Announcement

Collapse
No announcement yet.

Hardest driver you've work with?

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    Originally posted by bcodemz View Post

    No need for giant speakers. A lot of "rules" don't apply when you have DSP! I can simply shape the bass response to flat. I can easily get away with a 1 cu ft enclosure or smaller instead of 4 cu ft., tune it deep, boost it flat, and get *more* bass extension and the same output as a much larger cabinet. These woofers don't have enough Xmax for power handling to be an issue from DSP bass boost.

    2-4 cu ft isn't giant in my book. Things like Klipsch Cornwalls are the starting of giant. Then again I have a 4.5 cu ft and a 12 cu ft sub enclosure in my room.... But the DSP is more for crossing low where a passive XO would need massive inductors... And boost eats headroom. Use a decent wideband/fullrange mid and cross the woofers low and the tweeters high.

    I still think a folded TL with dsp to fix the ripple would be awesome though.

    Comment


    • #32
      Originally posted by make_some_noise View Post


      2-4 cu ft isn't giant in my book. Things like Klipsch Cornwalls are the starting of giant. Then again I have a 4.5 cu ft and a 12 cu ft sub enclosure in my room.... But the DSP is more for crossing low where a passive XO would need massive inductors... And boost eats headroom. Use a decent wideband/fullrange mid and cross the woofers low and the tweeters high.

      I still think a folded TL with dsp to fix the ripple would be awesome though.
      You know... the biggest speaker I've built is the one I'm working on right now, and it is ............. 0.15 cu ft. A 2 cu ft speaker is like Shaquille O'Neal sized to me.

      There is a way to boost without eating headroom. My last speaker needed 13dB of boost, and the current speaker I'm working on needs around 17dB! It is also capable of playing ~110dB peaks. Can't do that if I have to give up 17dB of headroom for the boost.

      Comment


      • #33
        Originally posted by jhollander View Post
        So a $2 piezo tweeter is in contention? Seriously though the DSP is not going to fix distortion issues so why not do something that makes sense wrt to the cost of the DSP?
        Its nor a $2 piezo, its a $6 cone. Sheesh. Lol

        I would dig up the distortion measurements, which are very low on it, as good as any $20-40 tweet, anyway, but if his souldtion, or "challange" is to EQ a woofer to +17dB in a .15cf cab, then I am unsurw how serious this project is since he seems to want to create as many prolems as he solves.
        .

        Comment


        • #34
          Well, it is my belief that the XT25 is capable of playing below 2500 - I crossed it at 2100 in the MTM I brought to Iowa in 2012. I also believe it can be crossed lower yet, as low as 1900 in certain applications, but requires a little attention to detail above and beyond. That, to me, makes it a difficult driver to work with.

          Most of the aluminum RS180 designs I have heard seem to indicate it is much more difficult to work with than indicated.

          I do agree with Mr. Hollander - if non-linear distortion issues are what make the driver difficult, not much we can do with them regardless of what kind of network we use. Linear distortion issues are what EQ is for, however. Passive or active or DSP - whatever it takes, I guess.

          Paul's comment about notching a specific region in the Silver Flute holds true for a lot of drivers in my experience. I think in our quest for minimal parts counts and/or focusing on crossover region and relative tweeter level that we sometimes forget a wide hump across an octave that is seemingly benign based on the +/-3db (or any +/- you want to use) can definitely alter tonal balance. That region sucks on quite a few speakers, to be honest. On typical speakers with baffles in the 6-9" range and typical 1500-2500 crossover points, issues in that range are exacerbated by baffle step loss, baffle signature, and added reactance from the crossover itself. I have taken to assuming a notch will probably be needed on the woofer below the crossover point - the results are worth the added cost IMO. This issue is particularly pronounced in smaller speakers, but present in most. If the driver has inherent non-linear distortion in the range below the crossover point - it will really start shouting at you. The SB Acoustics 5" I used in Vermillion exhibits pretty mediocre sound below the crossover point absent some flattening around 1K. I have heard similar statements on Revelators.

          Maybe the reasons we consider some drivers difficult to work with is not much more than the natural impression we get of throwing "good money after bad"
          Don't listen to me - I have not sold any $150,000 speakers.

          Comment


          • #35
            Originally posted by bcodemz View Post

            You know... the biggest speaker I've built is the one I'm working on right now, and it is ............. 0.15 cu ft. A 2 cu ft speaker is like Shaquille O'Neal sized to me.

            There is a way to boost without eating headroom. My last speaker needed 13dB of boost, and the current speaker I'm working on needs around 17dB! It is also capable of playing ~110dB peaks. Can't do that if I have to give up 17dB of headroom for the boost.
            Different strokes for different folks I suppose. I can tell you that personally I can tell the difference between a system with a ton of boost vs. one that achieves the same output in a more natural manner even if they measure very similar.

