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Everything posted by pauln

  1. Recording quality is profoundly critical with nicer speakers that reveal more from the music. There are still some things that are difficult to record: - massed violins playing high and loud - large choirs singing high and loud - piano chords that consist of many notes played hard Some of the old methods of recording that only used two, three, or four mics from a distance avoided these problems. Modern close mic'ing with dozens of mics tends to raise this problem if the recording engineer isn't top notch. The problem is over-modulation of multiple complex frequencies that causes a faint "chatter" or "crackling" sound (your "metallic"?). MIC: "It's not you, it's me." Because the source is over-modulation happening in the recording microphone itself, what happens is that of say two mics recording the instruments, the mic closest to the violins for example will over-modulate but the far mic won't, so during playback the crackle is heard coming directly from the left speaker, while the apparent location of the violins is more in set from the left. This is why it is so noticeable and annoying - the crackle artifact is displaced from the instruments' location. This happens in both directions across the sound stage; any instrument section may overmod only the left or right mic, so the two channels playback the crackling sounds as if panned hard left and hard right. Only if the recording engineer allows both mics to be overmodded by the same instrument or section will the crackle take more central positions in the spatial sound stage imaging geometry. It is much easier to tolerate the crackle when it is spatially superimposed on the source instrument's position by playing back in mono mode - this forces all crackles to dead center along with all other instruments, and since the crackle is fairly low level it blends and is masked by the natural sheen of loud high massed strings, vocal phase warble of choirs, and the hammer bounce buzz of pounded piano chords, along with all the rest of the clear instruments.
  2. I think the stock black looks classy. No idea how one might produce that finish for an unfinished pair.
  3. I looked over there including the FAQ; it looks like the assumption is that +12dB is assumed to be enough dynamic headroom to not clip, but +12dB over what level? Average level or metered "fast"/"peak" level? I know, its -12dB down from full scale, but that is not enough. If +12dB over average, that is actually the middle of the range of recorded dynamic range (metered fast/peak over average) which means for the half of recordings that exceed that there is no more margin, and does not begin to include the additional 13dB required for transients. If +12dB over metered fast peaks, the transients are still not being fully powered. I think the dB level for the test file needs to be more like about -30dB in order to account for recordings with up to +18dB dynamic headroom above average and +13dB more for transients. This would cover just about everything except test recordings and those from a handful of specialty studios. The assumption that the listening levels are not clipping perhaps is not being met. Off to play records with milliwatts in the teens... edit... The more I think about it, the more I think I may be incorrect. Maybe the -12dB level of the file is arbitrary, just a way to calculate what the listened level power would be at full scale in order to access rated power required.
  4. That 1.8V is what the file produces when the volume is set to one's maximum digital media listening level. The listened level is an rms voltage corresponding to standardized ballistics (called "Fast" or "Peak" on meters designed for monitoring radio modulation of adult male "announcer voice" for commercial broadcast a very long time ago. Its ballistics accumulate energy about the rate of spoken syllables, which is what vu meters, spl meters, and watt meters display). There are at least 13dB additional dynamics above that level (instantaneous transients) that don't show up in the meters. But the file is a sine wave. It is also rms but does not have any instantaneous transients - if the file is down 12dB in order to present the range to 0dB as the overhead for transients, it is not enough. Why is 1.8V multiplied by 4? Dividing by 1.4 is converting from peak to rms but the measurement is already rms when read. Can you show the actual calculation with an explanation of all the numbers and units? .
  5. OK, but your figures appear to be 9db higher than mine... where is the other 3dB?
  6. How are you calculating power? Why not W=(V^2) / 8 ? which would be 4mW and 2.45mW averages, 0.9W and 0.4W maxiums
  7. Not only does the gasket provide an air tight seal and correct spacing between the driver and the horn; its inside diameter defines the design aperture for the throat. If you are operating for a while without the gasket in place, your throat aperture is larger than design, which means the horn produces less output level, which means you might turn it up to compensate but find the horn's relative level keeps sounding attenuated. Until you have a proper gasket in place with the right inner diameter, you might refrain from loud playing, and resist any loud testing or other exciting sonic experiments / investigations into why it might sound funny without the gasket.
