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How to dissect polar patterns and frequency responses for horns.


Droogne

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The K-510 horn with a Faital Pro HF200 series driver, suitably dialed in, will have a smoother sound and will have better polar control, both vertically and horizontally, to a lower frequency, without any issues with higher order modes (HOMs). 

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2 minutes ago, Chris A said:

The K-510 horn with a Faital Pro HF200 series driver, suitably dialed in, will have a smoother sound and will have better polar control, both vertically and horizontally, to a lower frequency, without any issues with higher order modes (HOMs). 

Planning on buying a good crossover for it, but for now the passive will have to do. Might try out the active I have now (which is only a DCX 2496 I know..) to compare them. Depending on that I might upgrade a bit sooner to the Xilica. 

 

But for now:

 

3-way fronts with 2-way centers: best speaker as center

or 2-way fronts with 3-way centers: best speakers both in the LCR

or 3-way fronts with heresy centers and 2-way centers: best coherence (LCR would be all K55 + K77 mid high)

 

 

 

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@Chris A

 

I've come up with another solution, which seems to be a lot easier, straight forward and would be a great way to step up. I was so caught up in my K55/K77 driver combo, that I kinda neglected the option to just sell them, and not build the LaScala bins. With the money I save and earn I could directly build my custom height channels with the HF200 driver (on the PH2380 horn), but use them as a center channel between the HF200/K510/LaScala fronts. Later when I have the MEHs I can move the Lascala K510 to the rears, and mount the custom heights. Later I could upgrade those PH2380 horns to K510 horns. 

 

I know a non fully horn loaded is a downgrade, but it's only temporary so that's not an issue. Building a horn loaded height channel seems impossible so it will have to be direct firing (except if you know of a horn loaded mid bass cabin that weighs less than 15kg and is within my size restrictions, see below). The plan I have now is:

 

a 40(depth)x70(width)x45(height) (around 80-100L) enclosure with double 10" woofers. A single 12 could also work but I'm height restricted (max 48cm height). Double 12" would be too heavy. It could still work (double 12s) if I find a woofer which can work in a really small enclosure (so less weight) and doesn't weigh too much (around 3kg). For now I was thinking about the Eminence beta 10B, although it seems the Eminence Alpha 12 could also work. Both weigh less than 3kg, have great sensitivity and can work in small enclosures. Eminence even recommends 20-25L for the 12"er. 

I would mount the horn directly on top of it, so not  in the enclosure. That way I can easily swap the horn out for a K510 horn when the day comes. 

 

I would use my DCX2496 as crossover. 

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  • 2 weeks later...

@Chris A  Have been wondering about polar control and  seating angle/distance. What is the effect of perfect polar control on this? When people talk about the Jubilee, they always mention the perfect sound across the whole room, not in one hotspot. What would the effect be on seating placement? Would this mean less tooing for perfect sound at the main SP? And better coverage across the whole room? 

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3 hours ago, Droogne said:

When people talk about the Jubilee, they always mention the perfect sound across the whole room, not in one hotspot. What would the effect be on seating placement? Would this mean less toeing-in for perfect sound at the main SP? And better coverage across the whole room?

 

The idea of a HT that differs significantly from stereo-only hi-fi setups is that more than one person can enjoy perfect sound at the same time--all across the width and length of the room, to within a metre or so from the loudspeakers.  This is where the K-402 comes into its own.  Toe-in of corner loudspeakers is still needed to center their coverage of the horns within the room boundary (i.e., you're not painting the walls with a lot of acoustic energy relative to the direct-arrival sound at the seats), but within that coverage, you will have 90 degrees of sweet spot--just like at a large cinema theater.  This will fill the entire room with spectrally balanced sound, which I believe is about 75% of the magic of the K-402 experience in a home-sized listening rooms.