            I am all about bending and even breaking the rules. But there are limits to physics. Sure you're giving up headroom by sucking the power supply of the amp dry just to take care of the boost down low. 17dB is an insane amount of boost in the bass section and unless you have some 5kW amp with a power supply big enough to be a boat anchor for a yacht... You'll be clipping the amp before you are producing any serious continuous average volume with most hi-fi type drivers. 110dB peak isn't really that much. How about 110dB average? That way when bass players are hitting low E's you feel it like the bass was in the room with you, or in an electronica track the bass actually rattles stuff in the room. While some may say that 110db is very loud, many rock concerts average 120db which is far louder than 110dB. I find that between 100-110db is a good compromise between the engagement and visceral appeal vs. blowing your ears out at a concert. With that much boost you're likely approaching thermal meltdown of a small driver's voicecoil with the volume barely turned up especially if you are pushing very far past xmax.

            Maybe it might be ok if you only listen to soft jazz or something, but personally I listen to at least something of about every genre. As much as I admire trying to squeeze the most our of a small system and near field listening... It's not the same as emotional engagement most receive from a live performance, or something that mimics a live performance. No different than in the car world, "there is no replacement for displacement" Even with larger speakers, a sub of decent proportions is often needed to produce life like effects (or more) and .15 cu ft is tiny for a speaker let alone a sub. JMHO

            But at the same time DIY is great because people with different preferences can get what they want which you often cannot get with a commercially produced product. So if you are producing what you want... Then I salute you even if it isn't my cup of tea.

            Comment


            • #36
              Originally posted by johnnyrichards View Post

              Paul's comment about notching a specific region in the Silver Flute holds true for a lot of drivers in my experience. I think in our quest for minimal parts counts and/or focusing on crossover region and relative tweeter level that we sometimes forget a wide hump across an octave that is seemingly benign based on the +/-3db (or any +/- you want to use) can definitely alter tonal balance. That region sucks on quite a few speakers, to be honest. On typical speakers with baffles in the 6-9" range and typical 1500-2500 crossover points, issues in that range are exacerbated by baffle step loss, baffle signature, and added reactance from the crossover itself. I have taken to assuming a notch will probably be needed on the woofer below the crossover point - the results are worth the added cost IMO. This issue is particularly pronounced in smaller speakers, but present in most. If the driver has inherent non-linear distortion in the range below the crossover point - it will really start shouting at you. The SB Acoustics 5" I used in Vermillion exhibits pretty mediocre sound below the crossover point absent some flattening around 1K. I have heard similar statements on Revelators.

              Maybe the reasons we consider some drivers difficult to work with is not much more than the natural impression we get of throwing "good money after bad"
              Good point. And to be honest sometimes looking at a measurement it is hard to tell what is going on if everything looks relatively flat. Once you've built a crossover and are listening to it to fine tune it and you have these problems... I've found that after a fair bit of auditioning the speaker, one can take a signal generator and turn it up in frequency until you hear the pitch that sounds about the same as where things sound too strong. Almost like tuning an instrument. Once you've identified the frequency or one close to the problem area, you can alter the EQ or play with notches of various widths in that area and start to zero in on a fix..

              As much as people dog 3-way speakers due to cost and part count, it is often easier to solve these issues with a 3-way than a 2-way since you have more drivers in narrower bandwidths to massage the response of.

              Comment


              • #37
                mzisserson and @​make_some_noise

                I'm a person that likes to have the cake and eat it too. See post 30 in this thread where I explain how I can boost without cutting headroom.

                Comment


                • #38
                  Originally posted by bcodemz View Post

                  Haha, I don't have the skills to do a good passive crossover, so I hide behind a DSP and a bunch of amps!



                  You have a perfectly valid point, and I think your analysis is spot on. Part of it is indeed to demonstrate the benefits of DSP.

                  After taking on an enormously challenging and complicated cost no object project, I want to use some very low cost drivers and see how much performance I can possibly squeeze out of low cost drivers with advanced DSP and how close in performance I can get to that cost no object speaker. I'm looking for drivers that might be fantastic but overlooked due to the cost and complexity to build a crossover to get the best out of them. The real challenge is to make a low cost speaker sound great.
                  You might want to consider some of the prosound woofers out there. Although most of them weren't cheap, I've looked at a lot of Faital and B&C drivers that seem to have low distortion, low Le, and decent Xmax. The probelm has been that almost all of them either have a high fs or a very low Qts, which makes them very difficult to get good bass extension. The ones that have better bass obviously trade some efficiency. To me, this makes the higher efficiency units a good candidate for DSP. And as others have mentioned, many of the prosound drivers have a little lumpier frequency response that could also benefit from some DSP.

