How holographic can a soundstage be?

[Blaspheme]

I have Sitara 25's bought last year, upgraded from Yara 2 Classics. I tried larger AP's but my dedicated room is small (3.2 x 4.5 m) and bass was a problem especially from side firing woofers. I now use 2 subwoofers and block the ports on the Sitara's. This seems to suit my Vincent pre power amps and keeps all my listening within the class A range, they switch to AB at 10+ watts? I constructed large bass traps and added diffusion elements in the room, an enormous recliner also helps to suck bass and prevent rear reflections. Very happy especially since upgrading to Denifrips Aries II Dac. Exceptional soundstage for a small room.

Interesting, looks like your system is set up very nicely. Adding subwoofers to Sitara was of course my original plan. I expect it works rather well (AP use versions of the same tweeter and mid across the reference range as you'd know). Good idea to try blocking the ports. Out of curiosity, what size/type subs did you use?

I ended up with AP's newer down-firing method rather than the woofers on the side. Some say it's easier to integrate the bass/position the speaker with the former but room modes are room modes and there's no avoiding them really. And separate subs can be advantageous: effectively I have mains and subs—imagining Codex as three way with a built-in passive sub crossing at 100 Hz—locked in the same position (now I have them slightly wide with toe-in facing the listening position exactly). The room envelope is a bit larger than yours (roughly 4.5 x 6.5 m) so the first long modes are around 25 and 50 Hz—the latter gives a big bump which I have to tame with DSP via Sonarworks. That's with them quite close to the front wall, I'll be able to position the speakers better when renovations are done. The room acoustics aren't bad by virtue of architecture and materials providing some absorption and diffusion higher up. I haven't employed additional room treatment yet. Did you post anywhere about your bass trap and room treatment process?

Btw I liked the Sitaras aesthetically and sonically so didn't trade them in in the end, instead kept them to try multi-channel or a second system some time down the track.

 

[Deleted member 24508]

Interesting, looks like your system is set up very nicely. Adding subwoofers to Sitara was of course my original plan. I expect it works rather well (AP use versions of the same tweeter and mid across the reference range as you'd know). Good idea to try blocking the ports. Out of curiosity, what size/type subs did you use?

I ended up with AP's newer down-firing method rather than the woofers on the side. Some say it's easier to integrate the bass/position the speaker with the former but room modes are room modes and there's no avoiding them really. And separate subs can be advantageous: effectively I have mains and subs—imagining Codex as three way with a built-in passive sub crossing at 100 Hz—locked in the same position (now I have them slightly wide with toe-in facing the listening position exactly). The room envelope is a bit larger than yours (roughly 4.5 x 6.5 m) so the first long modes are around 25 and 50 Hz—the latter gives a big bump which I have to tame with DSP via Sonarworks. That's with them quite close to the front wall, I'll be able to position the speakers better when renovations are done. The room acoustics aren't bad by virtue of architecture and materials providing some absorption and diffusion higher up. I haven't employed additional room treatment yet. Did you post anywhere about your bass trap and room treatment process? Typical engineer so sorry about long answer?

Btw I liked the Sitaras aesthetically and sonically so didn't trade them in in the end, instead kept them to try multi-channel or a second system some time down the track.

I made bass traps experimentally, having worked in munitions manufacturing and studied the topic at Sydney uni I have some experience in sound absorption, however in munitions manufacturing that is usually for high to mid frequencies. I eventually found that the traps I made of cardboard filled with absorbing material to fit in an Ikea Kallax system were effective. You can actually feel and measure the sides and back of the cardboard boxes vibrate at around 55 / 60 Hz. These are around 750 mm thick filled with different layers of absorbing material, thin one were next to useless. Also placing them away from the walls a little means any sound going through must hit the wall and them return through the 750 mm again. I use two Definitive Technology Supercube 4000 set at 65 Hz. The Vincent pre amp allows me to attenuate bass. So blocking the ports and attenuating the bass to the speakers means they are not competing with the subwoofers, it also means my power amp needs to work less hard certainly below its 10 watt class A output crossover point. The rest of the room I have used paintings and objects for diffusion, placed thinner (50mm) soft material bass traps hidden behind curtains to lower reflections from glass etc. Of course all of this is in a dedicated room so no WAF issues. I am currently building purpose built cabinets to hold the bass traps. The Kallax is just too big and presents problems siting it effectively. Speakers and subwoofers are roughly 950 mm from the back wall with subs on stands making bass cones at approx same height as subs, this assists with interaction between the bass and the floor. I had the room purpose built so the rear wall has a double wardrobe filled with things that absorb and deflect, opening or closing the doors has a marked effect, so much so that at certain angles the doors will vibrate ( at 60Hz) Lastly to prove how anal you can get I installed a large ceiling fan at the first reflection point above the speakers not really sure it does anything but it does keep me cool. Interestingly they use the same technique at the Sydney Opera House where halos are placed above the orchestra to diffuse and reflect sound away from the notoriously bad acoustics of the building. ( Studies at uni in Sydney when I was on an acoustics course there in the early 1980's went into the topic and the solution in some detail, so could not control my need to replicate?). Have fun, for me having tried lots of speakers from a couple of friendly hifi stores and from friends the Sitara's are close to ideal as far as I can tell. They are small enough and the bass, with my experimentation, is restricted enough, to allow me to use subs very effectively. They seem to now fit sort of right between being an effective large bookshelf and a small floor stander in terms of their output and dynamics. I found anything larger dominated the room and I could not control the bass at 55/65 Hz.

 

[Blaspheme]

I made bass traps experimentally, having worked in munitions manufacturing and studied the topic at Sydney uni I have some experience in sound absorption, however in munitions manufacturing that is usually for high to mid frequencies. I eventually found that the traps I made of cardboard filled with absorbing material to fit in an Ikea Kallax system were effective. You can actually feel and measure the sides and back of the cardboard boxes vibrate at around 55 / 60 Hz. These are around 750 mm thick filled with different layers of absorbing material, thin one were next to useless. Also placing them away from the walls a little means any sound going through must hit the wall and them return through the 750 mm again. I use two Definitive Technology Supercube 4000 set at 65 Hz. The Vincent pre amp allows me to attenuate bass. So blocking the ports and attenuating the bass to the speakers means they are not competing with the subwoofers, it also means my power amp needs to work less hard certainly below its 10 watt class A output crossover point. The rest of the room I have used paintings and objects for diffusion, placed thinner (50mm) soft material bass traps hidden behind curtains to lower reflections from glass etc. Of course all of this is in a dedicated room so no WAF issues. I am currently building purpose built cabinets to hold the bass traps. The Kallax is just too big and presents problems siting it effectively. Speakers and subwoofers are roughly 950 mm from the back wall with subs on stands making bass cones at approx same height as subs, this assists with interaction between the bass and the floor. I had the room purpose built so the rear wall has a double wardrobe filled with things that absorb and deflect, opening or closing the doors has a marked effect, so much so that at certain angles the doors will vibrate ( at 60Hz) Lastly to prove how anal you can get I installed a large ceiling fan at the first reflection point above the speakers not really sure it does anything but it does keep me cool. Interestingly they use the same technique at the Sydney Opera House where halos are placed above the orchestra to diffuse and reflect sound away from the notoriously bad acoustics of the building. ( Studies at uni in Sydney when I was on an acoustics course there in the early 1980's went into the topic and the solution in some detail, so could not control my need to replicate?). Have fun, for me having tried lots of speakers from a couple of friendly hifi stores and from friends the Sitara's are close to ideal as far as I can tell. They are small enough and the bass, with my experimentation, is restricted enough, to allow me to use subs very effectively. They seem to now fit sort of right between being an effective large bookshelf and a small floor stander in terms of their output and dynamics. I found anything larger dominated the room and I could not control the bass at 55/65 Hz.

Good to see someone taking Kallax-Fi seriously.

So I'm guessing the Kallax currently hold the absorber boxes which extend out the back ~400 mm or so. I have been dreaming up ways to get sufficient absorber depth to treat those lower modes. How many—boxes, not Kallax —did you deploy? I guess there are several Kallax configurations too, is/are yours 4x4? Also, was there a logic to the material layering?

I hadn't come across those subs before, they look clever.

Finally, yes I bought Sitara originally after listening to and liking Step 25 but wanting a bit more bass. A demo pair was the same price. Also, no need for stands. I thought they might integrate better with subs as well, that being the plan from the start. Plugging the ports probably addresses their slightly warm/elevated mid-bass (in my room anyway). Interesting that I didn't notice the 50 Hz room mode (as a negative) until I tried the larger speakers. I also have a strong null (looks like combination of modes, lateral and oblique, although my room is harder to model with a sloping ceiling) around 80 Hz which affected both speaker models the same way. Moving them closer to the side wall flattens it, but a series of higher modes takes hits out of the mid-bass.

 

[Deleted member 24508]

Good to see someone taking Kallax-Fi seriously.

So I'm guessing the Kallax currently hold the absorber boxes which extend out the back ~400 mm or so. I have been dreaming up ways to get sufficient absorber depth to treat those lower modes. How many—boxes, not Kallax —did you deploy? I guess there are several Kallax configurations too, is/are yours 4x4? Also, was there a logic to the material layering?

I hadn't come across those subs before, they look clever.

Finally, yes I bought Sitara originally after listening to and liking Step 25 but wanting a bit more bass. A demo pair was the same price. Also, no need for stands. I thought they might integrate better with subs as well, that being the plan from the start. Plugging the ports probably addresses their slightly warm/elevated mid-bass (in my room anyway). Interesting that I didn't notice the 50 Hz room mode (as a negative) until I tried the larger speakers. I also have a strong null (looks like combination of modes, lateral and oblique, although my room is harder to model with a sloping ceiling) around 80 Hz which affected both speaker models the same way. Moving them closer to the side wall flattens it, but a series of higher modes takes hits out of the mid-bass.

