Holographic Soundstage ?


I would like to share my observation and hopefully get some input from people who have the same interest.

My system consist of Wharfedale Opus 3 , Krell KRC-3 preamp, Krell KSA 150 amp, Chord Qutest DAC and a computer with JCAT USB EX running Roon/with LPSU from HDPlex.
I mainly like holographic soundstage and would be able to achieve a very good 3D soundstaging with my current Krell setup.
I decided to try out tube amp a couple days ago because I read through the internet and everybody told me that tube amp always have better holographic soundstage and 3D imaging comparing to SS amp.
So I order a Raven Blackhawk MK3 from Raven audio with 45 days home trial just to try it out. I was expecting a very holographic soundstage that will blow my Krell out of the water.
Well, I was so WRONG. The Krell combo actually has a deeper and wider soundstage comparing to the Raven.
The Raven also has some very weak bass comparing to the Krell which is more punchy and tonally rich textured bass.
I cannot understand why it happens. I am always under the impression that tube amp will always provide more holographic soundstage. Obviously, In my set up the Krell is superior when it come to 3 dimensionality.

I will keeping trying out the Raven Blackhawk in the next couple of weeks and if things are not improved. I am ready to return the Raven and perhaps trying out the other tube amps (or solid state amps) that can beat the Krell combo.

If any one has some idea of such a product, please let me know. I am looking for an upgrade right now.

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I always found imaging was more a function of the speakers.  I've been a planar guy for a long time now, first with Apogees and now with Maggies.  I'm not familiar with your particular speakers so I can't really comment there.

Not my cup of tea, but the Black Ice Audio F360 has a soundstage expander function built in.  Not sure how it does that but it might be an option while keeping your amp.
The idea of tubes being holographic is a broad generalization and is highly specific to the individual component and the result of the whole system. All components matter. .

Yes, keep them for a while, you need at least 200 hours on it before the component starts sounding like it should (usually 400 or more to fully break in)... keep it going when you are awake. But definitely return it if it doesn’t do exactly what you want. In that case you got a chance to really learn about a component in detail. To me it takes a couple weeks of listening to music (not to the system sound) to understand what a component sounds like.
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The end result you want is a perfectly reasonable one. But it is going to take a lot of work... reading, listening at dealers, and experimenting. The sound you are looking for is balancing a system on a knife edge of tonal balance to have enough high end detail but not be harsh and really quite background. The most holographic systems I have heard were based on Wilson speakers... although they by no means are the only speakers good at it. But... it is every piece of equipment and the interconnects that will get you where you want to go.
Your speakers at 91dB are not awful but are below my (admittedly totally arbitrary) cutoff of 92dB that anyone should consider before buying any speaker. But plenty of others are in the same boat and getting great sound so that is not the real issue here. 

I am with you on holographic imaging, it is probably the most compelling thing you can have going for you in a great hi-end system. Only problem, nothing out of the box new has awesome holographic imaging. Instead, the sound you get early on is always out of focus. How much and how bad is relative and all over the map. 

But the good news is if the component is any good- which the Blackhawk certainly is - this will improve rapidly. I doubt you will be waiting any 100 hours for it to impress.

Now in terms of what can make it even a whole lot better, tube amps because of the way they work are particularly sensitive to vibration. The electrons physically travel across a vacuum between metal plates. You can see the darn things in action! The tubes stick up out of the amp. It is like putting something sensitive on top of a pole. Any vibration at the base is exaggerated by being out on the end of the pole. And these metal plates, they are sending and receiving our signal. Obviously even tiny micro vibrations are going to mess that up, big time.

They do. That is why one of the better things you can do is put the amp on Townshend Podiums. I did with mine and the improvement was shocking. Greater image focus, speakers disappear even more, blacker backgrounds, better macro-dynamics, and a lot better micro-dynamics. Subtle details just pop out now, individual threads of instruments are now easy to hear even within complex loud music. 

But mostly I think your Blackhawk just needs more time. Keep playing and see how you feel another 10-20-40 hours from now.
But mostly I think your Blackhawk just needs more time. Keep playing and see how you feel another 10-20-40 hours from now.
I will run the Blackhawk for the next two weeks. Might be they will change. Experience told me that if an equipment cannot impress me the first day or two, it will never do so, no matter how much it will break-in. But, we will see...

"...The sound you are looking for is balancing a system on a knife edge of tonal balance to have enough high end detail but not be harsh..."