                  -Kerry

                  www.pursuitofperfectsound.com

                  Comment


                  • #39
                    Originally posted by bcodemz View Post
                    After I finish my current speaker, I will want another challenge. This time, I'm thinking of using a normally challenging driver, and get it working well with DSP.

                    So I'm curious, what are the hardest drivers you've know or worked with, and why?

                    EDIT: OK maybe not necessarily the hardest, but simply tough drivers to work with, and if they sound fantastic only after their problems are dealt with, even better!
                    Well, assuming you are really looking for a nice driver, as opposed to trying to prove something, I'd offer up this 5.25" driver for midrange duty. I've done so passively a few times, and like it a lot. Sometimes the x-over part count for the whole speaker gets rather high.
                    http://www.parts-express.com/peerles...ofer--264-1074 Maybe with this woofer. http://www.parts-express.com/dayton-audio-ls10-44-10-low-profile-subwoofer-dual-4-ohm--295-251#!

                    Comment


                    • #40
                      Originally posted by Navy Guy View Post

                      You might want to consider some of the prosound woofers out there. Although most of them weren't cheap, I've looked at a lot of Faital and B&C drivers that seem to have low distortion, low Le, and decent Xmax. The probelm has been that almost all of them either have a high fs or a very low Qts, which makes them very difficult to get good bass extension. The ones that have better bass obviously trade some efficiency.
                      Kappalites are pretty good with efficiency and extension. There are a couple others but I can't remember their models. One was a B&C and the other was a faital.

                      Comment


                      • #41
                        Originally posted by Wolf View Post
                        In a 2-way...
                        HiVi M8A/M8N was a chore! +15dB peak at 2kHz breakup.
                        BG Neo3 was a bit of fun too. Sssibilant or no-air, your choice.
                        HiVi M4N was fun too. I used the BSC signature to better the response, and still needed a notch. Then the High-Qts makes for an interesting box alignment.

                        I think if you want a challenge, try the somewhat forbidden combo of the RS180-8 and the XT25TG30. Nobody has made this work and published it thus far to the best of my knowledge. It has been a talked about combo for ages.

                        Have fun!
                        Wolf
                        Wolf have you had a go at it and decided it was not worth the time investment RS180 and XT25. Also I have heard you say you like Hi-Vi M8a & M8n but hard to
                        deal with. In a 3-way with the M8a, which is the way I am headed TMWW at the lower X-over I hope the issues are reduced.

                        Comment


                        • #42
                          Originally posted by Squidspeak View Post
                          Wolf have you had a go at it and decided it was not worth the time investment RS180 and XT25. Also I have heard you say you like Hi-Vi M8a & M8n but hard to
                          deal with. In a 3-way with the M8a, which is the way I am headed TMWW at the lower X-over I hope the issues are reduced.
                          Not Wolf But I have used the m8a in the bottom of a 3way (with Wolfs help on the whole speaker). It is pretty easy to deal with as you are well below breakup.

                          Comment


                          • #43
                            Originally posted by killa View Post

                            Not Wolf But I have used the m8a in the bottom of a 3way (with Wolfs help on the whole speaker). It is pretty easy to deal with as you are well below breakup.
                            ​Thanks Killa, I chose these woofs along time ago so I am confident they will serve me well. I also have full confidence in the forum member that will be doing the X-over
                            design.

                            Comment


                            • #44
                              I agree with killa. I still notch the breakup because of magnitude, but it is easier. I first used it in the MAX, and had a strong uphill road to tame that beast and xover high enough to meet the tweeter. I did like it a lot, and bought a quad of the M8A for an upcoming project.

                              And no-
                              I've not tried the RS180/XT25 combo myself.

                              Later,
                              Wolf
                              "Wolf, you shall now be known as "King of the Zip ties." -Pete00t
                              "Wolf and speakers equivalent to Picasso and 'Blue'" -dantheman
                              "He is a true ambassador for this forum and speaker DIY in general." -Ed Froste
                              "We're all in this together, so keep your stick on the ice!" - Red Green aka Steve Smith

                              *InDIYana event website*

                              Photobucket pages:
                              http://photobucket.com/Wolf-Speakers_and_more

                              My blog/writeups/thoughts here at PE:
                              http://techtalk.parts-express.com/blog.php?u=4102

                              Comment


                              • #45
                                Originally posted by Wolf View Post
                                I did like it a lot, and bought a quad of the M8A for an upcoming project.
                                Wolf
                                Is it me or is there something about the way the hivis do bass? To me the two I have used (m8a and m12) seemed to have what I would describe as really good motor control which gives a lot of accuracy to the lower region. Wish I could describe it better.

                                Comment

                                Working...
                                X