Soundstage Confusion


I'm in the midst of choosing a new amp for my listening room. Currently, I'm using a NAD M22v2. I just auditioned at home the LTA power amps, and really like their ZTOL40 Reference amp. I also have my faithful Pioneer SPEC-4 that I've had for over 35 years. My components:

Herron VTSP 3A(r02) pre amp
Innous Zenith MKII media streamer
Small Green Computer i7 Roon for DSP device
Audio Mirror Tubadour III SE DAC
Technics SL-1200G TT
Parasound JC3jr phone pre
Tannoy DC8Ti speakers

My room is 13.5x11.5x8.  I've positioned the speakers 34" from the back wall and 22" from the side walls. I've been futzing with speaker placement and my listening position for a while. I have no room treatment yet.

With the NAD and my current setup, I get a huge soundstage and room filling sound. The speakers disappear, but imaging is awful where voices and instruments are well forward of and outside the speakers, with little depth. With the ZTOL40, and no other changes, the main voices are centered between the speakers; instrument separation is clear and overall imaging is great; the soundstage is between the speakers; and the speakers do NOT disappear.  

To test soundstage and imaging, I'm using Chesky Records Jazz Sampler & Audiophile Test files that I downloaded from HDTracks.com, in particular track 10 Introduction and Left-Right Imaging Test, track 11 Listening Environment Diagnostic Recording, and track 12 Acoustic Soundstage (depth) Test. The ZTOL40 passes all tests with flying colors. The NAD fails them all.  I moved the NAD to my rec room system in place of the Pioneer amp. Soundstage is between the speaker; imaging is OK, and voices are centered.  Later today, I'm going to hookup the Pioneer amp to my main system and run the Chesky tests.  That should be interesting.

Before all of this craziness started, I had a different rack.  This past week, I replaced it with a Butcher Block 4 shelf rack. Before that rack, my speaker and sitting positions were slightly different; the NAD soundstage was between the speakers; and imaging was fine.  With all other things being equal, I'm finding it hard to believe that a different rack and/or an amplifier change could cause such a drastic change in soundstage and imaging.  Any ideas anyone?

 
oldschool1948
I'm guessing you have already checked this, but I'll offer this anyway. It sounds like you may have connected one of the speakers out-of-phase when you put your electronics onto the new rack. Have you verified that both speakers are connected properly in-phase, i.e. (+ to +) and (- to -)? If one of the two speakers is out of phase, the soundstage and imaging will be off. 
Yep, that was the first thing I checked.  This has really baffling.
You’re testing too many things at the same time. I suspect the ZOTL amp is not yet burned in and that the soundstage will bloom in time. Take the rack out of the equation - put them both on the floor and re-test using same cables etc.
EDIT: So apparently, LTA say they burn in the amps for 168 hours. Re-test using normal music instead of test tracks. Yes, racks and mounting surfaces can have a huge impact.
Out of phase? Ouch. Connected out of phase the sound would be utterly diffuse to the point of seeming to come from everywhere and nowhere and there would be no image, no soundstage, center or otherwise. OP clearly described imaging both times. Fifty demerits anyone even thought that was a possibility.

I'm finding it hard to believe that a different rack and/or an amplifier change could cause such a drastic change in soundstage and imaging. Any ideas anyone? 

There's a famous quote but I can't remember who said it and won't get it verbatim anyway but you all know it and maybe even are going oh yeah that one- its something along the lines of yeah I changed my mind (or position, or whatever) when the facts change I change my mind, what do you do?

You did a pretty good job making it perfectly clear that the rack and the amp are responsible for the difference. All you have to do now is let your mind agree with reality. Which I highly recommend. Banging your head against a wall is no fun, hurts, and doesn't do the wall any good either.

A nice relaxing method is to pull up my system, gaze upon its sublimely rational form meets function layout, and read the description. I got rid of the rack for exactly the reason you just noticed. But for whatever reason are reluctant to acknowledge. https://systems.audiogon.com/systems/8367
Or if you don't like my advice then listen to noromance who said pretty much the same thing. Only plus the too many things at once thing, which is another good one. But seriously, check it out, ditch the rack, the best rack is no rack, aka the floor.
"Yep, that was the first thing I checked.  This has really baffling."

I  meant to say, "Yep, it was the first thing I checked and my speakers were OK.  This is really baffling."  Sorry about that.  

My NAD and the ZTOL40 are sitting on the floor in between and parallel to the speakers, and not on the rack.  The ZTOL40 is an LTA demo amp and it is well broken in.  For A/B comparisons, I swapped cables and interconnects.  I'm using Blue Jean speaker cables with locking banana plugs and Transparent Super RCA interconnects.

I spent most of my time listening to my regular playlists.  Everything works fine with the ZTOL, not so much anymore with the NAD.  This evening, I'll start experimenting again with speaker positions.

I plan to keep the rack, but move it to the back of my left side wall.  But, first I have to do a little remodeling.  Funny thing, I had several contractors scheduled to give me estimates when this crazy virus mess started.  I've since put that project on hold.   

Hi Millercarbon,

The quotation is attributable to the British economist, John Maynard Keynes:  "When the facts change, I change my mind. What do you do, sir?”  Not to get philosophical on an audio site, but I think the quotation is the epitome of Enlightenment thinking.

Jim Crane


Guys, I appreciate the help.  I'm a techie by trade and I recognize that when troubleshooting, you only change one thing at a time. 

Silly me, I didn't expect that adding a rack would cause this kind of issue when two amps play fine in the same position where the NAD has this massive, unfocused soundstage.  

This is bugging me so I'm going to tinker with speaker position this evening.  I'll probably by the ZTOL40 and the massive, unfocused soundstage problem will go away on its own.  But the techie in me won't rest until I fix or vastly improve on the NAD soundstage problem. 
My 2 cents, which i am sure no-one will read...Assuming your speakers are up to the task and operating correctly;

1. DAC plays a key role in imaging. Some project a wider and deeper soundstage, while others focus the center image more. I’ve found a USB bridge to make a huge difference over straight usb. Straight usb sounds flatter and more muddled. I have dacs that do a better job running into the s/pdif coax input. 
2. In above usb bridge approach, Usb and coax cables can have a major influence on un-muddling and organizing / de-homogenizing the sound.

3. Interconnects and speaker cables will influence the way the soundstage is presented. Some do wider and or deeper. Others do heighth better and focus on center image solidity, sometimes at the cost of sacrificing image organization and resolution overall.

The higher resolution my system becomes the more i hear how these elements all play a significant role in the soundstage focus, clarity, size and organization.



Just some thoughts:

- Small changes in volume can completely change our perception

- Contact corrosion is generally rare, but can happen
- Things get broken (especially when moved around)
- Sometime the thing that changes is us. We need time to adapt to the new norm.
- When you only have 2 speakers, height in the sound-stage is an illusion
Sounds a bit like absolute phase.  Have you tried the invert button? 
After overlooking the real problem for several days, I walked away from it.  Today, I figured out my problem.  I'm embarrassed to say, it was me.  While moving my NAD out of the old rack and placing it on the floor, I somehow moved the Bridge switch from Stereo to Bridge mode. 

What can I say?  Thanks to everyone for trying to help me and please forgive the false alarm.  One thing for sure, I'll make other mistakes in my life, but it won't be that one again.
Awesome. At least you didn't send a cartridge to another continent for a repair when nothing was wrong with it like yours truly. 
oldschool1948,

Thank you for your admitting your mistake. That is the first time I have smiled reading this site in a week. Don't worry, I was laughing with you!
Glad you figured it out. Enjoy your amps.......
@heaudio123.  When I realized what I had done, all I could do was laugh and shake my head.  And although I felt a bit foolish doing it, admitting my mistake was easy.  At my age, I've made so many of them, what's one more :-)!

@reubent It's good to be back in the saddle with my music, and a (properly) working M22v2.
Old school1948, I have made several of these sort of mistakes when changing components. Last one was when I forgot to replace the pre/amp jumpers in an integrated, then changing out several components to solve the lack of sonics. Sometimes panic sets in. One has to laugh at oneself on occasion. 
Mike1949
Sometimes panic sets in. One has to laugh at oneself on occasion.
Ditto!

  Thank you to all, as I have learned much . Its always nice to have a second pair of eyes view a problem . But in our hobby , that usually isn't the case due to distance . Here is a conversation with merit , honesty and politeness . And for me , the importance of a clutter free front wall . You are all a much appreciated breath of fresh air . Cheers , and Good Health , Mike B.   
I’m certain your Herron preamp is great but my ZOTL40 really came to life when I added the ZOTL Preamp. The sound stage grew and it just seemed to bring the ZOTL40 to another level. You might say they were made for each other.

Lance
Lance,

I auditioned the microZOTL preamp with the ZOTL40 power amp and it sounded good.  I listened to it at LTA's office and at home. It is a fine piece of equipment.  My only knock is their Apple remote control lacks too much functionality.  IMHO, LTA needs to provide a much more feature rich remote.

I purchased my Herron used for $2.5K, to my ears, the SQ and sound stage were about the same, but it wasn't $2K better.  I was, however, quite interested in the microZOTL balanced inputs and headphone amp.

I haven't used headphones in years, not since back in the 80's when I was spinning two Technics SL-1200 TT recording to my Teac X-10R R2R and/or partying like it was "1999."  Ah, those were the days :-).  I will eventually buy headphones again, and I don't want to add another component. 

And, I'd like to use the balanced outputs from my phono pre amp.  At that point, I will revisit the microZOTL preamp.  Hopefully, by then, they will have improved the remote.  It may seem like a small thing, but their current one is a show stopper for me.

Johnnie 


You need to use the same test recording for all cases you compare for any meaningful results.  
Imaging and soundstage varies widely with each recording.  There is no rule that vocals are always dead center for example. 
Adding a good quality monophonic recording To the test might be beneficial to determine if you get the focused centered soundstage that should result. 
@mapman I did use the same recordings.  Some vocals and some jazz, and some audiophile test tracks.  I didn’t think of a monophonic recording.  Good advice.  I’ll remember that next time.