 

If you design your listening room for a sweet-spot-only performance using some other type of horn without good constant coverage polars, then you're basically back to 2-channel-only operation.  When you step outside of the narrow area of the sweet spot, you are then listening to spectrally unbalanced sound--like you've got poor loudspeakers that require very selective toe-in to get the sweet spot right.

 

3 hours ago, Droogne said:

Have been wondering about polar control and  seating angle/distance. What is the effect of perfect polar control on this?

The "perfect polar control" that you are referring to will provide extremely insensitive aiming performance--much less sensitive than any "hi-fi loudspeakers" that you've heard.  The K-402s cover the entire room with direct arrival sound (when aimed properly).  What you will notice is that the early reflections that are within 0.5 metre of the horn mouths will have an effect on the sound stage imaging due to the strong early midrange arrivals of reflected energy off nearby wall surfaces.  These early midrange reflections I've found disrupt the soundstage and in particular the phantom center image of stereo. 

 

When you aim the K-402s to minimize early midrange reflections, but still pick up the midbass and low bass performance of the nearby walls, the soundstage and center imaging encompass the entire end of the room and balanced, clear sound that it not strident or otherwise spectrally distorted.  The K-402s, in my experience, draws you in to the listening field like nothing else in home hi-fi.  With good recordings (i.e., those acoustic that preserve the original musician's acoustic performance without significant editing or EQing), the K-402s, well aimed and with nearby absorption on the adjacent walls within 0.5 metre, will draw you into the performance itself, allowing to to hear details within the recording that you've not heard before. This is due in no small part to the controlled polar coverage vs. frequency with these horns.

 

Chris

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Now this might be a controversial opinion but I think the vast majority of popular music (ie multi tracked rock, pop, etc) needs some help from early reflections to sound "good". Othewise you get a flat, forward image.

 

Where I loved the full Jubilee system I heard was with non-popular music (jazz, classical) that is well recorded where it truly felt like a live like experience from soft/small dynamics (I guess what audiophiles call microdynamics) to full scale dynamics. With this music the recording microphones have already picked up any depth/image cues so this doesn't need to be artificially painted with the speaker/room interaction.

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2 hours ago, jazzmessengers said:

...I think the vast majority of popular music (ie multi tracked rock, pop, etc) needs some help from early reflections to sound "good". Othewise you get a flat, forward image.


Truly early reflections (delays of 0.5-5 ms) I've found destroy the center stereo phantom image.  Reflections of longer duration (5-25 ms) tend to muddle the clarity of the performance, but sometimes increase the sense of depth and/or width to a small degree (like the Bose Wave Radio effect).  But it's the delayed reflections of over 25-50 ms that actually give a sense of presence and envelopment.  Note that you really can't achieve delays of that magnitude in a small listening room from two loudspeakers using playback room reflections--the reflection delays are too short. 

 

You need surround channels of at least 50 ms delay (and 100-200 ms is more effective for many genres) to actually improve the listening experience in terms of envelopment.  Floyd Toole talks about this in his book Sound Reproduction: Loudspeakers and Rooms. You can achieve those longer delays, but you need something like a stereo-surround converter (like those found in AVPs and AVRs) to achieve delays of that magnitude.

 

2 hours ago, jazzmessengers said:

Where I loved the full Jubilee system I heard was with non-popular music (jazz, classical) that is well recorded where it truly felt like a live like experience from soft/small dynamics (I guess what audiophiles call microdynamics) to full scale dynamics.

What I've found in my demastering of CDs is that the problems apparently come from the following sources:

  • mastering compression,
  • recording the tracks in a "dry" venue--like a recording studio exclusively doing multi-track assembly of performances without sufficient volume of rooms to produce perception of envelopment, and
  • equalization (both at mixing and mastering time) to increase perceived loudness

I've experienced CDs where the dryness of the venue was a bit overwhelming...but I've experienced many times more where I got an old version of the CD with higher dynamic range, and compared it with multiple "remasters", and found that the problem is compression/Loudness War practices.  If you find that your recordings need help due to impression of flatness, I recommend doing some demastering.  You will be amazed at what you experience--both in terms of increased enjoyment and understanding of what is actually occurring within the recordings themselves that were disguised for sale. 

