage of Seas drivers are fading because of their price. Even the Prestige tweeters. I still like and use them myself, but I can see many shying away from the Seas product line.

          If anyone noticed, I finally went through every test group and updated all driver prices. Did anyone notice that the 7" TB underhung went up to $84? I seem to remember it being $55. The non-sale price of the RS180 is now $41. There's a lot of disappointment here. Many of my value ratings have changed a bit. I can honestly say that the driver prices are going to edge quite a few potential new builders out of DIY altogether. I may even start testing and reviewing low priced (-$300pr) commercial speakers because there's a value price point that DIY'ers can't beat.


          Originally posted by HareBrained View Post
          Note that Zaph sneaked in the Peerless 830656. He mentioned it as an aside in the blog, in a discussion about lobes. This sub-$25 5.25" driver looks to be a very nice performer if you're willing to give it some volume (15L+). It'll respond with a sub-40Hz F3 (over-excursion occurs at a similarly low frequency). Zaph even states he'd pair (4 actually) it with the Seas DXT tweeter, implying a high regard for it's capabilities.
          To clarify that a bit, I would only consider using that Peerless for the MMTMM design I discussed because of it's specific abilities. The smoother top end response and minimal HD peaking is the notable characteristic I would need for that directivity controlled design, while the higher non-linear distortion becomes a non-issue when I'm using 4 per side. As a bonus, a surface mount frame sure would be nice when there's 8 woofers to mount. I don't think I'd use the driver in a 2-way however, particularly with the availability of the cheaper and better performing MCM 55-3870. Well, as far as availability, it went out of stock shortly after I posted the ZMV5 but they should have more in about a month.
          Attached Files

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          • #6
            Re: Zaph posted results for the 5" and 7" drivers

            Originally posted by jkrutke View Post
            If anyone noticed, I finally went through every test group and updated all driver prices. Did anyone notice that the 7" TB underhung went up to $84? I seem to remember it being $55. The non-sale price of the RS180 is now $41. There's a lot of disappointment here. Many of my value ratings have changed a bit. I can honestly say that the driver prices are going to edge quite a few potential new builders out of DIY altogether. I may even start testing and reviewing low priced (-$300pr) commercial speakers because there's a value price point that DIY'ers can't beat.
            I did notice the Tang Band price increase John, the price went up right after you posted your measurements. Coincidence? I hope so, it would be a shame if PE or TB is using your site as leverage to increase their prices.

            The SB17NRX went from $53 to $61 right after your results were posted as well, but that is less dramatic than the TB and is a smaller pill to swallow.

            I think my next project will be a very high performance project. I really like the ZMV5's and they definitely occupy a unique place on the value scale. If I'm going to spend hours upon hours on another project it's going to be something that has performance that would be otherwise more expensive than I could afford to buy at retail cost.

            -David

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            • #7
              Re: Zaph posted results for the 5" and 7" drivers

              Originally posted by depthsounder View Post
              I did notice the Tang Band price increase John, the price went up right after you posted your measurements. Coincidence? I hope so, it would be a shame if PE or TB is using your site as leverage to increase their prices.

              The SB17NRX went from $53 to $61 right after your results were posted as well, but that is less dramatic than the TB and is a smaller pill to swallow.
              Oops, I missed the SB17. I think since it was a fairly recent test earlier this year, I figured the price would still be ok. Nope.

              I doubt if PE or MAD increase prices based on my results. But what I suspect happens is that people see my results and there is a buying frenzy, depleting stock. The vendor goes to reorder, gets a new price quote and wham, our new prices reflect their new cost. In this turbulent economy, prices for manufacturing are changing all the time, mostly based on steel costs. I work in manufacturing, and when we give a customer a price quote, we make it expire in a few days because of ever increasing costs. If we even gave a price quote a lifespan of a month, we'd lose our *** on it.

              I hope MCM's 55-3870 doesn't go up. Another unique pricing condition: if you see a driver that's not going up in price, it probably means they aren't selling. There are some slow movers that haven't changed since 2005.

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              • #8
                No, no. They're doing us a favor.

                Here's the deal. Without these necessary market adjustments, we would have approached the awkward condition where the primary series inductor in the typical two way cost more than the woofer or tweeter.

                With the increase in driver prices, the natural gap between the cost of an inductor and a driver, um, balance, has been restored. :D

                Note to PE and MAD. Copper prices have fallen in half this past year. Can we get a break on inductors...?
                audioheuristics isn't around right now...