Let the amp run in for a few hours, they do gain focus after the new tubes get some hours on them. Also changing the pre-amp tubes can gain good results so if you keep the amp it can be better than it is today. The Krells are good amps so it will take the right tube amp with the right tubes to get up to that level. 
"The idea of tubes being holographic is a broad generalization and is highly specific to the individual component and the result of the whole system. ALL components matter."     Including: good tubes, output power and time in operation (as mentioned by some).
You are comparing a 20 watt integrated amp to the 150 watt krell. You can’t get blood from a stone. The 120 watt Quicksilver mono amps might give you what you are looking for!
http://quicksilveraudio.com/products/mono-120/
Moon 340ix and Sonus faber Olympica Nova 2. I am there but also was a balancing act. 
You only get a holographic soundstage in a holodeck. 
I enjoy holographic imaging, soundstage filling of my room and listener envelopment factor with a 500 bucks system...

Control vibration yes, and decrease electrical grid noise floor...

BUT mainly my results are related to acoustic controls of my room...

Then many factors enter the equations.... But acoustic is one important factor....


Also know that that holographic sound quality is partly due to what's coming out of your source components.

I didn't find the Chord Qutest to be particularly holographic in sound. A Denafrips Pontus II made a big difference for me in changing how my entire system sounds.

Also, using a computer as your source versus a dedicated streamer with a cleaner signal could have an effect as well.
Tube amplifiers are very speaker sensitive and it is obvious that the wharfedale speakers are not good on a tube amp if you hear weak bass and a loss of dynamics you will have to go to a large tube amplifier to be able to drive them and at that point you will drop a ton of money and the soundstage may not be as good as what you have now tweaking your setup will probably make your sounstage better than upgrading your equipment and will pay of with bigger dividends in the long run.
If using a computer the Jcat Ethernet cable is by far the best card for Roon or QA Buz  ,the Jcat usb is good if using your hard drives wav or flac files .
Using the Ajcat Usb,and Ethernets cards ,shut down and isolate the computers functions and noise and using a good linear power supply is a big upgrade 
many streamers unless $$ are cheap and use switch mode power supplies 
heat pipe ,and SS drives are a huge plus also. I have custom voltage regulators ,Mojo  Audio sells with all needed wires a instant  upgrade .
Experience told me that if an equipment cannot impress me the first day or two, it will never do so, no matter how much it will break-in.
If that was the case I would’ve returned my speakers.  That was about 20 years ago and I still have and love those same speakers that sounded awful for at least 100 hours.  Suffice it to say my experience is very different as I suspect yours may be with the Raven.  There’s a reason they give you 45 days.  Patience. 

Another direction to go for depth of sound stage specifically: audiokenesis sound generator horns... rear-firing add-on speakers: they work (in my system).
Another direction to go for depth of sound stage specifically: audiokenesis sound generator horns... rear-firing add-on speakers: they work (in my system).
For sure they are based on the "timing" between late and early reflection and particularly back reflection...

But it is possible to use the right material passive treatment and the right active controls with Helmholtz resonators at no cost to generate this space....Without speaker addition....But it is less esthetical...

I prefer solution at no cost anyway...  😊

A Carver C-1 preamp with BillD mod or a C-9 will make any system's soundstage wide and deep with sonic holography. 
Go buy a pair of tannoys If you want holographic...I use mine with class A solid state, sugden. However, I am also using a tubed phono stage, Tavish. I do not get a holographic sound stage with everything I play, however, It does happen often. 
What ought to be the minimum dBSPL speaker for a 7 watt 300B single ended amplifier please.
Thank you.
Go buy a pair of tannoys If you want holographic...I use mine with class A solid state, sugden.
it was my gear for 15 years !...

What people name holographic impression exist...

The problem is the level of holography...

!0 or 25 % and the people say: i have holography...

But it is my experience and experiment with acoustic and psychoacoustic....

You need to controls vibrations of the speakers, electrical noise floor of the house and ESPECIALLY acoustic control not only material passive treatment...bUt the room with active Helmholtz resonators...

I am sorry for the bad news...

The good news is you have an idea of holographic with this pairing because the Tannoy dual concentric were even better than what i own now...

But what i have now is under acoustic control and give me more than the Tannoy even if it is a notch under their quality...