Sorry made an error bass traps are 350 mm not 750 mm. I started off making them to fit in 4x4 Kallax, so my plentiful supply of wine boxes got used, but could not then put the Kallax in the best place, currently have them freestanding in corners of room slightly away from corners. I made 4 boxes at 350 and 2 at 175 deep, each of the numerous pictures have the insulation in the back for dampening, that used up all my available material. I had the walls of the room filled with Bradford high density insulation and I used this with 2 other layers of thick foam in each box. Replaced the Kallax with a DIY solution which has diffusion and defraction elements built in, wooden selves , chrome steel legs create lots of angles, now building boxes for base traps and CD rack for top with similar principles. Material layers start with least dense gets more dense. Subwoofers stands are sand filled and used washing machine vibration isolators between subs and stands.

 

[Blaspheme]

Sorry made an error bass traps are 350 mm not 750 mm. I started off making them to fit in 4x4 Kallax, so my plentiful supply of wine boxes got used, but could not then put the Kallax in the best place, currently have them freestanding in corners of room slightly away from corners. I made 4 boxes at 350 and 2 at 175 deep, each of the numerous pictures have the insulation in the back for dampening, that used up all my available material. I had the walls of the room filled with Bradford high density insulation and I used this with 2 other layers of thick foam in each box. Replaced the Kallax with a DIY solution which has diffusion and defraction elements built in, wooden selves , chrome steel legs create lots of angles, now building boxes for base traps and CD rack for top with similar principles. Material layers start with least dense gets more dense. Subwoofers stands are sand filled and used washing machine vibration isolators between subs and stands. View attachment 140763View attachment 140764

Got it, thanks for the detail. I expect I will get to the extra room treatment stage eventually (the kitchen has to move first).

 

[mieswall]

I've had the Audio Physic Virgo 2, Libra and Scorpio in my room, and have listened to various other models. They really do a "disappearing/soundstaging" act like few other speakers. Really a sonic characteristic of the brand.

In the late 90's I heard the Virgos in the nice Sound by Singer store for a several hours, with a monstrous 300B-based amplification ( I can't recall exactly which amp it was). Me alone for as long as I wanted in a careful setup of those speakers prepared by the salesman with a pile of some of my favorite CD's. That tangible "musicians are right here" experience has been one of the most shocking hifi experiences I have ever had; I immediatly fell in love with this brand. I bought Magnepans though, those incredible Audio Physic were out of my budget.

Decades later, I was finally able to get here (in South America) a pair of AudioPhysics some time ago, and most of that imaging/soundstage is back again (not all, since it is a much cheaper model: a Classic 20). That said, my KEF Metas (and before that, the LS50) holography is even better. Just amazing, perhaps as realistic as those original Virgos. They really recreate a virtual reality experience. Btw: that disappearing act is also shocking in mono recordings: several times with good mono recordings I just can't believe the sound is coming from those little boxes and not from a hidden speaker in the middle, even knowing that it is otherwise. Holography is, in my opinion, one of the most important factors in a truly hifi experience. Having listened many high end speakers, hardly any other I've listened has been even close of what the AP's or Meta's can achieve.

Anyway, in both cases the key issue has been to place the speakers as far as possible from back and side walls, with the sweetspot in a equilateral triangle, imho. In my case, the back wall is several meters behind, with both short walls are covered with a bookshelf; I guess that helps to maintain this highly focused sound at that sweetspot. It is an immense pleasure to sit and have a Pauline Oliveros-like deep listening experience that way. Which I do almost every day.

Regarding bold holographic listening experiences, most ECM's in MQA are commendable: you can focus in the pinpoint placement of each instrument or even its individual components (hats, cymbals, etc) without any doubt. Also Tim Hecker's albums (Haunt Me, Do it Again; Harmony in Ultraviolet, etc) are spectacular in this. The Italian percussionist Andrea Belfi records (Wege; Ore; etc) also have amazing spatiality. Among many, many others, of course.

 

[Deleted member 24508]

I have 2 pairs of Audio Physic speakers and they both have great soundstage and imaging, especially so with my Sitara 25's. I use class A (up to 10 watts who needs more) Vincent pre / power tube hybrids which also seem to help. They are generally not the easiest speakers to drive, mine are both 89dB and 4 ohms, so lower powered tube amps seem to dither a bit in the bass, especially upper bass. I do use 2 subwoofers but that is more about controlling bass in a very unruly room. I have tried many speakers but don't like (being diplomatic here) horns, cannot seem to get any soundstage with electrostatics etc (room too small I think) and find dual concentric speakers soundstage generally narrow and wooly in a small space. I think the best AP's, for soundstage, are the speakers without side woofers but bass does suffer in these designs, hence Sitara 25's with subs. Try them if you like detail, soundstage and imaging especially with jazz.