  8. Here is another way to separate the high drivers from the low drivers, if you have a tube amp with multiple taps on the output transformer... These methods present the high and low drivers with different voltages from the same amp through the different taps of the output transformer. Multiple configurations are presented to get different relative attenuation. "Bi-tranny tapping"
  9. Wow, old thread... I'm still using the Sovteks that came with my Wrights 20 years ago. Birthday next month; maybe I'll get another pair of Sovtek, or maybe something else?
  10. The old method was to use a ballpoint pen; take it apart and use the big empty section, put the pin through the hole where the ballpoint stuck out. The tricky part is to not allow lateral pressure to the base of the pin where it enters to glass. That means you don't just push the pen body and bend the pin... you have to hold the pen body hole firmly and press the hole tip in the opposite direction from the pen body movement. Like bending a wire to make a sharp angle with your fingers - if your left hand was holding the wire a foot from where you want to make the bend, you don't just grab the wire and pull with your right hand, you set your thumb at the bend location and push while pulling with your fingers... the hole in the pen body is like your thumb, it keeps the lateral pressure from translating to the base of the pin.
  11. Please don't take this the wrong way; the designer did his homework, but don't be fooled. PWK referenced Kellogg who researched the production of bass frequencies with direct radiator speakers. To put it bluntly, a single 12 inch woofer playing a 50Hz tone loud enough that it is audible is already well into audible distortion... Kellogg needed something like 24 of these speakers to get the distortion down below detection even at low sound level. Nothing has changed since then; except that modern studios and modern listeners have agreed to believe they are producing and hearing loud clean bass... few people have ever heard true clean bass and would probably not like it without adding some grind and slam to make it sound familiar. I have had my Heresys for over 40 years and they are as good a design and implementation as it gets for that size, cleaner and clearer than just about all others, and the low end will hang in there with elevated bass EQ... but that is really just pushing them toward the normal distortion levels of other speakers.
  12. Even the professionals evaluate the sound of speakers up for review by comparing their sound to the reviewer's "reference speakers"... instead of the sound of real live music.
  13. just checking something...
  14. A pair of these under the front of both speakers works nicely, they even come in brown. If you look around, there are bigger ones for industrial use that might suit larger speakers...
  15. Because of the symmetry of the symptoms, it looks to me like there must be a systematic connection mistake on both channels... My theory - two wrongs make a right... you corrected one wrong, so what was right (two wrongs) is now wrong (one wrong and one right). I'm thinking the previous owner reversed a connection (probably on both the crossovers) and also reversed the corresponding connections (on the intermediary panels) either by accident or as a latter correction... the result was that the pair of reversals were incidental. At some point in your disconnecting (not checking for anything wrong) and reconnecting (connecting as expected to be right) you ended up correcting one from each pair of these wrong connections, so now each pairs' remaining wrong connection is no longer being corrected and showing itself. The insidious part is that your dilgence with making proper connections is probably the cause of the problem. The stock crossovers have wires from itself to an intermediary panel connection that has the provision for straps to distinguish a single full channel connection vs a dual split HF and LF connection... and then from there to the amp(s). I know it seems remedial, but all of these connections should be verified as correct. In all this is 20 connections for each channel. - the speaker connections on the crossovers (6) - the connections on the crossovers from the intermediary panels (4) - the crossover side connections on the intermediary panels (4) - the straps configuration (4) - the amp(s) side connections to the intermediary panels (2)
  16. Nikko put circuit breakers in some of their amps... Nikko was originally a circuit breaker manufacturer. I had a little 30W integrated Nikko amp with three circuit breakers with reset buttons on the back. If I recall, the three were for the power supply, the left amp channel, and the right amp channel.
  17. That will be a very nice combination, especially for records. I also play records only and my second system is Heresy and Sansui AU-6500, which is about the same power (28 Watts) as the AU-666. (both amps use the same pairs of 2SD188 and 2SA627 output transistors, both warm amps) The Heresy do not need much power to reach loud levels. Here is a way to think about it... For records you want +20dB dynamic range above your average listening level to ensure that peaks stay clean. That means your loudest average listening level would be -20dB with respect to the amp's rated power output. Conveniently, 20dB is a linear factor of 100, so 35 watts minus 20dB is 35/100=0.350 Watts or 350mW. So your loudest average listening level to stay clean on dynamic peaks is the amp delivering 350mW. Heresys produce 96dB with 1 W. To compare 350mW to 1W, use 10*log(0.350/1)= -4.6dB That means your maximum average Heresy sound pressure level is 96dB - 4.6dB = 91.4dB Distance makes this lower, room gain from walls and floor make it higher, two speakers adds +3dB. So you could estimate about 90dB very conservatively. Now 90dB as an average listening level is VERY LOUD, and for both the Heresy and the Sansui, an easy job. This will allow +20dB for dynamic peaks up to +110dB and still be clean, so very nice concert level margin. On most volume controls, the middle setting at 12 o'clock corresponds to about -20dB, sometimes, -18dB. I just mention this so as no surprise that you may find that you never need the volume knob near half way.