Acoustic is the most important tool in audio .....
MillerCarbon is correct, wait for the system to settle down and the new items to break in. After 300 hours you will have a good idea of what to expect for performance in the future. Patience
Here's one formula for a big soundstage with holographic imaging:

1. good recordings (ideally binaural, but good luck finding them for music you like)
2. highly directive (focused) loudspeakers, such as Sanders, JansZen, or some KEF models ... or, alternately, a combination of room treatments and effective placement of the speakers you already have
3. crosstalk-minimizing DSP software (BACCH or possibly HAF)

BACCH4Mac would cost you about $1K (plus the price of a Mac if you do not have one) for the "intro" version.  The effects can be quite dramatic (on some recordings more than others).  For example, a performer who seems to be playing out of your left loudspeaker, pre-BACCH, might seem to be playing several feet to the left of the loudspeaker, post-BACCH. The developer (a physics professor at Princeton U.) claims that these effects result without otherwise coloring the sound signature. A trade-off is that the effect mostly occurs only within a very narrow sweet spot (which can be a show-stopper for some people.)

Short of DSP software, I would think your biggest bang for the buck comes first from proper speaker setup (which can be cost-free) then room treatment. Then gradually building up a library of excellent recordings.

I found my tube amp performed much better once I got a power conditioner. I have horn speakers which helps with the imaging as well . Your tube amp might be underpowered  for the efficiency of your speakers this might explain lack of bass. I'd try the power conditioner I got one for like 600$ that made a world of difference. 
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You want a nice holographic soundstage? Here is what I do for my listening position...... you will never do this and any audiophile snob reading this will pan it for sure..... but if its soundstage you want, as far as I am concerned, no amount of money on just the right tube amp or Tannoy this or Helmholtz that, will give you an incredible, speaker disappearing soundstage than the following...... ready? Go on to ebay and spend the $150 to $200 on a vintage 1980's Carver C9 Sonic hologram generator and introduce THAT into your system. My 20k 2 channel system loves it and I consider this the most important piece on my rack. There, I said it, now don't do it because you will be laughed at for thinking you could achieve this without spending 5k somewhere and especially because you are using something old and used from the 1980's and how dare I suggest something that is not refined and tweaked to todays standards.....  fine........ you are missing out on what you are looking for. It is amazing but you wont spend the $150 to find out. 
There is a piece of gear that has the specific objective of giving you a more holographic soundstage. It's a processor from a company called BSG (no longer in business) and the model is a QOL (pronounced coal). It has been positively reviewed by Stereophile and TAS and the reviews are available on their websites. When new they sold for $4k which I believe is a large reason why they didn't catch on. You can occasionally find one on the used market for under a grand.

I have one in my system (Krell KSA 300S, KRC-2, Theil CS6 speakers) and I really like the effect. An audio buddy recently stayed at my house for a couple days and he was very impressed by the depth of the soundstage and the placement of voices and instruments. When bypassed, the difference is very noticeable. I use it nearly all the time. Once in a while I encounter a recording that sounds worse using the QOL but that's pretty rare.

If you can find one I highly recommend trying it. If you don't like it you should be able to resell it for nearly what you paid for it so it's a low risk proposition. I like mine so much I bought a second one in case the first one quits working.
You just described my experience with the Carver C9 perfectly (except for the part about finding a rare recording where it does not sound good; havent found that yet), all the way down to owning a backup. I own 2 backups for the same reason. me main one has been re-capped refurbished by a gut in the midwest somewhere that does this.

I am very intriqued by the BSG unit and will look it up. We are definately on the same page. Defined instrumentation to the left and right of the speakers and everything in between including an untouched center stage between the speakers is heaven for me.

Is the BSG unit using a phase type processing similar to the Bob Carver unit?
Along with a few others' posts I really suspect your speakers are underpowered with the Raven. Loss of bass and scale is what happens with underpowered speakers. Wharfedale recommends 100-600 watts. Further, watts-sensivity-listening distance calculation is an incomplete approach in selecting speakers or amplifiers in my experience. Most recently my 94db speakers have been underpowered with 80 watts and 150 watts. Only 300 watts was able to control their large woofer. It was a big difference. This is in contrast to my older ~87db speakers for which 75 watts was just fine. 
Might be hard for you to do during a trial. When i rolled out new tungsol tubes for 1953 sylvinia  bad boys the 3d sound jumped out. Second fix that really opened my soundstage was moving from wifi to ether net cat7 hard wire for my quobuz. Then added fiber optic cable for last leg and now i am at 4d. People say it sounds like the singer is closer to them than the drummer and the right left separation of guitar players is mind blowing. Bass is tight and upfront with kick drum. So don't give up but again it is hard to drop $150 on a tube to try it out.
shreg1, your argument for cat 7 and fiber vs wifi making any difference in sound is pure imagination. 
The most 3D speakers I have ever heard, are my ESL-57's.

