Benchmark LA4 Preamp?

     Thanks for the input, yysantabarbara.
     I formerly used a VTL 2.5L tube preamp, with a set of 4 NOS Mullard tubes swapped in, with my very low noise and neutral class D monoblocks. This really allowed the sound characteristics of the VTL and NOS tubes to predominate the overall system sound that I really enjoyed for several years.
     But my system was a combo of music and HT; the VTL had HT/Passthru, I had a separate Parasound AV2500 preamp-processor for 5.1 surround duties and I wanted to streamline my whole system. So, I removed the VTL and the preamp-processor and used my versatile Oppo 105 as a preamp for music, a preamp-processor for 5.1 decoding with surround outputs connected directly to multiple amps as well as a dac and a music server with attached 2TB NAS.
      This system configuration, with audio discs and hi-res FLAC files played back through the Oppo 105, sounds much more neutral but I surprisingly discovered I enjoyed music played through a more accurate and neutral system at least equally as much as through my formerly tube flavored system.
     As a result, I’ve decided to make some major system changes for both music and HT. For music, I purchased a Lumin D2 DAC/Streamer and 18 TB Synology NAS, bought an Oppo 205 to be delivered next Friday and likely a Benchmark LA4 preamp.  I’m even considering buying a used pair of class D Merrill Audio Veritas monoblocks.
     My thinking is this combination of components will create a high quality music system that’s main characteristics will be accuracy, very low noise, very low distortion along with high dynamics. I’m expecting this type of system will provide a soundstage illusion that’s dense, solid and stable that’s perceived as 3 dimensional and natural. However, my main concern is that it may sound sterile if I don’t fully commit to achieving it by investing sufficiently in the research, planning and gear.
     For HT, I’m going to upgrade to a 4K 75" OLED hdtv that, along with the Oppo 205, makes me much more confident in creating a high quality HT system.

Thanks,
Tim

@noble100 Funny that I am thinking of going the opposite direction as you. Being on the "other side" for a while with the Benchmark gear I would recommend you try the AHB2 amp and the LA4 preamp on the 30 day FREE trial. That is a neutral combo and it was very good with my slightly warm KEF LS50. 

You may also want to try A'gon professional reviewer, @Dougles_Shroeoder,  method of connecting the AHB2. I wish I had tried this when I owned the AHB2, just for curiosity sake.

https://forum.audiogon.com/discussions/doug-schroeder-method-double-ic/post?highlight=double%2BAHB2&...

BTW - I have heard the Merrill amps that were $15K before the latest line came out. I think the AHB2 is still something to listen 1st, especially since it is a free home trial.

I'm hoping that there are more LA4 owners that will chime in with their impressions of how this unit sounds in their systems...and how it sounds in comparison to other preamps they have used.

As to the "Shroeder Method" cables...I'm guessing that some will try making their own....and the links to the already made cable that you can purchase are pretty darn expensive at what looks to be over $1k for a pair...   https://www.audiogon.com/listings/lis925e2-teo-audio-double-double-jr-0-6m-new-model-interconnects

In researching the LA4, I’ve read many reviews pairing it or the HPA4 (which really is just an LA4 line stage preamp with a headphone amp) with the very low noise, distortion and neutral Benchmark ABH2 stereo amp that describes very good neutral overall system results.
I think yy’s suggestion that I try out the LA4 or HPA4 with the ABH2 amp together for a 30 day free in-home trial, before purchasing a used pair of Merrill Veritas class D monos for about $5K, is a good one.
Buying and using the HPA4, rather than the LA4, probably also makes more sense since it would likely be more valuable and sellable, having both preamp and headphone amp capabilities, on the used market just in case an ultra low noise, ultra low distortion and neutral system doesn’t match my admittedly high expectations.
However, I really like the small size, weight, cool running and high electrical efficiency qualities of the class D Merrill Veritas monoblocks. I currently use a pair of class D D-Sonic monoblocks that sound very good but I’ve always been very curious, based on the numerous excellent reviews I’ve read on the Veritas, just how good they’d perform in my system. I also like the fact that I can leave the class D amps on 24/7, always optimally warmed up and ready for music or HT. I don’t think leaving the much less efficient class AB ABH2 amp would be a good idea.
The HPA4 seems like an ideal solution for my system. It’s a high quality, low noise, low distortion and sonically neutral component that will allow me to conveniently select either music or HT playback, like a very high quality HT/Passthru switch. I like the fact that I can connect both the Lumin D2’s and the Oppo 205’s left and right channels into the preamp via their balanced XLR connections and match the input and output gain levels on all of them.
I also believe the much more sophisticated and precise volume control on the Benchmark preamp will easily better the what I consider the rather poor volume control performance of my current Parasound Halo P-6 preamp which I reluctantly needed to add once I added the Lumin D2 to my system.

Thanks,
Tim

Update:

     I’ve realized that I’m currently going through one of those stages, that I believe most of us go through periodically, during which even though our systems are performing very well we, nevertheless, get the urge to shake things up a bit and try something different in our systems just for the fun and excitement of it.

     I thought I had a good upgrade experiment all planned out that I’d enjoy by trying to optimize the low noise, low distortion and neutrality of my system and have some fun listening to determine if this resulted in an even more solid, stable, palpable and 3 dimensional soundstage illusion. The main X factor in this experiment being the insertion of the ultra low noise, distortion and neutral qualities of a Benchmark LA4 or HPA4 preamp in my system to replace my current Parasound Halo P6 preamp.

     After a few days of pondering my planned experiment and my desired results, an even more solid, stable, palpable and 3 dimensional soundstage illusion, I’m currently 2nd guessing my planned experiment and wondering if inserting a used Mark Levinson 326S preamp (for about double the price of the LA4 or HPA4 options) has a better chance of providing my overall system goals primarily for music playback. 

Here’s an older Stereophile review of the 326S: 
https://www.stereophile.com/solidpreamps/106ml/index.html

Here’s an example of one in very good condition currently for sale:
https://www.usaudiomart.com/details/649569175-mark-levinson-no326s/

Any thoughts?

Thanks,
Tim