  18. There is a link to the PDF of the owners manual on this page... in the "Details" section under "Documents" Niles Audio SAS-1 owners manual It's Just Gone It's Just Gone
  19. In other news... if you are using tube amps with multiple taps for different impedance loads, there are some very interesting things you can do with how you hook up your speakers - if you have separate LF and HF connections on the speakers you can use the different taps to manage relative attenuation. Just scroll down to the first and second illustrations to see where he's going, then go back and read from the beginning. By the way, I have never seen these possibilites detailed like this anywhere else. VinylSavior - speakers impedance and taps
  20. The Heresy I has a "nominal" impedance of 8 ohms, but it actually is higher (which is good!). The lowest impedance value is 10.2 ohms at about 135-140Hz, so it is very easy to drive. You should be looking for a short circuit... - check the connections to the outputs on the back of the amp to ensure no stray stands of speaker wire are contacting the chassis - check same at the connections to the speakers - Unscrew the speaker backs and check inside for loose wires, retighten the terminal strip screws, look around in there (the inside of the backs have a connection from the crossovers to the back terminals... be carefull when you pull of the backs and check the connections on both sides of the back piece where the connections go through from inside to outside...)
  21. You can measure average voltage* from the output of the amp and use W=V^2/R to figure average power. Average power in watts is average voltage squared, divided by the load impedance. So for example, 15 volts average... (* Since the voltage is AC, the long term average is zero if you use a simple volt meter. You need a modern meter that is designed to measure AC voltage, or an old VTVM (vacuum tube voltage meter) with an AC probe.) W = (15 x 15) / 8 W = 225 / 8 W = 28 watts (28.125) You can specify watts and figure the voltage W=V^2/R so W * R = V^2 V = SQRT( W * R) So you might ask how much voltage is one watt (into 8 ohms)? V = SQRT( 1 * 8) V = SQRT(8) V = 2.83 volts (2.828) Sensitivity of speakers is measured with 2.82 volts (so 8 ohm speakers will be getting 1 watt) +20dB is a convenient figure for dynamic headroom over average level because it is a linear factor of 100. That means figuring the clean average level of power from an amp is easy - divide the rated power by 100. A 30W amp will have clean +20 peaks when its average output power is limited to 0.3W (or 300mw milliwatts). The conversion of output power to speaker sound level depends on its sensitivity, distance, and room gain. The distance and room gain often balance each other out. An average output level of 300mw in typical large rooms with La Scalas is going to be very loud. My loudest average listening level is about 10mw... that is only 1/100 of a watt. That seem a little crazy, but La Scalas are about 20dB more sensitive than average speakers. That is a linear factor of 100, that is like using a regular speaker with a sensitivity of 85dB/2.83V with a 100W rated amp played at its maximum clean average output of 1W - the result is about 85dB sound level in the room, same as the La Scalas with 10mw. 85dB is about the standard level agreed around the world for monitoring during engineering of recordings in studios throughout the decades of record production. This is the level at which the engineer established the tonal balance and many other things. With La Scalas, you should focus on the quality of sound at very low powers. All amps will have more than enough power for La Scalas; the question is how good do the amps sound running at low power. The specifications for amps don't show below 100mw because it takes much more expensive instrumentation to measure down there... and there are some very expensive amps that show high distortion levels down there.
  22. I see, the worst case is at about 4.3KHz where the distortion attenuation is least, about -30dB... so just over 3%. What are you using for a source?
  23. Well, first of all, second harmonic distortion is not even audible to the best ears until you have a few percent of it, and even then it doesn't sound like distortion at all. Most people can't tell anything until it is well above 5% and approaching 10%. So, measuring less than 0.15% is very good. As far as hearing sibilance, you can check a few things. Open the backs (and be careful because the crossover has connecting wires that feed to the back panel). - first, confirm the polarity of the mid-horn and tweeter connections are reversed in polarity compared to the woofer... in the type "D" it was not like that (all the polarities were the same), but Klipsch noticed in testing a slight improvement with reversing the polarity of the mid and tweet connections with respect to the woofer. The Dope From Hope Vol 15 No 1 may 1, 1975 has the explanation and diagram. All Heresys with a serial number after 14N517 have this change and the new crossover is called the "E" type. Since yours are D converted to E, this is just to verify the polarity was right (check both speakers). - check and re-tighten all the screw connections on the terminal strip of the crossover - unscrew the mid drivers from the mid horns to check the little gaskets. They look like the little rings you put in the end of a water hose to prevent leaking. If they are not cracked they are likely OK and don't even need to be removed. The driver is heavy, so be very careful not to cross-thread when taking it off or putting it back on. When you put the driver back on it should be "gentle firm tight", not screwed down very hard. See if any of these things help. If not, it may be that the crossovers are just old and the caps have gone bad. Visit this site and then call Bob Crites ( 479-967-1542 ) to find out what do do.
  24. I have not found that one... could you provide a link?
  25. Regarding the picture in this thread of the speaker with the big woofer and feet, ("How can you be pissed at this?"), I would answer by asking, "After all the decades of PWK's research, why am I looking at clear violations of the eight cardinal rules?", just one being the feet elevating it to form a cavity. PWK himself wrote research results of the catastrophic effects of placing speakers up off the floor like that. My thoughts... I think of "Heritage" applying exclusively to the old big five. For a long time, these were the company's best "pegs" scaled and engineered answers to the question, "What fits best into this hole?" That was a reflection of the old style relationship between maker and user, and the load was on the maker to present and identify the best solution. This is similar to the company Fender that used to offer two versions of guitar. In the last 20 years Fender has offered hundreds of versions of guitar... the load to identify the best solution has been transferred to the user. So I think of Heritage as meaning the collection of solutions from which the manufacturer presented the appropriate instance to the particular problem - the user said "I have this hole" and the maker said "I have this peg for that hole". For Klipsch, all this began to get a little slippy when the Quartet, Chorus, Forte appeared because of their strong "family resemblance" to the Heritage five. It was the design principles (e.g., Eight Cardinal Rules) that defined the Heritage five. The extended Heritage shared both the "look" of the five and some of those principles, but subsequent speaker designs moved away from them... to the degree that the underlying specifications of the new versions of even the old five were subject to change. So now, in some sense I don't even consider the new remaining versions of the five Heritage the same as the old five Heritage. Just look at the Heresy... Heresy I - rated 96dB/W/m and nominally rated 8 ohms impedance, but the minimum impedance is 10.2 ohms at 150Hz.Heresy III - rated 99dB/W/m but although nominally rated 8 ohms impedance the minimum impedance is 4.2 ohms at 150Hz. The international standard is that the nominal impedance specification is to be no greater than the minimum impedance times a factor of 1.25. For Heresy I, they could have spec'ed as 12 ohm nominal speakers (12.75 ohm) instead of 8 ohm nominal.Heresy III, they should have spec'ed as 5 ohm nominal speakers (5.25 ohm) instead of 8 ohm nominal. The sensitivity spec is with respect to voltage, not watts. The spec is 2.83V, which into 8 ohms is 1 watt, but 2.83V into 4 ohms is 2 W.To be more precise, 2.83V into 4.2 ohm is 1.9 watts. The difference between 2 watts and 1 watt is 3dB. And 99dB - 3dB = 96dB.Assuming the Heresy III more efficient is incorrect. The Heresy III needs close to twice the watts of the Heresy I to hit the same sound level. This kind of analysis is what the consumer is driven to do when a company expands their product line to the point of relinquishing their role as the provider of a best one-peg solution for each sized hole. This forest of choices forces the buyers to do their own math. Creating a "market of solutions" within the company forces consumer due diligence, and that level of effort is so similar to extending their purchasing scope to other companies' product offerings, that they do so, promoting lost sales. Kinda nerdy and rambling, but aren't we all?
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