Limitations? For sure! (Everything has it's limitations...)

I was listening to them when I first got them after having built some new legs for them and getting them set up "properly".

Was listening to "Jazz at the Pawnshop", a piece I was not particularly familiar with. The audience can be heard chatting, clinking and bustling in the background. At the beginning of the record, I actually turned around to see who was in my room, looking over my left shoulder convinced I had heard someone there. Nope, was the background sounds of the audience. The soundstage was just crazy, have never experienced anything like that before. Full 360 degree "Soundarama Soundstage" 
I always found imaging was more a function of the speakers


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WOW alot of posts up above i have yet to read. 
But anyway, I agree here, speakers is the actual voice to the other components. 
So the idea of 
~3D~
I interpret as 
Soundstage/width/depth, life like vocals. Muddy mids eliminated, not too *warm* which to me is distortion, likea  layering effect.
The Gold Lion KT88's were too warm in my amp = less soundstage, or if you wish ~3D effect~.
The term in the old days as coined by Philips ~High Fidelity~.
Tag it anyway you wish. 
I perfer the old standard termonolgy
~High Fidelity~
With the right speakers, all other components and the tewaks such as new  botique caps, resistors, wiring/cables , can work in their effects on total sound. 
If anyone says high end caps are just as good as low priced caps, is wrong. \
I've made this experiement and  can assure you, higher end caps, make a  nice nuance gain.
Also know that that holographic sound quality is partly due to what's coming out of your source components.


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Well yes, I just added a  Philips 777 phono to my sources. Phono is superior to cds, but my classical collection is mostly cd releases. I am adding LP 's lately and can concur LP's do  possess a  ~3D~ which digital cds  lack, Not sure about the new high bit streaming, which i am not interested in. 
Source used will affect for better or worse...
Also most of my classical cds are not super high resoltion/studio engineered recordings, take this into account, But then also some jazz cds tend to lack that sparkle, such as Diana Krall, tend to be a bit rough in dynamics. 
I think the  1960's,  early 1970's recordings were best sound quality. 

In classical, some EMI and Philips recordings suffer from poor studio  recording. 


Holographic is easy with 4 Walsh....2 front, 2 rear, with judicious level and balance control.

One doesn't need to get too deep into room acoustics and the treatment issue, either.
@ mikekollar

I also have a C9 and I've compared the two processors. I prefer the BSG because the effect covers a wider listening area. You can be sitting a couple feet to either side and you still get the soundstage effect with the BSG but with the Carver you have to be right in the sweet spot. When you are in the right position, the Carver has a somewhat greater effect than the BSG. For everyday listening I like the effect of the BSG somewhat better but the Carver is an excellent processor.

The BSG designer was sketchy about exactly how the processor works but apparently it separates the music into separate bands and applies the phase modification (or whatever) differently to each band. It's a pain to compare the processed signal to the bypassed signal because the processor adds several db of volume which is one feature I definitely don't like. There is some decent information in the review articles but they don't really explain how it works.

On a side note, I heard a demo of Synergistic tweaks at the 2018 AXPONA and was blown away by their Atmosphere thingy (the speakers were upper-end Magicos). It is a narrow square column that sits between and behind the speakers. I couldn't hear any difference from the HFT gizmos but when he turned off the Atmosphere the soundstage collapsed. I can't understand how it works from looking at their website but it certainly had a noticeable positive effect.
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Interesting..... thanks....
Interesting, I will have to look at these processors. What I can say about the carver c9 is this. My Emotiva pre amp has an external processor loop. That is where I have the c9 so it enables me to switch in and out from my listening position and your choice of words are exactly how I describe the c9. When it is turned off, the soundstage absolutely collapses. And when it is on, there is absolutely no degradation in sound quality, just a much larger soundstage that goes outside of the 2 speakers. To hear exact instruments and echoes and all, on the far left and right, with a vocal still dead center is amazing, and yes, the sweet spot, unfortunately, is only for one person, however, the effect is there for two people if one is sitting directly behind the other.

