Could use some help with a tough match

Thank you for all of your great feedback. What started this thread is I was looking at a BAT VAT 51se so called BAT and Threshold directly to discuss compatability. What prompted the call was the Stereophile review of the BAT which cautioned against matching low inpedence input on some amps with the BAT's 410 ohm balanced output. BAT said that it should be ok but running a balanced unit into unbalanced amps would certainly would not allow me to get the maximum performance the preamp is capable of. Threshold told me I would not have close to the 10x ratio that is the general rule of thumb for a good match. Also that a lot of tube gear had high output impedence. I must admit that the feedback I am receiving from each of you is different so I am a little confused. I really appeciate the input because I need to narrow the field a bit before I can shop for the appropriate preamp. My SA 1's have always served me well ( Maggie's, Thiel's) which is why I really wanted to match them up. I currently have 2 Threshold pre's but time to upgrade to current technology (a remote control :}

John,
If I understand the conversation correctly with Threshold if I installed balanced inputs it is not a matter of straight math. The input impedence of the Threshold's would be approximately 600 ohms balanced. That was the issue. Certainly not an engineer but that's the feedback I received.

John,
Really sorry if I came across poorly. I certainly did not mean to come across negatively and truly appreciate and welcome your suggestions and feedback. This is my first time posting here because I am trying to learn ( at least a little... In all these years I have never owned a tube preamp, or a remote control :) on my systems so I am really venturing into new territory . My general principle has been simplicity of design (less parts, loops and interfaces) = less noise and better sound. I think the challenge for me is the number of quality components that are going to all balanced inputs and outputs with some making a concession to RCA outputs and inputs for convenience. ie in Stereophile measurements of the ARC reference 3 it was pretty obvious that measurements were better in balanced mode. I know measurements don't always tell the story but it's a start.
So thanks again for your feedback it really is greatly appreciated !

All my best,
Don

Thanks John,
The driver behind my change is I am in the process of upgrading. From what I have learned the general concensus is that a tube preamp is a better match for my Sonus Faber Amati's. So if I am going to change I might as well explore the world of tubes.
Cheers,
Don

Thank you Unsound. Excellent post, you have helped me crystalize my way forward. I will leave the Thresholds unbalanced because frankly I firmly believe they match up well with my speakers so will look for a single ended ARC, Sonic Frontiers or c-j preamp but welcome other suggestions. I looked at the ARC 3 but once again would be paying for technology ( balanced operations) I won't use. Any recommendations on a good ARC, Sonic Frontiers, or c-j models? I don't mind if its a few years old but I really want a quality unit. It will be the heart of my system so a class A component is essential ( quiet, big soundstage and dynamics ). I will start researching again but if anyone has a slam dunk recommendation I would appreciate your input.
Thanks,
Don