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                • #9
                  ^^^ Don't Count On It...

                  :rolleyes:

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                  • #10
                    Re: No, no. They're doing us a favor.

                    Originally posted by markk View Post
                    Note to PE and MAD. Copper prices have fallen in half this past year. Can we get a break on inductors...?
                    Funny how companies don't like to lower prices when their costs go down, only increase when their costs go up :(

                    I did see one place selling copper wire at $5.34 / LB (minimum 10 lbs) with reasonable shipping costs, that's a nice change from the $8 - $10 price I've been seeing on Ebay lately!

                    Note: seems like too many people assume that speakers made with "cheap" drivers can't sound better than "High End" speakers. "You get what you pay for" is a statement that I think is as often untrue, as it is true, when it comes to speakers. Too often people let (unconsciously, mostly) bias towards more expensive goods convince them that $$$x sounds better than $y, when that might not have been the case had they done a blind test.

                    Though, it does seem to me, that it is hard to get good bass cheaply - you need power and power handling (among other things)...
                    "...this is not a subwoofer" - Jeff Bagby ;)

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                    • #11
                      SB Acoutsics

                      What are folks impressions of the SB acoustics speakers? Anyone use the 5.5 incher?

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                      • #12
                        Re: Zaph posted results for the 5" and 7" drivers

                        Hey all, I have Le(x) plots available for all of the recently tested woofers and a few of the older ones. I believe this is an important measurement to supplement my other testing and I'll be collecting this data more in the future. I wish I'd been collecting this data from the beginning, but I'm still learning myself and only realized the importance of it in the short time since I tried this measurement about a year ago.

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                        • #13
                          Re: Zaph posted results for the 5" and 7" drivers

                          Originally posted by jkrutke View Post
                          Hey all, I have Le(x) plots available for all of the recently tested woofers and a few of the older ones. I believe this is an important measurement to supplement my other testing and I'll be collecting this data more in the future. I wish I'd been collecting this data from the beginning, but I'm still learning myself and only realized the importance of it in the short time since I tried this measurement about a year ago.
                          What frequency(ies) are you using for the test, if I may ask? I have done some experimentation on this myself as I was developing my auto-zobel feature in PCD because I found that the standard view of inductance was woefully weak in giving me something to work with that produced good results. However, I came up with a way of analyzing the imported impedance data and doing a mathematical curve-fit that resulted in a very nice flat impedance when the zobel values were calculated. These values, however, were different than the standard formula gave, but I also found that they worked well if I measured inductance at a considerably higher frequency than is normally used. (I should write a paper on this one.)

                          Jeff B.
                          Last edited by Jeff B.; 12-23-2008, 03:28 PM.
                          Click here for Jeff Bagby's Loudspeaker Design Software

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                          • #14
                            Re: Zaph posted results for the 5" and 7" drivers

                            Jeff I beleive John just runs an impedance measurement using an MLS signal for this. So full frequency. Good to see John is publishing this now. I've been doing it ever since I read about it in your blog. Now if we could just talk you into using Linkwitz's excursion measurer you could start doing Klippel's performance based method Actually it should be pretty easy with the spectrum analyzer, you would just need a spreadsheet built to enter in HD and IMD amplitudes and quickly calculate the performance.

                            I'd be interested to see teh Zobel calculator you come up with. Soundeasy uses curve fitting for Le but doesn't use it for the Zobel calculator, it just uses the resulting Le value. Usually pretty good job though. The curve fitting range default is 2-5khz. I adjust the lower value for better fit but have never found raisng the upper 5khz value to improve accuracy. What range are you working with?
                            ~Brandon 8O
                            Please donate to my Waveguides for CNC and 3D Printing Project!!
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                            DriverVault
                            Soma Sonus

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                            • #15
                              Re: Zaph posted results for the 5" and 7" drivers

                              BTW John do you think it would be better to measure at the xmax of a respective driver, or measure at an excursion that is typical of xmax for a given size driver group? I ended up using this latter method so the results would be standarized: impedance at a given SPL.

                              Considering how crude this method is, and it's use in a comparative survey, this seemed like a reasonable choice. Thoughts?

                              How did you measure excursion? Mine were just eyeballed, since i just wanted a rough idea of performance between drivers.
                              ~Brandon 8O
                              Please donate to my Waveguides for CNC and 3D Printing Project!!
                              Please donate to my Monster Box Construction Methods Project!!
                              DriverVault
                              Soma Sonus

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