 

I find that demastering dramatically increases the fraction of recordings that are worthy of listening to.  If you are interested (and you have a setup that's been dialed in--including the room acoustics), then I've got examples that you can try out in A-B fashion.

 

Chris

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13 hours ago, Chris A said:

 

I find that demastering dramatically increases the fraction of recordings that are worthy of listening to.  If you are interested (and you have a setup that's been dialed in--including the room acoustics), then I've got examples that you can try out in A-B fashion.

 

Chris

 

For popular classic rock (ie Allman Brothers, Cream, Grateful Dead, etc) there are actually many audiophile versions of these albums on CD or SACD (with redbook layer) that are pretty damn close to flat transfers from the master tapes or only have 1-3 db of boost/shelf in some frequencies to massage errors in mixes according to the mastering engineers I've spoke to and they never use compression. There was also a series of CD/SACDs released by Universal Japan several years ago that were purely flat transfers of the master tapes with nothing else done to them, many popular classic rock albums were done in this series, there is a huge thread on the Steve Hoffman forum about them. In the liner notes they included the tape source (some albums have master tapes stored in the US some in the UK), mastering studio and mastering engineer name and a few of them verified that they didn't do anything to them per Universal Japan's wishes.

 

I will have a read through Toole again on reflections, guess I misremembered on when the reflections are happening.

 

With regard to surround, I would say at least 95% or more of the music I like is stereo mix only.

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2 hours ago, jazzmessengers said:

For popular classic rock (ie Allman Brothers, Cream, Grateful Dead, etc) there are actually many audiophile versions of these albums on CD or SACD (with redbook layer) that are...close to flat transfers from the master tapes or only have 1-3 db of boost/shelf in some frequencies to massage errors in mixes according to the mastering engineers I've spoke to and they never use compression...In the liner notes they [i.e., concerning Universal Japan's master tapes] included the tape source (some albums have master tapes stored in the US some in the UK), mastering studio and mastering engineer name and a few of them verified that they didn't do anything to them per Universal Japan's wishes.

 

You might want to look at the tracks themselves to see if what you've read is actually true.  From my demastering experiences from my own CD music library, I've learned that you will likely be surprised. 

 

2 hours ago, jazzmessengers said:

There was also a series of CD/SACDs released by Universal Japan several years ago that were purely flat transfers of the master tapes with nothing else done to them, many popular classic rock albums were done in this series, there is a huge thread on the Steve Hoffman forum about them.

A link to that thread would be nice for others to follow from this thread. I might pick the wrong thread.

 

2 hours ago, jazzmessengers said:

With regard to surround, I would say at least 95% or more of the music I like is stereo mix only.

 

Note that I was referring to the ubiquitous two-to-five channel sound processing in my reference above--that creates a delayed sound field from the stereo original to create delayed surround channels in a 5.1, 7.1, etc. 

 

I've found that loudspeakers that cannot control their polar coverage vs. frequency don't have many virtues--no matter how much some wish to think better of them.  There are other issues (notably loss of clarity--among others) that are introduced when the sound in the upper midbass, midrange or treble frequencies are splashed around at playback time in the room's boundaries due to the loudspeaker's loss of polar control. 

 

Listening to the Jubs over the past 10 years or so, I've found that that increasing the nearfield direct-to-reflected energy ratio significantly improves the experience of listening--for even poor recordings.  

 

Chris

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On 1/28/2018 at 9:53 AM, Chris A said:

 

You might want to look at the tracks themselves to see if what you've read is actually true.  From my demastering experiences from my own CD music library, I've learned that you will likely be surprised. 

 

A link to that thread would be nice for others to follow from this thread. I might pick the wrong thread.

 

 

Note that I was referring to the ubiquitous two-to-five channel sound processing in my reference above--that creates a delayed sound field from the stereo original to create delayed surround channels in a 5.1, 7.1, etc. 

