timbley

---------------- On 4/30/2005 3:44:36 PM timbley wrote: This resulted in me having to turn down the tweeter about 6db, so you're going to lose about that much efficiency. ---------------- Actually, you're going to loose at least 12db efficiency because you'll have to include some EQ in your passive crossover to bring the bass back up. You really lose a lot of bass.

That's logical. It makes sense that it shouldn't work. For one thing, the cabinet and port was made for two 10s working together in the bass range, not for a single with a 10" passive radiator. I think you should sell those 5.5s and get a real 3 way. I think I'm going to do the same when I can afford to. I'm really intrigued with Al K's mod he's proposing for the Klipschorn. As much as I love my RF-7s, I'm going to make an argument that two 10"s arranged like they are have some real disadvantages for producing the midrange. They're not equidistant from the listener, and they're trying to cover the same tones. The result is uneven response due to cancellation and build up effects. The midrange is rough as a result, and the glare gets attributed to the horn more than it should. I swear, since I tried this little test in response to this post, it's obvious to me that vocals have sweetened, and the glare on some instruments has vanished! No EQ setting can do that. So I think you're on the right track as far as getting a 3 way. But yeah, what Dean said: get a speaker that's made for it.

Ah, that's different. I hadn't tried letting just one 10" driver produce the lower bass while the other produces midrange. That's a real 3 way. I had been trying a 2.5 way. For what it's worth, I just tried it. I set the crossover between the two 10s at about 722Hz. This resulted in me having to turn down the tweeter about 6db, so you're going to lose about that much efficiency. The upper 10 ends up working as a passive radiator as well as a midrange. It actually sounds pretty nice at first listen! And I haven't even tried to EQ it, other than turn down the tweeter. Hmm, I'd be interested in hearing what others think about this idea.

I honestly can't tell the difference which way the tweeter polarity is set. I can change it back and forth easily, and have listened hard for something to clue me in on which way is best, but heard nothing.

Re-designing a passive crossover, now that sounds complicated to me. Have you done something like that before? As for turning it into a 3 way by sloping one of the 10's to the middle octave, I've tried that on my RF-7s using a digital active crossover. I didn't like it much, but that may be just because I didn't do it well enough. How would you do something like that? Would you use the same crossover slope set to a lower frequency on one of the drivers? Or use a shallower slope set lower? Or shelf down one of the drivers and shelf up the other toward the crossover frequency?

---------------- On 4/27/2005 11:08:52 PM kenratboy wrote: ---------------- On 4/27/2005 11:06:33 PM timbley wrote: I hope it works. ---------------- Oh, it will. Just a matter of time, money and effort. IIRC, Texas Instruments first DLP display was 100X100 HUGE pixels and there was not even a color wheel. Now we are at 1920 X 1080 in a few months. Just wait ---------------- It will be interesting to see where this tech. takes us. I remember when I was in high school hi-temperature superconductivity was creating a lot of excitement. Room temperature was the big hope that never materialized. Maybe this will finally bring us there.

I hope it works.

I've gone nuts over LPs on several occasions, only to change something in my system and then end up preferring CDs again. I won't say with conviction that LPs sound intrinsically better than CDs, but I will say that vinyl can sound really, really good.

On the "O Brother Where Art Thou" album: The Soggy Bottom Boys

This is fantastic. I'll be watching with great interest.

On a similar note, I read that the soon to be released Panasonic SA-XR55 receiver will have a switch on it that allows the user to bridge the surround amplifier channels for more headroom during 2 channel listening. Pretty cool.

