07-24-2017 Post does not mapped to Knowledge Tree Audiogerhard Posts 1 Joined on 07-24-2017 Post #: 61 Post ID: 23338 Reply to: 22557 Crossover hornfabrik Hi I read about your very fine hornsystem on Romy´s homepage. I started now a own Hornproject and I see your crossover from “Hornfabrik”. You have so right that a good crossover is also a key for a very good hornsystem. I´m so interested on the values from the crossover. Is it possible that you send me the values from your crossover. Kindly regards Gerhard

07-24-2017 Post does not mapped to Knowledge Tree kodomo Posts 69 Joined on 06-20-2015 Post #: 62 Post ID: 23339 Reply to: 23338 Which values? Which values are you after? If its the crossover points, here they are, they ay be indicative for you; dual Tad1601b's in 298lt br boxes - open on bottom to 120 Hz, in a range 90 to 150 Hz ~12 dB (three different settings can be chosen, according to room response) cf110hz tractrix - supravox 285-2000 modified - 100Hz (effective 150Hz) - 600Hz (effective 500Hz) - 6 dB cf200hz tractrix - radian 850 - 500Hz - 5000Hz - 6 dB cf1400 JMLC - radian 475be - 4500Hz - 12000Hz (effective 8000Hz) 6 dB fostex t500amkII 9000 Hz (effective 7000Hz) 6 dB However, unless every single component is exactly the same with mine, my crossover wont work for you...

07-25-2017 Post does not mapped to Knowledge Tree kodomo Posts 69 Joined on 06-20-2015 Post #: 63 Post ID: 23340 Reply to: 23339 Impedance correction Keep in mind that my crossovers are not just 6db filters. There is an impedance correction network, suited to these exact drivers in these horns. Unless this correction is there, the first order filters can not work against the rising or falling impedances.  Only after achieving flat responses from these drivers in their respective horns within their chosen ranges, they are filtered with 6db. That is also the reason that my crossovers are unique to my system. If I make a change, I will also need to change the corresponding part in my crossovers.

05-16-2018 Post does not mapped to Knowledge Tree kodomo Posts 69 Joined on 06-20-2015 Post #: 64 Post ID: 24855 Reply to: 21722 Update on room and new measurements I just wanted to make an update. I have since rebuilt our main room and am very happy about it. Having a very good and homogenous decay (within 0,05ms) for the whole audio band really turns the listening experience in to something else. Total clarity from bass to upper end. Great transient response, a very relaxed sound without loosing any of the good qualities like dynamics and detail. The front wall is made up of binary diffusors and about 30cms worth of absorbtion behind it. The center is made up of a vertical moss garden. Then there are the moveable absorptive panels on top of my vinyl cabinets. There are also basstraps on the rest of the wall to ceiling corners. Total absorption is calculated and then applied, it resulted in great response. Having a symmetry is also great after having the room open on one end at my old setup. The general stereo image is better with symmetrical setup. All in all, I am very happy about the new room.

05-16-2018 Post does not mapped to Knowledge Tree Romy the Cat Boston, MA Posts 10,184 Joined on 05-28-2004 Post #: 65 Post ID: 24857 Reply to: 24855 Very nice. So, basically you built a wall on the right side, separating the listening section from whatever it is behind the wall. A bold move. As the room become slightly smaller and you lost some time for bass dissipation you might try to drop the slope at your bass section crossover. I do not know where you cross (too lazy to look in the thread), let pretend that it is second order 115Hz. Try to switch to 70-80Hz first order and see how you feel. In smaller room this move I feel it works well. You might feel that it would eat some transients, then ide the loading a little (in case you drive the bass section by tube SET). In many cases this will mask out the shorter room reverberation time.    I wonder if you find a way to paint the acoustic foam. I was not able to. The ugly color they do it so annoying. If you find way to turn it to a nicer color it would be so much more attractive. Also, my observation is that if case your room would be large the foam would work better but in case of small room the definers are much more effective then absorbers, not to mention the thy might look better. Your panels are very properly positioned and the combination of absorbers with natural diffuseness of the record shale is very good, still, now much fun would be if the foam would be in natural wood color…    In your posts before you told that you listening spot in the middle of the room and you have space to move your couch behind.  If so I would very strongly recommend to move the horns good 4-5 feet from the back wall and see what happens. You much have much more depth of you imaging and much more complicated layering with this move, try it, you might like it. You would need to reset your toeing of your speaker with this move. As you move the speakers closer to the center of the room try to let then to be pointed at your shoulders, not at your face.    In my view the absolutely best that you have done with your playback and it is something the I never seen before is to make bookshelf perimeter around you listening couch, it is so practical, comfortable and so attractive looking.! I absolutely love it. It also made the whole room feel like a human presence instead of a typical audio torturing chamber.    Regarding the symmetry. There is a community of people I know who brings a lot of argument and practical experiments defending asymmetry in audio listening. They do have point but ONLY in case of phase-misaligned installations. They have phase-random systems and asymmetry helps them, even deeper, to lose phase coherency. My personal experience the in context of phase-align systems a symmetry is very good, in fact the bore anal you go into symmetry the betters result would be.    Anyhow, congratulation with e nice setup. It took for you 3 year, right? I do not want to sound like a jerk and deficit at your parade… but I am so accustom to do so… :-) What I am trying to say. Get a vintage Tannoy Red 10 driver with original crossover and connect it along with your playback, in opposite phase with your MF channels. You might find it worth experiment with.. :-) "I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche

05-16-2018 Post does not mapped to Knowledge Tree kodomo Posts 69 Joined on 06-20-2015 Post #: 66 Post ID: 24858 Reply to: 24857 The room is bigger The room is actually bigger now (about 75m2) but the whole orientation has changed. The speakers were at the opposite side of the room near the windows. Having windows for a front wall had a detrimental effect on sound in the old layout. The absorption, diffusion and the vertical moss wall combination has a much better response instead. I insert a panoramic photo of the room to give an idea how the new room layout is. However, as the panorama distorts, let me remark, there is more distance from my listening seat to speakers, then from my listening seat to the windows at the back. It looks like opposite in the panoramic photo. Yes, very very close, I cross second order 110hz! this is what I have as final, great guess... It works great with the room like this. I have a lot of space behind couch. I tried speakers further away from the front wall and listened. This is about 55cm's away from the false wooden acoustic wall. That wooden wall is also 30cm deep, so the drivers are about 85cm's away from the front wall and with absorption (which kind of creates a deeper effect).  It took close to 3 years, which is about right, I was not expecting sooner, even without changing components, small adjustments took me a year to have a steady good sound. I still have things to try, but at least now I have a satisfactory reference point I can go back to or refer to

05-16-2018 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,672 Joined on 10-12-2006 Post #: 67 Post ID: 24859 Reply to: 24858 Very Elegant, and so Reasonable Things look to be in good proportion. Perhaps you have already tried the speakers off the walls?  I ask because that's how I've always gotten the best sound field/imaging, and generally the best overall sound quality; I move things around until I get acceptable saturation and scale from large and small works.   I guess one negative from moving the speakers away from the walls would be that the listening seats and bookshelves would push in front of the barn door and into the other sitting area?   The glass looks too "right" as it is to add vertical blinds.  In the high end houses around here they use electrically controlled shades that drop from boxes in the ceilings! Anyway, congratulations! Best regards, Paul S

05-17-2018 Post does not mapped to Knowledge Tree anthony Posts 338 Joined on 08-18-2014 Post #: 68 Post ID: 24867 Reply to: 24858 I see the cat... As you already know Kodomo, I am a big fan of your room...it is beautiful.  Those enormous speakers are so well integrated into the aesthetic that they are not the focal point of the warm and comfortable space.  As Romy says, your room is not a "typical audio torturing chamber" (I laughed out loud when I read that)...really well done!

05-19-2018 Post does not mapped to Knowledge Tree kodomo Posts 69 Joined on 06-20-2015 Post #: 69 Post ID: 24875 Reply to: 24857 Distance to front wall Here, you can see the distance to front wall. The wall is about 10cms behind the moss garden.About 35cms to the wooden binary diffusors surface. Another 55cm to the drivers and total distance to front structural wall is about 90cm (2,95feet) Maybe more distance could be better for stage depth or other stuff, but for distance needed for the total integration of the channels and a acoustically good point in the room dictates that this is the furthest they can be. All in all, the sounds are deeply layered, stable and harmonically and timbre wise very balanced. For the centre height of the stage, it is coming from somewhere between the tweeter and jmlc1400 horn, which shows great integration. The vocals and centre located solo instruments are also holographically playing in front of others with distinction when recorded like that without annoying or being harsh. The general decaying sounds, and room reverbs feel like actually decaying in the whole room but with control and no hangover. The most beautiful part is, it feels as if there is no effort in playing, it always feel like there is a lot of headroom (the room helped with that a lot) I am very much enjoying the current setup and listen to long hours without any fatigue. My wife says I have started to listen a little louder but it really is enjoyable to listen a little louder if there are no negative issues to the sound and no fatigue. The purepower also keeps steady sound by providing the same kind of electricity every play (if you know what I mean) which is great and means no depressing days out of trying to figure out what happened to the sound and why! In my case the culprit has been found out to be the electricity quality varying incredibly and measurably day by day.