For me, it does not matter as critical listening is a very personal one to one relationship, at least in my household. What really blows me away is all the discussion about this amp or that, This dac or that, vinyl or digital, chasing with big bucks the next incremental little improvement; and non of it..... repeat NONE, has the sound quality enhancement and difference of the listening experience as the C9 (or similar apparently), and all of this for about $200 or less. (oh yeah, don't do it.... your Mcintosh would be offended.

I run my music from a node 2i into a mini dsp dac and Dirac Live processor then on to the c9 where we then go bi amped to a pair of 14K Legacy Focus XD towers. So its not like I have terrible stuff; its not the best, but better than most. It sounds amazing. And one other thing about this kind of processing.

 It's almost scary when a recording has sounds coming at you at 45 degrees away from the center channel. Literally straight in from the left and right. (try Madonna - Vogue for that one). So for my sound stage processor friends, I came across a recording that when used with the C9, I heard the largest soundstage of any recording ever and in a way that I have never heard before.

The artist, F.K.A. Twigs. The song, Pendulum. This song has sounds from a huge sound stage plus.... sounds moving back and forth above and behind my head. No recording has ever done this for me and it is mind blowing. It's weird, but listenable music, not my favorite, but whatever the recording engineer did on this track is freaky when it comes to listening with a carver c9 and I'm sure with your BSG. Literally, the sound is NOT coming from the speakers!!!!! Or so it seems. Check it out.
The artist, F.K.A. Twigs. The song, Pendulum. This song has sounds from a huge sound stage plus.... sounds moving back and forth above and behind my head. No recording has ever done this for me and it is mind blowing.
I am very interested by this discussion...

I just listen, writing this, to this files "pendulum"... Thanks.... 😊

I Listen to the same sonic experience than you...

But i dont own a carver nor any holographic processor...

I cannot compare for sure my experience with yours...

But it mimic completely your description...

My system is average and good...

But i a devised mechanical equalizer, with discarded materials from my basement, which use each direct front wave of each speakers asymmetrically, i had the tweeter of one speaker near two of my Helmholtz tubes and the bass driver of the other speaker near three Helmholtz other different tubes.... I distribute 32 tubes and pipes with variable and orientable neck in precise locations in the room .. I am very proud of this creation i stumble on psychoacoustic research paper about timing thresholds experiments and that give me the idea....

My room is already treated by me with passive materials with reflective and absorbing and dispersive surfaces, all homemade.... The ears guided me.... It take a long time tough to reach a good balance.... But listening experiments was fun...

I fine tuned them by listening on a month period, like fine tuning a piano...

There is no comparison between before and after...

I am glad that reading your post and trying this file that confirm my experiment with room controls...

I cannot say that my listening correspond exactly to your experience but your description fit mine...

I never bought anything nor any tweaks, i was not loose in money and created all my devices homemade with basic psychoacoustic facts for room controls...

Amazing file thanks...

Try this opera.... You will be surprized by the genius of the recording engineer.... I see the singers walking and turning their heads while singing  in the studio.... And Often their voices come completely from my back .... They walked singing all around me....


The youtube file is better than average youtube but it is better with the original for sure...Anyway you can use the youtube to test your carver...

https://www.youtube.com/watch?v=qR33bL5aNTk&list=PLnQJF3Qi_4_CvjtOvZypmfmC4ygxSxOgm&index=53&t=95s

Let me know of your experience with this opera if you will.... Thanks
It’s almost scary when a recording has sounds coming at you at 45 degrees away from the center channel. Literally straight in from the left and right. (try Madonna - Vogue for that one).
Same experience with the Madonna thanks....

My speakers are smaller than yours....My room is 13 feet squared but irregular.... With a difficult position of the speakers it takes me time to correct...   Mission Cyrus 781.... Very good but not pricey speakers....

For me acoustic matter more than speakers if the speakers are "relatively good" for sure....