---------------- On 4/27/2005 8:30:21 PM Dylanl wrote: So make a comparison from before with passive to after for me. ---------------- In a nutshell, it's clearer and more detailed, from top to bottom. I was expecting more massive impact in terms of large scale dynamics, but I'm not really being super wowed by anything like that, although I do notice that some compression effects I used to hear during passages with heavy bass are gone now. One song like that is Gorillaz's "Clint Eastwood." It has cymbols bashing with heavy bass at the same time, and the cymbols used to get sort of flattened, which I thought was just how the recording was. They just couldn't shine very will with that bass. And I really couldn't hear the bass clearly either. Now I hear both very well. However, I could see how a good, single, high current amp may be able to flesh this effect out just as well with the passive circuit installed. But back to the clarity and detail, it's pretty spectacular. I find it hard to believe that any amplifier could be as clear with this speaker going through it's passive crossover, but I say that with some reservation because I haven't had experience with much high end gear. I notice that sounds seem to hang in the air better between the speakers, and the textures of those sounds are excellently resolved. Maybe this is microdynamics? It sounds like the edges are not rounded off, making a lot of things sound scintillatingly realistic to me. When I first hooked up this system, I noticed the bass improvemnt, an it struck me as majestic. It brought flashbacks of when I used to hang out at "Nuts about Hifi" in Silverdale, WA and listen to the big Wilson Grand Slams in the high end room. For whatever reason, this effect has worn off now and just sounds normal and good to me, and not as good as I remember hearing from my friend's Klipschorns. (I need to go listen to those again.) I think tuned port bass has it's limitations. The bass is very good though, and I think it might border on spectacular in a better listening room. It seems to go deeper than it used to, and I actually see some movement occasionally now on the RTA all the way down to 20hz, although it's dropped off a long way by then. I don't know how to describe it as far as warmth or richness, because I can control that to some degree with the EQ, and I'm still trying to decide what kind of balance I like best. I'd say it has no more or less than it did with the passives. I have heard a certain dreamy, romantic quality to other systems that I can't seem to copy with any EQ setting. I've also heard other systems that seemed more liquid smooth in the midrange and highs. I can't copy that either. Everything has some texture. But I couldn't get that effect with the passives either, and I think it actually is a little smoother and sweeter than before. But you know, I got to hear some Russian singers last week, live without amplification down at the University of Oregon. They were superb, and just three of them sounded like 10 somehow. What really wowed was their dynamic range. They started out soft, and I mistakenly thought that's just how things were going to be without amplification. But later they nearly shook the roof down! The whole auditorium reverberated, and my sense of direction of where the sound was coming from was largely lost, like bad stereo imaging. A lot of things that I thought were shortcomings of my system happened in real life. I heard their voices overlap and ocassionally cancel eachother out, leaving nothing for breif moments but the crackling breathy edge of one of their voices, or create oscillation effects like two drivers cancelling eachother out at a certain frequency and location. I heard the sound loud in one of my ears and muffled in the other if I didn't look right at them. The real sound didn't have that dreamy, romantic quality, nor was it liquid smooth like it was riding on a minsicus of medium weight oil. Their voices had a degree of hard edge. The Behringer/JVC combo seems to mimic the real sound pretty well to my ears, but not perfectly. It might suffer from a certain degree of "digititus," and may be unacceptable to someone adjusted to a more silken sound. I wouldn't mind having that silkly smooth sound sometimes myself. Now if they could just put in a setting for that... Mixing the Behringer crossover with some tube amps might make some beautiful magic. I'd say this system is mighty in "PRAT." I just can't sit still when I listen to anything with any kind of rythym in it. The whole body's got to move. I think it has more of that now than it did with the passives. One last thing, it resolves at low volume better. It sounds really nice down low, but will also go louder if you want it to without sounding strained.

I'm using a Behringer DEQ2496. 31 band graphic per channel as well as 10 band fully adjustable parametric per channel. The parametric has high pass, low pass, and shelf filters. Unfortunately, all the analog connections are pro audio XLR or 1/4" type. It does have optical spdif inputs and outputs though, so you can use it between a digital source and D/A converter easily. You can get one for under $300.00.

---------------- On 4/25/2005 4:28:21 PM jeffgeorge wrote: I'll be Madonna sounds pretty good on those cones! ---------------- Now that makes sense!

Some classical peice I've never heard on FM radio. I'd like to see a permanent field that allows us to share what we're listening to on every post. I saw that on another forum.

Yes, there's a filter in the tweeter circuit to bring it down to match the woofers, and flatten it's response. I was suprised at how far from flat the tweeter's response is, especially as it drops off very sharply long before 20k. It almost looks like a supertweeter on top could be useful. I see other tweeter response graphs that looks a lot flatter. I know very little about horn design, and practical limits of frequency response. For whatever reason, Klipsch decided that it was better to apply a filter in the crossover than to try to design a horn/driver that could give nearly flat response from 2.2 to 20k. Maybe that's just not possible.

---------------- On 4/24/2005 5:37:42 PM dragonfyr wrote: And, I am curious if you are taking advantage of the opportunity to align the acoustic centers of the drivers in the time domain with an appropriate delay offset... ---------------- I forgot to answer this on the last post. I've played around with applying delay to the drivers. I applied a little to the 10" midwoofers on the assumption that the horn driver is a little further back because of the horn length. I didn't notice any improvement. I don't have a way of testing the delay, so I was shooting in the dark just to see if I noticed anything.