06-17-2019 Post does not mapped to Knowledge Tree kodomo Posts 69 Joined on 06-20-2015 Post #: 70 Post ID: 25474 Reply to: 21722 New bass section As I already have written before, I was looking at different bass solutions for frequencies below 110hz with my set-up. As of this weekend I have set-up a new solution and will be evaluating and fine tuning it for the coming days. The new bass section is an H frame open baffle system with three 12" woofers with direct servo technology. They are driven by their own direct servo amps. After installing them, I disconnected both my dual tad1601b bass reflex boxes, as well as my 20hz tapped horn. Direct servo and open baffle technology seems to work well together for what is below 110hz. They integrated quite well both to my room and my horns. They are dialed in phase with the rest of the setup. They have close to 4 feet from the structural wall behind them. As far as measurements go, they show a more linear and deeper response. What was unexpected for me is the impact of the bass. I am not talking about the crude disco soundsytem chest rippers. The bass is layered, clean but impactful. It is airy, the bass does not take over the music but still delivers the power. I can hear the hall ambience better and the tympani hits are more distinct followed by their tails. The same goes for the cello and double bass. The tonality of the tads were beautiful and I am tuned to them. I will take some time to comment on the tonality of this system. Here is a photo of the room with new bass section. AI have put my studer a807 where my tapped horn used to be.

06-17-2019 Post does not mapped to Knowledge Tree Romy the Cat Boston, MA Posts 10,184 Joined on 05-28-2004 Post #: 71 Post ID: 25477 Reply to: 25474 Trying second time.... :-) Hm, it looks like I misread you post initially, now I got it. What type of crossover you use at 110Hz? You know that you will eventually will end up 3 more bass sections per side, juts give yourself time… I personally never had success with bass servo systems. In my experiments servo made different (that I did not like) type bass and I do not know it is it an overall topological problem with servo or it was specific to the given implementations that I was trying to use or was trying to listen. Did you use any off-the shelf servo solution of bold your own? Also, you think that positive things that you report is a testimony of the advances of open baffle servo bass or it is a testimony of inferiority of the taped horn? "I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche

06-17-2019 Post does not mapped to Knowledge Tree kodomo Posts 69 Joined on 06-20-2015 Post #: 72 Post ID: 25478 Reply to: 25477 Differences I have 2nd order crossover both on the upper knee of the ob bass section and on the lower knee of the midbass section. My measurements show phase response and the summed spl is as good as it can get.  Have you tried the direct servo technology or do you have experience with the older servos. The older servos relied on accelerometers and were slow to respond, the new direct servo technology seems to overcome this problem. The direct servo technology is by rythmik audio. Their website has information on this technology. The open baffle version is an addition by GR-Research. They have tweaked rythmiks amps for ob application (added dipole-cancellation comnpensation shelving) and also built paper versions for the drivers. They differ on these from what rythmik offers for their sealed and/or ported speakers..  The positive attributes may be partly because the ported boxes and a tapped horn working together was more complicated and had some inherent problems. The new system has no issues on integration to midbass, something I have not been aware of until I heard the new system. Also yy ported boxes had increased group delay at their lower end and that was around where the tapped horn was crossing in which measures fine but does not sound like a whole from 20 to 110. Tapped horn below 50hz is not a bad solution by itself. If my midbass played down to 50-60hz, I would not look for another solution. I would have just built another identical tapped horn. What is positive about the new bass section itself is how light but still impactful the bass is. That is how it works in my room at least. The room is treated to have an even decay down to 40hz and I am sure it helps the bass section integrate to horns. They sound similarly open and fast like the horn section. Still, I need to spend more time to become aware of its overall quality.  ps. I was going to get 12 drivers to start with and build 6 woofers each. If I am really satisfied with this solution, I think I will do that later on, that is on my mind.

06-17-2019 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,672 Joined on 10-12-2006 Post #: 73 Post ID: 25479 Reply to: 25478 Contemporary Solution Very interesting, and thanks for dropping some names to follow up on.  I understand this gambit from a sound engineering standpoint, and I am about ready to start considering some engineering again, myself.  It seems like you are enjoying the results, which it still where it's at, regardless of the approach.  May I ask why you chose 12" rather than 15" (or 18") drivers below 110 Hz? Best regards, Paul S

06-17-2019 Post does not mapped to Knowledge Tree Romy the Cat Boston, MA Posts 10,184 Joined on 05-28-2004 Post #: 74 Post ID: 25483 Reply to: 25478 The "old" servo... Kodomo, nope, I did not try any new servos and I do not even think I heard any servos over good 10 years. My main problem with servos, was that it made the same bass. I mean different avenues, avenues instrument, different music and different playing styles looks like produced the same bass. It was not good or bad bass but it was very recognizable bass and that structural predictably was something the bothered me very much. What I eventual felt that the servo was no able to play “slow”. I know that slow is not something the typically attributed to good bass but I beg differ. To me servo tends to decay too fast and with too low second harmonics. I love that high transient attacks with slow and wet release. Some dry vintage drivers do it very well, I did not see any servo did it. I do not know how the new servo work and sound however…  Conceptually any feedback system are very good idea but in practice many of them do not deliver. If however to perfect any given feedback system to its own excellence then it might very good result. I never perfected any servo systems in audio and I did not listed any of servo systems that did. What I heard/had was juts stock plan-vanilla servo implementation that might not be good to begin with. "I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche