[doggie]

Spatials love tubes.  I run an el34 based LTA Reference 40 Plus, with a Don Sachs all in preamp, and a Musical Paradise MP D2 MK3 DAC with NOS tubes.  I'm presently running the finest system I've ever had.  Just stunning.

+1 for tubes. I think that they bring out the best in the AMT tweeter. I use a LTA Ultralinear Integrated amp and a Lampizator Baltic 3 DAC. Tube rolling has allowed me to really get the sound I am looking for. The LTA amp seems to have the pluses of both tubes and SS. It is also dead silent which is great with 97db speakers.

[DBT AUDIO]

You are most welcome.  I only rewrote it 800 times (LOL).

Marcus

LOL…. I believe you.  We are so passionate about this hobby that we treat it like a job assignment at times!

[Desertpilot]

SBIR and acoustic treatment.

A few days ago, I had to remove my GIK panels from my front wall temporarily.  I decided to leave my front wall bare for listening.  While not dramatic, I did feel that my speakers were not sounding as good.  The highs sounded a bit harsh and the bass a bit muffled.  I decided to research SBIR (Speaker Boundary Interference).

First up is an Audioholics video discussing this topic in detail https://www.youtube.com/watch?v=eXfpAn3gkGs.  The subject was Gene's tower speakers.  Lots of great information in this video, especially about full range tower speakers.  We know OB speakers have excellent side cancellations.  I don't know the scientific impact of OB front wall reflections (SBIR).  The two acousticians (Poes & Grimani) greatly prefer bookshelf speakers for soundstage & imaging and separate subwoofers more ideally placed for bass.

Next up is a GIK video on speaker positioning and SBIR, https://www.youtube.com/watch?v=T10_MLGOBfc.  It argues that speakers should be at least 4 feet from the front wall to greatly lower the SBIR frequency (my speakers are 5 feet from the front wall).  I think with the panels removed (not measured) that I was indeed experiencing some phase cancellation.

Lastly, using GIK Alpha diffusor/absorber panels (which is what I own), https://www.youtube.com/watch?v=seZyhcf1U3g.  This short video argues that diffusors work mostly on mid-range (I did not know this).  Also diffusors should be directly behind speakers (I always thought this was true).

I put my panels back along the front wall.  A GIK bass trap (2 foot by 2 foot with a range limiter) on the floor behind each speaker's subwoofer.  Next, I reoriented my 6A Alpha panels horizontally (I previously had them vertical to cover the AMT driver).  These are placed on the front wall directly behind the mid-range driver.  Results?  Whoa, huge improvement in sound.  Bass is much tighter.  The mid-range (where most of the action happens) was also greatly improved.  Instruments and vocals were less harsh and clearer.  Even my wife noticed the improvement.  I have diffusor/absorber panels on my rear wall as well.

This was an interesting (and useful) exercise for me.  The X3s are a very forgiving speaker but room treatments are important for best results.

Side note:  I am using my older SVS Ultra Bookshelf speakers (with the GR Research crossover) as my rear surround speakers.  They are 87dB sensitivity while my X3s are 97dB sensitivity.  Gain matching all five speakers has been very difficult.  I accidently stumbled on a thread in the Digital Amplifier circle that discussed this issue.  The author said that moving the lower sensitivity speakers closer to the MLP would greatly improve gain matching.  Guess what?  After moving them half the distance closer, I was much better able to gain match them and now I can hear the ambience sound coming from them.

Marcus

[rooze]

SBIR and acoustic treatment.

A few days ago, I had to remove my GIK panels from my front wall temporarily.  I decided to leave my front wall bare for listening.  While not dramatic, I did feel that my speakers were not sounding as good.  The highs sounded a bit harsh and the bass a bit muffled.  I decided to research SBIR (Speaker Boundary Interference).

First up is an Audioholics video discussing this topic in detail https://www.youtube.com/watch?v=eXfpAn3gkGs.  The subject was Gene's tower speakers.  Lots of great information in this video, especially about full range tower speakers.  We know OB speakers have excellent side cancellations.  I don't know the scientific impact of OB front wall reflections (SBIR).  The two acousticians (Poes & Grimani) greatly prefer bookshelf speakers for soundstage & imaging and separate subwoofers more ideally placed for bass.

Next up is a GIK video on speaker positioning and SBIR, https://www.youtube.com/watch?v=T10_MLGOBfc.  It argues that speakers should be at least 4 feet from the front wall to greatly lower the SBIR frequency (my speakers are 5 feet from the front wall).  I think with the panels removed (not measured) that I was indeed experiencing some phase cancellation.

Lastly, using GIK Alpha diffusor/absorber panels (which is what I own), https://www.youtube.com/watch?v=seZyhcf1U3g.  This short video argues that diffusors work mostly on mid-range (I did not know this).  Also diffusors should be directly behind speakers (I always thought this was true).

I put my panels back along the front wall.  A GIK bass trap (2 foot by 2 foot with a range limiter) on the floor behind each speaker's subwoofer.  Next, I reoriented my 6A Alpha panels horizontally (I previously had them vertical to cover the AMT driver).  These are placed on the front wall directly behind the mid-range driver.  Results?  Whoa, huge improvement in sound.  Bass is much tighter.  The mid-range (where most of the action happens) was also greatly improved.  Instruments and vocals were less harsh and clearer.  Even my wife noticed the improvement.  I have diffusor/absorber panels on my rear wall as well.

This was an interesting (and useful) exercise for me.  The X3s are a very forgiving speaker but room treatments are important for best results.

Side note:  I am using my older SVS Ultra Bookshelf speakers (with the GR Research crossover) as my rear surround speakers.  They are 87dB sensitivity while my X3s are 97dB sensitivity.  Gain matching all five speakers has been very difficult.  I accidently stumbled on a thread in the Digital Amplifier circle that discussed this issue.  The author said that moving the lower sensitivity speakers closer to the MLP would greatly improve gain matching.  Guess what?  After moving them half the distance closer, I was much better able to gain match them and now I can hear the ambience sound coming from them.

Marcus

Would love to see some photos of the layout of your acoustic panels. I'm getting ready to reposition my room treatments to accommodate OB speakers, having just switched from a sealed box speaker.

[Desertpilot]

Sure thing.  Here is the view from the MLP.  Listening area is 30 feet long X 14 feet wide.  Panels are not hung on the wall yet.  I just positioned them yesterday to do some listening tests.

Edit:  For some reason the photo posts blurry.  I tried several times.  Instead I'll post a link to GIK.
1.  Monster Bass Trap with Range Limiter (24X24).  https://www.gikacoustics.com/product/gik-acoustics-monster-bass-trap-flexrange-technology/
2.  6A Alpha Panel (2D(a) model) (23X45.5).  https://www.gikacoustics.com/product/6a-alpha-panel-diffusor-absorber/

Marcus

[radarnyc]

Marcus - time to measure! Agreed on the room treatment. Have you tried to remove the carpet? Carpet feels like a good idea but many believe that it can kill (maybe reduce?) the mids and highs.

[Desertpilot]

Marcus - time to measure! Agreed on the room treatment. Have you tried to remove the carpet? Carpet feels like a good idea but many believe that it can kill (maybe reduce?) the mids and highs.

You are absolutely correct.  Time to measure.  I will use Audiolense XO (seems easier than REW and I tested it, it works).  I will post measurements.  Get rid of the carpet?  Not likely, the WAF will never allow it (LOL).

[jtwrace]

You are absolutely correct.  Time to measure.  I will use Audiolense XO (seems easier than REW and I tested it, it works).  I will post measurements.  Get rid of the carpet?  Not likely, the WAF will never allow it (LOL).

The main intended use of AL XO isn't for room measurements.

[Desertpilot]

The main intended use of AL XO isn't for room measurements.

Edit:  I have a very busy day today but I am finally satisfied with speaker positioning and ready for measurements.  I will try REW in addition to Audiolense XO.

[Desertpilot]

Trying to add better quality photos.  Speakers are finally on carpet spikes with GAIA II feet.  Acoustic panels are hung.  I placed a couple bas traps (I only own 2 of them).

[Early B.]

This is an awesome setup!!  What are the dimensions of your room?

While playing in stereo mode, try removing (or laying down) the center speaker. I'm guessing you'll hear a subtle improvement. 

[Desertpilot]

Thank you.  The listening area is part of a great room.  Actual width is 40 feet but the listening area width is only 14 feet.  Length is 30 feet.  I have never felt a need to remove or lower the center speaker when playing stereo music.  The phantom center is perfect.  Room height is a vaulted ceiling from 11 feet to 14 feet in the center.

[doggie]

This is an awesome setup!!  What are the dimensions of your room?

While playing in stereo mode, try removing (or laying down) the center speaker. I'm guessing you'll hear a subtle improvement.

For a long time my understanding has been that having extra speakers in a room is an issue. They act as the opposite of a passive radiator and will absorb some of the energy from the speakers that are active and reduce their dynamics.

As an experiment during two channel playback perhaps just cover the center speaker with some thick blankets to see what the effect is?

[Early B.]

For a long time my understanding has been that having extra speakers in a room is an issue. They act as the opposite of a passive radiator and will absorb some of the energy from the speakers that are active and reduce their dynamics.

Yeah, and it's also a physical barrier that probably impacts your imaging. It's the same rationale for not placing a tall audio rack in between the speakers.

I had a dual servo sub sitting in the middle of my speakers and Danny at GR Research instructed me to lay it on the floor. I was initially reluctant, but once I did, I noticed a subtle improvement in sound. 

[Tyson]

Yeah, and it's also a physical barrier that probably impacts your imaging. It's the same rationale for not placing a tall audio rack in between the speakers.

I had a dual servo sub sitting in the middle of my speakers and Danny at GR Research instructed me to lay it on the floor. I was initially reluctant, but once I did, I noticed a subtle improvement in sound. 

It's my understanding that this is a small effect, and also is worse if the speaker is not plugged in to an amp.  If it's plugged into an amp (that's turned on), the amp stiffens the drivers and causes less absorption from the main speakers. 

[Desertpilot]

Thanks everyone for your thoughts.  Again, I do not hear any issues with having a center channel speaker while listening to stereo recordings.  You will note that the center channel is further back from the MLP that the L/R speakers (to maintain an equidistant point from the MLP).  Ordinarily, I am opposed to furniture between L/R speakers.  But, I listen to almost all 5.0 channel classical music.  The center channel is almost always in use.  Additionally, there is 36 inches of space between each speaker.  This allows for the side cancellation effect (18 inches from the side of each speaker).

In my defense, I modeled my system after a few folks I trust.  Brendon Heinst, recording/mastering engineer at TRPTK reviews his 5 KEF Blade Two speakers in his studio (https://www.youtube.com/watch?v=b7py4zcBqkQ).  Also, Kal Rubinson of Stereophile Magazine uses 3 Revel Ultima2 Studio speakers up front and 2 Revel Performa3 f206 for surrounds.  Jared Sacks of Channel Classics uses 5 B&W 803D Diamond Series loudspeakers for multi-channel in his mixing studio.

Marcus

[Tyson]

Thanks everyone for your thoughts.  Again, I do not hear any issues with having a center channel speaker while listening to stereo recordings.  You will note that the center channel is further back from the MLP that the L/R speakers (to maintain an equidistant point from the MLP).  Ordinarily, I am opposed to furniture between L/R speakers.  But, I listen to almost all 5.0 channel classical music.  The center channel is almost always in use.  Additionally, there is 36 inches of space between each speaker.  This allows for the side cancellation effect (18 inches from the side of each speaker).

In my defense, I modeled my system after a few folks I trust.  Brendon Heinst, recording/mastering engineer at TRPTK reviews his 5 KEF Blade Two speakers in his studio (https://www.youtube.com/watch?v=b7py4zcBqkQ).  Also, Kal Rubinson of Stereophile Magazine uses 3 Revel Ultima2 Studio speakers up front and 2 Revel Performa3 f206 for surrounds.  Jared Sacks of Channel Classics uses 5 B&W 803D Diamond Series loudspeakers for multi-channel in his mixing studio.

Marcus

In case it didn't come through clearly in my previous posts, I think you're fine.

[Desertpilot]

In case it didn't come through clearly in my previous posts, I think you're fine.

Thank you Tyson.

[Desertpilot]

Day 2 of speakers placed straight ahead (no toe-in).  Lots of great listening today.  In every case, soundstage and depth are better than ever.  I don't understand why.  I just know that instrument placement and clarity is more precise but with a robust and fuller sound.  Even my center channel speaker has more depth.

I started this morning with some great piano music, Hannes Minnaar playing Fauré: Piano Music (DSD 64, 5.1), 2016, CC72731.  The piano sounded even closer to having an actual concert grand in my home.  Track No. 2 is especially lovely, "Barcarolle nr.3 opus 42".  Halfway through the track the music blossoms with a magnetic yet delicate energy.  The X3s give the listener accuracy in each note.  The attack and decay is phenomenal.  Available at Native DSD.

Later on, I played a highly recommended classical/jazz crossover album, "Elegy" by Æon Trio.  Another 2016 recording.  Instruments are MAYA FRIDMAN, CELLO, ATZKO KOHASHI, PIANO, FRANS VAN DER HOEVEN, DOUBLE BASS, TTK 0010 (TRPTK), DXD 32/352.8 (5.0).  The X3s give you this trio in your listening room.  The warmth of the cello accented by crisp piano and depth from the double bass weaves a siren song.  I was having lunch while listening and as I moved my head around, each instrument stood out to me as if it was right in front of me.  Almost spooky realistic.  Available at TRPTK and Native DSD.

The configuration I have now with the X3s has become my preferred positioning.  Classical or Jazz, I am overwhelmed by the sound I am getting from these speakers.  Today was a very enjoyable experience because all I needed to do was turn on the music.  No fiddling or fussing.  Just sit back and enjoy.

Marcus

Edit:  My system is Solid State.  I know that many (if not most) AC folks prefer tube equipment.  But, I am extremely happy with my setup (and can't afford any more upgrades).  The one area I will upgrade in the Spring is my music server.  Currently, I am using a Core i9 (9th gen) laptop.  My exaSound S88 DAC was also purchased in May, 2021 with a Teddy Pardot linear power supply.  I've had my Parasound Halo A52+ amp for a few years now.  Acoustic treatments seem adequate.

[Desertpilot]

Update.

I just ran across a very positive Audioholics review of the IsoAcoustics GAIA speaker feet.  https://www.audioholics.com/gadget-reviews/isoacoustics-gaia-isolators-review  The reviewer, Theo Nicolakis, (I'm familiar with him and he's quite knowledgeable) was very impressed,  He mentioned that Spatial Audio Lab is now an OEM distributor (among a growing list of speaker manufacturers).  I use GAIA II, with carpet spikes, on my X3s.  They are an elegant (albeit expensive) solution that works.

Several days now with all three speakers facing forward (no toe-in).  It continues to give me an excellent soundstage and depth with every type of music I throw at my speakers.

Since it's Christmas, I pulled out my favorite music:

-- "A Mormon Tabernacle Choir Christmas", Mormon Tabernacle Choir, Orchestra at Temple Square, Craig Jessop (conductor), 2001, Telarc SACD-60552.  Still available, and cheap, at Amazon.  Sure, it's religious but the choir is absolutely beautiful.
--  "Quite Winter Night", Hoff Ensemble.  Yes, it's in a foreign language, but the music (jazz) is wonderful and definitely wintertime melodies.  Blu-Ray audio from 2L.  I pull the tracks off my blu-rays using DVD Audio Extractor.

Marcus