Regards...
A little late to the party here...  I am a big fan of Pass Labs equipment; this holographic imaging you are speaking of is in abundance with a good spec Pass line stage.  I have a 3 box Pass line stage (X0.2) connected to my Aleph 1.2 mono blocks (250 w/ch class A).  Let me tell you, hah!  Now, the newer Pass line stages like the XP-22 and XP-32 are supposed to be terrific; I seem to remember the XP-22 landed an best of something award from Stereophile a few years back.  Next, I've listened to Audio Research line stages in the Ref 5, 5 SE and 6 SE variety, and all I have to say is woahhhhh.  These are very nice. Go to a brick and mortar store that sells Pass and ARC equipment, bring your most favorite discs or music on a DAP or thumb drive.  Listen to it then buy.  Happy hunting.  
Rifraf4u
What i hear is no imagination and simple to figure out. Wifi can only transfer so much data and as it travels through walls ceilings floors and electrical fields that data is compromised. Hard wire does not have thst issue so when the data reaches the dac there is more clean data (sound) coming through.
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@mikekollar - "Go on to ebay and spend the $150 to $200 on a vintage 1980's Carver C9 Sonic hologram generator and introduce THAT into your system. My 20k 2 channel system loves it and I consider this the most important piece on my rack."

Yep, companies have been adding an out-of-phase signal (crosstalk cancellation) for decades.  Lexicon did it in their processors, Polk did it with their SDA speakers and right now there is a VERY well liked speaker line that uses tweeter arrays in the same way - feeding some of the tweeters out-of-phase signals to achieve some great sound. So I'm not shocked your Carver C9 is your most loved piece of gear in your $20k system. Bravo for even bringing it up since you know what happens on these boards......
Why not trying to recreate this "headphone effect" about imaging and listener envelopment (LEV) instead of using electronical cross talk control with a mechanichal acoustic control?

It is possible if i have it....

For sure 32 helmholtz pipes and tubes in a living room and some devices near the tweeter of one speaker and the bass driver of the other one are not esthetical either....

But all my 7 headphones are in the drawers definitively.... 😊

I can control "timbre perception experience" with my grid of Helmholtz devices, not only soundstage or LEV, could i with an electronical Carver c9 ? The experience of a more natural timbre perception is more important for me than anything but a system without holographic imaging filling the room is without appeal at all...Speakers must vanish in a good system....

In fact an out pof phase signals added will not make us able to control or correct the timbre experience in a specific room.... Then..... It is only an artificial device for the imaging and soundstage perception... It is not enough if your room/ speakers are not totally already adapted  and able to give you a natural "timbre" experience already...My grid give me that.... Passive material treatment of my room was not enough...there is a relation between the acoustic factors linked to timbre and imaging and soundstage.... It is difficult to reach the right timing of the wavefronts to the ears....But with my grid the "tiniest" tuning is possible...

This is a low price device the carver c9 indeed, and i am curious to try one if i could look for one some day, but after what i experience now, it seems i dont need it at all...
@sgreg1 that is not how it works.

Also It’s not unusual for tube amps with higher output impedance ( than SS in general and Krell) to have relatively less articulate bass and inferior dynamics as it interacts with the speaker load at various frequencies. Distortion is likely much higher in that case than with a comparable SS amp of lower output impedance overall. This is why impedance matching matters.
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Because you don’t have it. You may think you do, but you do not. No matter what you do with acoustics, you cannot do what is required to accomplish this. Time to learn more about this before typing. You will save a lot of typing.
I know that you are more knowledgeable than me and most in audio by a more than a small margin...

I hope that in spite of our different perspectives you smell the difference between me and some others....

BUT instead of explaining why i am supposed to be deluded you dismiss my experience...It is not enough....Sorry....We do not discuss "directed wiring" here... But the relation of acoustic with improvement of perception and the use of mechanical distributed Helmholtz resonators versus electronical means...I dont pretend that my solution is perfect it is not... But efficient at no cost it is....




I just listened the same files someone here proposed like a test and i lived the same perceptive experience or something near it because i am not frustrated about what he described and what i experience...

my remarks are only linked to a question: what acoustic control can do on par or better than Carver c9 ? it is a question but i had the impression that i lack nothing about all acoustical factors which other described.... I even prefer my grid to the synergetic research processor i listened to on many video on youtube....Anyway my ratio S.Q. /price is very high compared to them .... 😁

Explain to me why not? instead of dismissing without justification....

By the way my grid of Helmholtz resonators are not distributed randomly and i used the tweeter wavefront of one speaker and the bass driver of the other speaker to help my ears recreate the sense of space.... And contrary to a crosstalk control device i can work with "timbre perception" .... In my acoustic experience all factors like imaging, soundstage, LEV, are all linked in a kind of acoustical trade-off which i control with fine tuning mechanically the volume/neck ratio, the length.... It is not perfect but spectacular and sound natural to me....