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Delicious2

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Posts posted by Delicious2

  1. On 12/10/2018 at 1:00 PM, Chris A said:

    Okay, so based on my latest measurements today:

     

    1) The delay value for the AMT-1 channels is about zero (0), so a passive crossover can be used, but I'd recommend a first order.  I'm using 6 dB/octave highpass and lowpass crossover filters centered at 800 Hz break-point frequencies.  This is good for the passive crossover guys--a simple capacitor and inductor is all you need--no more crossover circuitry is needed, according to what I just measured.

     

    1464933137_CornwallbassbinAMT-16dBperoctSPLandphaseon-axis.thumb.jpg.adceea9be0a38e3509f984a91aece98c.jpg

     

    This of course includes quite a few PEQs to smooth the response to ±2.5 dB (using psychoacoustic smoothing, as shown above).

     

    2) I was fairly surprised by the difference between the left channel and right channel measurements, so I'd say that you would probably need to EQ in your own room via your own measurements.  I can certainly post mine here, but I have to say that the variability will probably nullify much of the gain that you might hope for. The good thing is that the frequency response without EQ correction is probably in the ±5-6 dB range, with about ±3 dB of ultra-smoothed central tendency wander of the response.  This is okay, but I would prefer a flatter response.  YMMV.

     

    3) If you're measuring the AMT-1s within about 2 feet of the reflective wall behind it, be prepared to see some interesting measurements.  I found that I couldn't use the same EQ on the left channel as the right--and that's really a first for me due to the fact that my listening room is pretty symmetric, except for the bay window on the left.  Apparently, this is enough to significantly affect the output of the AMT-1 as measured by the microphone at 1 m...significantly...

     

    4) I'm at a loss to explain the shift in measurements from last week to today.  Part of this is that I took a bit more time today to lay down absorption blankets, etc. so I could get much better phase measurements, but the delay values that I measured last week are not the same today.  I'd put a few hours of listening on the AMT-1s before trying to dial them in.

     

    Good luck. 

     

    Chris

     

    Getting ready to measure these tomorrow.  I'll be using the Xilica 4080 which has just enough inputs and outputs left to biamp these surround channels.  If it's not optimal to max out the Xilica, I  could employ a mini-dsp 2x4 HD.  Sounds like I should measure left and right separately at 1m with starting xover at 800Hz low pass 1st order for the Cornwall woofer and high pass 1st order 800Hz for the AMT.  Is this a good starting place to run an REW measurement sweep?

  2. 6 hours ago, garyrc said:

    We watch about 2 Blu-ray movies per week (occasionally 3 or 4) and I listen to either 2 channel or 5.0 or 5.1 channel music every day (ah, retirement!), all through the same system, L & R Klipschorns (stock, AK4 upgrade).  The center is a modified Belle Klipsch (top hat rebuilt, with a K401 replacing the Belle mid-horn, with the new top hat deep enough to accommodate it, while the whole enclosure, bin and top, is the height of the Khorns (tweeters equal height).  The whole thing is buried in the wall, in a bump out protruding through the wall, into the other side.  The Belle is thus flush mounted, and an equal distance from the Main Listening Position as the two Khorns (within 0.1 feet, according to Audyssey's distance (time) measurement.  There is no grille cloth on the front of the Belle, but that whole wall is covered with an "acoustically transparent" (I know that's like "clean coal") wall fabric.  Audyssey makes the treble response as flat as that of the Khorns.  Nothing is between the Khorns, except a wall mounted African bowl above the Belle.  The Belle sits on a strong shelf inside the bump out.  The sub (Klipsch RSW 15) is tucked under that shelf, and is also behind the fabric Surrounds are Heresy IIs.  They are slightly behind the listeners (more about that later). 

     

    Center channel and sub hidden behind wall fabric.  Other two thirds of wall solid, but fabric covered.  AT projection screen (Seymour), when down, makes apparently no audible difference in sound (it is one Roy tested for another forum member, and found, IIRC, 1.5 dB loss at the high end.  We flipped a coin and decided to run Audyssey with the screen down.  The room is usually under more subdued lighting than with this flash.