---------------- On 4/24/2005 5:37:42 PM dragonfyr wrote: I would be curious to hear this, but I too fear that you are simply overprocessing the signal! And with each successive gain stage you are increasing the noise floor as well. And, I am curious if you are taking advantage of the opportunity to align the acoustic centers of the drivers in the time domain with an appropriate delay offset... And using the second zone stage to feed bi amp? Did I read this right? Wow, with so much variance and additional processing of the signal in so many ways.....I would LOVE (maybe the proper phrase should be "would be terrified"!) to see the transfer function of this total process! I fear that this is akin to going to a health food store to buy whole foods and walking out with just another insanely overprocessed protein powder...albeit with a bit price and a fancy label... ---------------- Curiosity is what got me into this in the first place. I would like to have someone else with audiophile ears to listen to my system and see what they think. Maybe they'd hear some obvious shortcoming I'm not. This system certainly does some high powered processing to the digital signal. I guess you could consider a digital EQ, or a digital crossover a gain stage. Neither introduce much of a noise floor. As for the digital EQ, I can't hear anything from that. The D/A converter on the crossover must add something, but most everybody has to have a D/A converter at some point, at least for their digital sources. I've only got one in the signal chain. The amplifier itself has the most audible noise floor, as can be verified by unhooking all the inputs and just turning up the volume and listening. There's really an extremely low noise floor in this system, so I rule that out as being any kind of a problem. I first started experimenting with digital processing using the DEQ equalizer. At that time, I was using it's digital input and output to a Panasonic SA-XR50, so there wasn't really any D/A converter at all. The noise floor was as close to absolute zero as I can imagine. It was easy for me to test the effect of the DEQ by bypassing it. After listening with and without the DEQ, it was obvious to me that it improved the sound in many more ways than it degraded it. It didn't seem to be degrading it at all, actually. I don't feel the DCX crossover is adding any audible degradation either, at least not from it's digital processing, although the D/A converter stage may not be as good as some. A simple resistor in parallel with the tweeter had a more damaging effect to my ears than applying some digital EQ and attenuation to the tweeter circuit.

It's been about a month now that I've been using my Behringer DCX active crossover. I've switched to using JVC-F10 receivers, two of them, to tri-amp the RF-7s. I heard immediate improvements in clarity and bass response by giving each 10" midwoofer on the RF-7 it's own amp channel. I've tried crossover frequencies ranging from 1.6kHz to 2.2kHz. At first I liked the lower crossover frequencies because the horn tweeter had a little extra snap to it. But with the 10" drivers each on their own amp now, I don't hear them giving up anything to the horn in the way of speed and clarity, so I've settled on 2.2kHz. Also, the dispersion seems better on the dual 10" drivers. Letting the horn go too low deadens room ambience in a way I don't like as much. I also tried doing a 2.5 way configuration, where the top 10" driver carries the midrange signal near the tweeter crossover by itself, and is joined by the other 10" woofer, which is crossed over lower to cover the bass. This sounded very similar to me to lowering the crossover frequency of the tweeter. It effectly reduces the cone area of the midrange sound. It sounds slighlty more accurate perhaps, but once again I didn't like it as much as when letting the two 10" drivers together carry as much of the midrange as possible. It's juicier, and it livens my listening room up more. I experimented with using a 10 ohm resistor in series with each tweeter, thinking it'd be better than applying digital attenuation. I get the impression that the resistor adds a slight glaze to the tweeter, so I removed it. I'm not hearing any problems with the digital attenuation, despite comments by some other DCX users. 48 db/octave slopes are my favorite. Shallower slopes work, but give up something in the way of clarity and imaging. Is this all worth doing? I can't say. I think I could spend the rest of my life playing with the EQ, never being sure of what I like best. The funny thing I've noticed about all audio upgrades I've ever done is that I appreciate them less and less as time goes by. I had a great time as a youngster listening to an AM/FM shortwave radio that had one "huge" 5 1/2" driver and a little tweeter. I was transfixed by music I heard out of that thing. So I upgrade, but eventually I don't end up enjoying music any more tham I used to, because I was already enjoying it completely.

---------------- On 4/24/2005 2:07:44 PM nicholtl wrote: Gosh, how I only wish I could monoblock my mains... ---------------- Why monoblock your mains?

---------------- On 4/22/2005 3:30:13 PM Thumpelstiltskin wrote: Who cares about the speakers, we've all got speakers. I want an air scooter!!! It flies 55 mph and can land on water!!! No license required!! Too cool!!! Rick. ---------------- It looks like a small helicopter with counter rotating blades. Small helicopters have been around for a while now. Counter rotating blades too. I don't see what's been invented here.

Bi-amping with the RF-7s passive crossovers is not worth the effort. The difference is small, and arguably not an improvement but degradation. I played with bi-amping this way for over a year. You're not helping the amplifier much to run the dual 10" woofers by removing the tweeter circuit load.

Nice pointy phase plugs seem to be the going thing these days. I wonder how these beauties will sound compared to the RF-7. Or, maybe I don't want to know. Never mind.

I noticed the inside veneer. Very nice. I was wondering why they did that, minimizing warpage from moisture abosrption makes good sense. I wonder if it adds anything significant to the cabinet rigidity and acoustic properties? A sandwich of two harder surfaces with a softer surface in the middle is supposed to be ideal, I thought.

I'm very sorry to hear of your losses. I totally understand the title you gave this thread. Life IS weird! I have no idea what God is up to. The good and the bad is all mixed together in our lives. We may not know what life is ultimately about, but despite all the pain and heartbreak, we seem to have an innate sense that it's all worth it. Good luck in your new job!