 

I've found that loudspeakers that cannot control their polar coverage vs. frequency don't have many virtues--no matter how much some wish to think better of them.  There are other issues (notably loss of clarity--among others) that are introduced when the sound in the upper midbass, midrange or treble frequencies are splashed around at playback time in the room's boundaries due to the loudspeaker's loss of polar control. 

 

Listening to the Jubs over the past 10 years or so, I've found that that increasing the nearfield direct-to-reflected energy ratio significantly improves the experience of listening--for even poor recordings.  

 

Chris

 

Here is the thread, but I don't think it will be all that helpful unless you have loads of time :lol:http://forums.stevehoffman.tv/threads/platinum-shm-cds-launched.323981/

 

I say this because the forums there have very low SNR and the actual useful information is in the 5% range. Please feel free to message me if you'd like samples of any of these, I bought them for all the bands I was interested in and compared them to numerous versions (as well as emailed some of the mastering engineers who as usually forthright and happy to talk about their work).

 

Note that if the mixes are unbalanced sounding there is not a whole lot good mastering engineers can do to try and fix them, and the good ones I've spoke to pretty much leave them alone instead of trying to create huge boosts/suckouts in EQ.

 

I avoid remastered CDs as well, particularly those released by the major labels, these are often remastered in a way to sound good in car stereos or low quality headphones.

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Looks interesting. I'll take a more in-depth look at the thread.  You're right about "low SNR" ;).

 

One observation in passing: it was Steve Hoffman's "remastering" of the Steely Dan Aja album for MFSL that caught my attention during my early investigations looking at correcting poor sounding CDs so that they sounded much more like actual performance.  When I was looking around for what the cumulative spectral density curves should be, I reasoned that I should first look at CDs that sounded the best for each genre of music.  What I found with the MFSL Aja disc was that the cumulative spectral curves all looked the same...very much like this one:

 

Take the Highway (Live) Final Corrected Spectrum.GIF

 

It also turns out that after applying different target cumulative frequency response curves from different genres of music that I found, the cumulative spectral density curves that Steve Hoffman created (or more likely...simply left them alone) for the MFSL Aja album tracks seemed to sound best..and not only for jazz fusion genre but for all types of music genres for music tracks having relatively full instrumentation and rich overtones throughout the audible spectrum.  It's also very easy to explain why this cumulative spectral density curve works.  All you need is Audacity freeware to have a look and perhaps correct the tracks...if you're so inclined.

 

Chris

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Sorry if I mentioned it before but one striking effect of Chris' remastering is improved realism... very noticeable with drums.  Some of his examples seemed a bit bass heavy at times but that could also have to do with my set up somewhat.  I think you revisited some of your Audacity tweaks at some point.   I seem to be all thumbs in my attempts to do this myself but I might have given up too quickly.  Perhaps I need a good headphone amp so I can take advantage of my Beyerdynamic phones and not suffer the limitations of my room.   It certainly is cheaper to do this yourself à la Audacity but if I feel lazy enough I can just go with MFSL.  The few I've heard have been pretty good... at least better.

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I had a period of time in mid-late 2006 whereby I lost calibration on my setup due to the gain controls on the subwoofer amplifiers turned down too far (...puppies are at just the right height to chew on the little knobs...). I demastered a lot of tracks during that period.  This was a living, real "lessons learned" that I won't forget anytime soon. 

 

I recalibrated the setup and have been going back to those 2006 tracks a little at a time, updating the relative bass levels.  The advantage of having those tracks already partially demastered is that I don't have to do much to re-level the bass lines--it takes a few seconds per track.

 

As far as being "all thumbs"...I've been there, too.  It's been the last 18 months that has been most effective (I started in January 2015 from scratch).  I've learned the process includes a first pass through to take out the majority of the "custom mastering EQ", then at least a second pass through to re-voice/refine the tracks, especially for the most demanding recordings, e.g., solo piano, violin, perhaps surprisingly...full rock band, and some select tracks from the 70s-80s that have a lot of "nostalgia". 

 

I'm like a lot like other people in terms of being too impatient, but I've learned the hard way that it's the last bits that make the difference.  Coming up with a basic demastering process (from whole cloth) and looking...closely...at the plots to see what is occurring in each track has been reinforced during the development of my fine tuning process.  This is the "light touch" portion of the process that comes more and more easily with time.  It's a bit like any skill--the more you do it, the easier it is--like playing a musical instrument, etc.

 

I've finally created detailed outlines of a series of YouTube tutorials on "How to Demaster your Music", but I've been having some startup issues with my sound settings (microphone+music playing at the same time, etc. , getting a quiet environment to record without disruptions, etc.), as well as setting up the screen size to see the spectrogram and cumulative spectrum plots on a YouTube-sized screen that also been a bit of a challenge.  Sometimes it's really important to display the plots at full screen size to see what's going on, but you can't display the plots at full screen resolution on YouTube.  So compromises must be made for the videos. 

 

When I finally get through those roadblocks, I'll post the videos for review and comment for a couple of people before "going live". 

 

Chris

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  • 3 weeks later...

@Chris A Another question about custom height channels. I'm looking into a synergy horn that could work, but I cant seem to figure a way to get the crossover down to 500hz. Only option is using a SEOS30, but that one is too big. A SEOS22 could work, but has a crossover that is too high. Other option is to have the synergy use a higher crossover, but then I would kinda lose the advantage of the synergy in polar contral (especially in the smaller horns I would be using). What options do I have if I want to use the same driver (HF200 or 140). Would the horn you once recommended be a better fit? I doubt it, but who knows. (https://www.ebay.com/itm/11-x-17-ABS-2-Bolt-On-Long-Throw-Horn-90-x-40-For-Many-2-Exit-Driver-/331676072699)

 

 

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1 hour ago, Droogne said:

I'm looking into a synergy horn that could work, but I can't seem to figure a way to get the crossover down to 500hz. Only option is using a SEOS30, but that one is too big.

Well, I guess that an MEH crossing over at 500 Hz will be too big, unless you can figure out how to miniaturize sound waves...:D

 

Seriously...the SEOS 30 is actually about as small as you can go without losing polar control at the horn mouth at or before you get there (with a little margin to spare...which you'll need before you're done).  What I'd recommend looking at is using a big-mouth horn that's fairly short--like a straight-sided horn...also called "conical". Then worry about how to package that size horn mouth in your height channel placement areas.  Then I'd recommend looking hard at more unorthodox room placement positions.  You'll find that you can do it with some amount of compromise, but you'll be giving up some or all of the low frequency performance unless using a largish open baffle or box around the horn mouth.

 

Chris

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3 hours ago, Chris A said:

Well, I guess that an MEH crossing over at 500 Hz will be too big, unless you can figure out how to miniaturize sound waves...:D

 

Seriously...the SEOS 30 is actually about as small as you can go without losing polar control at the horn mouth at or before you get there (with a little margin to spare...which you'll need before you're done).  What I'd recommend looking at is using a big-mouth horn that's fairly short--like a straight-sided horn...also called "conical". Then worry about how to package that size horn mouth in your height channel placement areas.  Then I'd recommend looking hard at more unorthodox room placement positions.  You'll find that you can do it with some amount of compromise, but you'll be giving up some or all of the low frequency performance unless using a largish open baffle or box around the horn mouth.

 

Chris

Size is actually not a real concern, weight is. My size restrictions are pretty flexible. I don't have a girlfriend or wife so I can get away with almost everything. I live with my brother and I doubt he is gonna mind. I think I can manage up to 100x40x60cm in size for the height channels. I can mount up to 40kg, but I would like to keep that weight down to 30kg to be safe. Price is also not a real concern as that would only mean saving a bit longer. So if only the SEOS30 would work I could live with that. They are only height channels, so they will never ben run seperately for critical listening. 

I already asked you in another thread what the highest MEH crossover could be, precelisely because I would like to have the same for all speakers, and it looks like 500hz is pretty hard for a height MEH. This begs the question. What would be the best timbre matched setup in your opinion:

 

1:

 

all 11 using same crossovers points, but having to use a hoger crossover for the mains (let's says the MEH). For example all 11 channels @700hz so that the heights can use the same cross as the ground levels.

 

2:

 

Ground level at their native 475hz. Heights at an appropriate cross (7-800 for example), but using same high.freq driver etc.

 

I know I have to compromise, but I'm not sure yet where. 

 

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@Chris A, not sure if I ever proposed it , but what would you think about using something like Jack 10 from BillFitzMaurice (http://www.billfitzmaurice.com/Jack.html). It can cover the range it is required to, and it has great sensitivity. Weight and size wise it would also work. I know it would not perform nearly as well as a decent MEH, but it would be way better than a direct firing right? 

 

To recap, so this Jack10 with a K510/HF200 combo on top with a 475 or 500 hz crossover (active). 

 

 

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On 2/20/2018 at 9:40 AM, Droogne said:

...what would you think about using something like Jack 10 from BillFitzMaurice (http://www.billfitzmaurice.com/Jack.html)

That type of coaxial configuration has worked for Tannoy, Altec 604 (including the "Big Red" of Sherwood Sax), and UREI 809A, etc., of which all were used as studio monitors in the 1960s-1980s. 

 

The devil is in the details, however.  You're right about the MEHs performing better.  But coaxial designs can work very well. There are issues of coverage. Time alignment and smoothing the frequency response I believe needs to be addressed via the use of DSP crossover and bi/tri-amping. 

 

Chris

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5 hours ago, Chris A said:

That type of coaxial configuration has worked for Tannoy, Altec 604 (including the "Big Red" of Sherwood Sax), and UREI 809A, etc., of which all were used as studio monitors in the 1960s-1980s. 

 

The devil is in the details, however.  You're right about the MEHs performing better.  But coaxial designs can work very well. There are issues of coverage. Time alignment and smoothing the frequency response I believe needs to be addressed via the use of DSP crossover and bi/tri-amping. 

 

Chris

Was not planning to use it as a coaxial, but rather just putting the horn (probably the K510) on top of the cab. That way I could still choose my horn and driver, and not be compromised in size. 

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On 1/28/2018 at 6:34 AM, jazzmessengers said:

 

For popular classic rock (ie Allman Brothers, Cream, Grateful Dead, etc) there are actually many audiophile versions of these albums on CD or SACD (with redbook layer) that are pretty damn close to flat transfers from the master tapes or only have 1-3 db of boost/shelf in some frequencies to massage errors in mixes according to the mastering engineers I've spoke to and they never use compression. There was also a series of CD/SACDs released by Universal Japan several years ago that were purely flat transfers of the master tapes with nothing else done to them, many popular classic rock albums were done in this series, there is a huge thread on the Steve Hoffman forum about them. In the liner notes they included the tape source (some albums have master tapes stored in the US some in the UK), mastering studio and mastering engineer name and a few of them verified that they didn't do anything to them per Universal Japan's wishes.

 

I will have a read through Toole again on reflections, guess I misremembered on when the reflections are happening.

 

With regard to surround, I would say at least 95% or more of the music I like is stereo mix only.

 

Rather off the OP's topic but I tried 4 of their (Universal Music Japan) SHM-CD's and was pretty UNimpressed with their dynamic range... actually on the lower end of the spectrum compared to other versions on the DR database.   Now what I bought weren't exactly typical audiophile albums but some rock CD's that I either didn't have and were on my "buy some day" list or I wanted a better version.  Expensive fail for me.  You might say I don't have a "yen" for anymore.  

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