    DSCN1827.thumb.JPG.99a99d39b78af54b8d2984c6afb1ff5d.JPG

     

    Side wall

    DSCN1835.thumb.JPG.a29fbfa4c89356799c6c181ff2cbab09.JPG

     

    I haven't had the energy to start de-mastering yet.  Most of my classical SACD multichannel sound fine, as do the jazz disks.  I have a few other multi, including Dark Side of the Moon, which, as Chris A. said, is outstanding.  A friend convinced me to try Dolby PL II on two channel sources.  I resisted, but it turned out to be an improvement on some 2 channel disks, but a good number of our CDs need de-mastering -- or something.

     

    With the surrounds behind us, and as far as possible to the side, with some recordings (several movies, Dark Side of the Moon, the BSO/Levine recording of the Brahms Requiem, some Concord jazz SACDs, etc., the side walls come alive, with 6 or more loci.  Others suck.  

     

    Nice room/setup garyrc!  Cool stealth center! Have any shots of the Heresys or the LP?  Does the Khorns output cross in front of LP?  even with?  behind?  I like your description of surround envelopment: 

    "the side walls come alive, with 6 or more loci"

    I don't feel I've achieved that with my setup yet although my best surround recording (Gordon Goodwin's Big Phat Band -XXL DVD-Audio - the opening track "High Maintenance") is pretty amazing.

    • Like 1
  3. 1 hour ago, Chris A said:

    That's probably a good bet.

     

    I like the whole thing: the sparkles, and the impulse response (time aligned with the AMT-1 set back about 6 inches (15 cm), and the coverage improvement in-room over the stock Cornwall.

     

    Chris

    What...wait...Chris, you're time aligning with a physical set back?  What about REW? the Xilica?

    😁

    Seriously,  can't wait to play with these this weekend!  Wish there was some way to be breaking them in while I am at work but I'm sure I don't want to be running a full range signal though them much.

    How about some plush rug on  top of the cornwall bottoms (now tops) to hide wear and damp reflections?

  4. 2 hours ago, Chris A said:

    ...I'd find a top-of-the-line refurbished A/V preamp/processor having something like Audyssey, a Xilica XP-8080 (from MetropolisLakeOutfitters), and about 7-8 stereo amplifiers (or good class D multichannel amplifiers in one or more boxes having balanced XLR connections--like ICEpower modules), thus converting your rig convert into a multichannel hi-fi setup. 

     

    That would have some real fidelity and accompanying headroom...if everything was dialed-in using some REW measurements and the Xilica to do the dialing-in.

     

    YMMV.

     

    Chris

    not to sidetrack this too much but for the amps - wouldn't gain adjustable be important for dialing in gain stages/minimizing noise?  How about something like this?  https://classdaudio.com/sds-250c-4-channel-class-d-audio-power-amplifier.html

  5. 1392742715_LivingRoomLayoutPaint.jpg.c782fdfd8630ee9a1d9dd5fbe2f7bead.jpgHow

     

    How about using my room/system as an example 😀.  I know it's not ideal with the money seat up against the "back" wall but I've had some good sounds starting with some Michael Green "60s" up around ear level on cinder blocks for surrounds and a big ole THTLP sub standing up in the right rear corner.  Mains are by far the best I've ever had with the K402/TAD 4002/ Khorn bass combo.

     

     

     

  6. 3 hours ago, Tarheel TJ said:

    ...Any recommendations on some multichannel material to try out?  I am mostly a rock and roll guy, but I like just about everything.

    The prolific Steven Wilson primary creative force behind Porcupine Tree has mixed his own considerable body of prog rock work and classic albums of Yes, Jethro Tull, King Crimson, XTC and others into excellent multichannel DVD-A and Blu-rays.

     

    By way of correction Hell Freezes Over was made and released in 1994.

    (My bad...the song Seven Bridges Road is in fact from the earlier live album from 1980)

     

    We’re starting to see some surround titles with Atmos such as the excellent Hans Zimmer Live in Prague and the anniversary reissue of INXS - Kick 

     

    My resource for multichannel info is quadraphonicquad.com

  7. Excellent framing of the topic Chris.  Since your “interest” link is to my recent thread it follows that I’m very interested in this subject in fact I’ve been following the trail you and others have blazed with superb multichannel my goal.

    One area where I can’t simply duplicate what you’ve done is my room so I’m glad you listed suitability of the room.  Our rooms are quite different in part because my L+R are much further apart and my LP up against the “back” wall.  Is it even possible to get excellent multichannel in my living room?  What are the inherent difficulties you’ve overcome or minimized in your room setup?

    • Like 1
  8. On 12/10/2018 at 8:33 AM, Chris A said:

    Actually, you should get an increased backwave reflection from the corners since they form a (squashed) tetrahedral horn vs. the gain from a flat back wall. And since Khorns are typically placed in corners symmetrically, i.e., 45 degrees from each wall or false corner, you will get a fairly nice backwave reflection from the AMT and perhaps a little more diffusion from the tetrahedral surfaces that should increase the sense of depth of the resulting images. 

     

    In any case, it's certainly worth a try on the Khorns.  Except for the three or so PEQs that I showed above (and reproduced again below) if you cross below 2 kHz, all you need to do is match SPL of the AMT with the midrange using a hand-held SPL meter. Note that I haven't had a lot of run-in time on the AMTs, so I reserve the right to update the PEQs below based on simply using them for a little while.

     

     

     

    Chris

    I ordered 4 of the big AMTs the other day :0) hopefully they wont' be back-ordered.  Picking up a 33 year old pair of Cornwall "1.5s" tonight on a local CL sale.  It will be fun to experiment with 

    • Cornwall stock surrounds
    • Cornwall AMT surrounds
    • Cornwall Stock center channel between K402 blends in living room and basement
    • Cornwall AMT center channel

    Would the AMTs be worthwhile trying on top of the K402s perhaps augmenting the TADs or BMS full range or rolling them off and running the AMTs in the highest octaves?

  9. 23 hours ago, Chris A said:

    Actually, you can talk to @Delicious2 (Mark Haskins) about using Khorn bass bins and K-402 assemblies on top, thus saving significant dollars over full-up Jubilees if you can locate a pair of relatively inexpensive used Khorns in good condition (usually available in the $1500 range if you bargain).  I think that Mark's very pleased with the results.  I know that the REW measurements of the differences between Jubilees and Khorn/K-402s was smaller than I expected--surprisingly good, in fact. 

     

    I think this combination (Khorn bass bins with K-402 tops) is probably one of the best well-kept secret around on the forum...but Mark will, I'm sure, let you know about the listening differences.

     

    Chris

    I must say up front that I've never heard Jubilees.  I already had 1990 Khorns which I had modded and enjoyed for years when I went K402 on top recently.  I Initially dialed them in with Chris' help going active with a Xilica 4080 and amps I already had driving the Khorn bass bins and BMS 4592 NDs (coaxial) on top as a 3 way.  I have never before experienced that great a leap in performance of a system in the same room!  The wide open, dynamic, "live" sound of the K402 has to be heard and my Khorn bass bins have never sounded near this good.  Together they have a cohesiveness that is addictive.

     

    You could go much of the way on this road with about $2200 for the K402/K691/stand set and about $900 for the Xilica.  Use 4 lower powered/ lower gain (or adjustable) amp channels that you may already have for a 2 way active setup and prepare to be launched into a new level.

    Don't shy away from the calibrated mic and REW software needed to dial these blends in for your room.  I'll walk you through that part if you like and Chris can help with the Parametric EQ to apply in the Xilica software.

    • Like 1
  10. On 12/6/2018 at 1:19 PM, Chris A said:

     

    I'm listening to these surround Cornwall/AMTs right now playing a 5.1 Yellowjackets New Morning Blu-Ray.  It's pretty spectacular.  It's also possible to move the AMT-1 around to put the HF energy where you want it in-room. As surround loudspeakers in a 5.1--this is something that I've wanted for a long time.

     

    Chris

    So I'll be looking for compatible surround speakers for both my living room setup with K402/TAD/Khorn L+R and the HT setup with K402/BMS4592ND/Peavey FH-1 L+R.  Should I be looking into used Cornwalls?  At least buying 2 pair of these tweeters while on sale?  I get that they need some room to breathe.  The only thing better would be...?...K402 MEH?

     

  11. 11 hours ago, Tarheel TJ said:

    I know this setup is still very much a work in progress, but what are your overall impressions of the TAD beryllium vs. the BMS co-axial?  Which produces better highs?

    HeHe,  that's the $3500 dollar question isn't it?  I certainly had a chance to compare them well tuned through the Xilica by Chris not at the same time but in sequence - first the BMS active 3 way on the Khorn bins (no BMS passive mid/tweet network connected) for a couple weeks then the TAD beryllium 2-way through the same source, pre-pro, Xilica and amps.

    The cynic or purist might say that such a comparison is obscured or even invalidated by the extra A/D-D/A conversion of the Xilica or its inherent sound imprint or my poor choice of cables or all 3.

     I'm not saying that :0)

    • I will say that my goal is highs that are well integrated with the music (don't call attention to themselves - as in -"listen to those highs!")
    • Highs that are true to the recording (e.g. piercing if the recording is, sibilant if the recording is, well balanced and revealing of treble instrument timbre - if the recording is)
    • I'm aware that I'm probably in a transition period of training my mind/ear to be satisfied with less hyped high frequencies (happening whether I like it or not as I age)
    • In the "wouldn't it be nice" department I'd like a soundscape that frequently has "air" - that elusive sense that the performers are in my room or I've been transported to the venue.
    In the recent sequence of listening the TADs approached these goals best.  
     
    I'm looking forward to tuning the BMS in the HT room trying both passive xover and full 3 way active.

     

    • Like 3
  12. Here's some initial pics of the K402 BMS 4592ND Peavey FH-1s in the HT/mancave.  Still got the old Acarian Alon center in there for some reason.  Xilica 8080 over on the floor on the left temporarily and an Anthem MCA525 five channel amp.  Unlike when they were on the Khorn bass bins, I'm running the BMS 4592NDs with their passive mid to tweet xover, so, just 2 way out of the Xilica.

    K402 BMS 4592 Peavey FH-1 in HT both.jpg

    K402 BMS 4592 Peavey FH-1 in HT right.jpg

  13. This blend now with K402/TAD and Khorn bass has a lot going for it.  I often like the "widescreen" effect I get with them on the living room long wall but sometimes even with the K402's wide coverage I sense a "retreat" in the middle if not an outright hole.  There's no way to have a K402 MEH in the fireplace so what about a circuit that will allow me to vary stereo spread?  I know there have been preamps with this feature.  Can it be added and be fairly transparent?

     

  14. 26 minutes ago, ODS123 said:

     

    A bit tangential to your point....

     

    One thing that has always struck me as sort of silly is the notion that good speakers NEVER cause listener fatigue.  You'll read posts like "I can listen all night long to XXX speakers and never feel the urge to turn it down or turn it off."  Well, as someone who has heard a lot of life music, I can tell you that REAL music played in a proper venue can absolutely cause listening fatigue after a while.  Trumpets, flutes, violins, and violas, (just to name a few) even when played by exceptional musicians, can start to grate after awhile.  So I always wonder, if speakers NEVER causes listener fatigue, then what isn't the speaker recreating that was there during the performance?

    It has sometimes occurred to me that the best system would be like a chameleon - true to the recording and the music whether it was soothing, grating, agitating, inspiring or (insert adjective here).  Not sure I have ever encountered such a system or whether I would want to listen to it for long never mind own it given the apparent dismal state of mastering Chris describes.  It seems I could do with some ear "retraining" and so no longer crave the audio "junk food" of music mastered for earbuds and car stereos.

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